added integration tests

Author: Cyrik

src/NotebookProvider.ts

@@ -92,7 +92,9 @@ function parseClojure(content: string): vscode.NotebookCellData[] {
         });
       }
 
-      _.last(commentCells).metadata.trailing = content.substring(previouseEnd, end);
+      if (commentCells.length) {
+        _.last(commentCells).metadata.trailing = content.substring(previouseEnd, end);
+      }
 
       return commentCells;
     }

src/extension-test/integration/suite/serialization-test.ts

@@ -0,0 +1,59 @@
+import assert = require('assert');
+import * as fsPromises from 'fs/promises';
+import path = require('path');
+import * as testUtil from './util';
+import { NotebookProvider } from '../../../NotebookProvider';
+import { before, after } from 'mocha';
+import { serialize } from 'v8';
+import _ = require('lodash');
+
+const tester = new NotebookProvider();
+const suiteName = 'notebook';
+const decoder = new TextDecoder();
+
+const ignoreList = ['highlight_test.clj'];
+
+async function absoluteFileNamesIn(directoryName, results: string[] = []) {
+  const files = await fsPromises.readdir(directoryName, { withFileTypes: true });
+  for (const f of files) {
+    const fullPath = path.join(directoryName, f.name);
+    if (f.isDirectory()) {
+      await absoluteFileNamesIn(fullPath, results);
+    } else {
+      results.push(fullPath);
+    }
+  }
+  return results;
+}
+
+suite('serialization', () => {
+  before(() => {
+    testUtil.showMessage(suiteName, `suite starting!`);
+  });
+
+  after(() => {
+    testUtil.showMessage(suiteName, `suite done!`);
+  });
+
+  test('input equals output', async () => {
+    const testFilePath = path.join(testUtil.testDataDir, '..');
+
+    const fileNames = await absoluteFileNamesIn(testFilePath);
+
+    const contents = await Promise.all(
+      fileNames
+        .filter(
+          (x) =>
+            '.clj' === path.parse(x).ext && _.some(ignoreList, (toIgnore) => !x.endsWith(toIgnore))
+        )
+        .map((name) => fsPromises.readFile(name))
+    );
+
+    for (const fileBuffer of contents) {
+      const notebook = await tester.deserializeNotebook(fileBuffer, null);
+      const serializedNotebook = await tester.serializeNotebook(notebook, null);
+
+      assert.equal(decoder.decode(serializedNotebook), decoder.decode(fileBuffer));
+    }
+  });
+});