Update deps

* fix(pipe-parser): add support for more sophisticated expressions

.github/FUNDING.yml

@@ -1,2 +1,2 @@
-github: #biesbjerg
+github: biesbjerg
 custom: https://donate.biesbjerg.com

.gitignore

@@ -8,6 +8,8 @@ npm-debug.log*
 
 # Compiled files
 dist
+src/**/*.js
+tests/**/*.js
 
 # Extracted strings
 strings.json

.npmrc

@@ -0,0 +1 @@
+engine-strict=true

README.md

@@ -2,13 +2,11 @@ If this tool saves you time, please consider making a donation towards the conti
 
 [![Donate](images/donate-badge.png)](https://donate.biesbjerg.com)
 
-# Usage
-
-## ngx-translate-extract
+# ngx-translate-extract
 Extract translatable (ngx-translate) strings and save as a JSON or Gettext pot file.
 Merges with existing strings if the output file already exists.
 
-### Usage
+## Install
 Install the package in your project:
 
 `npm install @biesbjerg/ngx-translate-extract --save-dev`
@@ -17,33 +15,28 @@ Add a script to your project's `package.json`:
 ```json
 ...
 "scripts": {
-  "extract-i18n": "ngx-translate-extract --input ./src --output ./src/assets/i18n/ --clean --sort --format namespaced-json"
+  "i18n:init": "ngx-translate-extract --input ./src --output ./src/assets/i18n/template.json --key-as-default-value --replace --format json",
+  "i18n:extract": "ngx-translate-extract --input ./src --output ./src/assets/i18n/{en,da,de,fi,nb,nl,sv}.json --clean --format json"
 }
 ...
 ```
 You can now run `npm run extract-i18n` and it will extract strings from your project.
 
-### Examples
+## Usage
 
 **Extract from dir and save to file**
 
-`ngx-translate-extract --input ./src --output ./src/assets/i18n/template.json`
+`ngx-translate-extract --input ./src --output ./src/assets/i18n/strings.json`
 
 **Extract from multiple dirs**
 
-`ngx-translate-extract --input ./src-a ./src-b --output ./src/assets/i18n/template.json`
+`ngx-translate-extract --input ./src-a ./src-b --output ./src/assets/i18n/strings.json`
 
 
 **Extract and save to multiple files using path expansion**
 
-_Note: This method does not work on Windows!_
-
 `ngx-translate-extract --input ./src --output ./src/i18n/{da,en}.json`
 
-On Windows you must specify each output destination individually:
-
-`ngx-translate-extract --input ./src --output ./src/i18n/da.json ./src/i18n/en.json`
-
 ### JSON indentation
 Tabs are used by default for indentation when saving extracted strings in json formats:
 
@@ -51,8 +44,8 @@ If you want to use spaces instead, you can do the following:
 
 `ngx-translate-extract --input ./src --output ./src/i18n/en.json --format-indentation '  '`
 
-## Mark strings for extraction using a marker function
-If, for some reason, you want to extract strings not passed directly to `TranslateService`'s `get()` or `instant()` methods, you can wrap them in a custom marker function to let `ngx-translate-extract` know you want to extract them.
+### Marker function
+If you want to extract strings that are not passed directly to `TranslateService`'s `get()`/`instant()`/`stream()` methods, you can wrap them in a marker function to let `ngx-translate-extract` know you want to extract them.
 
 Install marker function:
 `npm install @biesbjerg/ngx-translate-extract-marker`
@@ -63,10 +56,6 @@ import { marker } from '@biesbjerg/ngx-translate-extract-marker';
 marker('Extract me');
 ```
 
-Add the `marker` argument when running the extract script:
-
-`ngx-translate-extract ... -m extract`
-
 You can alias the marker function if needed:
 
