⚡ Add home-brewed i18n coverage reports and language file checkers to CI

gulpfile.js

@@ -204,7 +204,9 @@ const lintJS = () => {
     .pipe(eslint.failAfterError());
 };
 
-const lint = gulp.series(lintJS, lintStylus);
+const lintI18n = () => require('./node_requires/i18n')().then(console.log);
+
+const lint = gulp.series(lintJS, lintStylus, lintI18n);
 
 const launchApp = () => {
     spawnise.spawn(npm, ['run', 'start'], {

node_requires/i18n/index.js

@@ -0,0 +1,118 @@
+const i18nDir = './../../app/data/i18n';
+const path = require('path'),
+      fs = require('fs-extra');
+const referenceLanguage = require(path.join(i18nDir, 'English.json'));
+
+const recursiveCountRemainingFields = node => {
+    if (typeof node === 'string') {
+        return 1;
+    }
+    let counted = 0;
+    for (const i in node) {
+        counted += recursiveCountRemainingFields(node[i]);
+    }
+    return counted;
+};
+
+// Recursively counts keys in English.json, translated keys,
+// and collects paths to untranslated and excess keys
+const recursiveCheck = function(partial, langNode, referenceNode) {
+    const untranslated = [],
+          excess = [];
+    let counted = 0,
+        needed = 0;
+    for (const i in referenceNode) {
+        if (typeof referenceNode[i] === 'string') {
+            needed++;
+            if (!(i in langNode) || langNode[i].trim() === '') {
+                untranslated.push(partial? `${partial}.${i}` : i);
+            } else {
+                counted++;
+            }
+        } else if (i in langNode) {
+            const subresults = recursiveCheck(partial? `${partial}.${i}` : i, langNode[i], referenceNode[i]);
+            if (subresults.untranslated.length) {
+                untranslated.push(...subresults.untranslated);
+            }
+            if (subresults.excess.length) {
+                excess.push(...subresults.excess);
+            }
+            counted += subresults.counted;
+            needed += subresults.needed;
+        } else {
+            untranslated.push(partial? `${partial}.${i}` : i);
+            needed += recursiveCountRemainingFields(referenceNode[i]);
+        }
+    }
+    // Reverse check to catch excess keys
+    // that are not present in English.json but are in another language file
+    for (const i in langNode) {
+        if (!(i in referenceNode) || (typeof referenceNode[i] === 'string' && referenceNode[i].trim() === '')) {
+            excess.push(partial? `${partial}.${i}` : i);
+        }
+    }
+    return {
+        untranslated,
+        excess,
+        counted,
+        needed
+    };
+};
+
+const breakpoints = [
+    [95, '👏  Fabulous!'],
+    [85, '✅  Good!'],
+    [70, '😕  A decent coverage, but it could be better!'],
+    [50, '👎  Meh'],
+    [0, '🆘  Someone help, please!']
+];
+const getSuitableBreakpoint = percent => {
+    for (const point of breakpoints) {
+        if (percent >= point[0]) {
+            return point[1];
+        }
+    }
+    return 'WTF?';
+};
+
+module.exports = async () => {
+    const fileNames = (await fs.readdir('./app/data/i18n')).filter(file =>
+        path.extname(file) === '.json' &&
+        file !== 'Comments.json' &&
+        file !== 'English.json' &&
+        file !== 'Debug.json'
+    );
+    const report = {
+        untranslated: {},
+        excess: {},
+        stats: {}
+    };
+    for (const lang of fileNames) {
+        const rootNode = require(path.join(i18nDir, lang));
+        const result = recursiveCheck('', rootNode, referenceLanguage);
+        report.untranslated[lang] = result.untranslated;
+        report.excess[lang] = result.excess;
+        report.stats[lang] = Math.floor(result.counted / result.needed * 100);
+    }
+    const reportText =
+
+`\nTranslation report:
+===================\n\n` + fileNames.map(lang =>
+`Translation file ${lang}
+-----------------${'-'.repeat(lang.length)}\n` +
+// eslint-disable-next-line no-nested-ternary
+`Coverage: ${report.stats[lang]}% ${getSuitableBreakpoint(report.stats[lang])}
+Not translated: ${report.untranslated[lang].length}` +
+(report.untranslated[lang].length > 0? '\n'+report.untranslated[lang].map(key => `  ${key}`).join('\n') : '') +
+`\nExcess: ${report.excess[lang].length} ${report.excess[lang].length? '⚠️ '.repeat(Math.min(10, report.excess[lang].length)) : '✅'}\n` +
+(report.excess[lang].length > 0? report.excess[lang].map(key => `  ${key}`).join('\n') : '')
+
+).join('\n\n');
+
+    for (const lang in report.excess) {
+        if (report.excess[lang].length) {
+            throw new Error(reportText);
+        }
+    }
+    return reportText;
+};