1 files changed, 29 insertions, 0 deletions
diff --git a/spec/frontend/vue_shared/components/source_viewer/plugins/wrap_comments_spec.js b/spec/frontend/vue_shared/components/source_viewer/plugins/wrap_comments_spec.js
new file mode 100644
index 00000000000..5fd4182da29
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+++ b/spec/frontend/vue_shared/components/source_viewer/plugins/wrap_comments_spec.js
@@ -0,0 +1,29 @@
+import { HLJS_COMMENT_SELECTOR } from '~/vue_shared/components/source_viewer/constants';
+import wrapComments from '~/vue_shared/components/source_viewer/plugins/wrap_comments';
+
+describe('Highlight.js plugin for wrapping comments', () => {
+  it('mutates the input value by wrapping each line in a span tag', () => {
+    const inputValue = `<span class="${HLJS_COMMENT_SELECTOR}">/* Line 1 \n* Line 2 \n*/</span>`;
+    const outputValue = `<span class="${HLJS_COMMENT_SELECTOR}">/* Line 1 \n<span class="${HLJS_COMMENT_SELECTOR}">* Line 2 </span>\n<span class="${HLJS_COMMENT_SELECTOR}">*/</span>`;
+    const hljsResultMock = { value: inputValue };
+
+    wrapComments(hljsResultMock);
+    expect(hljsResultMock.value).toBe(outputValue);
+  });
+
+  it('does not mutate the input value if the hljs comment selector is not present', () => {
+    const inputValue = '<span class="hljs-keyword">const</span>';
+    const hljsResultMock = { value: inputValue };
+
+    wrapComments(hljsResultMock);
+    expect(hljsResultMock.value).toBe(inputValue);
+  });
+
+  it('does not mutate the input value if the hljs comment line includes a closing tag', () => {
+    const inputValue = `<span class="${HLJS_COMMENT_SELECTOR}">/* Line 1 </span> \n* Line 2 \n*/`;
+    const hljsResultMock = { value: inputValue };
+
+    wrapComments(hljsResultMock);
+    expect(hljsResultMock.value).toBe(inputValue);
+  });
+});