fix(babel): instrumentation was done twice when using babel

Closes kulshekhar#713

e2e/__cases__/simple/Hello.ts

@@ -1,3 +1,7 @@
 export class Hello {
   constructor(readonly msg: string) {}
+
+  get upper() {
+    return this.msg.toUpperCase()
+  }
 }

e2e/__tests__/__snapshots__/coverage.test.ts.snap

@@ -0,0 +1,116 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`using template "default" should report coverages 1`] = `
+  √ jest --coverage
+  ↳ exit code: 0
+  ===[ STDOUT ]===================================================================
+  ----------|----------|----------|----------|----------|-------------------|
+  File      |  % Stmts | % Branch |  % Funcs |  % Lines | Uncovered Line #s |
+  ----------|----------|----------|----------|----------|-------------------|
+  All files |    83.33 |      100 |    66.67 |       80 |                   |
+   Hello.ts |    83.33 |      100 |    66.67 |       80 |                 5 |
+  ----------|----------|----------|----------|----------|-------------------|
+  ===[ STDERR ]===================================================================
+  PASS ./Hello.spec.ts
+    Hello Class
+      √ should create a new Hello
+  
+  Test Suites: 1 passed, 1 total
+  Tests:       1 passed, 1 total
+  Snapshots:   0 total
+  Time:        XXs
+  Ran all test suites.
+  ================================================================================
+`;
+
+exports[`using template "with-babel-6" should report coverages 1`] = `
+  √ jest --coverage
+  ↳ exit code: 0
+  ===[ STDOUT ]===================================================================
+  ----------|----------|----------|----------|----------|-------------------|
+  File      |  % Stmts | % Branch |  % Funcs |  % Lines | Uncovered Line #s |
+  ----------|----------|----------|----------|----------|-------------------|
+  All files |    83.33 |      100 |    66.67 |       80 |                   |
+   Hello.ts |    83.33 |      100 |    66.67 |       80 |                 5 |
+  ----------|----------|----------|----------|----------|-------------------|
+  ===[ STDERR ]===================================================================
+  PASS ./Hello.spec.ts
+    Hello Class
+      √ should create a new Hello
+  
+  Test Suites: 1 passed, 1 total
+  Tests:       1 passed, 1 total
+  Snapshots:   0 total
+  Time:        XXs
+  Ran all test suites.
+  ================================================================================
+`;
+
+exports[`using template "with-babel-7" should report coverages 1`] = `
+  √ jest --coverage
+  ↳ exit code: 0
+  ===[ STDOUT ]===================================================================
+  ----------|----------|----------|----------|----------|-------------------|
+  File      |  % Stmts | % Branch |  % Funcs |  % Lines | Uncovered Line #s |
+  ----------|----------|----------|----------|----------|-------------------|
+  All files |    83.33 |      100 |    66.67 |       80 |                   |
+   Hello.ts |    83.33 |      100 |    66.67 |       80 |                 5 |
+  ----------|----------|----------|----------|----------|-------------------|
+  ===[ STDERR ]===================================================================
+  PASS ./Hello.spec.ts
+    Hello Class
+      √ should create a new Hello
+  
+  Test Suites: 1 passed, 1 total
+  Tests:       1 passed, 1 total
+  Snapshots:   0 total
+  Time:        XXs
+  Ran all test suites.
+  ================================================================================
+`;
+
+exports[`using template "with-jest-22" should report coverages 1`] = `
+  √ jest --coverage
+  ↳ exit code: 0
+  ===[ STDOUT ]===================================================================
+  ----------|----------|----------|----------|----------|-------------------|
+  File      |  % Stmts | % Branch |  % Funcs |  % Lines | Uncovered Line #s |
+  ----------|----------|----------|----------|----------|-------------------|
+  All files |    83.33 |      100 |    66.67 |       80 |                   |
+   Hello.ts |    83.33 |      100 |    66.67 |       80 |                 5 |
+  ----------|----------|----------|----------|----------|-------------------|
+  ===[ STDERR ]===================================================================
+  PASS ./Hello.spec.ts
+    Hello Class
+      √ should create a new Hello
+  
+  Test Suites: 1 passed, 1 total
+  Tests:       1 passed, 1 total
+  Snapshots:   0 total
+  Time:        XXs
+  Ran all test suites.
+  ================================================================================
+`;
+
+exports[`using template "with-typescript-2-7" should report coverages 1`] = `
+  √ jest --coverage
+  ↳ exit code: 0
+  ===[ STDOUT ]===================================================================
+  ----------|----------|----------|----------|----------|-------------------|
+  File      |  % Stmts | % Branch |  % Funcs |  % Lines | Uncovered Line #s |
+  ----------|----------|----------|----------|----------|-------------------|
+  All files |    83.33 |      100 |    66.67 |       80 |                   |
+   Hello.ts |    83.33 |      100 |    66.67 |       80 |                 5 |
+  ----------|----------|----------|----------|----------|-------------------|
+  ===[ STDERR ]===================================================================
+  PASS ./Hello.spec.ts
+    Hello Class
+      √ should create a new Hello
+  
+  Test Suites: 1 passed, 1 total
+  Tests:       1 passed, 1 total
+  Snapshots:   0 total
+  Time:        XXs
+  Ran all test suites.
+  ================================================================================
+`;