 ```ts
@@ -75,35 +64,45 @@ import { marker as _ } from '@biesbjerg/ngx-translate-extract-marker';
 _('Extract me');
 ```
 
-`ngx-translate-extract ... -m _`
+_Note: `ngx-translate-extract` will automatically detect the import name_
 
-## Commandline arguments
-```shell
+### Commandline arguments
+```
 Usage:
 ngx-translate-extract [options]
 
+Output
+  --format, -f                Format    [string] [choices: "json", "namespaced-json", "pot"] [default: "json"]
+  --format-indentation, --fi  Format indentation (JSON/Namedspaced JSON)                [string] [default: "	"]
+  --sort, -s                  Sort strings in alphabetical order                                     [boolean]
+  --clean, -c                 Remove obsolete strings after merge                                    [boolean]
+  --replace, -r               Replace the contents of output file if it exists (Merges by default)   [boolean]
+
+Extracted key value (defaults to empty string)
+  --key-as-default-value, -k     Use key as default value                                            [boolean]
+  --null-as-default-value, -n    Use null as default value                                           [boolean]
+  --string-as-default-value, -d  Use string as default value                                          [string]
+
 Options:
   --version, -v  Show version number                                                                 [boolean]
   --help, -h     Show help                                                                           [boolean]
-  --input, -i                 Paths you would like to extract strings from. You
-                              can use path expansion, glob patterns and multiple
-                              paths
-                      [array] [default: current working path]
-  --patterns, -p              Extract strings from the following file patterns
-                                    [array] [default: ["/**/*.html","/**/*.ts"]]
-  --output, -o                Paths where you would like to save extracted
-                              strings. You can use path expansion, glob patterns
-                              and multiple paths              [array] [required]
-  --marker, -m                Extract strings passed to a marker function
-                                                       [string] [default: false]
-  --format, -f                Output format
-          [string] [choices: "json", "namespaced-json", "pot"] [default: "json"]
-  --format-indentation, --fi  Output format indentation   [string] [default: "	"]
-  --replace, -r               Replace the contents of output file if it exists
-                              (Merges by default)     [boolean] [default: false]
-  --sort, -s                  Sort strings in alphabetical order when saving
-                                                      [boolean] [default: false]
-  --clean, -c                 Remove obsolete strings when merging
-                                                      [boolean] [default: false]
-  --key-as-default-value, -k  Use key as default value for translations
-                                                      [boolean] [default: false]
+  --input, -i    Paths you would like to extract strings from. You can use path expansion, glob patterns and
+                 multiple paths        [array] [required] [default: ["/Users/kim/apps/ngx-translate-extract"]]
+  --output, -o   Paths where you would like to save extracted strings. You can use path expansion, glob
+                 patterns and multiple paths                                                [array] [required]
+
+Examples:
+  ngx-translate-extract -i ./src-a/ -i ./src-b/ -o strings.json           Extract (ts, html) from multiple paths
+  ngx-translate-extract -i './{src-a,src-b}/' -o strings.json             Extract (ts, html) from multiple paths using brace
+                                                           expansion
+  ngx-translate-extract -i ./src/ -o ./i18n/da.json -o ./i18n/en.json     Extract (ts, html) and save to da.json and en.json
+  ngx-translate-extract -i ./src/ -o './i18n/{en,da}.json'                Extract (ts, html) and save to da.json and en.json
+                                                           using brace expansion
+  ngx-translate-extract -i './src/**/*.{ts,tsx,html}' -o strings.json     Extract from ts, tsx and html
+  ngx-translate-extract -i './src/**/!(*.spec).{ts,html}' -o              Extract from ts, html, excluding files with ".spec"
+  strings.json
+```
+
+## Note for GetText users
+
+Please pay attention of which version of `gettext-parser` you actually use in your project. For instance, `gettext-parser:1.2.2` does not support HTML tags in translation keys.

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@biesbjerg/ngx-translate-extract",
-  "version": "3.0.4",
+  "version": "7.0.3",
   "description": "Extract strings from projects using ngx-translate",
   "main": "dist/index.js",
   "typings": "dist/index.d.ts",
@@ -14,10 +14,27 @@
   "scripts": {
     "build": "npm run clean && tsc",
     "watch": "npm run clean && tsc --watch",
-    "clean": "rm -rf ./dist",
+    "clean": "rimraf ./dist",
     "lint": "tslint --force './src/**/*.ts'",
     "test": "mocha -r ts-node/register tests/**/*.spec.ts"
   },
+  "husky": {
+    "hooks": {
+      "pre-commit": "lint-staged && npm test"
+    }
+  },
+  "prettier": {
+    "trailingComma": "none",
+    "printWidth": 145,
+    "useTabs": true,
+    "singleQuote": true
+  },
+  "lint-staged": {
+    "{src,tests}/**/*.{ts}": [
+      "tslint --project tsconfig.json -c tslint.commit.json --fix",
+      "prettier --write"
+    ]
+  },
   "repository": {
     "type": "git",
     "url": "https://github.com/biesbjerg/ngx-translate-extract.git"
@@ -40,33 +57,48 @@
   },
   "homepage": "https://github.com/biesbjerg/ngx-translate-extract",
   "engines": {
-    "node": ">=4.3.2"
+    "node": ">=11.15.0"
   },
   "config": {},
   "devDependencies": {
-    "@types/chai": "^4.2.0",
-    "@types/flat": "^0.0.28",
-    "@types/glob": "^7.1.1",
-    "@types/mkdirp": "^0.5.2",
-    "@types/mocha": "^5.2.7",
-    "@types/yargs": "^13.0.2",
-    "chai": "^4.2.0",
-    "mocha": "^6.2.0",
-    "ts-node": "^8.3.0",
-    "tslint": "^5.19.0",
-    "tslint-eslint-rules": "^5.4.0"
+    "@angular/compiler": "^11.2.9",
+    "@types/braces": "^3.0.0",
+    "@types/chai": "^4.2.16",
+    "@types/flat": "^5.0.1",
+    "@types/gettext-parser": "4.0.0",
+    "@types/glob": "^7.1.3",
+    "@types/mkdirp": "^1.0.1",
+    "@types/mocha": "^8.2.2",
+    "@types/node": "^14.14.37",
+    "@types/yargs": "^16.0.1",
+    "braces": "^3.0.2",
+    "chai": "^4.3.4",
+    "husky": "^6.0.0",
+    "lint-staged": "^10.5.4",
+    "mocha": "^8.3.2",
+    "prettier": "^2.2.1",
+    "rimraf": "^3.0.2",
+    "ts-node": "^9.1.1",
+    "tslint": "^6.1.3",
+    "tslint-config-prettier": "^1.18.0",
+    "tslint-eslint-rules": "^5.4.0",
+    "tslint-etc": "^1.13.9",
+    "typescript": "^4.2.4"
+  },
+  "peerDependencies": {
+    "@angular/compiler": ">=8.0.0",
+    "typescript": ">=3.0.0"
   },
   "dependencies": {
-    "@angular/compiler": "^8.2.2",
-    "boxen": "^4.1.0",
-    "colorette": "^1.1.0",
-    "flat": "github:lenchvolodymyr/flat#ffe77ef",
-    "gettext-parser": "^4.0.1",
-    "glob": "^7.1.4",
-    "mkdirp": "^0.5.1",
+    "@phenomnomnominal/tsquery": "^4.1.1",
+    "boxen": "^5.0.1",
+    "colorette": "^1.2.2",
+    "flat": "^5.0.2",
+    "gettext-parser": "^4.0.4",
+    "glob": "^7.1.6",
+    "mkdirp": "^1.0.4",
     "path": "^0.12.7",
-    "terminal-link": "^1.3.0",
-    "typescript": "^3.5.3",
-    "yargs": "^14.0.0"
+    "terminal-link": "^2.1.1",
+    "yargs": "^16.2.0"
   }
 }

src/cli/cli.ts

@@ -1,21 +1,35 @@
-import * as fs from 'fs';
 import * as yargs from 'yargs';
+import { red, green } from 'colorette';
 
 import { ExtractTask } from './tasks/extract.task';
 import { ParserInterface } from '../parsers/parser.interface';
 import { PipeParser } from '../parsers/pipe.parser';
 import { DirectiveParser } from '../parsers/directive.parser';
 import { ServiceParser } from '../parsers/service.parser';
-import { FunctionParser } from '../parsers/function.parser';
+import { MarkerParser } from '../parsers/marker.parser';
 import { PostProcessorInterface } from '../post-processors/post-processor.interface';
 import { SortByKeyPostProcessor } from '../post-processors/sort-by-key.post-processor';
 import { KeyAsDefaultValuePostProcessor } from '../post-processors/key-as-default-value.post-processor';
+import { NullAsDefaultValuePostProcessor } from '../post-processors/null-as-default-value.post-processor';
+import { StringAsDefaultValuePostProcessor } from '../post-processors/string-as-default-value.post-processor';
 import { PurgeObsoleteKeysPostProcessor } from '../post-processors/purge-obsolete-keys.post-processor';
 import { CompilerInterface } from '../compilers/compiler.interface';
 import { CompilerFactory } from '../compilers/compiler.factory';
+import { normalizePaths } from '../utils/fs-helpers';
 import { donateMessage } from '../utils/donate';
 
-export const cli = yargs
+// First parsing pass to be able to access pattern argument for use input/output arguments
+const y = yargs.option('patterns', {
+	alias: 'p',
+	describe: 'Default patterns',
+	type: 'array',
+	default: ['/**/*.html', '/**/*.ts'],
+	hidden: true
+});
+
+const parsed = y.parse();
+
+export const cli = y
 	.usage('Extract strings from files for translation.\nUsage: $0 [options]')
 	.version(require(__dirname + '/../../package.json').version)
 	.alias('version', 'v')
@@ -24,24 +38,14 @@ export const cli = yargs
 	.option('input', {
 		alias: 'i',
 		describe: 'Paths you would like to extract strings from. You can use path expansion, glob patterns and multiple paths',
-		default: process.env.PWD,
+		default: [process.env.PWD],
 		type: 'array',
-		normalize: true
+		normalize: true,
+		required: true
 	})
-	.check(options => {
-		options.input.forEach((dir: string) => {
-			if (!fs.existsSync(dir) || !fs.statSync(dir).isDirectory()) {
-				throw new Error(`The path you supplied was not found: '${dir}'`);
-			}
-
-		});
-		return true;
-	})
-	.option('patterns', {
-		alias: 'p',
-		describe: 'Extract strings from the following file patterns',
-		type: 'array',
-		default: ['/**/*.html', '/**/*.ts']
+	.coerce('input', (input: string[]) => {
+		const paths = normalizePaths(input, parsed.patterns);
+		return paths;
 	})
 	.option('output', {
 		alias: 'o',
@@ -50,68 +54,75 @@ export const cli = yargs
 		normalize: true,
 		required: true
 	})
-	.option('marker', {
-		alias: 'm',
-		describe: 'Extract strings passed to a marker function',
-		default: false,
-		type: 'string'
+	.coerce('output', (output: string[]) => {
+		const paths = normalizePaths(output, parsed.patterns);
+		return paths;
 	})
 	.option('format', {
 		alias: 'f',
-		describe: 'Output format',
+		describe: 'Format',
 		default: 'json',
 		type: 'string',
 		choices: ['json', 'namespaced-json', 'pot']
 	})
 	.option('format-indentation', {
 		alias: 'fi',
-		describe: 'Output format indentation',
+		describe: 'Format indentation (JSON/Namedspaced JSON)',
 		default: '\t',
 		type: 'string'
 	})
 	.option('replace', {
 		alias: 'r',
 		describe: 'Replace the contents of output file if it exists (Merges by default)',
-		default: false,
 		type: 'boolean'
 	})
 	.option('sort', {
 		alias: 's',
-		describe: 'Sort strings in alphabetical order when saving',
-		default: false,
+		describe: 'Sort strings in alphabetical order',
 		type: 'boolean'
 	})
 	.option('clean', {
 		alias: 'c',
-		describe: 'Remove obsolete strings when merging',
-		default: false,
+		describe: 'Remove obsolete strings after merge',
 		type: 'boolean'
 	})
 	.option('key-as-default-value', {
 		alias: 'k',
-		describe: 'Use key as default value for translations',
-		default: false,
-		type: 'boolean'
+		describe: 'Use key as default value',
+		type: 'boolean',
+		conflicts: ['null-as-default-value', 'string-as-default-value']
 	})
+	.option('null-as-default-value', {
+		alias: 'n',
+		describe: 'Use null as default value',
+		type: 'boolean',
+		conflicts: ['key-as-default-value', 'string-as-default-value']
+	})
+	.option('string-as-default-value', {
+		alias: 'd',
+		describe: 'Use string as default value',
+		type: 'string',
+		conflicts: ['null-as-default-value', 'key-as-default-value']
+	})
+	.group(['format', 'format-indentation', 'sort', 'clean', 'replace'], 'Output')
+	.group(['key-as-default-value', 'null-as-default-value', 'string-as-default-value'], 'Extracted key value (defaults to empty string)')
+	.conflicts('key-as-default-value', 'null-as-default-value')
+	.example(`$0 -i ./src-a/ -i ./src-b/ -o strings.json`, 'Extract (ts, html) from multiple paths')
+	.example(`$0 -i './{src-a,src-b}/' -o strings.json`, 'Extract (ts, html) from multiple paths using brace expansion')
+	.example(`$0 -i ./src/ -o ./i18n/da.json -o ./i18n/en.json`, 'Extract (ts, html) and save to da.json and en.json')
+	.example(`$0 -i ./src/ -o './i18n/{en,da}.json'`, 'Extract (ts, html) and save to da.json and en.json using brace expansion')
+	.example(`$0 -i './src/**/*.{ts,tsx,html}' -o strings.json`, 'Extract from ts, tsx and html')
+	.example(`$0 -i './src/**/!(*.spec).{ts,html}' -o strings.json`, 'Extract from ts, html, excluding files with ".spec" in filename')
+	.wrap(110)
 	.exitProcess(true)
 	.parse(process.argv);
 
 const extractTask = new ExtractTask(cli.input, cli.output, {
-	replace: cli.replace,
-	patterns: cli.patterns
+	replace: cli.replace
 });
 
 // Parsers
-const parsers: ParserInterface[] = [
-	new PipeParser(),
-	new DirectiveParser(),
-	new ServiceParser()
-];
-if (cli.marker) {
-	parsers.push(new FunctionParser({
-		identifier: cli.marker
-	}));
-}
