feat: add no-empty-messages rule

README.md

@@ -46,7 +46,8 @@ For each project where you want to run the i18n-validator, you will need to have
 	 *
 	 **/
 	"rules": {
-		"no-untranslated-files": "error"
+		"no-untranslated-messages": "error",
+		"no-empty-messages": "error"
 	},
 	/**
 	 * Set this dryRun setting to true to get all the same logging and reporting you would

i18n-validator.config.json

@@ -7,7 +7,8 @@
 	},
 	"pathToTranslatedFiles": "src/tests/fixtures/i18n",
 	"rules": {
-		"no-untranslated-messages": "error"
+		"no-untranslated-messages": "error",
+		"no-empty-messages": "error"
 	},
 	"dryRun": false,
 	"enabled": true

src/config/default-config.ts

@@ -6,7 +6,8 @@ const config: Config = {
 	translationFiles: {},
 	pathToTranslatedFiles: "i18n",
 	rules: {
-		"no-untranslated-files": "error",
+		"no-untranslated-messages": "error",
+		"no-empty-messages": "error",
 	},
 	dryRun: false,
 	enabled: true,

src/rules/index.ts

@@ -1,3 +1,4 @@
+import { noEmptyMessages } from "./no-empty-messages/no-empty-messages.js";
 import { noUntranslatedMessages } from "./no-untranslated-messages/index.js";
 
-export { noUntranslatedMessages };
+export { noUntranslatedMessages, noEmptyMessages };

src/rules/no-empty-messages/README.md

@@ -0,0 +1,48 @@
+# no-empty-messages
+
+The no-empty-messages rule ensures that all messages in the translation files are not empty strings. It also verifies that messages in the base locale are not empty.
+
+The rule runs through all the messages in the translation files and checks for:
+
+1. Empty messages in the base locale file.
+2. Empty messages in the translation files that correspond to a non-empty message in the base locale file.
+
+Assuming `en.json` is where your default language is (the source file):
+
+❌ Example of **incorrect** setup for this rule (all messages are empty):
+
+```js
+en.json: { 'hello': '' }
+fr.json: { 'hello': '' }
+de.json: { 'hello': '' }
+```
+
+❌ Example of an **incorrect** setup for this rule (some locales have empty messages):
+
+```js
+en.json: { 'hello': '' }
+fr.json: { 'hello': 'Salut!' }
+de.json: { 'hello': 'Hi!' }
+```
+
+✅ Examples of a **correct** setup for this rule (all messages are non-empty):
+
+```js
+en.json: { 'hello': 'Hi!' }
+fr.json: { 'hello': 'Salut!' }
+de.json: { 'hello': 'Hallo!' }
+```
+
+## Example Configuration
+
+```json
+{
+	"rules": {
+		"no-empty-messages": "error"
+	}
+}
+```
+
+## Version
+
+This rule was introduced in i18n-validator v1.0.0.

src/rules/no-empty-messages/index.ts

@@ -0,0 +1 @@
+export { noEmptyMessages } from "./no-empty-messages.ts";

src/rules/no-empty-messages/no-empty-messages.spec.ts

@@ -0,0 +1,108 @@
+import { createMockProblemReporter } from "../../tests/utils/test-helpers.ts";
+import {
+	Config,
+	RuleContext,
+	RuleSeverity,
+	TranslationFiles,
+} from "../../types.ts";
+import { noEmptyMessages } from "./no-empty-messages.ts";
+import {
+	getEmptySourceMessageProblem,
+	getEmptyTranslatedMessageProblem,
+} from "./problems.ts";
+
+const ruleMeta = noEmptyMessages.meta;
+const rule = noEmptyMessages;
+
+const defaultLocale = "en";
+
+const baseConfig: Config = {
+	defaultLocale,
+	sourceFile: "en.json",
+	translationFiles: { fr: "fr.json" },
+	pathToTranslatedFiles: "i18n",
+	rules: {
+		"no-empty-messages": "error",
+	},
+	dryRun: false,
+	enabled: true,
+};
+
+describe.each([["error"], ["warning"]])(`${rule.meta.name}`, (severity) => {
+	const context: RuleContext = {
+		severity: severity as RuleSeverity,
+	};
+
+	it(`should report empty messages in the source file with severity: ${severity}`, () => {
+		const problemReporter = createMockProblemReporter();
+
+		const translationFiles: TranslationFiles = {
+			en: { greeting: "Hello", empty: "" },
+			fr: { greeting: "Bonjour", empty: "not empty" },
+		};
+
+		rule.run(translationFiles, baseConfig, problemReporter, context);
+
+		const expectedProblem = getEmptySourceMessageProblem({
+			key: "empty",
+			locale: "en",
+			severity: severity as RuleSeverity,
+			ruleMeta,
+		});
+
+		expect(problemReporter.report).toHaveBeenCalledWith(expectedProblem);
+		expect(problemReporter.report).toHaveBeenCalledTimes(1);
+	});
+
+	it(`should report empty messages in translation file with severity: ${severity}`, () => {
+		const problemReporter = createMockProblemReporter();
+
+		const translationFiles: TranslationFiles = {
+			en: { greeting: "Hello", empty: "not empty" },
+			fr: { greeting: "Bonjour", empty: "" },
+		};
+
+		rule.run(translationFiles, baseConfig, problemReporter, context);
+
+		const expectedProblem = getEmptyTranslatedMessageProblem({
+			key: "empty",
+			locale: "fr",
+			severity: severity as RuleSeverity,
+			ruleMeta,
+		});
+
+		expect(problemReporter.report).toHaveBeenCalledWith(expectedProblem);
+		expect(problemReporter.report).toHaveBeenCalledTimes(1);
+	});
+
+	it("should not report non-empty messages", () => {
+		const problemReporter = createMockProblemReporter();
+
+		const translationFiles: TranslationFiles = {
+			en: { greeting: "Hello", farewell: "Goodbye" },
+			fr: { greeting: "Bonjour", farewell: "Au revoir" },
+		};
+
+		rule.run(translationFiles, baseConfig, problemReporter, context);
+
+		expect(problemReporter.report).not.toHaveBeenCalled();
+	});
+});
+
+describe(`${rule.meta.name}: off`, () => {
+	it("should not report problems when severity = off", () => {
+		const problemReporter = createMockProblemReporter();
+
+		const context: RuleContext = {
+			severity: "off",
+		};
+
+		const translationFiles: TranslationFiles = {
+			en: { greeting: "Hello", empty: "" },
+			fr: { greeting: "Bonjour", empty: "" },
+		};
+
+		rule.run(translationFiles, baseConfig, problemReporter, context);
+		expect(problemReporter.report).not.toHaveBeenCalled();
+	});
+});

