feat(config): add incremental option

.eslintrc.js

@@ -7,6 +7,9 @@ module.exports = {
     ecmaVersion: 2020,
     sourceType: 'module',
     impliedStrict: true,
+    ecmaFeatures: {
+      jsx: true,
+    },
   },
   rules: {
     'no-console': ['error', { allow: ['warn', 'error', 'log'] }],

CHANGELOG.md

@@ -1,5 +1,5 @@
 <a name="25.2.1"></a>
-# [25.2.1](https://github.com/kulshekhar/ts-jest/compare/25.2.1...25.2.0) (2020-02-21)
+# [25.2.1](https://github.com/kulshekhar/ts-jest/compare/25.2.0...25.2.1) (2020-02-21)
 
 
 ### Bug Fixes

docs/user/config/compilerHost.md

@@ -0,0 +1,93 @@
+---
+title: Compiler Host option
+---
+
+By default `ts-jest` uses TypeScript `LanguageService` API in the context of a project (yours), with full type-checking and features.
+But TypeScript `Program` can also be used to achieve the same behavior as `LanguageService`.
+That's what the `compilerHost` option (which defaults to `false`) does.
+
+There are 2 types of TypeScript `Program`, one is `Incremental Program` which is only available from TypeScript 3.4 
+and the other one is normal `Program`.
+
+By default `ts-jest` uses `Incremental Program` if `compilerHost` is enabled. The priority of using TypeScript APIs in `ts-jest`
+as below:
+- Default TypeScript API is `LanguageService`.
+- `compilerHost` is enabled:
+    - `incremental` is enabled (**default**): use TypeScript `Incremental Program`.
+    - `incremental` is disabled: use TypeScript `Program`.
+- `isolatedModules` is enabled, use TypeScript transpile modules.
+
+Here is how to enable `ts-jest` to compile using TypeScript `Program`
+
+### Example
+
+<div class="row"><div class="col-md-6" markdown="block">
+
+```js
+// jest.config.js
+module.exports = {
+  // [...]
+  globals: {
+    'ts-jest': {
+      compilerHost: true,
+      incremental: false,
+    }
+  }
+};
+```
+
+</div><div class="col-md-6" markdown="block">
+
+```js
+// OR package.json
+{
+  // [...]
+  "jest": {
+    "globals": {
+      "ts-jest": {
+        "compilerHost": true,
+        "incremental": false
+      }
+    }
+  }
+}
+```
+
+</div></div>
+
+
+Here is how to enable `ts-jest` to compile using TypeScript `IncrementalProgram`
+
+### Example
+
+<div class="row"><div class="col-md-6" markdown="block">
+
+```js
+// jest.config.js
+module.exports = {
+  // [...]
+  globals: {
+    'ts-jest': {
+      compilerHost: true
+    }
+  }
+};
+```
+
+</div><div class="col-md-6" markdown="block">
+
+```js
+// OR package.json
+{
+  // [...]
+  "jest": {
+    "globals": {
+      "ts-jest": {
+        "compilerHost": true
+      }
+    }
+  }
+}
+```
+
+</div></div>

docs/user/config/index.md

@@ -220,6 +220,7 @@ npx ts-jest config:migrate package.json
 [compiler]: compiler
 [tsConfig]: tsConfig
 [isolatedModules]: isolatedModules
+[compilerHost]: compilerHost
 [diagnostics]: diagnostics
 [babelConfig]: babelConfig
 [stringifyContentPathRegex]: stringifyContentPathRegex

e2e/__cases__/compiler-host/main.spec.ts

@@ -0,0 +1,6 @@
+import { g } from './main'
+
+it('should pass', () => {
+  const x: string = g(5)
+  expect(x).toBe(5)
+})

e2e/__cases__/compiler-host/main.ts

@@ -0,0 +1 @@
+export const g = (v: number) => v

e2e/__helpers__/templates.ts

@@ -6,5 +6,7 @@ export enum PackageSets {
   // invalid
   unsupportedVersion = 'with-unsupported-version',
 }
-export const allValidPackageSets = [PackageSets.default, PackageSets.babel7, PackageSets.babel7StringConfig, PackageSets.typescript2_7]
-export const allPackageSetsWithPreset = [PackageSets.default, PackageSets.babel7, PackageSets.babel7StringConfig, PackageSets.typescript2_7]
+export const allValidPackageSets = [PackageSets.default, PackageSets.babel7, PackageSets.babel7StringConfig, PackageSets.typescript2_7],
+  allPackageSetsWithPreset = [PackageSets.default, PackageSets.babel7, PackageSets.babel7StringConfig, PackageSets.typescript2_7],
+  allPackageSetsWithProgram = [PackageSets.default, PackageSets.babel7, PackageSets.babel7StringConfig],
+  allPackageSetsWithoutProgram = [PackageSets.typescript2_7, PackageSets.unsupportedVersion]