+const parsers: ParserInterface[] = [new PipeParser(), new DirectiveParser(), new ServiceParser(), new MarkerParser()];
 extractTask.setParsers(parsers);
 
 // Post processors
@@ -121,7 +132,12 @@ if (cli.clean) {
 }
 if (cli.keyAsDefaultValue) {
 	postProcessors.push(new KeyAsDefaultValuePostProcessor());
+} else if (cli.nullAsDefaultValue) {
+	postProcessors.push(new NullAsDefaultValuePostProcessor());
+} else if (cli.stringAsDefaultValue) {
+	postProcessors.push(new StringAsDefaultValuePostProcessor({ defaultValue: cli.stringAsDefaultValue as string }));
 }
+
 if (cli.sort) {
 	postProcessors.push(new SortByKeyPostProcessor());
 }
@@ -133,6 +149,13 @@ const compiler: CompilerInterface = CompilerFactory.create(cli.format, {
 });
 extractTask.setCompiler(compiler);
 
+// Run task
+try {
 	extractTask.execute();
-
+	console.log(green('\nDone.\n'));
 	console.log(donateMessage);
+	process.exit(0);
+} catch (e) {
+	console.log(red(`\nAn error occurred: ${e}\n`));
+	process.exit(1);
+}

src/cli/tasks/extract.task.ts

@@ -4,7 +4,7 @@ import { ParserInterface } from '../../parsers/parser.interface';
 import { PostProcessorInterface } from '../../post-processors/post-processor.interface';
 import { CompilerInterface } from '../../compilers/compiler.interface';
 
-import { cyan, green, bold, dim } from 'colorette';
+import { cyan, green, bold, dim, red } from 'colorette';
 import * as glob from 'glob';
 import * as fs from 'fs';
 import * as path from 'path';
@@ -12,14 +12,11 @@ import * as mkdirp from 'mkdirp';
 
 export interface ExtractTaskOptionsInterface {
 	replace?: boolean;
-	patterns?: string[];
 }
 
 export class ExtractTask implements TaskInterface {
-
 	protected options: ExtractTaskOptionsInterface = {
-		replace: false,
-		patterns: []
+		replace: false
 	};
 
 	protected parsers: ParserInterface[] = [];
@@ -27,8 +24,8 @@ export class ExtractTask implements TaskInterface {
 	protected compiler: CompilerInterface;
 
 	public constructor(protected inputs: string[], protected outputs: string[], options?: ExtractTaskOptionsInterface) {
-		this.inputs = inputs.map(input => path.resolve(input));
-		this.outputs = outputs.map(output => path.resolve(output));
+		this.inputs = inputs.map((input) => path.resolve(input));
+		this.outputs = outputs.map((output) => path.resolve(output));
 		this.options = { ...this.options, ...options };
 	}
 
@@ -47,7 +44,7 @@ export class ExtractTask implements TaskInterface {
 
 		this.out(bold('Saving:'));
 
-		this.outputs.forEach(output => {
+		this.outputs.forEach((output) => {
 			let dir: string = output;
 			let filename: string = `strings.${this.compiler.extension}`;
 			if (!fs.existsSync(output) || !fs.statSync(output).isDirectory()) {
@@ -59,26 +56,33 @@ export class ExtractTask implements TaskInterface {
 
 			let existing: TranslationCollection = new TranslationCollection();
 			if (!this.options.replace && fs.existsSync(outputPath)) {
+				try {
 					existing = this.compiler.parse(fs.readFileSync(outputPath, 'utf-8'));
+				} catch (e) {
+					this.out(`%s %s`, dim(`- ${outputPath}`), red(`[ERROR]`));
+					throw e;
+				}
 			}
 
 			// merge extracted strings with existing
 			const draft = extracted.union(existing);
 
-			if (existing.isEmpty()) {
-				this.out(dim(`- ${outputPath}`));
-			} else {
-				this.out(dim(`- ${outputPath} (merged)`));
-			}
-
 			// Run collection through post processors
 			const final = this.process(draft, extracted, existing);
 
-			// Save to file
+			// Save
+			try {
+				let event = 'CREATED';
+				if (fs.existsSync(outputPath)) {
+					this.options.replace ? (event = 'REPLACED') : (event = 'MERGED');
+				}
 				this.save(outputPath, final);
+				this.out(`%s %s`, dim(`- ${outputPath}`), green(`[${event}]`));
+			} catch (e) {
+				this.out(`%s %s`, dim(`- ${outputPath}`), red(`[ERROR]`));
+				throw e;
+			}
 		});
-
-		this.out(green('\nDone.\n'));
 	}
 
 	public setParsers(parsers: ParserInterface[]): this {
@@ -100,24 +104,27 @@ export class ExtractTask implements TaskInterface {
 	 * Extract strings from specified input dirs using configured parsers
 	 */
 	protected extract(): TranslationCollection {
-		let extracted: TranslationCollection = new TranslationCollection();
-		this.inputs.forEach(dir => {
-			this.readDir(dir, this.options.patterns).forEach(path => {
-				this.out(dim('- %s'), path);
-				const contents: string = fs.readFileSync(path, 'utf-8');
-				this.parsers.forEach(parser => {
-					extracted = extracted.union(parser.extract(contents, path));
+		let collection: TranslationCollection = new TranslationCollection();
+		this.inputs.forEach((pattern) => {
+			this.getFiles(pattern).forEach((filePath) => {
+				this.out(dim('- %s'), filePath);
+				const contents: string = fs.readFileSync(filePath, 'utf-8');
+				this.parsers.forEach((parser) => {
+					const extracted = parser.extract(contents, filePath);
+					if (extracted instanceof TranslationCollection) {
+						collection = collection.union(extracted);
+					}
 				});
 			});
 		});
-		return extracted;
+		return collection;
 	}
 
 	/**
 	 * Run strings through configured post processors
 	 */
 	protected process(draft: TranslationCollection, extracted: TranslationCollection, existing: TranslationCollection): TranslationCollection {
-		this.postProcessors.forEach(postProcessor => {
+		this.postProcessors.forEach((postProcessor) => {
 			draft = postProcessor.process(draft, extracted, existing);
 		});
 		return draft;
@@ -136,14 +143,10 @@ export class ExtractTask implements TaskInterface {
 	}
 
 	/**
-	 * Get all files in dir matching patterns
+	 * Get all files matching pattern
 	 */
-	protected readDir(dir: string, patterns: string[]): string[] {
-		return patterns.reduce((results, pattern) => {
-			return glob.sync(dir + pattern)
-				.filter(path => fs.statSync(path).isFile())
-				.concat(results);
-		}, []);
+	protected getFiles(pattern: string): string[] {
+		return glob.sync(pattern).filter((filePath) => fs.statSync(filePath).isFile());
 	}
 
 	protected out(...args: any[]): void {
@@ -153,7 +156,7 @@ export class ExtractTask implements TaskInterface {
 	protected printEnabledParsers(): void {
 		this.out(cyan('Enabled parsers:'));
 		if (this.parsers.length) {
-			this.out(cyan(dim(this.parsers.map(parser => `- ${parser.constructor.name}`).join('\n'))));
+			this.out(cyan(dim(this.parsers.map((parser) => `- ${parser.constructor.name}`).join('\n'))));
 		} else {
 			this.out(cyan(dim('(none)')));
 		}
@@ -163,7 +166,7 @@ export class ExtractTask implements TaskInterface {
 	protected printEnabledPostProcessors(): void {
 		this.out(cyan('Enabled post processors:'));
 		if (this.postProcessors.length) {
-			this.out(cyan(dim(this.postProcessors.map(postProcessor => `- ${postProcessor.constructor.name}`).join('\n'))));
+			this.out(cyan(dim(this.postProcessors.map((postProcessor) => `- ${postProcessor.constructor.name}`).join('\n'))));
 		} else {
 			this.out(cyan(dim('(none)')));
 		}
@@ -175,5 +178,4 @@ export class ExtractTask implements TaskInterface {
 		this.out(cyan(dim(`- ${this.compiler.constructor.name}`)));
 		this.out();
 	}
-
 }

src/compilers/compiler.factory.ts

@@ -4,14 +4,16 @@ import { NamespacedJsonCompiler } from '../compilers/namespaced-json.compiler';
 import { PoCompiler } from '../compilers/po.compiler';
 
 export class CompilerFactory {
-
 	public static create(format: string, options?: {}): CompilerInterface {
 		switch (format) {
-			case 'pot': return new PoCompiler(options);
-			case 'json': return new JsonCompiler(options);
-			case 'namespaced-json': return new NamespacedJsonCompiler(options);
-			default: throw new Error(`Unknown format: ${format}`);
+			case 'pot':
+				return new PoCompiler(options);
+			case 'json':
+				return new JsonCompiler(options);
+			case 'namespaced-json':
+				return new NamespacedJsonCompiler(options);
+			default:
+				throw new Error(`Unknown format: ${format}`);
 		}
 	}
-
 }

src/compilers/compiler.interface.ts

@@ -1,11 +1,9 @@
 import { TranslationCollection } from '../utils/translation.collection';
 
 export interface CompilerInterface {
-
 	extension: string;
 
 	compile(collection: TranslationCollection): string;
 
 	parse(contents: string): TranslationCollection;
-
 }

src/compilers/json.compiler.ts

@@ -5,7 +5,6 @@ import { stripBOM } from '../utils/utils';
 import { flatten } from 'flat';
 
 export class JsonCompiler implements CompilerInterface {
-
 	public indentation: string = '\t';
 
 	public extension: string = 'json';
@@ -29,7 +28,6 @@ export class JsonCompiler implements CompilerInterface {
 	}
 
 	protected isNamespacedJsonFormat(values: any): boolean {
-		return Object.keys(values).some(key => typeof values[key] === 'object');
+		return Object.keys(values).some((key) => typeof values[key] === 'object');
 	}
-
 }

src/compilers/namespaced-json.compiler.ts

@@ -5,7 +5,6 @@ import { stripBOM } from '../utils/utils';
 import { flatten, unflatten } from 'flat';
 
 export class NamespacedJsonCompiler implements CompilerInterface {
-
 	public indentation: string = '\t';
 
 	public extension = 'json';
@@ -27,5 +26,4 @@ export class NamespacedJsonCompiler implements CompilerInterface {
 		const values: {} = flatten(JSON.parse(stripBOM(contents)));
 		return new TranslationCollection(values);
 	}
-
 }

src/compilers/po.compiler.ts

@@ -1,10 +1,9 @@
 import { CompilerInterface } from './compiler.interface';
 import { TranslationCollection, TranslationType } from '../utils/translation.collection';
 
-import * as gettext from 'gettext-parser';
+import { po } from 'gettext-parser';
 
 export class PoCompiler implements CompilerInterface {
-
 	public extension: string = 'po';
 
 	/**
@@ -24,34 +23,38 @@ export class PoCompiler implements CompilerInterface {
 			},
 			translations: {
 				[this.domain]: Object.keys(collection.values).reduce((translations, key) => {
-					translations[key] = {
+					return {
+						...translations,
+						[key]: {
 							msgid: key,
 							msgstr: collection.get(key)
+						}
 					};
-					return translations;
 				}, {} as any)
 			}
 		};
 
-		return gettext.po.compile(data);
+		return po.compile(data).toString('utf8');
 	}
 
 	public parse(contents: string): TranslationCollection {
 		const collection = new TranslationCollection();
 
-		const po = gettext.po.parse(contents, 'utf8');
-		if (!po.translations.hasOwnProperty(this.domain)) {
+		const parsedPo = po.parse(contents, 'utf8');
+
+		if (!parsedPo.translations.hasOwnProperty(this.domain)) {
 			return collection;
 		}
 
-		const values = Object.keys(po.translations[this.domain])
-			.filter(key => key.length > 0)
-			.reduce((values, key) => {
-				values[key] = po.translations[this.domain][key].msgstr.pop();
-				return values;
+		const values = Object.keys(parsedPo.translations[this.domain])
+			.filter((key) => key.length > 0)
+			.reduce((result, key) => {
+				return {
+					...result,
+					[key]: parsedPo.translations[this.domain][key].msgstr.pop()
+				};
 			}, {} as TranslationType);
 
 		return new TranslationCollection(values);
 	}
-
 }

src/declarations.d.ts

@@ -1 +0,0 @@
-declare module 'gettext-parser';

src/index.ts

@@ -6,11 +6,10 @@ export * from './cli/tasks/task.interface';
 export * from './cli/tasks/extract.task';
 
 export * from './parsers/parser.interface';
-export * from './parsers/abstract-ast.parser';
 export * from './parsers/directive.parser';
 export * from './parsers/pipe.parser';
 export * from './parsers/service.parser';
-export * from './parsers/function.parser';
+export * from './parsers/marker.parser';
 
 export * from './compilers/compiler.interface';
 export * from './compilers/compiler.factory';

src/parsers/abstract-ast.parser.ts

@@ -1,48 +0,0 @@
-import {
-	createSourceFile,
-	SourceFile,
-	CallExpression,
-	Node,
-	SyntaxKind,
-	StringLiteral,
-	NoSubstitutionTemplateLiteral
-} from 'typescript';
-
-export abstract class AbstractAstParser {
-
-	protected sourceFile: SourceFile;
-
-	protected createSourceFile(path: string, contents: string): SourceFile {
-		return createSourceFile(path, contents, null, /*setParentNodes */ false);
-	}
-
-	/**
-	 * Get strings from function call's first argument
-	 */
-	protected getStringLiterals(callNode: CallExpression): string[] {
-		if (!callNode.arguments.length) {
-			return[];
-		}
-
-		const firstArg = callNode.arguments[0];
-
-		return this.findNodes(firstArg, [
-			SyntaxKind.StringLiteral,
-			SyntaxKind.NoSubstitutionTemplateLiteral
-		])
-		.map((node: StringLiteral | NoSubstitutionTemplateLiteral) => node.text);
-	}
-
-	/**
-	 * Find all child nodes of a kind
-	 */
-	protected findNodes(node: Node, kinds: SyntaxKind[]): Node[] {
-		const childrenNodes: Node[] = node.getChildren(this.sourceFile);
-		const initialValue: Node[] = kinds.includes(node.kind) ? [node] : [];
-
-		return childrenNodes.reduce((result: Node[], childNode: Node) => {
-			return result.concat(this.findNodes(childNode, kinds));
-		}, initialValue);
-	}
-
-}

src/parsers/directive.parser.ts

@@ -1,83 +1,180 @@
+import {
+	parseTemplate,
+	TmplAstNode as Node,
+	TmplAstElement as Element,
+	TmplAstText as Text,
+	TmplAstTemplate as Template,
+	TmplAstTextAttribute as TextAttribute,
+	TmplAstBoundAttribute as BoundAttribute,
+	AST,
+	ASTWithSource,
+	LiteralPrimitive,
+	Conditional,
+	Binary,
+	BindingPipe,
+	Interpolation,
+	LiteralArray,
+	LiteralMap
+} from '@angular/compiler';
+
 import { ParserInterface } from './parser.interface';
 import { TranslationCollection } from '../utils/translation.collection';
 import { isPathAngularComponent, extractComponentInlineTemplate } from '../utils/utils';
 
-import { parseTemplate, TmplAstNode, TmplAstElement, TmplAstTextAttribute } from '@angular/compiler';
+const TRANSLATE_ATTR_NAME = 'translate';
+type ElementLike = Element | Template;
 
 export class DirectiveParser implements ParserInterface {
