Keep JS blocks that follow a block in another language

CHANGELOG.md

@@ -17,6 +17,11 @@
   repeating the same rejected request.
 - [Apibot] API test scenarios no longer mutate or delete records discovered as sample data. Chief plans a
   scenario-owned target for destructive checks, and Curler stops when it cannot create one safely.
+- [Navigator] A verification is no longer reported as impossible to express when the answer shows a
+  snippet of page markup before its assertions. A code block written in any language other than
+  JavaScript used to shift the reading of every later block, so all the assertions the model had
+  written were dropped and a claim it had answered correctly came back as one no assertion could
+  express.
 - A batch of browser commands now reports every command it ran. CodeceptJS hands a passing step its own
   return value, which was read as an error, so the first command of every successful batch was reported
   as failed with `[object Promise]` and the commands after it were left out of the report entirely. A

src/utils/code-extractor.ts

@@ -2,13 +2,17 @@ import { createDebug } from './logger.js';
 
 const debugLog = createDebug('explorbot:code-extractor');
 
+const JS_LANGUAGES = new Set(['', 'js', 'javascript']);
+
 export function extractCodeBlocks(aiResponse: string): string[] {
-  const codeBlockRegex = /```(?:js|javascript)?\s*\n([\s\S]*?)\n```/g;
+  const codeBlockRegex = /```([^\n`]*)\n([\s\S]*?)\n```/g;
   const codeBlocks: string[] = [];
   let match: RegExpExecArray | null = null;
 
   while ((match = codeBlockRegex.exec(aiResponse))) {
-    const code = match[1].trim();
+    const language = match[1].trim().toLowerCase();
+    if (!JS_LANGUAGES.has(language)) continue;
+    const code = match[2].trim();
     if (!code) continue;
     try {
       new Function('I', code);

tests/unit/code-extractor.test.ts

@@ -0,0 +1,67 @@
+import { describe, expect, it } from 'bun:test';
+import dedent from 'dedent';
+import { extractCodeBlocks } from '../../src/utils/code-extractor.ts';
+
+describe('extractCodeBlocks', () => {
+  it('extracts a js block', () => {
+    const response = dedent`
+      \`\`\`js
+      I.see('Widget', '.list')
+      \`\`\`
+    `;
+
+    expect(extractCodeBlocks(response)).toEqual(["I.see('Widget', '.list')"]);
+  });
+
+  it('extracts an unlabelled block', () => {
+    const response = dedent`
+      \`\`\`
+      I.see('Widget', '.list')
+      \`\`\`
+    `;
+
+    expect(extractCodeBlocks(response)).toEqual(["I.see('Widget', '.list')"]);
+  });
+
+  it('keeps js blocks that follow a block in another language', () => {
+    const response = dedent`
+      The element is rendered as:
+
+      \`\`\`html
+      <a class="node-link"><span>Widget</span><small>0 tests</small></a>
+      \`\`\`
+
+      ### 1. Verify by visible text
+      \`\`\`js
+      I.see('Widget 0 tests', '.list')
+      \`\`\`
+
+      ### 2. Verify by selector
+      \`\`\`js
+      I.seeElement('.list a[href*="widget"]')
+      \`\`\`
+    `;
+
+    expect(extractCodeBlocks(response)).toEqual(["I.see('Widget 0 tests', '.list')", 'I.seeElement(\'.list a[href*="widget"]\')']);
+  });
+
+  it('skips a block in another language even when its content parses as javascript', () => {
+    const response = dedent`
+      \`\`\`text
+      Saved
+      \`\`\`
+    `;
+
+    expect(extractCodeBlocks(response)).toEqual([]);
+  });
+
+  it('skips a js block that is not valid javascript', () => {
+    const response = dedent`
+      \`\`\`js
+      I.see('Widget'
+      \`\`\`
+    `;
+
+    expect(extractCodeBlocks(response)).toEqual([]);
+  });
+});