src/rules/no-empty-messages/no-empty-messages.ts

@@ -0,0 +1,65 @@
+import { SEVERITY_LEVEL } from "../../constants.ts";
+import {
+	Config,
+	Rule,
+	RuleContext,
+	RuleMeta,
+	TranslationFiles,
+} from "../../types.ts";
+import {
+	getEmptySourceMessageProblem,
+	getEmptyTranslatedMessageProblem,
+} from "./problems.ts";
+
+const ruleMeta: RuleMeta = {
+	name: "no-empty-messages",
+	description: `Checks for empty messages in translations.`,
+	url: "TBD",
+	type: "validation",
+	defaultSeverity: "error",
+};
+
+const noEmptyMessages: Rule = {
+	meta: ruleMeta,
+	run: (
+		translationFiles: TranslationFiles,
+		config: Config,
+		problemReporter,
+		context: RuleContext
+	) => {
+		const { defaultLocale } = config;
+		const { severity } = context;
+		const baseLocale = translationFiles[defaultLocale];
+
+		if (severity === SEVERITY_LEVEL.off) {
+			return;
+		}
+
+		for (const [locale, data] of Object.entries(translationFiles)) {
+			for (const [key, message] of Object.entries(data)) {
+				const baseMessage = baseLocale[key].trim();
+
+				const hasEmptyBaseMessage = locale === defaultLocale && !baseMessage;
+				const hasEmptyTranslation =
+					locale !== defaultLocale && message.trim() === "";
+
+				if (hasEmptyBaseMessage) {
+					problemReporter.report(
+						getEmptySourceMessageProblem({ key, locale, severity, ruleMeta })
+					);
+				} else if (hasEmptyTranslation) {
+					problemReporter.report(
+						getEmptyTranslatedMessageProblem({
+							key,
+							locale,
+							severity,
+							ruleMeta,
+						})
+					);
+				}
+			}
+		}
+	},
+};
+
+export { noEmptyMessages };

src/rules/no-empty-messages/problems.ts

@@ -0,0 +1,33 @@
+import { Problem } from "../../classes/problem.class.ts";
+import { RuleMeta, RuleSeverity } from "../../types.ts";
+
+type ProblemContext = {
+	key: string;
+	locale: string;
+	severity: RuleSeverity;
+	ruleMeta: RuleMeta;
+};
+
+export function getEmptySourceMessageProblem(
+	problemContext: ProblemContext
+): Problem {
+	const { key, locale, severity, ruleMeta } = problemContext;
+
+	return Problem.Builder.withRuleMeta(ruleMeta)
+		.withSeverity(severity)
+		.withLocale(locale)
+		.withMessage(`Empty message found in source key: ${key}`)
+		.build();
+}
+
+export function getEmptyTranslatedMessageProblem(
+	problemContext: ProblemContext
+): Problem {
+	const { key, locale, severity, ruleMeta } = problemContext;
+
+	return Problem.Builder.withRuleMeta(ruleMeta)
+		.withSeverity(severity)
+		.withLocale(locale)
+		.withMessage(`Empty message found in translated key: ${key}`)
+		.build();
+}

src/rules/no-untranslated-messages/README.md

@@ -32,6 +32,16 @@ fr.json: { 'hello': 'Salut!' }
 de.json: { 'hello': 'Hallo!' }
 ```
 
+## Example Configuration
+
+```json
+{
+	"rules": {
+		"no-untranslated-messages": "error"
+	}
+}
+```
+
 ## Version
 
 This rule was introduced in i18n-validator v1.0.0.

src/tests/fixtures/i18n/de.json

@@ -1,3 +1,5 @@
 {
-  "hi": "Hi!"
+	"untranslated-message": "Hi!",
+	"empty-string": "",
+	"only-empty-in-en": "[DE] not empty"
 }

src/tests/fixtures/i18n/en.json

@@ -1,3 +1,5 @@
 {
-  "hi": "Hi!"
+	"untranslated-message": "Hi!",
+	"empty-string": "",
+	"only-empty-in-en": ""
 }

src/tests/fixtures/i18n/fr.json

@@ -1,3 +1,5 @@
 {
-  "hi": "Hi!"
+	"untranslated-message": "Hi!",
+	"empty-string": "",
+	"only-empty-in-en": "[FR] not empty"
 }

src/utils/config-helpers.ts

@@ -1,4 +1,4 @@
-import { Config } from "../types.ts";
+import type { Config } from "../types";
 
 export function getAllSupportedLocales(config: Config): string[] {
 	const allSupportedLocales = new Set([