-
-	public extract(template: string, path: string): TranslationCollection {
-		if (path && isPathAngularComponent(path)) {
-			template = extractComponentInlineTemplate(template);
-		}
-
+	public extract(source: string, filePath: string): TranslationCollection | null {
 		let collection: TranslationCollection = new TranslationCollection();
 
-		const nodes: TmplAstNode[] = this.parseTemplate(template, path);
-		this.getTranslatableElements(nodes).forEach(element => {
-			const key = this.getElementTranslateAttrValue(element) || this.getElementContents(element);
-			collection = collection.add(key);
-		});
+		if (filePath && isPathAngularComponent(filePath)) {
+			source = extractComponentInlineTemplate(source);
+		}
+		const nodes: Node[] = this.parseTemplate(source, filePath);
+		const elements: ElementLike[] = this.getElementsWithTranslateAttribute(nodes);
 
+		elements.forEach((element) => {
+			const attribute = this.getAttribute(element, TRANSLATE_ATTR_NAME);
+			if (attribute?.value) {
+				collection = collection.add(attribute.value);
+				return;
+			}
+
+			const boundAttribute = this.getBoundAttribute(element, TRANSLATE_ATTR_NAME);
+			if (boundAttribute?.value) {
+				this.getLiteralPrimitives(boundAttribute.value).forEach((literalPrimitive) => {
+					collection = collection.add(literalPrimitive.value);
+				});
+				return;
+			}
+
+			const textNodes = this.getTextNodes(element);
+			textNodes.forEach((textNode) => {
+				collection = collection.add(textNode.value.trim());
+			});
+		});
 		return collection;
 	}
 
-	protected getTranslatableElements(nodes: TmplAstNode[]): TmplAstElement[] {
-		return nodes
-			.filter(element => this.isElement(element))
-			.reduce((result: TmplAstElement[], element: TmplAstElement) => {
-				return result.concat(this.findChildrenElements(element));
-			}, [])
-			.filter(element => this.isTranslatable(element));
+	/**
+	 * Find all ElementLike nodes with a translate attribute
+	 * @param nodes
+	 */
+	protected getElementsWithTranslateAttribute(nodes: Node[]): ElementLike[] {
+		let elements: ElementLike[] = [];
+		nodes.filter(this.isElementLike).forEach((element) => {
+			if (this.hasAttribute(element, TRANSLATE_ATTR_NAME)) {
+				elements = [...elements, element];
+			}
+			if (this.hasBoundAttribute(element, TRANSLATE_ATTR_NAME)) {
+				elements = [...elements, element];
+			}
+			const childElements = this.getElementsWithTranslateAttribute(element.children);
+			if (childElements.length) {
+				elements = [...elements, ...childElements];
+			}
+		});
+		return elements;
 	}
 
-	protected findChildrenElements(node: TmplAstNode): TmplAstElement[] {
-		if (!this.isElement(node)) {
-			return [];
+	/**
+	 * Get direct child nodes of type Text
+	 * @param element
+	 */
+	protected getTextNodes(element: ElementLike): Text[] {
+		return element.children.filter(this.isText);
 	}
 
-		// If element has translate attribute all its contents is translatable
-		// so we don't need to traverse any deeper
-		if (this.isTranslatable(node)) {
-			return [node];
+	/**
+	 * Check if attribute is present on element
+	 * @param element
+	 */
+	protected hasAttribute(element: ElementLike, name: string): boolean {
+		return this.getAttribute(element, name) !== undefined;
 	}
 
-		return node.children.reduce((result: TmplAstElement[], childNode: TmplAstNode) => {
-			if (this.isElement(childNode)) {
-				const children = this.findChildrenElements(childNode);
-				return result.concat(children);
-			}
-			return result;
-		}, [node]);
+	/**
+	 * Get attribute value if present on element
+	 * @param element
+	 */
+	protected getAttribute(element: ElementLike, name: string): TextAttribute {
+		return element.attributes.find((attribute) => attribute.name === name);
 	}
 
-	protected parseTemplate(template: string, path: string): TmplAstNode[] {
+	/**
+	 * Check if bound attribute is present on element
+	 * @param element
+	 * @param name
+	 */
+	protected hasBoundAttribute(element: ElementLike, name: string): boolean {
+		return this.getBoundAttribute(element, name) !== undefined;
+	}
+
+	/**
+	 * Get bound attribute if present on element
+	 * @param element
+	 * @param name
+	 */
+	protected getBoundAttribute(element: ElementLike, name: string): BoundAttribute {
+		return element.inputs.find((input) => input.name === name);
+	}
+
+	/**
+	 * Get literal primitives from expression
+	 * @param exp
+	 */
+	protected getLiteralPrimitives(exp: AST): LiteralPrimitive[] {
+		if (exp instanceof LiteralPrimitive) {
+			return [exp];
+		}
+
+		let visit: AST[] = [];
+		if (exp instanceof Interpolation) {
+			visit = exp.expressions;
+		} else if (exp instanceof LiteralArray) {
+			visit = exp.expressions;
+		} else if (exp instanceof LiteralMap) {
+			visit = exp.values;
+		} else if (exp instanceof BindingPipe) {
+			visit = [exp.exp];
+		} else if (exp instanceof Conditional) {
+			visit = [exp.trueExp, exp.falseExp];
+		} else if (exp instanceof Binary) {
+			visit = [exp.left, exp.right];
+		} else if (exp instanceof ASTWithSource) {
+			visit = [exp.ast];
+		}
+
+		let results: LiteralPrimitive[] = [];
+		visit.forEach((child) => {
+			results = [...results, ...this.getLiteralPrimitives(child)];
+		});
+		return results;
+	}
+
+	/**
+	 * Check if node type is ElementLike
+	 * @param node
+	 */
+	protected isElementLike(node: Node): node is ElementLike {
+		return node instanceof Element || node instanceof Template;
+	}
+
+	/**
+	 * Check if node type is Text
+	 * @param node
+	 */
+	protected isText(node: Node): node is Text {
+		return node instanceof Text;
+	}
+
+	/**
+	 * Parse a template into nodes
+	 * @param template
+	 * @param path
+	 */
+	protected parseTemplate(template: string, path: string): Node[] {
 		return parseTemplate(template, path).nodes;
 	}
-
-	protected isElement(node: any): node is TmplAstElement {
-		return node
-			&& node.attributes !== undefined
-			&& node.children !== undefined;
-	}
-
-	protected isTranslatable(node: TmplAstNode): boolean {
-		if (this.isElement(node) && node.attributes.some(attribute => attribute.name === 'translate')) {
-			return true;
-		}
-		return false;
-	}
-
-	protected getElementTranslateAttrValue(element: TmplAstElement): string {
-		const attr: TmplAstTextAttribute = element.attributes.find(attribute => attribute.name === 'translate');
-		return attr && attr.value || '';
-	}
-
-	protected getElementContents(element: TmplAstElement): string {
-		const contents = element.sourceSpan.start.file.content;
-		const start = element.startSourceSpan.end.offset;
-		const end = element.endSourceSpan.start.offset;
-		return contents.substring(start, end).trim();
-	}
-
 }

src/parsers/function.parser.ts

@@ -1,60 +0,0 @@
-import { Node, CallExpression, SyntaxKind, Identifier } from 'typescript';
-
-import { ParserInterface } from './parser.interface';
-import { AbstractAstParser } from './abstract-ast.parser';
-import { TranslationCollection } from '../utils/translation.collection';
-
-export class FunctionParser extends AbstractAstParser implements ParserInterface {
-
-	protected functionIdentifier: string = 'marker';
-
-	public constructor(options?: any) {
-		super();
-		if (options && typeof options.identifier !== 'undefined') {
-			this.functionIdentifier = options.identifier;
-		}
-	}
-
-	public extract(template: string, path: string): TranslationCollection {
-		let collection: TranslationCollection = new TranslationCollection();
-
-		this.sourceFile = this.createSourceFile(path, template);
-
-		const callNodes = this.findCallNodes();
-		callNodes.forEach(callNode => {
-			const keys: string[] = this.getStringLiterals(callNode);
-			if (keys && keys.length) {
-				collection = collection.addKeys(keys);
-			}
-		});
-		return collection;
-	}
-
-	/**
-	 * Find all calls to marker function
-	 */
-	protected findCallNodes(node?: Node): CallExpression[] {
-		if (!node) {
-			node = this.sourceFile;
-		}
-
-		let callNodes = this.findNodes(node, [SyntaxKind.CallExpression]) as CallExpression[];
-		callNodes = callNodes
-			.filter(callNode => {
-				// Only call expressions with arguments
-				if (callNode.arguments.length < 1) {
-					return false;
-				}
-
-				const identifier = (callNode.getChildAt(0) as Identifier).text;
-				if (identifier !== this.functionIdentifier) {
-					return false;
-				}
-
-				return true;
-			});
-
-		return callNodes;
-	}
-
-}

src/parsers/marker.parser.ts

@@ -0,0 +1,32 @@
+import { tsquery } from '@phenomnomnominal/tsquery';
+
+import { ParserInterface } from './parser.interface';
+import { TranslationCollection } from '../utils/translation.collection';
+import { getNamedImportAlias, findFunctionCallExpressions, getStringsFromExpression } from '../utils/ast-helpers';
+
+const MARKER_MODULE_NAME = '@biesbjerg/ngx-translate-extract-marker';
+const MARKER_IMPORT_NAME = 'marker';
+
+export class MarkerParser implements ParserInterface {
+	public extract(source: string, filePath: string): TranslationCollection | null {
+		const sourceFile = tsquery.ast(source, filePath);
+
+		const markerImportName = getNamedImportAlias(sourceFile, MARKER_MODULE_NAME, MARKER_IMPORT_NAME);
+		if (!markerImportName) {
+			return null;
+		}
+
+		let collection: TranslationCollection = new TranslationCollection();
+
+		const callExpressions = findFunctionCallExpressions(sourceFile, markerImportName);
+		callExpressions.forEach((callExpression) => {
+			const [firstArg] = callExpression.arguments;
+			if (!firstArg) {
+				return;
+			}
+			const strings = getStringsFromExpression(firstArg);
+			collection = collection.addKeys(strings);
+		});
+		return collection;
+	}
+}

src/parsers/parser.interface.ts

@@ -1,7 +1,5 @@
 import { TranslationCollection } from '../utils/translation.collection';
 
 export interface ParserInterface {
-
-	extract(template: string, path: string): TranslationCollection;
-
+	extract(source: string, filePath: string): TranslationCollection | null;
 }

src/parsers/pipe.parser.ts

@@ -1,27 +1,163 @@
+import {
+	AST,
+	TmplAstNode,
+	parseTemplate,
+	BindingPipe,
+	LiteralPrimitive,
+	Conditional,
+	TmplAstTextAttribute,
+	Binary,
+	LiteralMap,
+	LiteralArray,
+	Interpolation,
+	MethodCall
+} from '@angular/compiler';
+
 import { ParserInterface } from './parser.interface';
 import { TranslationCollection } from '../utils/translation.collection';
 import { isPathAngularComponent, extractComponentInlineTemplate } from '../utils/utils';
 
+const TRANSLATE_PIPE_NAME = 'translate';
+
 export class PipeParser implements ParserInterface {
-
-	public extract(template: string, path: string): TranslationCollection {
-		if (path && isPathAngularComponent(path)) {
-			template = extractComponentInlineTemplate(template);
+	public extract(source: string, filePath: string): TranslationCollection | null {
+		if (filePath && isPathAngularComponent(filePath)) {
+			source = extractComponentInlineTemplate(source);
 		}
 
-		return this.parseTemplate(template);
-	}
-
-	protected parseTemplate(template: string): TranslationCollection {
 		let collection: TranslationCollection = new TranslationCollection();
-
-		const regExp: RegExp = /(['"`])((?:(?!\1).|\\\1)+)\1\s*\|\s*translate/g;
-		let matches: RegExpExecArray;
-		while (matches = regExp.exec(template)) {
-			collection = collection.add(matches[2].split('\\\'').join('\''));
-		}
-
+		const nodes: TmplAstNode[] = this.parseTemplate(source, filePath);
+		const pipes: BindingPipe[] = nodes.map((node) => this.findPipesInNode(node)).flat();
+		pipes.forEach((pipe) => {
+			this.parseTranslationKeysFromPipe(pipe).forEach((key: string) => {
+				collection = collection.add(key);
+			});
+		});
 		return collection;
 	}
 
+	protected findPipesInNode(node: any): BindingPipe[] {
+		let ret: BindingPipe[] = [];
+
+		if (node?.children) {
+			ret = node.children.reduce(
+				(result: BindingPipe[], childNode: TmplAstNode) => {
+					const children = this.findPipesInNode(childNode);
+					return result.concat(children);
+				},
+				[ret]
+			);
+		}
+
+		if (node?.value?.ast) {
+			ret.push(...this.getTranslatablesFromAst(node.value.ast));
+		}
+
+		if (node?.attributes) {
+			const translateableAttributes = node.attributes.filter((attr: TmplAstTextAttribute) => {
+				return attr.name === TRANSLATE_PIPE_NAME;
+			});
+			ret = [...ret, ...translateableAttributes];
+		}
+
+		if (node?.inputs) {
+			node.inputs.forEach((input: any) => {
+				// <element [attrib]="'identifier' | translate">
+				if (input?.value?.ast) {
+					ret.push(...this.getTranslatablesFromAst(input.value.ast));
+				}
+			});
+		}
+
+		return ret;
+	}
+
+	protected parseTranslationKeysFromPipe(pipeContent: BindingPipe | LiteralPrimitive | Conditional): string[] {
+		const ret: string[] = [];
+		if (pipeContent instanceof LiteralPrimitive) {
+			ret.push(pipeContent.value);
+		} else if (pipeContent instanceof Conditional) {
+			const trueExp: LiteralPrimitive | Conditional = pipeContent.trueExp as any;
+			ret.push(...this.parseTranslationKeysFromPipe(trueExp));
+			const falseExp: LiteralPrimitive | Conditional = pipeContent.falseExp as any;
+			ret.push(...this.parseTranslationKeysFromPipe(falseExp));
+		} else if (pipeContent instanceof BindingPipe) {
+			ret.push(...this.parseTranslationKeysFromPipe(pipeContent.exp as any));
+		}
+		return ret;
+	}
+
+	protected getTranslatablesFromAst(ast: AST): BindingPipe[] {
+		// the entire expression is the translate pipe, e.g.:
+		// - 'foo' | translate
+		// - (condition ? 'foo' : 'bar') | translate
+		if (this.expressionIsOrHasBindingPipe(ast)) {
+			return [ast];
+		}
+
+		// angular double curly bracket interpolation, e.g.:
+		// - {{ expressions }}
+		if (ast instanceof Interpolation) {
+			return this.getTranslatablesFromAsts(ast.expressions);
+		}
+
+		// ternary operator, e.g.:
+		// - condition ? null : ('foo' | translate)
