feat(client): support beforeAll in DOM challenge tests (#59001)

tools/challenge-parser/parser/__fixtures__/with-another-invalid-before-hook.md

@@ -0,0 +1,34 @@
+# --description--
+
+Paragraph 1
+
+```html
+code example
+```
+
+# --before-all--
+
+gubbins
+
+# --hints--
+
+First hint
+
+```js
+// test code
+```
+
+Second hint with <code>code</code>
+
+```js
+// more test code
+```
+
+Third *hint* with <code>code</code> and `inline code`
+
+```js
+// more test code
+if(let x of xs) {
+  console.log(x);
+}
+```

tools/challenge-parser/parser/__fixtures__/with-before-hook.md

@@ -0,0 +1,40 @@
+# --description--
+
+Paragraph 1
+
+```html
+code example
+```
+
+# --before-all--
+
+```js
+// before all code
+function foo() {
+  return 'bar';
+}
+foo();
+```
+
+# --hints--
+
+First hint
+
+```js
+// test code
+```
+
+Second hint with <code>code</code>
+
+```js
+// more test code
+```
+
+Third *hint* with <code>code</code> and `inline code`
+
+```js
+// more test code
+if(let x of xs) {
+  console.log(x);
+}
+```

tools/challenge-parser/parser/__fixtures__/with-empty-before-hook.md

@@ -0,0 +1,32 @@
+# --description--
+
+Paragraph 1
+
+```html
+code example
+```
+
+# --before-all--
+
+# --hints--
+
+First hint
+
+```js
+// test code
+```
+
+Second hint with <code>code</code>
+
+```js
+// more test code
+```
+
+Third *hint* with <code>code</code> and `inline code`
+
+```js
+// more test code
+if(let x of xs) {
+  console.log(x);
+}
+```

tools/challenge-parser/parser/__fixtures__/with-invalid-before-hook.md

@@ -0,0 +1,42 @@
+# --description--
+
+Paragraph 1
+
+```html
+code example
+```
+
+# --before-all--
+
+```js
+// before all code
+function foo() {
+  return 'bar';
+}
+foo();
+```
+
+gubbins
+
+# --hints--
+
+First hint
+
+```js
+// test code
+```
+
+Second hint with <code>code</code>
+
+```js
+// more test code
+```
+
+Third *hint* with <code>code</code> and `inline code`
+
+```js
+// more test code
+if(let x of xs) {
+  console.log(x);
+}
+```

tools/challenge-parser/parser/__fixtures__/with-non-js-before-hook.md

@@ -0,0 +1,40 @@
+# --description--
+
+Paragraph 1
+
+```html
+code example
+```
+
+# --before-all--
+
+```ts
+// before all code
+function foo() {
+  return 'bar';
+}
+foo();
+```
+
+# --hints--
+
+First hint
+
+```js
+// test code
+```
+
+Second hint with <code>code</code>
+
+```js
+// more test code
+```
+
+Third *hint* with <code>code</code> and `inline code`
+
+```js
+// more test code
+if(let x of xs) {
+  console.log(x);
+}
+```

tools/challenge-parser/parser/index.js

@@ -7,6 +7,7 @@ const addFillInTheBlank = require('./plugins/add-fill-in-the-blank');
 const addFrontmatter = require('./plugins/add-frontmatter');
 const addSeed = require('./plugins/add-seed');
 const addSolution = require('./plugins/add-solution');
+const addBeforeHook = require('./plugins/add-before-hook');
 const addTests = require('./plugins/add-tests');
 const addText = require('./plugins/add-text');
 const addVideoQuestion = require('./plugins/add-video-question');
@@ -52,6 +53,7 @@ const processor = unified()
   .use(addAssignment)
   .use(addScene)
   .use(addQuizzes)
+  .use(addBeforeHook)
   .use(addTests)
   .use(addText, [
     'description',

tools/challenge-parser/parser/plugins/__snapshots__/add-before-hook.test.js.snap

@@ -0,0 +1,13 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`add-before-hook plugin should have an output to match the snapshot 1`] = `
+{
+  "hooks": {
+    "beforeAll": "// before all code
+function foo() {
+  return 'bar';
+}
+foo();",
+  },
+}
+`;

tools/challenge-parser/parser/plugins/add-before-hook.js

@@ -0,0 +1,33 @@
+const { getSection } = require('./utils/get-section');
+
+function plugin() {
+  return transformer;
+
+  function transformer(tree, file) {
+    const section = getSection(tree, '--before-all--');
+
+    if (section.length === 0) return;
+    if (section.length > 1)
+      throw Error(
+        '#--before-all-- section must only contain a single code block'
+      );
+
+    const codeNode = section[0];
+
+    if (codeNode.type !== 'code')
+      throw Error('#--before-all-- section must contain a code block');
+    if (codeNode.lang !== 'javascript' && codeNode.lang !== 'js')
+      throw Error('#--before-all-- hook must be written in JavaScript');
+
+    const beforeAll = getBeforeAll(codeNode);
+    file.data.hooks = { beforeAll };
+  }
+}
+
+function getBeforeAll(codeNode) {
+  const beforeAll = codeNode.value;
+
+  return beforeAll;
+}
+
+module.exports = plugin;

tools/challenge-parser/parser/plugins/add-before-hook.test.js

@@ -0,0 +1,69 @@
+const parseFixture = require('../__fixtures__/parse-fixture');
+
+const addBeforeHook = require('./add-before-hook');
+
+describe('add-before-hook plugin', () => {
+  let withBeforeHookAST,
+    withEmptyHookAST,
+    withInvalidHookAST,
+    withAnotherInvalidHookAST,
+    withNonJSHookAST;
+
+  const plugin = addBeforeHook();
+  let file = { data: {} };
+
+  beforeAll(async () => {
+    withBeforeHookAST = await parseFixture('with-before-hook.md');
+    withEmptyHookAST = await parseFixture('with-empty-before-hook.md');
+    withInvalidHookAST = await parseFixture('with-invalid-before-hook.md');
+    withAnotherInvalidHookAST = await parseFixture(
+      'with-another-invalid-before-hook.md'
+    );
+    withNonJSHookAST = await parseFixture('with-non-js-before-hook.md');
+  });
+
+  beforeEach(() => {
+    file = { data: {} };
+  });
+
+  it('returns a function', () => {
+    expect(typeof plugin).toEqual('function');
+  });
+
+  it('adds a `hooks` property to `file.data`', () => {
+    plugin(withBeforeHookAST, file);
+    expect('hooks' in file.data).toBe(true);
+  });
+
+  it('populates `hooks.beforeAll` with the contents of the code block', () => {
+    plugin(withBeforeHookAST, file);
+    expect(file.data.hooks.beforeAll).toBe(`// before all code
+function foo() {
+  return 'bar';
+}
+foo();`);
+  });
+
+  it('should throw an error if the beforeAll section has more than one child', () => {
+    expect(() => plugin(withInvalidHookAST, file)).toThrow(
+      `#--before-all-- section must only contain a single code block`
+    );
+  });
+
+  it('should throw an error if the beforeAll section does not contain a code block', () => {
+    expect(() => plugin(withAnotherInvalidHookAST, file)).toThrow(
+      `#--before-all-- section must contain a code block`
+    );
+  });
+
+  it('should throw an error if the code language is not javascript', () => {
+    expect(() => plugin(withNonJSHookAST, file)).toThrow(
+      `#--before-all-- hook must be written in JavaScript`
+    );
+  });
+
+  it('should have an output to match the snapshot', () => {
+    plugin(withBeforeHookAST, file);
+    expect(file.data).toMatchSnapshot();
+  });
+});