*: fix warnings from go vet

system/fleet_test.go

@@ -48,7 +48,7 @@ Environment="FLEET_PUBLIC_IP=12.34.56.78"
 	} {
 		units := Fleet{tt.config}.Units()
 		if !reflect.DeepEqual(units, tt.units) {
-			t.Errorf("bad units (%q): want %q, got %q", tt.config, tt.units, units)
+			t.Errorf("bad units (%q): want %#v, got %#v", tt.config, tt.units, units)
 		}
 	}
 }

system/oem_test.go

@@ -54,7 +54,7 @@ BUG_REPORT_URL="https://github.com/coreos/coreos-overlay"
 	} {
 		file, err := OEM{tt.config}.File()
 		if err != nil {
-			t.Errorf("bad error (%q): want %q, got %q", tt.config, nil, err)
+			t.Errorf("bad error (%q): want %v, got %q", tt.config, nil, err)
 		}
 		if !reflect.DeepEqual(tt.file, file) {
 			t.Errorf("bad file (%q): want %#v, got %#v", tt.config, tt.file, file)

system/systemd_test.go

@@ -187,10 +187,10 @@ func TestMaskUnit(t *testing.T) {
 	fooPath := path.Join(dir, "etc", "systemd", "system", "foo.service")
 	fooTgt, err := os.Readlink(fooPath)
 	if err != nil {
-		t.Fatalf("Unable to read link", err)
+		t.Fatal("Unable to read link", err)
 	}
 	if fooTgt != "/dev/null" {
-		t.Fatalf("unit not masked, got unit target", fooTgt)
+		t.Fatal("unit not masked, got unit target", fooTgt)
 	}
 
 	// Ensure mask works with unit files that already exist
@@ -204,10 +204,10 @@ func TestMaskUnit(t *testing.T) {
 	}
 	barTgt, err := os.Readlink(barPath)
 	if err != nil {
-		t.Fatalf("Unable to read link", err)
+		t.Fatal("Unable to read link", err)
 	}
 	if barTgt != "/dev/null" {
-		t.Fatalf("unit not masked, got unit target", barTgt)
+		t.Fatal("unit not masked, got unit target", barTgt)
 	}
 }
 
@@ -254,7 +254,7 @@ func TestUnmaskUnit(t *testing.T) {
 		t.Errorf("unmask of unit returned unexpected error: %v", err)
 	}
 	if _, err := os.Stat(dst); !os.IsNotExist(err) {
-		t.Errorf("expected %s to not exist after unmask, but got err: %s", err)
+		t.Errorf("expected %s to not exist after unmask, but got err: %s", dst, err)
 	}
 }