fix: add stack traces to test message for test error. (#545)

- For thrown error scenarios provides the location of the error thrown inside the tested code with fully navigable trace.
- For non throw error scenarios provides additional context on the failed assertion.

Co-authored-by: ArthurHub <[email protected]>

samples/basic/src/add.ts

@@ -1,7 +1,17 @@
+
 export function add(a: number, b: number) {
   return a + b
 }
 
 export function sum(from: number, to: number) {
   return (from + to) * (to - from + 1) / 2
 }
+
+export function addError(from: number, to: number) {
+  doSomething()
+  return add(from, to)
+}
+
+function doSomething() {
+  throw new Error('Something went wrong');
+}

samples/basic/test/throw.test.ts

@@ -0,0 +1,12 @@
+import { describe, expect, it } from 'vitest';
+import { addError } from '../src/add';
+
+describe('throw error', () => {
+  it('passes expecting an error to be thrown', () => {
+    expect(()=>addError(1, 1)).toThrow()
+  })
+
+  it('fails with error thrown', () => {
+    expect(addError(1, 1)).toBe(2)
+  })
+})

src/runner/runner.ts

@@ -507,6 +507,8 @@ function testMessageForTestError(testItem: vscode.TestItem, error: TestError | u
   else
     testMessage = new vscode.TestMessage(stripVTControlCharacters(error.message) ?? '')
 
+  testMessage.stackTrace = parseMessageStackFramesFromErrorStacks(error.stacks)
+
   const location = parseLocationFromStacks(testItem, error.stacks ?? [])
   if (location) {
     const position = new vscode.Position(location.line - 1, location.column - 1)
@@ -550,6 +552,17 @@ function parseLocationFromStacks(testItem: vscode.TestItem, stacks: ParsedStack[
   log.verbose?.('Could not find a valid stack for', testItem.label, JSON.stringify(stacks, null, 2))
 }
 
+function parseMessageStackFramesFromErrorStacks(stacks: ParsedStack[] | undefined): vscode.TestMessageStackFrame[] | undefined {
+  if (!stacks || stacks.length === 0)
+    return undefined
+
+  return stacks.map((stack) => {
+    const { sourceFilepath, line, column } = getSourceFilepathAndLocationFromStack(stack)
+    const sourceUri = sourceFilepath ? vscode.Uri.file(sourceFilepath) : undefined
+    return new vscode.TestMessageStackFrame(stack.method, sourceUri, new vscode.Position(line - 1, column - 1))
+  })
+}
+
 function getTestFiles(tests: readonly vscode.TestItem[]): string[] | SerializedTestSpecification[] {
   // if there is a folder, we can't limit the tests to a specific project
   const hasFolder = tests.some(test => getTestData(test) instanceof TestFolder)