e2e/__monorepos__/simple/with-dependency/package.json

@@ -32,7 +32,8 @@
       "ts-jest": {
         "diagnostics": true,
         "tsConfig": "<rootDir>/tsconfig.json",
-        "compilerHost": true
+        "compilerHost": true,
+        "incremental": true
       }
     }
   },

e2e/__monorepos__/simple/with-dependency/tsconfig.json

@@ -13,8 +13,7 @@
     "downlevelIteration": true,
     "strict": true,
     "moduleResolution": "node",
-    "esModuleInterop": true,
-    "incremental": true
+    "esModuleInterop": true
   },
   "include": [
     "./src"

e2e/__tests__/__snapshots__/compiler-host.test.ts.snap

@@ -0,0 +1,219 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`With compilerHost enabled and incremental disabled should fail using template "with-typescript-2-7" 1`] = `
+  × jest --no-cache
+  ↳ exit code: 1
+  ===[ STDOUT ]===================================================================
+
+  ===[ STDERR ]===================================================================
+  FAIL ./main.spec.ts
+    ● Test suite failed to run
+
+      TypeError: Cannot read property 'maxNodeModuleJsDepth' of undefined
+
+        at Object.createProgram (../../__templates__/with-typescript-2-7/node_modules/typescript/lib/typescript.js:73929:51)
+
+  Test Suites: 1 failed, 1 total
+  Tests:       0 total
+  Snapshots:   0 total
+  Time:        XXs
+  Ran all test suites.
+  ================================================================================
+`;
+
+exports[`With compilerHost enabled and incremental disabled should fail using template "with-unsupported-version" 1`] = `
+  × jest --no-cache
+  ↳ exit code: 1
+  ===[ STDOUT ]===================================================================
+
+  ===[ STDERR ]===================================================================
+  ts-jest[versions] (WARN) Version 2.5.3 of typescript installed has not been tested with ts-jest. If you're experiencing issues, consider using a supported version (>=2.7.0 <4.0.0). Please do not report issues in ts-jest if you are using unsupported versions.
+  FAIL ./main.spec.ts
+    ● Test suite failed to run
+
+      TypeError: Cannot read property 'maxNodeModuleJsDepth' of undefined
+
+        at Object.createProgram (../../__templates__/with-unsupported-version/node_modules/typescript/lib/typescript.js:69709:51)
+
+  Test Suites: 1 failed, 1 total
+  Tests:       0 total
+  Snapshots:   0 total
+  Time:        XXs
+  Ran all test suites.
+  ================================================================================
+`;
+
+exports[`With compilerHost enabled and incremental disabled should pass using template "default" 1`] = `
+  √ jest --no-cache
+  ↳ exit code: 0
+  ===[ STDOUT ]===================================================================
+
+  ===[ STDERR ]===================================================================
+  ts-jest[ts-compiler] (WARN) TypeScript diagnostics (customize using \`[jest-config].globals.ts-jest.diagnostics\` option):
+  main.spec.ts:4:9 - error TS2322: Type 'number' is not assignable to type 'string'.
+
+  4   const x: string = g(5)
+            ~
+  PASS ./main.spec.ts
+    √ should pass
+
+  Test Suites: 1 passed, 1 total
+  Tests:       1 passed, 1 total
+  Snapshots:   0 total
+  Time:        XXs
+  Ran all test suites.
+  ================================================================================
+`;
+
+exports[`With compilerHost enabled and incremental disabled should pass using template "with-babel-7" 1`] = `
+  √ jest --no-cache
+  ↳ exit code: 0
+  ===[ STDOUT ]===================================================================
+
+  ===[ STDERR ]===================================================================
+  ts-jest[ts-compiler] (WARN) TypeScript diagnostics (customize using \`[jest-config].globals.ts-jest.diagnostics\` option):
+  main.spec.ts:4:9 - error TS2322: Type 'number' is not assignable to type 'string'.
+
+  4   const x: string = g(5)
+            ~
+  PASS ./main.spec.ts
+    √ should pass
+
+  Test Suites: 1 passed, 1 total
+  Tests:       1 passed, 1 total
+  Snapshots:   0 total
+  Time:        XXs
+  Ran all test suites.
+  ================================================================================
+`;
+
+exports[`With compilerHost enabled and incremental disabled should pass using template "with-babel-7-string-config" 1`] = `
+  √ jest --no-cache
+  ↳ exit code: 0
+  ===[ STDOUT ]===================================================================
+
+  ===[ STDERR ]===================================================================
+  ts-jest[ts-compiler] (WARN) TypeScript diagnostics (customize using \`[jest-config].globals.ts-jest.diagnostics\` option):
+  main.spec.ts:4:9 - error TS2322: Type 'number' is not assignable to type 'string'.
