feat: parse translated challenges

Using the English challenge as a source for the seed, solution and tests
this takes the parts that can be translated from the translated version
of the challenge. It also translates known comments in the seed.

tools/challenge-md-parser/translation-parser/translation-parser.js

@@ -0,0 +1,102 @@
+const clone = require('lodash/cloneDeep');
+
+exports.translateComments = (text, lang, dict, codeLang) => {
+  const knownComments = Object.keys(dict);
+  const config = { knownComments, dict, lang };
+  switch (codeLang) {
+    case 'js':
+      return transMultiline(transInline(text, config), config);
+    case 'jsx':
+      return transJSX(text, config);
+    case 'html':
+      return transHTML(transCSS(text, config), config);
+    default:
+      return text;
+  }
+};
+
+exports.translateCommentsInChallenge = (challenge, lang, dict, codeLang) => {
+  const challClone = clone(challenge);
+
+  if (challClone.files[0] && challClone.files[0].contents) {
+    challClone.files[0].contents = this.translateComments(
+      challenge.files[0].contents,
+      lang,
+      dict,
+      codeLang
+    );
+  }
+
+  return challClone;
+};
+
+exports.mergeChallenges = (engChal, transChal) => {
+  if (!transChal.tests || transChal.tests.length !== engChal.tests.length)
+    throw Error(
+      `Challenges in both languages must have the same number of tests.
+    title: ${engChal.title}
+    localeTitle: ${transChal.localeTitle}`
+    );
+  const translatedTests = transChal.tests.map(({ text }, id) => ({
+    text,
+    testString: engChal.tests[id].testString
+  }));
+  return {
+    ...engChal,
+    description: transChal.description,
+    instructions: transChal.instructions,
+    localeTitle: transChal.localeTitle,
+    forumTopicId: transChal.forumTopicId,
+    tests: translatedTests
+  };
+};
+
+// bare urls could be interpreted as comments, so we have to lookbehind for
+// http:// or https://
+function transInline(text, config) {
+  return translateGeneric(
+    text,
+    config,
+    '(^[^\'"`]*?(?<!https?:)//\\s*)',
+    '(\\s*$)'
+  );
+}
+
+function transMultiline(text, config) {
+  return translateGeneric(text, config, '(/\\*\\s*)', '(\\s*\\*/)');
+}
+
+// CSS has to be handled separately since it is looking for comments inside tags
+function transCSS(text, config) {
+  const regex = /<style>.*?<\/style>/gms;
+  const matches = text.matchAll(regex);
+
+  for (const [match] of matches) {
+    text = text.replace(match, transMultiline(match, config));
+  }
+  return text;
+}
+
+function transJSX(text, config) {
+  return translateGeneric(text, config, '({[^}]*/\\*\\s*)', '(\\s*\\*/[^{]*})');
+}
+
+function transHTML(text, config) {
+  return translateGeneric(text, config, '(<!--\\s*)', '(\\s*-->)');
+}
+
+function translateGeneric(text, config, regexBefore, regexAfter) {
+  const { knownComments, dict, lang } = config;
+  const regex = new RegExp(regexBefore + '(.*?)' + regexAfter, 'gms');
+  const matches = text.matchAll(regex);
+
+  for (const [match, before, comment, after] of matches) {
+    if (knownComments.includes(comment)) {
+      text = text.replace(match, `${before}${dict[comment][lang]}${after}`);
+    } else {
+      console.warn(`${comment} does not appear in the comment dictionary`);
+    }
+  }
+
+  return text;
+}