+		// - condition ? ('foo' | translate) : null
+		if (ast instanceof Conditional) {
+			return this.getTranslatablesFromAsts([ast.trueExp, ast.falseExp]);
+		}
+
+		// string concatenation, e.g.:
+		// - 'foo' + 'bar' + ('baz' | translate)
+		if (ast instanceof Binary) {
+			return this.getTranslatablesFromAsts([ast.left, ast.right]);
+		}
+
+		// a pipe on the outer expression, but not the translate pipe - ignore the pipe, visit the expression, e.g.:
+		// - { foo: 'Hello' | translate } | json
+		if (ast instanceof BindingPipe) {
+			return this.getTranslatablesFromAst(ast.exp);
+		}
+
+		// object - ignore the keys, visit all values, e.g.:
+		// - { key1: 'value1' | translate, key2: 'value2' | translate }
+		if (ast instanceof LiteralMap) {
+			return this.getTranslatablesFromAsts(ast.values);
+		}
+
+		// array - visit all its values, e.g.:
+		// - [ 'value1' | translate, 'value2' | translate ]
+		if (ast instanceof LiteralArray) {
+			return this.getTranslatablesFromAsts(ast.expressions);
+		}
+
+		if (ast instanceof MethodCall) {
+			return this.getTranslatablesFromAsts(ast.args);
+		}
+
+		return [];
+	}
+
+	protected getTranslatablesFromAsts(asts: AST[]): BindingPipe[] {
+		return this.flatten(asts.map((ast) => this.getTranslatablesFromAst(ast)));
+	}
+
+	protected flatten<T extends AST>(array: T[][]): T[] {
+		return [].concat(...array);
+	}
+
+	protected expressionIsOrHasBindingPipe(exp: any): exp is BindingPipe {
+		if (exp.name && exp.name === TRANSLATE_PIPE_NAME) {
+			return true;
+		}
+		if (exp.exp && exp.exp instanceof BindingPipe) {
+			return this.expressionIsOrHasBindingPipe(exp.exp);
+		}
+		return false;
+	}
+
+	protected parseTemplate(template: string, path: string): TmplAstNode[] {
+		return parseTemplate(template, path).nodes;
+	}
 }

src/parsers/service.parser.ts

@@ -1,142 +1,64 @@
-import {
-	SourceFile,
-	Node,
-	ConstructorDeclaration,
-	Identifier,
-	TypeReferenceNode,
-	ClassDeclaration,
-	SyntaxKind,
-	CallExpression,
-	PropertyAccessExpression,
-	isPropertyAccessExpression
-} from 'typescript';
+import { ClassDeclaration, CallExpression } from 'typescript';
+import { tsquery } from '@phenomnomnominal/tsquery';
 
 import { ParserInterface } from './parser.interface';
-import { AbstractAstParser } from './abstract-ast.parser';
 import { TranslationCollection } from '../utils/translation.collection';
+import {
+	findClassDeclarations,
+	findClassPropertyByType,
+	findPropertyCallExpressions,
+	findMethodCallExpressions,
+	getStringsFromExpression,
+	findMethodParameterByType,
+	findConstructorDeclaration
+} from '../utils/ast-helpers';
 
-export class ServiceParser extends AbstractAstParser implements ParserInterface {
+const TRANSLATE_SERVICE_TYPE_REFERENCE = 'TranslateService';
+const TRANSLATE_SERVICE_METHOD_NAMES = ['get', 'instant', 'stream'];
 
-	protected sourceFile: SourceFile;
+export class ServiceParser implements ParserInterface {
+	public extract(source: string, filePath: string): TranslationCollection | null {
+		const sourceFile = tsquery.ast(source, filePath);
 
-	public extract(template: string, path: string): TranslationCollection {
-		let collection: TranslationCollection = new TranslationCollection();
-
-		this.sourceFile = this.createSourceFile(path, template);
-		const classNodes = this.findClassNodes(this.sourceFile);
-		classNodes.forEach(classNode => {
-			const constructorNode = this.findConstructorNode(classNode);
-			if (!constructorNode) {
-				return;
-			}
-
-			const propertyName: string = this.findTranslateServicePropertyName(constructorNode);
-			if (!propertyName) {
-				return;
-			}
-
-			const callNodes = this.findCallNodes(classNode, propertyName);
-			callNodes.forEach(callNode => {
-				const keys: string[] = this.getStringLiterals(callNode);
-				if (keys && keys.length) {
-					collection = collection.addKeys(keys);
-				}
-			});
-		});
-
-		return collection;
-	}
-
-	/**
-	 * Detect what the TranslateService instance property
-	 * is called by inspecting constructor arguments
-	 */
-	protected findTranslateServicePropertyName(constructorNode: ConstructorDeclaration): string {
-		if (!constructorNode) {
+		const classDeclarations = findClassDeclarations(sourceFile);
+		if (!classDeclarations) {
 			return null;
 		}
 
-		const result = constructorNode.parameters.find(parameter => {
-			// Skip if visibility modifier is not present (we want it set as an instance property)
-			if (!parameter.modifiers) {
-				return false;
-			}
+		let collection: TranslationCollection = new TranslationCollection();
 
-			// Parameter has no type
-			if (!parameter.type) {
-				return false;
-			}
+		classDeclarations.forEach((classDeclaration) => {
+			const callExpressions = [
+				...this.findConstructorParamCallExpressions(classDeclaration),
+				...this.findPropertyCallExpressions(classDeclaration)
+			];
 
-			// Make sure className is of the correct type
-			const parameterType: Identifier = (parameter.type as TypeReferenceNode).typeName as Identifier;
-			if (!parameterType) {
-				return false;
+			callExpressions.forEach((callExpression) => {
+				const [firstArg] = callExpression.arguments;
+				if (!firstArg) {
+					return;
 				}
-			const className: string = parameterType.text;
-			if (className !== 'TranslateService') {
-				return false;
-			}
-
-			return true;
+				const strings = getStringsFromExpression(firstArg);
+				collection = collection.addKeys(strings);
 			});
-
-		if (result) {
-			return (result.name as Identifier).text;
-		}
-	}
-
-	/**
-	 * Find class nodes
-	 */
-	protected findClassNodes(node: Node): ClassDeclaration[] {
-		return this.findNodes(node, [SyntaxKind.ClassDeclaration]) as ClassDeclaration[];
-	}
-
-	/**
-	 * Find constructor
-	 */
-	protected findConstructorNode(node: ClassDeclaration): ConstructorDeclaration {
-		const constructorNodes = this.findNodes(node, [SyntaxKind.Constructor]) as ConstructorDeclaration[];
-		if (constructorNodes) {
-			return constructorNodes[0];
-		}
-	}
-
-	/**
-	 * Find all calls to TranslateService methods
-	 */
-	protected findCallNodes(node: Node, propertyIdentifier: string): CallExpression[] {
-		let callNodes = this.findNodes(node, [SyntaxKind.CallExpression]) as CallExpression[];
-		callNodes = callNodes
-			.filter(callNode => {
-				// Only call expressions with arguments
-				if (callNode.arguments.length < 1) {
-					return false;
-				}
-
-				const propAccess = callNode.getChildAt(0).getChildAt(0) as PropertyAccessExpression;
-				if (!propAccess || !isPropertyAccessExpression(propAccess)) {
-					return false;
-				}
-				if (!propAccess.getFirstToken() || propAccess.getFirstToken().kind !== SyntaxKind.ThisKeyword) {
-					return false;
-				}
-				if (propAccess.name.text !== propertyIdentifier) {
-					return false;
-				}
-
-				const methodAccess = callNode.getChildAt(0) as PropertyAccessExpression;
-				if (!methodAccess || methodAccess.kind !== SyntaxKind.PropertyAccessExpression) {
-					return false;
-				}
-				if (!methodAccess.name || (methodAccess.name.text !== 'get' && methodAccess.name.text !== 'instant' && methodAccess.name.text !== 'stream')) {
-					return false;
-				}
-
-				return true;
 		});
-
-		return callNodes;
+		return collection;
 	}
 
+	protected findConstructorParamCallExpressions(classDeclaration: ClassDeclaration): CallExpression[] {
+		const constructorDeclaration = findConstructorDeclaration(classDeclaration);
+		if (!constructorDeclaration) {
+			return [];
+		}
+		const paramName = findMethodParameterByType(constructorDeclaration, TRANSLATE_SERVICE_TYPE_REFERENCE);
+		return findMethodCallExpressions(constructorDeclaration, paramName, TRANSLATE_SERVICE_METHOD_NAMES);
+	}
+
+	protected findPropertyCallExpressions(classDeclaration: ClassDeclaration): CallExpression[] {
+		const propName: string = findClassPropertyByType(classDeclaration, TRANSLATE_SERVICE_TYPE_REFERENCE);
+		if (!propName) {
+			return [];
+		}
+		return findPropertyCallExpressions(classDeclaration, propName, TRANSLATE_SERVICE_METHOD_NAMES);
+	}
 }

src/post-processors/key-as-default-value.post-processor.ts

@@ -2,11 +2,9 @@ import { TranslationCollection } from '../utils/translation.collection';
 import { PostProcessorInterface } from './post-processor.interface';
 
 export class KeyAsDefaultValuePostProcessor implements PostProcessorInterface {
-
 	public name: string = 'KeyAsDefaultValue';
 
 	public process(draft: TranslationCollection, extracted: TranslationCollection, existing: TranslationCollection): TranslationCollection {
-		return draft.map((key, val) => val === '' ? key : val);
+		return draft.map((key, val) => (val === '' ? key : val));
 	}
-
 }

src/post-processors/null-as-default-value.post-processor.ts

@@ -0,0 +1,10 @@
+import { TranslationCollection } from '../utils/translation.collection';
+import { PostProcessorInterface } from './post-processor.interface';
+
+export class NullAsDefaultValuePostProcessor implements PostProcessorInterface {
+	public name: string = 'NullAsDefaultValue';
+
+	public process(draft: TranslationCollection, extracted: TranslationCollection, existing: TranslationCollection): TranslationCollection {
+		return draft.map((key, val) => (existing.get(key) === undefined ? null : val));
+	}
+}

src/post-processors/post-processor.interface.ts

@@ -1,9 +1,7 @@
 import { TranslationCollection } from '../utils/translation.collection';
 
 export interface PostProcessorInterface {
-
 	name: string;
 
 	process(draft: TranslationCollection, extracted: TranslationCollection, existing: TranslationCollection): TranslationCollection;
-
 }

src/post-processors/purge-obsolete-keys.post-processor.ts

@@ -2,11 +2,9 @@ import { TranslationCollection } from '../utils/translation.collection';
 import { PostProcessorInterface } from './post-processor.interface';
 
 export class PurgeObsoleteKeysPostProcessor implements PostProcessorInterface {
-
 	public name: string = 'PurgeObsoleteKeys';
 
 	public process(draft: TranslationCollection, extracted: TranslationCollection, existing: TranslationCollection): TranslationCollection {
 		return draft.intersect(extracted);
 	}
-
 }

src/post-processors/sort-by-key.post-processor.ts

@@ -2,11 +2,9 @@ import { TranslationCollection } from '../utils/translation.collection';
 import { PostProcessorInterface } from './post-processor.interface';
 
 export class SortByKeyPostProcessor implements PostProcessorInterface {
-
 	public name: string = 'SortByKey';
 
 	public process(draft: TranslationCollection, extracted: TranslationCollection, existing: TranslationCollection): TranslationCollection {
 		return draft.sort();
 	}
-
 }

src/post-processors/string-as-default-value.post-processor.ts

@@ -0,0 +1,16 @@
+import { TranslationCollection } from '../utils/translation.collection';
+import { PostProcessorInterface } from './post-processor.interface';
+
+interface Options {
+	defaultValue: string;
+}
+
+export class StringAsDefaultValuePostProcessor implements PostProcessorInterface {
+	public name: string = 'StringAsDefaultValue';
+
+	public constructor(protected options: Options) {}
+
+	public process(draft: TranslationCollection, extracted: TranslationCollection, existing: TranslationCollection): TranslationCollection {
+		return draft.map((key, val) => (existing.get(key) === undefined ? this.options.defaultValue : val));
+	}
+}

src/utils/ast-helpers.ts

@@ -0,0 +1,157 @@
+import { tsquery } from '@phenomnomnominal/tsquery';
+import {
+	SyntaxKind,
+	Node,
+	NamedImports,
+	Identifier,
+	ClassDeclaration,
+	ConstructorDeclaration,
+	isStringLiteralLike,
+	isArrayLiteralExpression,
+	CallExpression,
+	Expression,
+	isBinaryExpression,
+	isConditionalExpression,
+	PropertyAccessExpression
+} from 'typescript';
+
+export function getNamedImports(node: Node, moduleName: string): NamedImports[] {
+	const query = `ImportDeclaration[moduleSpecifier.text="${moduleName}"] NamedImports`;
+	return tsquery<NamedImports>(node, query);
+}
+
+export function getNamedImportAlias(node: Node, moduleName: string, importName: string): string | null {
+	const [namedImportNode] = getNamedImports(node, moduleName);
+	if (!namedImportNode) {
+		return null;
+	}
+
+	const query = `ImportSpecifier:has(Identifier[name="${importName}"]) > Identifier`;
+	const identifiers = tsquery<Identifier>(namedImportNode, query);
+	if (identifiers.length === 1) {
+		return identifiers[0].text;
+	}
+	if (identifiers.length > 1) {
+		return identifiers[identifiers.length - 1].text;
+	}
+	return null;
+}
+
+export function findClassDeclarations(node: Node): ClassDeclaration[] {
+	const query = 'ClassDeclaration';
+	return tsquery<ClassDeclaration>(node, query);
+}
+
+export function findClassPropertyByType(node: ClassDeclaration, type: string): string | null {
+	return findClassPropertyConstructorParameterByType(node, type) || findClassPropertyDeclarationByType(node, type);
+}
+
+export function findConstructorDeclaration(node: ClassDeclaration): ConstructorDeclaration {
+	const query = `Constructor`;
+	const [result] = tsquery<ConstructorDeclaration>(node, query);
+	return result;
+}
+
+export function findMethodParameterByType(node: Node, type: string): string | null {
+	const query = `Parameter:has(TypeReference > Identifier[name="${type}"]) > Identifier`;
+	const [result] = tsquery<Identifier>(node, query);
+	if (result) {
+		return result.text;
+	}
+	return null;
+}
+
+export function findMethodCallExpressions(node: Node, propName: string, fnName: string | string[]): CallExpression[] {
+	if (Array.isArray(fnName)) {
+		fnName = fnName.join('|');
+	}
+	const query = `CallExpression > PropertyAccessExpression:has(Identifier[name=/^(${fnName})$/]):has(PropertyAccessExpression:has(Identifier[name="${propName}"]):not(:has(ThisKeyword)))`;
+	const nodes = tsquery<PropertyAccessExpression>(node, query).map((n) => n.parent as CallExpression);
+	return nodes;
