Add PR job that checks changed token files

.github/workflows/check-tokens.yml

@@ -0,0 +1,25 @@
+name: Check tokens
+
+on:
+  pull_request:
+    branches: [main]
+
+jobs:
+  check:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      - uses: actions/setup-node@v4
+        with:
+          node-version: '24'
+
+      - name: Check changed token files
+        env:
+          BASE_SHA: ${{ github.event.pull_request.base.sha }}
+        run: |
+          files=$(git diff --name-only --no-renames "$BASE_SHA"...HEAD -- 'tokensStudio/**/*.json')
+          [ -n "$files" ] || { echo "No token files changed"; exit 0; }
+          echo "$files" | xargs node scripts/check-changed-tokens.js

scripts/check-changed-tokens.js

@@ -0,0 +1,69 @@
+import { readFileSync } from 'fs'
+import { execFileSync } from 'child_process'
+
+const baseSha = process.env.BASE_SHA
+const files = process.argv.slice(2)
+
+// Content on the base branch; missing means the PR added the file.
+const readBase = (file) => {
+  try {
+    return execFileSync('git', ['show', `${baseSha}:${file}`], {
+      encoding: 'utf8',
+      stdio: ['ignore', 'pipe', 'ignore']
+    })
+  } catch {
+    return null
+  }
+}
+
+// Content on this PR; missing means the PR deleted the file.
+const readHead = (file) => {
+  try {
+    return readFileSync(file, 'utf8')
+  } catch {
+    return null
+  }
+}
+
+const getMissingTokens = (base, head) => {
+  const missingTokens = [];
+
+  const isLeaf = (obj) =>
+    !!obj && typeof obj === "object" && "value" in obj && "type" in obj;
+  const crawlObject = (base, head, path) => {
+    const keys = Object.keys(base);
+    for (let i = 0; i < keys.length; i++) {
+      const key = keys[i];
+      if (!isLeaf(base) && !!head[key]) {
+        crawlObject(base[key], head[key], `${path ? path + "." : ""}${key}`);
+      }
+      if (!isLeaf(base) && !head[key]) {
+        missingTokens.push(`${path ? path + "." : ""}${key}`);
+      }
+    }
+  };
+
+  crawlObject(base, head, "");
+  return missingTokens;
+};
+
+for (const file of files) {
+  const base = readBase(file);
+  const head = readHead(file);
+  const status =
+    base === null ? "added" : head === null ? "deleted" : "modified";
+
+  if (status === "deleted") {
+    console.log(`File was deleted: ${file}`);
+    process.exitCode = 1;
+  }
+
+  if (status === "modified") {
+    const missingTokens = getMissingTokens(JSON.parse(base), JSON.parse(head));
+    if (missingTokens.length > 0) {
+      console.log(`missing token(s) from ${file}:`);
+      missingTokens.forEach((token) => console.log(token));
+      process.exitCode = 1;
+    }
+  }
+}