first run

scripts/generateHeaderIDs.js

@@ -0,0 +1,64 @@
+const fs = require('fs');
+
+function walk(dir) {
+  let results = [];
+  const list = fs.readdirSync(dir);
+  list.forEach(function(file) {
+    file = dir + '/' + file;
+    const stat = fs.statSync(file);
+    if (stat && stat.isDirectory()) {
+      /* Recurse into a subdirectory */
+      results = results.concat(walk(file));
+    } else {
+      /* Is a file */
+      results.push(file);
+    }
+  });
+  return results;
+}
+
+function generateID(text) {
+  return text
+    .toLowerCase()
+    .replace(/\s/g, '-')
+    .replace(/[^-a-z0-9]/g, '');
+}
+
+function addHeaderID(line) {
+  // check if we're a header at all
+  if (!line.startsWith('#')) return;
+  // check if it already has an id
+  if (/\{#[-A-Za-z0-9]+\}/.match(line)) return;
+  const headingText = line.slice(line.indexOf(' ')).trim();
+  const headingLevel = line.slice(0, line.indexOf(' '));
+  return `${headingLevel} ${headingText} ${generateID(headingText)}`;
+}
+
+function addHeaderIDs(lines) {
+  let inCode = false;
+  const results = [];
+  lines.forEach(line => {
+    // Ignore code blocks
+    if (line.startsWith('```')) {
+      inCode = !inCode;
+      return;
+    }
+    if (inCode) {
+      results.push(line);
+    }
+
+    results.push(addHeaderID(line));
+  });
+}
+
+const [path] = process.argv.slice(2);
+
+const files = walk(path);
+files.forEach(file => {
+  if (!file.endsWith('.md')) return;
+
+  const file = fs.readFileSync(file, 'utf8');
+  const lines = file.split('\n');
+  const updatedLines = addHeaderIDs(lines);
+  fs.writeFileSync(file, updatedLines.join('\n'));
+});