Feat: Ensure markdown formatting (#34547)

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Closes #34535

tools/scripts/ci/ensure-challenge-formatting.js

@@ -0,0 +1,77 @@
+const readdirp = require('readdirp-walk');
+const { has, isEmpty, isNumber } = require('lodash');
+const ora = require('ora');
+
+const { parseMarkdown } = require('../../challenge-md-parser');
+const { challengeRoot, checkFrontmatter } = require('./md-testing-utils');
+
+const scrimbaUrlRE = /^https:\/\/scrimba\.com\//;
+const requiredProps = ['title', 'id', 'challengeType'];
+
+const spinner = ora('Checking challenge markdown formatting').start();
+
+readdirp({ root: challengeRoot, directoryFilter: '!_meta' })
+  .on('data', file =>
+    Promise.all([
+      isChallengeParseable(file),
+      checkFrontmatter(file, {
+        validator: challengeFrontmatterValidator(file)
+      })
+    ]).catch(err => {
+      console.info(`
+  the following error occured when testing
+
+    ${file.fullPath}
+
+    `);
+      console.error(err);
+      // eslint-disable-next-line no-process-exit
+      process.exit(1);
+    })
+  )
+  .on('end', () => spinner.stop());
+
+const challengeFrontmatterValidator = file => frontmatter => {
+  const { fullPath } = file;
+
+  const hasRequiredProperties = requiredProps
+    .map(
+      prop =>
+        has(frontmatter, prop) &&
+        (!isEmpty(frontmatter[prop]) || isNumber(frontmatter[prop]))
+    )
+    .every(bool => bool);
+
+  if (!hasRequiredProperties) {
+    console.log(`${fullPath} is missing required frontmatter
+
+    ${JSON.stringify(frontmatter, null, 2)}
+
+    Required properties are: ${JSON.stringify(requiredProps, null, 2)}
+
+    `);
+  }
+  const { videoUrl } = frontmatter;
+
+  let validVideoUrl = false;
+  if (isEmpty(videoUrl)) {
+    validVideoUrl = true;
+  } else {
+    validVideoUrl = scrimbaUrlRE.test(videoUrl);
+
+    if (!validVideoUrl) {
+      console.log(`
+  ${fullPath} contains an invalid videoUrl
+`);
+    }
+  }
+  return hasRequiredProperties && validVideoUrl;
+};
+
+function isChallengeParseable(file) {
+  const { stat, fullPath } = file;
+  if (!stat.isFile() || (/_meta/).test(fullPath)) {
+    return Promise.resolve(true);
+  }
+  return parseMarkdown(fullPath);
+}