+}
+
+export function findClassPropertyConstructorParameterByType(node: ClassDeclaration, type: string): string | null {
+	const query = `Constructor Parameter:has(TypeReference > Identifier[name="${type}"]):has(PublicKeyword,ProtectedKeyword,PrivateKeyword) > Identifier`;
+	const [result] = tsquery<Identifier>(node, query);
+	if (result) {
+		return result.text;
+	}
+	return null;
+}
+
+export function findClassPropertyDeclarationByType(node: ClassDeclaration, type: string): string | null {
+	const query = `PropertyDeclaration:has(TypeReference > Identifier[name="${type}"]) > Identifier`;
+	const [result] = tsquery<Identifier>(node, query);
+	if (result) {
+		return result.text;
+	}
+	return null;
+}
+
+export function findFunctionCallExpressions(node: Node, fnName: string | string[]): CallExpression[] {
+	if (Array.isArray(fnName)) {
+		fnName = fnName.join('|');
+	}
+	const query = `CallExpression:has(Identifier[name="${fnName}"]):not(:has(PropertyAccessExpression))`;
+	const nodes = tsquery<CallExpression>(node, query);
+	return nodes;
+}
+
+export function findPropertyCallExpressions(node: Node, prop: string, fnName: string | string[]): CallExpression[] {
+	if (Array.isArray(fnName)) {
+		fnName = fnName.join('|');
+	}
+	const query = `CallExpression > PropertyAccessExpression:has(Identifier[name=/^(${fnName})$/]):has(PropertyAccessExpression:has(Identifier[name="${prop}"]):has(ThisKeyword))`;
+	const nodes = tsquery<PropertyAccessExpression>(node, query).map((n) => n.parent as CallExpression);
+	return nodes;
+}
+
+export function getStringsFromExpression(expression: Expression): string[] {
+	if (isStringLiteralLike(expression)) {
+		return [expression.text];
+	}
+
+	if (isArrayLiteralExpression(expression)) {
+		return expression.elements.reduce((result: string[], element: Expression) => {
+			const strings = getStringsFromExpression(element);
+			return [...result, ...strings];
+		}, []);
+	}
+
+	if (isBinaryExpression(expression)) {
+		const [left] = getStringsFromExpression(expression.left);
+		const [right] = getStringsFromExpression(expression.right);
+
+		if (expression.operatorToken.kind === SyntaxKind.PlusToken) {
+			if (typeof left === 'string' && typeof right === 'string') {
+				return [left + right];
+			}
+		}
+
+		if (expression.operatorToken.kind === SyntaxKind.BarBarToken) {
+			const result = [];
+			if (typeof left === 'string') {
+				result.push(left);
+			}
+			if (typeof right === 'string') {
+				result.push(right);
+			}
+			return result;
+		}
+	}
+
+	if (isConditionalExpression(expression)) {
+		const [whenTrue] = getStringsFromExpression(expression.whenTrue);
+		const [whenFalse] = getStringsFromExpression(expression.whenFalse);
+
+		const result = [];
+		if (typeof whenTrue === 'string') {
+			result.push(whenTrue);
+		}
+		if (typeof whenFalse === 'string') {
+			result.push(whenFalse);
+		}
+		return result;
+	}
+	return [];
+}

src/utils/fs-helpers.ts

@@ -0,0 +1,36 @@
+import * as os from 'os';
+import * as fs from 'fs';
+import * as braces from 'braces';
+
+declare module 'braces' {
+	interface Options {
+		keepEscaping?: boolean; // Workaround for option not present in @types/braces 3.0.0
+	}
+}
+
+export function normalizeHomeDir(path: string): string {
+	if (path.substring(0, 1) === '~') {
+		return `${os.homedir()}/${path.substring(1)}`;
+	}
+	return path;
+}
+
+export function expandPattern(pattern: string): string[] {
+	return braces(pattern, { expand: true, keepEscaping: true });
+}
+
+export function normalizePaths(patterns: string[], defaultPatterns: string[] = []): string[] {
+	return patterns
+		.map((pattern) =>
+			expandPattern(pattern)
+				.map((path) => {
+					path = normalizeHomeDir(path);
+					if (fs.existsSync(path) && fs.statSync(path).isDirectory()) {
+						return defaultPatterns.map((defaultPattern) => path + defaultPattern);
+					}
+					return path;
+				})
+				.flat()
+		)
+		.flat();
+}

src/utils/translation.collection.ts

@@ -3,7 +3,6 @@ export interface TranslationType {
 }
 
 export class TranslationCollection {
-
 	public values: TranslationType = {};
 
 	public constructor(values: TranslationType = {}) {
@@ -16,24 +15,23 @@ export class TranslationCollection {
 
 	public addKeys(keys: string[]): TranslationCollection {
 		const values = keys.reduce((results, key) => {
-			results[key] = '';
-			return results;
+			return { ...results, [key]: '' };
 		}, {} as TranslationType);
 		return new TranslationCollection({ ...this.values, ...values });
 	}
 
 	public remove(key: string): TranslationCollection {
-		return this.filter(k => key !== k);
+		return this.filter((k) => key !== k);
 	}
 
 	public forEach(callback: (key?: string, val?: string) => void): TranslationCollection {
-		Object.keys(this.values).forEach(key => callback.call(this, key, this.values[key]));
+		Object.keys(this.values).forEach((key) => callback.call(this, key, this.values[key]));
 		return this;
 	}
 
 	public filter(callback: (key?: string, val?: string) => boolean): TranslationCollection {
-		let values: TranslationType = {};
-		this.forEach((key: string, val: string) => {
+		const values: TranslationType = {};
+		this.forEach((key, val) => {
 			if (callback.call(this, key, val)) {
 				values[key] = val;
 			}
@@ -42,8 +40,8 @@ export class TranslationCollection {
 	}
 
 	public map(callback: (key?: string, val?: string) => string): TranslationCollection {
-		let values: TranslationType = {};
-		this.forEach((key: string, val: string) => {
+		const values: TranslationType = {};
+		this.forEach((key, val) => {
 			values[key] = callback.call(this, key, val);
 		});
 		return new TranslationCollection(values);
@@ -54,9 +52,8 @@ export class TranslationCollection {
 	}
 
 	public intersect(collection: TranslationCollection): TranslationCollection {
-		let values: TranslationType = {};
-		this.filter(key => collection.has(key))
-			.forEach((key: string, val: string) => {
+		const values: TranslationType = {};
+		this.filter((key) => collection.has(key)).forEach((key, val) => {
 			values[key] = val;
 		});
 
@@ -84,8 +81,10 @@ export class TranslationCollection {
 	}
 
 	public sort(compareFn?: (a: string, b: string) => number): TranslationCollection {
-		let values: TranslationType = {};
-		this.keys().sort(compareFn).forEach((key) => {
+		const values: TranslationType = {};
+		this.keys()
+			.sort(compareFn)
+			.forEach((key) => {
 				values[key] = this.get(key);
 			});
 

src/utils/utils.ts

@@ -2,7 +2,7 @@
  * Assumes file is an Angular component if type is javascript/typescript
  */
 export function isPathAngularComponent(path: string): boolean {
-	return (/\.ts|js$/i).test(path);
+	return /\.ts|js$/i.test(path);
 }
 
 /**

tests/compilers/namespaced-json.compiler.spec.ts

@@ -4,7 +4,6 @@ import { TranslationCollection } from '../../src/utils/translation.collection';
 import { NamespacedJsonCompiler } from '../../src/compilers/namespaced-json.compiler';
 
 describe('NamespacedJsonCompiler', () => {
-
 	let compiler: NamespacedJsonCompiler;
 
 	beforeEach(() => {
@@ -23,7 +22,10 @@ describe('NamespacedJsonCompiler', () => {
 			}
 		`;
 		const collection: TranslationCollection = compiler.parse(contents);
-		expect(collection.values).to.deep.equal({'NAMESPACE.KEY.FIRST_KEY': '', 'NAMESPACE.KEY.SECOND_KEY': 'VALUE' });
+		expect(collection.values).to.deep.equal({
+			'NAMESPACE.KEY.FIRST_KEY': '',
+			'NAMESPACE.KEY.SECOND_KEY': 'VALUE'
+		});
 	});
 
 	it('should unflatten keys on compile', () => {
@@ -59,11 +61,10 @@ describe('NamespacedJsonCompiler', () => {
 
 	it('should not reorder keys when compiled', () => {
 		const collection = new TranslationCollection({
-			'BROWSE': '',
-			'LOGIN': ''
+			BROWSE: '',
+			LOGIN: ''
 		});
 		const result: string = compiler.compile(collection);
 		expect(result).to.equal('{\n\t"BROWSE": "",\n\t"LOGIN": ""\n}');
 	});
-
 });

tests/compilers/po.compiler.spec.ts

@@ -0,0 +1,24 @@
+import { expect } from 'chai';
+
+import { TranslationCollection } from '../../src/utils/translation.collection';
+import { PoCompiler } from '../../src/compilers/po.compiler';
+
+describe('PoCompiler', () => {
+	let compiler: PoCompiler;
+
+	beforeEach(() => {
+		compiler = new PoCompiler();
+	});
+
+	it('should still include html ', () => {
+		const collection = new TranslationCollection({
+			'A <strong>test</strong>': 'Un <strong>test</strong>',
+			'With a lot of <em>html</em> included': 'Avec beaucoup d\'<em>html</em> inclus'
+		});
+		const result: Buffer = Buffer.from(compiler.compile(collection));
+		expect(result.toString('utf8')).to.equal('msgid ""\nmsgstr ""\n"mime-version: 1.0\\n"\n"Content-Type: text/plain; charset=utf-8\\n"\n"Content-Transfer-Encoding: 8bit\\n"\n\nmsgid "A <strong>test</strong>"\nmsgstr "Un <strong>test</strong>"\n\nmsgid "With a lot of <em>html</em> included"\nmsgstr "Avec beaucoup d\'<em>html</em> inclus"');
+	});
+});
+
+
+

tests/parsers/directive.parser.spec.ts

@@ -3,7 +3,6 @@ import { expect } from 'chai';
 import { DirectiveParser } from '../../src/parsers/directive.parser';
 
 describe('DirectiveParser', () => {
-
 	const templateFilename: string = 'test.template.html';
 	const componentFilename: string = 'test.component.ts';
 
@@ -13,28 +12,89 @@ describe('DirectiveParser', () => {
 		parser = new DirectiveParser();
 	});
 
-	it('should not choke when no html is present in template', () => {
-		const contents = 'Hello World';
+
+	it('should extract keys when using literal map in bound attribute', () => {
+		const contents = `<div [translate]="{ key1: 'value1' | translate, key2: 'value2' | translate }"></div>`;
 		const keys = parser.extract(contents, templateFilename).keys();
-		expect(keys).to.deep.equal([]);
+		expect(keys).to.deep.equal(['value1', 'value2']);
 	});
 
-	it('should use contents as key when there is no translate attribute value provided', () => {
+	it('should extract keys when using literal arrays in bound attribute', () => {
+		const contents = `<div [translate]="[ 'value1' | translate, 'value2' | translate ]"></div>`;
+		const keys = parser.extract(contents, templateFilename).keys();
+		expect(keys).to.deep.equal(['value1', 'value2']);
+	});
+
+	it('should extract keys when using binding pipe in bound attribute', () => {
+		const contents = `<div [translate]="'KEY1' | withPipe"></div>`;
+		const keys = parser.extract(contents, templateFilename).keys();
+		expect(keys).to.deep.equal(['KEY1']);
+	});
+
+	it('should extract keys when using binary expression in bound attribute', () => {
+		const contents = `<div [translate]="keyVar || 'KEY1'"></div>`;
+		const keys = parser.extract(contents, templateFilename).keys();
+		expect(keys).to.deep.equal(['KEY1']);
+	});
+
+	it('should extract keys when using literal primitive in bound attribute', () => {
+		const contents = `<div [translate]="'KEY1'"></div>`;
+		const keys = parser.extract(contents, templateFilename).keys();
+		expect(keys).to.deep.equal(['KEY1']);
+	});
+
+	it('should extract keys when using conditional in bound attribute', () => {
+		const contents = `<div [translate]="condition ? 'KEY1' : 'KEY2'"></div>`;
+		const keys = parser.extract(contents, templateFilename).keys();
+		expect(keys).to.deep.equal(['KEY1', 'KEY2']);
+	});
+
+	it('should extract keys when using nested conditionals in bound attribute', () => {
+		const contents = `<div [translate]="isSunny ? (isWarm ? 'Sunny and warm' : 'Sunny but cold') : 'Not sunny'"></div>`;
+		const keys = parser.extract(contents, templateFilename).keys();
+		expect(keys).to.deep.equal(['Sunny and warm', 'Sunny but cold', 'Not sunny']);
+	});
+
+	it('should extract keys when using interpolation', () => {
+		const contents = `<div translate="{{ 'KEY1' + key2 + 'KEY3' }}"></div>`;
+		const keys = parser.extract(contents, templateFilename).keys();
+		expect(keys).to.deep.equal(['KEY1', 'KEY3']);
+	});
+
+	it('should extract keys keeping proper whitespace', () => {
+		const contents = `
+			<div translate>
+				Wubba
+				Lubba
+				Dub Dub
+			</div>
+		`;
+		const keys = parser.extract(contents, templateFilename).keys();
+		expect(keys).to.deep.equal(['Wubba Lubba Dub Dub']);
+	});
+
+	it('should use element contents as key when no translate attribute value is present', () => {
 		const contents = '<div translate>Hello World</div>';
 		const keys = parser.extract(contents, templateFilename).keys();
 		expect(keys).to.deep.equal(['Hello World']);
 	});
 
-	it('should use translate attribute value as key when provided', () => {
+	it('should use translate attribute value as key when present', () => {
 		const contents = '<div translate="MY_KEY">Hello World<div>';
 		const keys = parser.extract(contents, templateFilename).keys();
 		expect(keys).to.deep.equal(['MY_KEY']);
 	});
 
-	it('should not process children when translate attribute is present', () => {
+	it('should extract keys from child elements when translate attribute is present', () => {
 		const contents = `<div translate>Hello <strong translate>World</strong></div>`;
 		const keys = parser.extract(contents, templateFilename).keys();
-		expect(keys).to.deep.equal(['Hello <strong translate>World</strong>']);
+		expect(keys).to.deep.equal(['Hello', 'World']);
+	});
+
+	it('should not extract keys from child elements when translate attribute is not present', () => {
+		const contents = `<div translate>Hello <strong>World</strong></div>`;
+		const keys = parser.extract(contents, templateFilename).keys();
+		expect(keys).to.deep.equal(['Hello']);
 	});
 
 	it('should extract and parse inline template', () => {
@@ -67,24 +127,47 @@ describe('DirectiveParser', () => {
 		expect(collection.values).to.deep.equal({});
 	});
 
-	it('should extract contents from within custom tags', () => {
+	it('should extract contents from custom elements', () => {
 		const contents = `<custom-table><tbody><tr><td translate>Hello World</td></tr></tbody></custom-table>`;