e2e/__tests__/coverage.test.ts

@@ -0,0 +1,17 @@
+import { allValidPackageSets } from '../__helpers__/templates'
+import { configureTestCase } from '../__helpers__/test-case'
+
+const testCase = configureTestCase('simple', {
+  args: ['--coverage'],
+})
+
+testCase.runWithTemplates(allValidPackageSets, 0, (runTest, { templateName }) => {
+  describe(`using template "${templateName}"`, () => {
+    const result = runTest()
+
+    it(`should report coverages`, () => {
+      expect(result.status).toBe(0)
+      expect(result).toMatchSnapshot()
+    })
+  })
+})

src/ts-jest-transformer.spec.ts

@@ -31,6 +31,7 @@ describe('lastTransformerId', () => {
 describe('process', () => {
   let tr: TsJestTransformer
   let babel: any
+  let args: [string, string, any, any]
   const config = {
     shouldStringifyContent: jest.fn(),
     get babelJestTransformer() {
@@ -42,9 +43,11 @@ describe('process', () => {
   const INPUT = 'export default "foo"'
   const FILE = '/foo/bar.ts'
   const JEST_CONFIG = {} as jest.ProjectConfig
-  const process = () => tr.process(INPUT, FILE, JEST_CONFIG)
+  const OPTIONS = { instrument: false }
+  const process = () => tr.process(...args)
   beforeEach(() => {
     tr = new TsJestTransformer()
+    args = [INPUT, FILE, JEST_CONFIG, OPTIONS]
     jest
       .spyOn(tr, 'configsFor')
       .mockImplementation(() => config)
@@ -89,7 +92,9 @@ Array [
     "ts:export default \\"foo\\"",
     "/foo/bar.ts",
     Object {},
-    undefined,
+    Object {
+      "instrument": false,
+    },
   ],
 ]
 `)
@@ -100,6 +105,23 @@ Array [
     "/foo/bar.ts",
   ],
 ]
+`)
+  })
+
+  it('should not pass the instrument option to babel-jest', () => {
+    args[3] = { instrument: true }
+    expect(process()).toBe(`babel:ts:${INPUT}`)
+    expect(config.babelJestTransformer.process.mock.calls).toMatchInlineSnapshot(`
+Array [
+  Array [
+    "ts:export default \\"foo\\"",
+    "/foo/bar.ts",
+    Object {},
+    Object {
+      "instrument": false,
+    },
+  ],
+]
 `)
   })
 })

src/ts-jest-transformer.ts

@@ -109,7 +109,8 @@ export class TsJestTransformer implements jest.Transformer {
     // calling babel-jest transformer
     if (babelJest) {
       this.logger.debug({ fileName: filePath }, 'calling babel-jest processor')
-      result = babelJest.process(result, filePath, jestConfig, transformOptions)
+      // do not instrument here, jest will do it anyway afterwards
+      result = babelJest.process(result, filePath, jestConfig, { ...transformOptions, instrument: false })
     }
 
     // allows hooks (useful for testing)