1 files changed, 134 insertions, 0 deletions
diff --git a/spec/frontend/snippets/utils/blob_spec.js b/spec/frontend/snippets/utils/blob_spec.js
new file mode 100644
index 00000000000..ba39b9fec36
--- /dev/null
+++ b/spec/frontend/snippets/utils/blob_spec.js
@@ -0,0 +1,134 @@
+import { cloneDeep } from 'lodash';
+import {
+  SNIPPET_BLOB_ACTION_CREATE,
+  SNIPPET_BLOB_ACTION_UPDATE,
+  SNIPPET_BLOB_ACTION_MOVE,
+  SNIPPET_BLOB_ACTION_DELETE,
+} from '~/snippets/constants';
+import { decorateBlob, createBlob, diffAll } from '~/snippets/utils/blob';
+
+jest.mock('lodash/uniqueId', () => arg => `${arg}fakeUniqueId`);
+
+const TEST_RAW_BLOB = {
+  rawPath: '/test/blob/7/raw',
+};
+const CONTENT_1 = 'Lorem ipsum dolar\nSit amit\n\nGoodbye!\n';
+const CONTENT_2 = 'Lorem ipsum dolar sit amit.\n\nGoodbye!\n';
+
+describe('~/snippets/utils/blob', () => {
+  describe('decorateBlob', () => {
+    it('should decorate the given object with local blob properties', () => {
+      const orig = cloneDeep(TEST_RAW_BLOB);
+
+      expect(decorateBlob(orig)).toEqual({
+        ...TEST_RAW_BLOB,
+        id: 'blob_local_fakeUniqueId',
+        isLoaded: false,
+        content: '',
+      });
+    });
+  });
+
+  describe('createBlob', () => {
+    it('should create an empty local blob', () => {
+      expect(createBlob()).toEqual({
+        id: 'blob_local_fakeUniqueId',
+        isLoaded: true,
+        content: '',
+        path: '',
+      });
+    });
+  });
+
+  describe('diffAll', () => {
+    // This object contains entries that contain an expected "diff" and the `id`
+    // or `origContent` that should be used to generate the expected diff.
+    const testEntries = {
+      created: {
+        id: 'blob_1',
+        diff: {
+          action: SNIPPET_BLOB_ACTION_CREATE,
+          filePath: '/new/file',
+          previousPath: '/new/file',
+          content: CONTENT_1,
+        },
+      },
+      deleted: {
+        id: 'blob_2',
+        diff: {
+          action: SNIPPET_BLOB_ACTION_DELETE,
+          filePath: '/src/delete/me',
+          previousPath: '/src/delete/me',
+          content: CONTENT_1,
+        },
+      },
+      updated: {
+        id: 'blob_3',
+        origContent: CONTENT_1,
+        diff: {
+          action: SNIPPET_BLOB_ACTION_UPDATE,
+          filePath: '/lorem.md',
+          previousPath: '/lorem.md',
+          content: CONTENT_2,
+        },
+      },
+      renamed: {
+        id: 'blob_4',
+        diff: {
+          action: SNIPPET_BLOB_ACTION_MOVE,
+          filePath: '/dolar.md',
+          previousPath: '/ipsum.md',
+          content: CONTENT_1,
+        },
+      },
+      renamedAndUpdated: {
+        id: 'blob_5',
+        origContent: CONTENT_1,
+        diff: {
+          action: SNIPPET_BLOB_ACTION_MOVE,
+          filePath: '/sit.md',
+          previousPath: '/sit/amit.md',
+          content: CONTENT_2,
+        },
+      },
+    };
+    const createBlobsFromTestEntries = (entries, isOrig = false) =>
+      entries.reduce(
+        (acc, { id, diff, origContent }) =>
+          Object.assign(acc, {
+            [id]: {
+              id,
+              content: isOrig && origContent ? origContent : diff.content,
+              path: isOrig ? diff.previousPath : diff.filePath,
+            },
+          }),
+        {},
+      );
+
+    it('should create diff from original files', () => {
+      const origBlobs = createBlobsFromTestEntries(
+        [
+          testEntries.deleted,
+          testEntries.updated,
+          testEntries.renamed,
+          testEntries.renamedAndUpdated,
+        ],
+        true,
+      );
+      const blobs = createBlobsFromTestEntries([
+        testEntries.created,
+        testEntries.updated,
+        testEntries.renamed,
+        testEntries.renamedAndUpdated,
+      ]);
+
+      expect(diffAll(blobs, origBlobs)).toEqual([
+        testEntries.deleted.diff,
+        testEntries.created.diff,
+        testEntries.updated.diff,
+        testEntries.renamed.diff,
+        testEntries.renamedAndUpdated.diff,
+      ]);
+    });
+  });
+});