 		const keys = parser.extract(contents, templateFilename).keys();
 		expect(keys).to.deep.equal(['Hello World']);
 	});
 
-	it('should not cause error when no html is present in template', () => {
+	it('should extract from template without leading/trailing whitespace', () => {
 		const contents = `
-			import { Component } from '@angular/core';
-			@Component({
-				template: '{{ variable }}'
-			})
-			export class MyComponent {
-				variable: string
-			}
+			<div *ngIf="!isLoading && studentsToGrid && studentsToGrid.length == 0" class="no-students" mt-rtl translate>There
+				are currently no students in this class. The good news is, adding students is really easy! Just use the options
+				at the top.
+			</div>
 		`;
-		const keys = parser.extract(contents, componentFilename).keys();
-		expect(keys).to.deep.equal([]);
+		const keys = parser.extract(contents, templateFilename).keys();
+		expect(keys).to.deep.equal([
+			'There are currently no students in this class. The good news is, adding students is really easy! Just use the options at the top.'
+		]);
+	});
+
+	it('should extract keys from element without leading/trailing whitespace', () => {
+		const contents = `
+			<div translate>
+				this is an example
+				of a long label
+			</div>
+
+			<div>
+				<p translate>
+					this is an example
+					of another a long label
+				</p>
+			</div>
+		`;
+		const keys = parser.extract(contents, templateFilename).keys();
+		expect(keys).to.deep.equal(['this is an example of a long label', 'this is an example of another a long label']);
+	});
+
+	it('should collapse excessive whitespace', () => {
+		const contents = '<p translate>this      is an example</p>';
+		const keys = parser.extract(contents, templateFilename).keys();
+		expect(keys).to.deep.equal(['this is an example']);
 	});
 
 });

tests/parsers/function.parser.spec.ts

@@ -1,30 +0,0 @@
-import { expect } from 'chai';
-
-import { FunctionParser } from '../../src/parsers/function.parser';
-
-describe('FunctionParser', () => {
-
-	const componentFilename: string = 'test.component.ts';
-
-	let parser: FunctionParser;
-
-	beforeEach(() => {
-		parser = new FunctionParser();
-	});
-
-
-	it('should extract strings using marker function', () => {
-		const contents = `
-			import { marker } from '@biesbjerg/ngx-translate-extract-marker';
-			marker('Hello world');
-			marker(['I', 'am', 'extracted']);
-			otherFunction('But I am not');
-			marker(message || 'binary expression');
-			marker(message ? message : 'conditional operator');
-			marker('FOO.bar');
-		`;
-		const keys = parser.extract(contents, componentFilename).keys();
-		expect(keys).to.deep.equal(['Hello world', 'I', 'am', 'extracted', 'binary expression', 'conditional operator', 'FOO.bar']);
-	});
-
-});

tests/parsers/marker.parser.spec.ts

@@ -0,0 +1,64 @@
+import { expect } from 'chai';
+
+import { MarkerParser } from '../../src/parsers/marker.parser';
+
+describe('MarkerParser', () => {
+	const componentFilename: string = 'test.component.ts';
+
+	let parser: MarkerParser;
+
+	beforeEach(() => {
+		parser = new MarkerParser();
+	});
+
+	it('should extract strings using marker function', () => {
+		const contents = `
+			import { marker } from '@biesbjerg/ngx-translate-extract-marker';
+			marker('Hello world');
+			marker(['I', 'am', 'extracted']);
+			otherFunction('But I am not');
+			marker(message || 'binary expression');
+			marker(message ? message : 'conditional operator');
+			marker('FOO.bar');
+		`;
+		const keys = parser.extract(contents, componentFilename).keys();
+		expect(keys).to.deep.equal(['Hello world', 'I', 'am', 'extracted', 'binary expression', 'conditional operator', 'FOO.bar']);
+	});
+
+	it('should extract split strings', () => {
+		const contents = `
+			import { marker as _ } from '@biesbjerg/ngx-translate-extract-marker';
+			_('Hello ' + 'world');
+			_('This is a ' + 'very ' + 'very ' + 'very ' + 'very ' + 'long line.');
+			_('Mix ' + \`of \` + 'different ' + \`types\`);
+		`;
+		const keys = parser.extract(contents, componentFilename).keys();
+		expect(keys).to.deep.equal(['Hello world', 'This is a very very very very long line.', 'Mix of different types']);
+	});
+
+	it('should extract split strings while keeping html tags', () => {
+		const contents = `
+			import { marker as _ } from '@biesbjerg/ngx-translate-extract-marker';
+			_('Hello ' + 'world');
+			_('This <em>is</em> a ' + 'very ' + 'very ' + 'very ' + 'very ' + 'long line.');
+			_('Mix ' + \`of \` + 'different ' + \`types\`);
+		`;
+		const keys = parser.extract(contents, componentFilename).keys();
+		expect(keys).to.deep.equal(['Hello world', 'This <em>is</em> a very very very very long line.', 'Mix of different types']);
+	});
+
+	it('should extract the strings', () => {
+		const contents = `
+		import { marker } from '@biesbjerg/ngx-translate-extract-marker';
+
+		export class AppModule {
+			constructor() {
+				marker('DYNAMIC_TRAD.val1');
+				marker('DYNAMIC_TRAD.val2');
+			}
+		}
+		`;
+		const keys = parser.extract(contents, componentFilename).keys();
+		expect(keys).to.deep.equal(['DYNAMIC_TRAD.val1', 'DYNAMIC_TRAD.val2']);
+	});
+});

tests/parsers/pipe.parser.spec.ts

@@ -3,7 +3,6 @@ import { expect } from 'chai';
 import { PipeParser } from '../../src/parsers/pipe.parser';
 
 describe('PipeParser', () => {
-
 	const templateFilename: string = 'test.template.html';
 
 	let parser: PipeParser;
@@ -30,12 +29,78 @@ describe('PipeParser', () => {
 		expect(keys).to.deep.equal(['World']);
 	});
 
-	it('should extract interpolated strings when translate pipe is used in conjunction with other pipes', () => {
+	it('should extract interpolated strings when translate pipe is used before other pipes', () => {
 		const contents = `Hello {{ 'World' | translate | upper }}`;
 		const keys = parser.extract(contents, templateFilename).keys();
 		expect(keys).to.deep.equal(['World']);
 	});
 
+	it('should extract interpolated strings when translate pipe is used after other pipes', () => {
+		const contents = `Hello {{ 'World'  | upper | translate }}`;
+		const keys = parser.extract(contents, templateFilename).keys();
+		expect(keys).to.deep.equal(['World']);
+	});
+
+	it('should extract strings from ternary operators inside interpolations', () => {
+		const contents = `{{ (condition ? 'Hello' : 'World') | translate }}`;
+		const keys = parser.extract(contents, templateFilename).keys();
+		expect(keys).to.deep.equal(['Hello', 'World']);
+	});
+
+	it('should extract strings from ternary operators right expression', () => {
+		const contents = `{{ condition ? null : ('World' | translate) }}`;
+		const keys = parser.extract(contents, templateFilename).keys();
+		expect(keys).to.deep.equal(['World']);
+	});
+
+	it('should extract strings from ternary operators inside attribute bindings', () => {
+		const contents = `<span [attr]="condition ? null : ('World' | translate)"></span>`;
+		const keys = parser.extract(contents, templateFilename).keys();
+		expect(keys).to.deep.equal(['World']);
+	});
+
+	it('should extract strings from ternary operators left expression', () => {
+		const contents = `{{ condition ? ('World' | translate) : null }}`;
+		const keys = parser.extract(contents, templateFilename).keys();
+		expect(keys).to.deep.equal(['World']);
+	});
+
+	it('should extract strings inside string concatenation', () => {
+		const contents = `{{ 'a' + ('Hello' | translate) + 'b' + 'c' + ('World' | translate) + 'd' }}`;
+		const keys = parser.extract(contents, templateFilename).keys();
+		expect(keys).to.deep.equal(['Hello', 'World']);
+	});
+
+	it('should extract strings from object', () => {
+		const contents = `{{ { foo: 'Hello' | translate, bar: ['World' | translate], deep: { nested: { baz: 'Yes' | translate } } } | json }}`;
+		const keys = parser.extract(contents, templateFilename).keys();
+		expect(keys).to.deep.equal(['Hello', 'World', 'Yes']);
+	});
+
+	it('should extract strings from ternary operators inside attribute bindings', () => {
+		const contents = `<span [attr]="(condition ? 'Hello' : 'World') | translate"></span>`;
+		const keys = parser.extract(contents, templateFilename).keys();
+		expect(keys).to.deep.equal(['Hello', 'World']);
+	});
+
+	it('should extract strings from nested expressions', () => {
+		const contents = `<span [attr]="{ foo: ['a' + ((condition ? 'Hello' : 'World') | translate) + 'b'] }"></span>`;
+		const keys = parser.extract(contents, templateFilename).keys();
+		expect(keys).to.deep.equal(['Hello', 'World']);
+	});
+
+	it('should extract strings from nested ternary operators ', () => {
+		const contents = `<h3>{{ (condition ? 'Hello' : anotherCondition ? 'Nested' : 'World' ) | translate }}</h3>`;
+		const keys = parser.extract(contents, templateFilename).keys();
+		expect(keys).to.deep.equal(['Hello', 'Nested', 'World']);
+	});
+
+	it('should extract strings from ternary operators inside attribute interpolations', () => {
+		const contents = `<span attr="{{(condition ? 'Hello' : 'World') | translate}}"></span>`;
+		const keys = parser.extract(contents, templateFilename).keys();
+		expect(keys).to.deep.equal(['Hello', 'World']);
+	});
+
 	it('should extract strings with escaped quotes', () => {
 		const contents = `Hello {{ 'World\\'s largest potato' | translate }}`;
 		const keys = parser.extract(contents, templateFilename).keys();
@@ -60,7 +125,7 @@ describe('PipeParser', () => {
 		expect(keys).to.deep.equal(['Hello World']);
 	});
 
-	it('should not use a greedy regular expression', () => {
+	it('should extract multiple entries from nodes', () => {
 		const contents = `
 			<ion-header>
 				<ion-navbar color="brand">
@@ -119,4 +184,21 @@ describe('PipeParser', () => {
 		expect(keys).to.deep.equal(['message']);
 	});
 
+	it('should ignore calculated values', () => {
+		const contents = `{{ 'SOURCES.' + source.name + '.NAME_PLURAL' | translate }}`;
+		const keys = parser.extract(contents, templateFilename).keys();
+		expect(keys).to.deep.equal([]);
+	});
+
+	it('should not extract pipe argument', () => {
+		const contents = `{{ value | valueToTranslationKey: 'argument' | translate }}`;
+		const keys = parser.extract(contents, templateFilename).keys();
+		expect(keys).to.deep.equal([]);
+	});
+
+	it('should extract strings from piped arguments inside a function calls on templates', () => {
+		const contents = `{{ callMe('Hello' | translate, 'World' | translate ) }}`;
+		const keys = parser.extract(contents, templateFilename).keys();
+		expect(keys).to.deep.equal([`Hello`, `World`]);
+	});
 });

tests/parsers/service.parser.spec.ts

@@ -2,18 +2,25 @@ import { expect } from 'chai';
 
 import { ServiceParser } from '../../src/parsers/service.parser';
 
-class TestServiceParser extends ServiceParser {
-
-}
-
 describe('ServiceParser', () => {
-
 	const componentFilename: string = 'test.component.ts';
 
-	let parser: TestServiceParser;
+	let parser: ServiceParser;
 
 	beforeEach(() => {
-		parser = new TestServiceParser();
+		parser = new ServiceParser();
+	});
+
+	it('should extract strings when TranslateService is accessed directly via constructor parameter', () => {
+		const contents = `
+			@Component({ })
+			export class MyComponent {
+				public constructor(protected translateService: TranslateService) {
+					translateService.get('It works!');
+				}
+		`;
+		const keys = parser.extract(contents, componentFilename).keys();
+		expect(keys).to.deep.equal(['It works!']);
 	});
 
 	it('should support extracting binary expressions', () => {
@@ -44,7 +51,7 @@ describe('ServiceParser', () => {
 		expect(keys).to.deep.equal(['Fallback message']);
 	});
 
-	it('should extract strings in TranslateService\'s get() method', () => {
+	it("should extract strings in TranslateService's get() method", () => {
 		const contents = `
 			@Component({ })
 			export class AppComponent {
@@ -57,7 +64,7 @@ describe('ServiceParser', () => {
 		expect(keys).to.deep.equal(['Hello World']);
 	});
 
-	it('should extract strings in TranslateService\'s instant() method', () => {
+	it("should extract strings in TranslateService's instant() method", () => {
 		const contents = `
 			@Component({ })
 			export class AppComponent {
@@ -70,7 +77,7 @@ describe('ServiceParser', () => {
 		expect(keys).to.deep.equal(['Hello World']);
 	});
 
-	it('should extract strings in TranslateService\'s stream() method', () => {
+	it("should extract strings in TranslateService's stream() method", () => {
 		const contents = `
 			@Component({ })
 			export class AppComponent {
@@ -83,7 +90,7 @@ describe('ServiceParser', () => {
 		expect(keys).to.deep.equal(['Hello World']);
 	});
 
-	it('should extract array of strings in TranslateService\'s get() method', () => {
+	it("should extract array of strings in TranslateService's get() method", () => {
 		const contents = `
 			@Component({ })
 			export class AppComponent {
@@ -96,7 +103,7 @@ describe('ServiceParser', () => {
 		expect(keys).to.deep.equal(['Hello', 'World']);
 	});
 
-	it('should extract array of strings in TranslateService\'s instant() method', () => {
+	it("should extract array of strings in TranslateService's instant() method", () => {
 		const contents = `
 			@Component({ })
 			export class AppComponent {
@@ -109,7 +116,7 @@ describe('ServiceParser', () => {
 		expect(key).to.deep.equal(['Hello', 'World']);
 	});
 
-	it('should extract array of strings in TranslateService\'s stream() method', () => {
+	it("should extract array of strings in TranslateService's stream() method", () => {
 		const contents = `
 			@Component({ })
 			export class AppComponent {
@@ -224,6 +231,7 @@ describe('ServiceParser', () => {
 						console.log(translations[variable]);
 					});
 				}
+			}
 		`;
 		const keys = parser.extract(contents, componentFilename).keys();
 		expect(keys).to.deep.equal(['yes']);
