update README

README.md

@@ -78,7 +78,7 @@ _('Extract me');
 `ngx-translate-extract ... -m _`
 
 ## Commandline arguments
-```shell
+```
 Usage:
 ngx-translate-extract [options]
 
@@ -89,19 +89,22 @@ Options:
                               can use path expansion, glob patterns and multiple
                               paths
                       [array] [default: current working path]
-  --patterns, -p              Extract strings from the following file patterns
+     [array] [required] [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]
-  --format, -f                Output format
+  --output, -o                 Paths where you would like to save extracted
+                               strings. You can use path expansion, glob
+                               patterns and multiple paths    [array] [required]
+  --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]
+  --format-indentation, --fi   Output format indentation  [string] [default: "	"]
+  --replace, -r                Replace the contents of output file if it exists
+                               (Merges by default)                     [boolean]
+  --sort, -s                   Sort strings in alphabetical order when saving
+                                                                       [boolean]
+  --clean, -c                  Remove obsolete strings when merging    [boolean]
+  --key-as-default-value, -k   Use key as default value for translations
+                                                                       [boolean]
+  --null-as-default-value, -n  Use null as default value for translations
+                                                                       [boolean]
+```

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@biesbjerg/ngx-translate-extract",
-  "version": "4.0.0",
+  "version": "4.2.0",
   "description": "Extract strings from projects using ngx-translate",
   "main": "dist/index.js",
   "typings": "dist/index.d.ts",

src/cli/cli.ts

@@ -10,6 +10,7 @@ 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 { PurgeObsoleteKeysPostProcessor } from '../post-processors/purge-obsolete-keys.post-processor';
 import { CompilerInterface } from '../compilers/compiler.interface';
 import { CompilerFactory } from '../compilers/compiler.factory';
@@ -24,12 +25,13 @@ 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 as unknown as string[]).forEach((dir: string) => {
+		options.input.forEach((dir: string) => {
 			if (!fs.existsSync(dir) || !fs.statSync(dir).isDirectory()) {
 				throw new Error(`The path you supplied was not found: '${dir}'`);
 			}
@@ -66,31 +68,33 @@ export const cli = yargs
 	.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,
 		type: 'boolean'
 	})
 	.option('clean', {
 		alias: 'c',
 		describe: 'Remove obsolete strings when merging',
-		default: false,
 		type: 'boolean'
 	})
 	.option('key-as-default-value', {
 		alias: 'k',
 		describe: 'Use key as default value for translations',
-		default: false,
 		type: 'boolean'
 	})
+	.option('null-as-default-value', {
+		alias: 'n',
+		describe: 'Use null as default value for translations',
+		type: 'boolean'
+	})
+	.conflicts('key-as-default-value', 'null-as-default-value')
 	.exitProcess(true)
 	.parse(process.argv);
 
-const extractTask = new ExtractTask(cli.input as unknown as string[], cli.output, {
+const extractTask = new ExtractTask(cli.input, cli.output, {
 	replace: cli.replace,
 	patterns: cli.patterns
 });
@@ -111,6 +115,8 @@ if (cli.clean) {
 }
 if (cli.keyAsDefaultValue) {
 	postProcessors.push(new KeyAsDefaultValuePostProcessor());
+} else if (cli.nullAsDefaultValue) {
+	postProcessors.push(new NullAsDefaultValuePostProcessor());
 }
 if (cli.sort) {
 	postProcessors.push(new SortByKeyPostProcessor());

src/parsers/marker.parser.ts

@@ -9,7 +9,7 @@ const MARKER_PACKAGE_IMPORT_NAME = 'marker';
 
 export class MarkerParser implements ParserInterface {
 
-	public extract(contents: string, filePath: string): TranslationCollection {
+	public extract(contents: string, filePath: string): TranslationCollection | null {
 		const sourceFile = tsquery.ast(contents, filePath);
 
 		const markerFnName = getNamedImportAlias(sourceFile, MARKER_PACKAGE_MODULE_NAME, MARKER_PACKAGE_IMPORT_NAME);

src/parsers/parser.interface.ts

@@ -2,6 +2,6 @@ import { TranslationCollection } from '../utils/translation.collection';
 
 export interface ParserInterface {
 
-	extract(template: string, path: string): TranslationCollection;
+	extract(source: string, filePath: string): TranslationCollection | null;
 
 }

src/parsers/service.parser.ts

@@ -2,14 +2,14 @@ import { tsquery } from '@phenomnomnominal/tsquery';
 
 import { ParserInterface } from './parser.interface';
 import { TranslationCollection } from '../utils/translation.collection';
-import { findClasses, findClassPropertyByType, findMethodCallExpression, getStringsFromExpression } from '../utils/ast-helpers';
+import { findClasses, findClassPropertyByType, findMethodCallExpressions, getStringsFromExpression } from '../utils/ast-helpers';
 
 const TRANSLATE_SERVICE_TYPE_REFERENCE = 'TranslateService';
 const TRANSLATE_SERVICE_METHOD_NAMES = ['get', 'instant', 'stream'];
 
 export class ServiceParser implements ParserInterface {
 
-	public extract(source: string, filePath: string): TranslationCollection {
+	public extract(source: string, filePath: string): TranslationCollection | null {
 		const sourceFile = tsquery.ast(source, filePath);
 
 		const classNodes = findClasses(sourceFile);
@@ -25,7 +25,7 @@ export class ServiceParser implements ParserInterface {
 				return;
 			}
 
-			const callNodes = findMethodCallExpression(classNode, propName, TRANSLATE_SERVICE_METHOD_NAMES);
+			const callNodes = findMethodCallExpressions(classNode, propName, TRANSLATE_SERVICE_METHOD_NAMES);
 			callNodes.forEach(callNode => {
 				const [firstArgNode] = callNode.arguments;
 				if (!firstArgNode) {

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

@@ -0,0 +1,12 @@
+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/utils/ast-helpers.ts

@@ -72,7 +72,7 @@ export function findFunctionCallExpressions(node: Node, fnName: string | string[
 	return nodes;
 }
 
-export function findMethodCallExpression(node: Node, prop: string, fnName: string | string[]): CallExpression[] {
+export function findMethodCallExpressions(node: Node, prop: string, fnName: string | string[]): CallExpression[] {
 	if (Array.isArray(fnName)) {
 		fnName = fnName.join('|');
 	}

tests/parsers/marker.parser.spec.ts

@@ -27,4 +27,19 @@ describe('MarkerParser', () => {
 		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'
+		]);
+	});
+
 });

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

@@ -0,0 +1,42 @@
+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'
+		});
+	});
+
+});

tsconfig.json

@@ -12,7 +12,10 @@
         ],
         "module": "commonjs",
         "outDir": "./dist/",
-        "sourceMap": true
+        "sourceMap": true,
+        "typeRoots" : [
+            "./node_modules/@types"
+        ],
     },
     "include": [
         "src/**/*.ts"