(test): ensure --extractErrors kind of works

- the test output strips away `invariant` entirely in all builds,
  instead of replacing it with ErrorProd/ErrorDev etc...
  - it leaves an empty import however...
    - which gives an unused import warning during builds
  - and it doesn't do anything with `warning` at all, it doesn't get
    stripped or changed, and it's message is not in codes.json
    - the source code indeed only checks for 'invariant'
  - and it does generate errors/codes.json, ErrorProd.js, ErrorDev.js
  - I'm not 100% sure, but that seems to be buggy to me

(refactor): split --extractError code into a build-options fixture
- as it doesn't require tsdx.config.js at all
- but it is an integration test, as it requires tiny-invariant etc

(clean): remove the errors/ directory as that's auto-generated by
--extractErrors and is the thing being tested

(clean): remove src/foo.ts as it's extraneous

test/integration-tests/fixtures/README.md

@@ -1,3 +1,4 @@
 # Integration Test Fixtures Directory
 
+- `build-options` lets us check that TSDX's flags work as expected
 - `build-withConfig` lets us check that `tsdx.config.js` works as expected

test/integration-tests/fixtures/build-options/package.json

@@ -0,0 +1,7 @@
+{
+  "scripts": {
+    "build": "tsdx build --extractErrors"
+  },
+  "name": "build-options",
+  "license": "MIT"
+}

test/integration-tests/fixtures/build-options/src/index.ts

@@ -0,0 +1,12 @@
+import invariant from 'tiny-invariant';
+import warning from 'tiny-warning';
+
+invariant(true, 'error occurred! o no');
+warning(true, 'warning - water is wet');
+
+export const sum = (a: number, b: number) => {
+  if ('development' === process.env.NODE_ENV) {
+    console.log('fuck');
+  }
+  return a + b;
+};

test/integration-tests/fixtures/build-options/tsconfig.json

@@ -0,0 +1,28 @@
+{
+  "compilerOptions": {
+    "module": "ESNext",
+    "lib": ["dom", "esnext"],
+    "declaration": true,
+    "sourceMap": true,
+    "rootDir": "./src",
+    "strict": true,
+    "noImplicitAny": true,
+    "strictNullChecks": true,
+    "strictFunctionTypes": true,
+    "strictPropertyInitialization": true,
+    "noImplicitThis": true,
+    "alwaysStrict": true,
+    "noUnusedLocals": true,
+    "noUnusedParameters": true,
+    "noImplicitReturns": true,
+    "noFallthroughCasesInSwitch": true,
+    "moduleResolution": "node",
+    "baseUrl": "./",
+    "paths": {
+      "*": ["src/*", "node_modules/*"]
+    },
+    "jsx": "react",
+    "esModuleInterop": true
+  },
+  "include": ["src", "types"],
+}

test/integration-tests/fixtures/build-withConfig/package.json

@@ -1,6 +1,6 @@
 {
   "scripts": {
-    "build": "tsdx build --extractErrors"
+    "build": "tsdx build"
   },
   "name": "build-withconfig",
   "license": "MIT"

test/integration-tests/fixtures/build-withConfig/src/index.ts

@@ -1,9 +1,3 @@
-import invariant from 'tiny-invariant';
-import warning from 'tiny-warning';
-invariant(true, 'error occurred! o no');
-warning(false, 'warning - water is wet');
-export { foo } from './foo';
-
 export const sum = (a: number, b: number) => {
   if ('development' === process.env.NODE_ENV) {
     console.log('fuck');

test/integration-tests/tsdx-build-options.test.js

@@ -0,0 +1,59 @@
+const shell = require('shelljs');
+
+const util = require('../utils/fixture');
+const { execWithCache } = require('../utils/shell');
+
+shell.config.silent = false;
+
+const testDir = 'integration-tests';
+const fixtureName = 'build-options';
+const stageName = `stage-integration-${fixtureName}`;
+
+describe('integration :: tsdx build :: options', () => {
+  beforeAll(() => {
+    util.teardownStage(stageName);
+    util.setupStageWithFixture(testDir, stageName, fixtureName);
+  });
+
+  it('should create errors/ dir with --extractErrors', () => {
+    const output = execWithCache('node ../dist/index.js build --extractErrors');
+
+    expect(shell.test('-f', 'errors/ErrorDev.js')).toBeTruthy();
+    expect(shell.test('-f', 'errors/ErrorProd.js')).toBeTruthy();
+    expect(shell.test('-f', 'errors/codes.json')).toBeTruthy();
+
+    expect(output.code).toBe(0);
+  });
+
+  it('should have correct errors/codes.json', () => {
+    const output = execWithCache('node ../dist/index.js build --extractErrors');
+
+    const errors = require(`../../${stageName}/errors/codes.json`);
+    expect(errors['0']).toBe('error occurred! o no');
+    // TODO: warning is actually not extracted, only invariant
+    // expect(errors['1']).toBe('warning - water is wet');
+
+    expect(output.code).toBe(0);
+  });
+
+  it('should compile files into a dist directory', () => {
+    const output = execWithCache('node ../dist/index.js build --extractErrors');
+
+    expect(shell.test('-f', 'dist/index.js')).toBeTruthy();
+    expect(
+      shell.test('-f', 'dist/build-options.cjs.development.js')
+    ).toBeTruthy();
+    expect(
+      shell.test('-f', 'dist/build-options.cjs.production.min.js')
+    ).toBeTruthy();
+    expect(shell.test('-f', 'dist/build-options.esm.js')).toBeTruthy();
+
+    expect(shell.test('-f', 'dist/index.d.ts')).toBeTruthy();
+
+    expect(output.code).toBe(0);
+  });
+
+  afterAll(() => {
+    util.teardownStage(stageName);
+  });
+});