+
+  4   const x: string = g(5)
+            ~
+  PASS ./main.spec.ts
+    √ should pass
+
+  Test Suites: 1 passed, 1 total
+  Tests:       1 passed, 1 total
+  Snapshots:   0 total
+  Time:        XXs
+  Ran all test suites.
+  ================================================================================
+`;
+
+exports[`With compilerHost enabled and incremental enabled should fail using template "with-typescript-2-7" 1`] = `
+  × jest --no-cache
+  ↳ exit code: 1
+  ===[ STDOUT ]===================================================================
+
+  ===[ STDERR ]===================================================================
+  FAIL ./main.spec.ts
+    ● Test suite failed to run
+
+      TypeError: Cannot read property 'maxNodeModuleJsDepth' of undefined
+
+        at Object.createProgram (../../__templates__/with-typescript-2-7/node_modules/typescript/lib/typescript.js:73929:51)
+
+  Test Suites: 1 failed, 1 total
+  Tests:       0 total
+  Snapshots:   0 total
+  Time:        XXs
+  Ran all test suites.
+  ================================================================================
+`;
+
+exports[`With compilerHost enabled and incremental enabled should fail using template "with-unsupported-version" 1`] = `
+  × jest --no-cache
+  ↳ exit code: 1
+  ===[ STDOUT ]===================================================================
+
+  ===[ STDERR ]===================================================================
+  ts-jest[versions] (WARN) Version 2.5.3 of typescript installed has not been tested with ts-jest. If you're experiencing issues, consider using a supported version (>=2.7.0 <4.0.0). Please do not report issues in ts-jest if you are using unsupported versions.
+  FAIL ./main.spec.ts
+    ● Test suite failed to run
+
+      TypeError: Cannot read property 'maxNodeModuleJsDepth' of undefined
+
+        at Object.createProgram (../../__templates__/with-unsupported-version/node_modules/typescript/lib/typescript.js:69709:51)
+
+  Test Suites: 1 failed, 1 total
+  Tests:       0 total
+  Snapshots:   0 total
+  Time:        XXs
+  Ran all test suites.
+  ================================================================================
+`;
+
+exports[`With compilerHost enabled and incremental enabled should pass using template "default" 1`] = `
+  √ jest --no-cache
+  ↳ exit code: 0
+  ===[ STDOUT ]===================================================================
+
+  ===[ STDERR ]===================================================================
+  ts-jest[ts-compiler] (WARN) TypeScript diagnostics (customize using \`[jest-config].globals.ts-jest.diagnostics\` option):
+  main.spec.ts:4:9 - error TS2322: Type 'number' is not assignable to type 'string'.
+
+  4   const x: string = g(5)
+            ~
+  PASS ./main.spec.ts
+    √ should pass
+
+  Test Suites: 1 passed, 1 total
+  Tests:       1 passed, 1 total
+  Snapshots:   0 total
+  Time:        XXs
+  Ran all test suites.
+  ================================================================================
+`;
+
+exports[`With compilerHost enabled and incremental enabled should pass using template "with-babel-7" 1`] = `
+  √ jest --no-cache
+  ↳ exit code: 0
+  ===[ STDOUT ]===================================================================
+
+  ===[ STDERR ]===================================================================
+  ts-jest[ts-compiler] (WARN) TypeScript diagnostics (customize using \`[jest-config].globals.ts-jest.diagnostics\` option):
+  main.spec.ts:4:9 - error TS2322: Type 'number' is not assignable to type 'string'.
+
+  4   const x: string = g(5)
+            ~
+  PASS ./main.spec.ts
+    √ should pass
+
+  Test Suites: 1 passed, 1 total
+  Tests:       1 passed, 1 total
+  Snapshots:   0 total
+  Time:        XXs
+  Ran all test suites.
+  ================================================================================
+`;
+
+exports[`With compilerHost enabled and incremental enabled should pass using template "with-babel-7-string-config" 1`] = `
+  √ jest --no-cache
+  ↳ exit code: 0
+  ===[ STDOUT ]===================================================================
+
+  ===[ STDERR ]===================================================================
+  ts-jest[ts-compiler] (WARN) TypeScript diagnostics (customize using \`[jest-config].globals.ts-jest.diagnostics\` option):
+  main.spec.ts:4:9 - error TS2322: Type 'number' is not assignable to type 'string'.
+
+  4   const x: string = g(5)
+            ~
+  PASS ./main.spec.ts
+    √ should pass
+
+  Test Suites: 1 passed, 1 total
+  Tests:       1 passed, 1 total
+  Snapshots:   0 total
+  Time:        XXs
+  Ran all test suites.
+  ================================================================================
+`;