@@ -263,4 +271,38 @@ describe('ServiceParser', () => {
 		expect(keys).to.deep.equal(['Extract me!', 'Hello!']);
 	});
 
+	it('should extract strings when TranslateService is declared as a property', () => {
+		const contents = `
+			export class MyComponent {
+				protected translateService: TranslateService;
+				public constructor() {
+					this.translateService = new TranslateService();
+				}
+				public test() {
+					this.translateService.instant('Hello World');
+				}
+		`;
+		const keys = parser.extract(contents, componentFilename).keys();
+		expect(keys).to.deep.equal(['Hello World']);
+	});
+
+	it('should extract strings passed to TranslateServices methods only', () => {
+		const contents = `
+			export class AppComponent implements OnInit {
+				constructor(protected config: Config, protected translateService: TranslateService) {}
+
+				public ngOnInit(): void {
+					this.localizeBackButton();
+				}
+
+				protected localizeBackButton(): void {
+					this.translateService.onLangChange.subscribe((event: LangChangeEvent) => {
+						this.config.set('backButtonText', this.translateService.instant('Back'));
+					});
+				}
+			}
+		`;
+		const keys = parser.extract(contents, componentFilename).keys();
+		expect(keys).to.deep.equal(['Back']);
+	});
 });

tests/parsers/utils.spec.ts

@@ -3,7 +3,6 @@ import { expect } from 'chai';
 import { isPathAngularComponent, extractComponentInlineTemplate } from '../../src/utils/utils';
 
 describe('Utils', () => {
-
 	it('should recognize js extension as angular component', () => {
 		const result = isPathAngularComponent('test.js');
 		expect(result).to.equal(true);
@@ -63,5 +62,4 @@ describe('Utils', () => {
 		const template = extractComponentInlineTemplate(contents);
 		expect(template).to.equal('\n\t\t\t\t\t<p>\n\t\t\t\t\t\tHello World\n\t\t\t\t\t</p>\n\t\t\t\t');
 	});
-
 });

tests/post-processors/key-as-default-value.post-processor.spec.ts

@@ -5,7 +5,6 @@ import { KeyAsDefaultValuePostProcessor } from '../../src/post-processors/key-as
 import { TranslationCollection } from '../../src/utils/translation.collection';
 
 describe('KeyAsDefaultValuePostProcessor', () => {
-
 	let processor: PostProcessorInterface;
 
 	beforeEach(() => {
@@ -27,5 +26,4 @@ describe('KeyAsDefaultValuePostProcessor', () => {
 			'Use this key as value as well': 'Use this key as value as well'
 		});
 	});
-
 });

tests/post-processors/null-as-default-value.post-processor.spec.ts

@@ -0,0 +1,40 @@
+import { expect } from 'chai';
+
+import { PostProcessorInterface } from '../../src/post-processors/post-processor.interface';
+import { NullAsDefaultValuePostProcessor } from '../../src/post-processors/null-as-default-value.post-processor';
+import { TranslationCollection } from '../../src/utils/translation.collection';
+
+describe('NullAsDefaultValuePostProcessor', () => {
+	let processor: PostProcessorInterface;
+
+	beforeEach(() => {
+		processor = new NullAsDefaultValuePostProcessor();
+	});
+
+	it('should use null as default value', () => {
+		const draft = new TranslationCollection({ 'String A': '' });
+		const extracted = new TranslationCollection({ 'String A': '' });
+		const existing = new TranslationCollection();
+		expect(processor.process(draft, extracted, existing).values).to.deep.equal({
+			'String A': null
+		});
+	});
+
+	it('should keep existing value even if it is an empty string', () => {
+		const draft = new TranslationCollection({ 'String A': '' });
+		const extracted = new TranslationCollection({ 'String A': '' });
+		const existing = new TranslationCollection({ 'String A': '' });
+		expect(processor.process(draft, extracted, existing).values).to.deep.equal({
+			'String A': ''
+		});
+	});
+
+	it('should keep existing value', () => {
+		const draft = new TranslationCollection({ 'String A': 'Streng A' });
+		const extracted = new TranslationCollection({ 'String A': 'Streng A' });
+		const existing = new TranslationCollection({ 'String A': 'Streng A' });
+		expect(processor.process(draft, extracted, existing).values).to.deep.equal({
+			'String A': 'Streng A'
+		});
+	});
+});

tests/post-processors/purge-obsolete-keys.post-processor.spec.ts

@@ -5,15 +5,14 @@ import { PurgeObsoleteKeysPostProcessor } from '../../src/post-processors/purge-
 import { TranslationCollection } from '../../src/utils/translation.collection';
 
 describe('PurgeObsoleteKeysPostProcessor', () => {
-
-	let processor: PostProcessorInterface;
+	let postProcessor: PostProcessorInterface;
 
 	beforeEach(() => {
-		processor = new PurgeObsoleteKeysPostProcessor();
+		postProcessor = new PurgeObsoleteKeysPostProcessor();
 	});
 
 	it('should purge obsolete keys', () => {
-		const collection = new TranslationCollection({
+		const draft = new TranslationCollection({
 			'I am completely new': '',
 			'I already exist': '',
 			'I already exist but was not present in extract': ''
@@ -27,10 +26,9 @@ describe('PurgeObsoleteKeysPostProcessor', () => {
 			'I already exist but was not present in extract': ''
 		});
 
-		expect(processor.process(collection, extracted, existing).values).to.deep.equal({
+		expect(postProcessor.process(draft, extracted, existing).values).to.deep.equal({
 			'I am completely new': '',
 			'I already exist': ''
 		});
 	});
-
 });

tests/post-processors/sort-by-key.post-processor.spec.ts

@@ -5,7 +5,6 @@ import { SortByKeyPostProcessor } from '../../src/post-processors/sort-by-key.po
 import { TranslationCollection } from '../../src/utils/translation.collection';
 
 describe('SortByKeyPostProcessor', () => {
-
 	let processor: PostProcessorInterface;
 
 	beforeEach(() => {
@@ -14,20 +13,19 @@ describe('SortByKeyPostProcessor', () => {
 
 	it('should sort keys alphanumerically', () => {
 		const collection = new TranslationCollection({
-			'z': 'last value',
-			'a': 'a value',
+			z: 'last value',
+			a: 'a value',
 			'9': 'a numeric key',
-			'b': 'another value'
+			b: 'another value'
 		});
 		const extracted = new TranslationCollection();
 		const existing = new TranslationCollection();
 
 		expect(processor.process(collection, extracted, existing).values).to.deep.equal({
 			'9': 'a numeric key',
-			'a': 'a value',
-			'b': 'another value',
-			'z': 'last value'
+			a: 'a value',
+			b: 'another value',
+			z: 'last value'
 		});
 	});
-
 });

tests/post-processors/string-as-default-value.post-processor.spec.ts

@@ -0,0 +1,40 @@
+import { expect } from 'chai';
+
+import { PostProcessorInterface } from '../../src/post-processors/post-processor.interface';
+import { StringAsDefaultValuePostProcessor } from '../../src/post-processors/string-as-default-value.post-processor';
+import { TranslationCollection } from '../../src/utils/translation.collection';
+
+describe('StringAsDefaultValuePostProcessor', () => {
+	let processor: PostProcessorInterface;
+
+	beforeEach(() => {
+		processor = new StringAsDefaultValuePostProcessor({ defaultValue: 'default' });
+	});
+
+	it('should use string as default value', () => {
+		const draft = new TranslationCollection({ 'String A': '' });
+		const extracted = new TranslationCollection({ 'String A': '' });
+		const existing = new TranslationCollection();
+		expect(processor.process(draft, extracted, existing).values).to.deep.equal({
+			'String A': 'default'
+		});
+	});
+
+	it('should keep existing value even if it is an empty string', () => {
+		const draft = new TranslationCollection({ 'String A': '' });
+		const extracted = new TranslationCollection({ 'String A': '' });
+		const existing = new TranslationCollection({ 'String A': '' });
+		expect(processor.process(draft, extracted, existing).values).to.deep.equal({
+			'String A': ''
+		});
+	});
+
+	it('should keep existing value', () => {
+		const draft = new TranslationCollection({ 'String A': 'Streng A' });
+		const extracted = new TranslationCollection({ 'String A': 'Streng A' });
+		const existing = new TranslationCollection({ 'String A': 'Streng A' });
+		expect(processor.process(draft, extracted, existing).values).to.deep.equal({
+			'String A': 'Streng A'
+		});
+	});
+});

tests/utils/translation.collection.spec.ts

@@ -3,7 +3,6 @@ import { expect } from 'chai';
 import { TranslationCollection } from '../../src/utils/translation.collection';
 
 describe('StringCollection', () => {
-
 	let collection: TranslationCollection;
 
 	beforeEach(() => {
@@ -64,7 +63,10 @@ describe('StringCollection', () => {
 	it('should merge with other collection', () => {
 		collection = collection.add('oldKey', 'oldVal');
 		const newCollection = new TranslationCollection({ newKey: 'newVal' });
-		expect(collection.union(newCollection).values).to.deep.equal({ oldKey: 'oldVal', newKey: 'newVal' });
+		expect(collection.union(newCollection).values).to.deep.equal({
+			oldKey: 'oldVal',
+			newKey: 'newVal'
+		});
 	});
 
 	it('should intersect with passed collection', () => {
@@ -88,7 +90,10 @@ describe('StringCollection', () => {
 	it('should map values', () => {
 		collection = new TranslationCollection({ red: 'rød', green: 'grøn', blue: 'blå' });
 		collection = collection.map((key, val) => 'mapped value');
-		expect(collection.values).to.deep.equal({ red: 'mapped value', green: 'mapped value', blue: 'mapped value' });
+		expect(collection.values).to.deep.equal({
+			red: 'mapped value',
+			green: 'mapped value',
+			blue: 'mapped value'
+		});
 	});
-
 });

tsconfig.json

@@ -1,23 +1,25 @@
 {
     "compilerOptions": {
         "allowSyntheticDefaultImports": true,
-        "noUnusedLocals": true,
         "noImplicitAny": true,
+        "noImplicitReturns": true,
+        "noImplicitThis": true,
+        "noImplicitUseStrict": true,
         "removeComments": true,
         "declaration": true,
-        "target": "es2015",
+        "target": "es2019",
         "lib": [
-            "dom",
-            "es2018"
+            "es2019"
         ],
         "module": "commonjs",
-        "outDir": "./dist/",
-        "sourceMap": true
+        "outDir": "dist",
+        "sourceMap": true,
+        "typeRoots" : [
+            "node_modules/@types"
+        ]
     },
     "include": [
         "src/**/*.ts"
     ],
-    "exclude": [
-        "node_modules"
-    ]
+    "exclude": []
 }

tslint.commit.json

@@ -0,0 +1,8 @@
+{
+  "extends": ["./tslint.json", "tslint-etc"],
+  "jsRules": {},
+  "rules": {
+    "ordered-imports": false,
+    "no-unused-declaration": true
+  }
+}

tslint.json

@@ -1,53 +1,118 @@
 {
-	"rulesDirectory": [
-		"node_modules/tslint-eslint-rules/dist/rules"
+  "defaultSeverity": "error",
+  "extends": [
+    "tslint-config-prettier"
   ],
   "rules": {
-		"indent": [true, "tabs"],
-		"semicolon": [true, "always", "ignore-interfaces"],
-		"quotemark": [true, "single", "avoid-escape"],
-		"only-arrow-functions": false,
-		"no-duplicate-variable": true,
-		"member-access": true,
+    "arrow-return-shorthand": true,
+    "callable-types": true,
+    "class-name": true,
+    "comment-format": [
+      true,
+      "check-space"
+    ],
+    "curly": true,
+    "deprecation": {
+      "severity": "warn"
+    },
+    "eofline": true,
+    "forin": true,
+    "import-spacing": true,
+    "indent": [
+      true,
+      "tabs"
+    ],
+    "interface-over-type-literal": true,
+    "label-position": true,
+    "max-line-length": [
+      true,
+      220
+    ],
+    "member-access": false,
     "member-ordering": [
       true,
       {
         "order": [
-					"public-static-field",
-					"public-static-method",
-					"protected-static-field",
-					"protected-static-method",
-					"private-static-field",
-					"private-static-method",
-					"public-instance-field",
-					"protected-instance-field",
-					"private-instance-field",
-					"constructor",
-					"public-instance-method",
-					"protected-instance-method",
-					"private-instance-method"
+          "static-field",
+          "instance-field",
+          "static-method",
+          "instance-method"
         ]
       }
     ],
-		"curly": true,
-		"eofline": true,
+    "no-arg": true,
+    "no-bitwise": true,
+    "no-console": [
+      true,
+      "debug",
+      "info",
+      "time",
+      "timeEnd",
+      "trace"
+    ],
+    "no-construct": true,
+    "no-debugger": true,
+    "no-duplicate-super": true,
+    "no-empty": false,
+    "no-empty-interface": true,
+    "no-eval": true,
+    "no-inferrable-types": [
+      false,
+      "ignore-params"
+    ],
+    "no-misused-new": true,
+    "no-non-null-assertion": true,
+    "no-shadowed-variable": true,
+    "no-string-literal": false,
+    "no-string-throw": true,
+    "no-switch-case-fall-through": true,
     "no-trailing-whitespace": true,
-		"trailing-comma": [
+    "no-unnecessary-initializer": true,
+    "no-unused-expression": true,
+    "no-var-keyword": true,
+    "object-literal-sort-keys": false,
+    "one-line": [
+      true,
+      "check-open-brace",
+      "check-catch",
+      "check-else",
+      "check-whitespace"
+    ],
+    "prefer-const": true,
+    "radix": true,
+    "semicolon": [
+      true,
+      "always"
+    ],
+    "triple-equals": [
+      true,
+      "allow-null-check"
+    ],
+    "typedef-whitespace": [
       true,
       {
-				"multiline": "never",
-				"singleline": "never"
+        "call-signature": "nospace",
+        "index-signature": "nospace",
+        "parameter": "nospace",
+        "property-declaration": "nospace",
+        "variable-declaration": "nospace"
       }
     ],
+    "unified-signatures": true,
+    "variable-name": [
+      true,
+      "ban-keywords",
+      "allow-pascal-case",
+      "check-format"
+    ],
     "whitespace": [
       true,
       "check-branch",
       "check-decl",
       "check-operator",
-			"check-module",
       "check-separator",
-			"check-type",
-			"check-typecast"
-		]
+      "check-type"
+    ],
+    "quotemark": [true, "single"]
   }
 }