Feature: add typescript-support/warn

- uses console.warn() instead of throwing an error
- useful for development time, when you don't want everything to stop because you have unused variable

packages/typescript-support/package.json

@@ -13,7 +13,6 @@
     "prepack": "yarn build"
   },
   "dependencies": {
-    "chalk": "^2.4.1",
     "node-typescript-service": "^0.4.0",
     "source-map-support": "^0.5.6"
   },
@@ -22,7 +21,8 @@
   },
   "files": [
     "cjs",
-    "src"
+    "src",
+    "warn.js"
   ],
   "author": "Avi Vahl <avi.vahl@wix.com>",
   "license": "MIT",

packages/typescript-support/src/register-warn.ts

@@ -0,0 +1,6 @@
+import { registerNodeExtension, formatDiagnostics } from './register-node-extension'
+
+registerNodeExtension(diagnostics => {
+    // tslint:disable-next-line:no-console
+    console.warn(formatDiagnostics(diagnostics))
+})

packages/typescript-support/test/register-throw.unit.ts

@@ -34,7 +34,7 @@ describe('using node -r typescript-support [file]', () => {
             expect(output).to.include(`at runMe (${fileThatThrows}:11:15)`)
         })
 
-        it('isolates two folders with different configs', () => {
+        it('isolates two folders with different configs and throws errors', () => {
             const workingFile = join(fixturesDirectory, 'type-isolation', 'with-tsconfig-b', 'passes-type-check.ts')
 
             const { output, exitCode } = runCommand(`node -r typescript-support ${workingFile}`)

packages/typescript-support/test/register-warn.unit.ts

@@ -0,0 +1,69 @@
+import { expect } from 'chai'
+import { join, dirname } from 'path'
+import { platform } from 'os'
+import { runCommand } from './run-command'
+
+const fixturesDirectory = dirname(require.resolve('test-fixtures/package.json'))
+
+describe('using node -r typescript-support/warn [file]', () => {
+    describe('with tsconfig.json', () => {
+        it('prints syntactic errors', () => {
+            const fileWithSyntaxError = join(fixturesDirectory, 'errors', 'file-with-syntax-error.ts')
+
+            const { output, exitCode } = runCommand(`node -r typescript-support/warn ${fileWithSyntaxError}`)
+
+            expect(exitCode).to.equal(0)
+            expect(output).to.include(`')' expected`)
+        })
+
+        it('prints semantic errors', () => {
+            const fileWithTypeError = join(fixturesDirectory, 'errors', 'file-with-type-error.ts')
+
+            const { output, exitCode } = runCommand(`node -r typescript-support/warn ${fileWithTypeError}`)
+
+            expect(exitCode).to.equal(0)
+            expect(output).to.include(`Type '123' is not assignable to type 'string'`)
+        })
+
+        it('maps stack traces using source maps', () => {
+            const fileThatThrows = join(fixturesDirectory, 'source-maps', 'with-tsconfig', 'throwing.ts')
+
+            const { output, exitCode } = runCommand(`node -r typescript-support/warn ${fileThatThrows}`)
+
+            expect(exitCode).to.not.equal(0)
+            expect(output).to.include(`at runMe (${fileThatThrows}:11:15)`)
+        })
+
+        it('isolates two folders with different configs and prints errors', () => {
+            const workingFile = join(fixturesDirectory, 'type-isolation', 'with-tsconfig-b', 'passes-type-check.ts')
+
+            const { output, exitCode } = runCommand(`node -r typescript-support/warn ${workingFile}`)
+
+            expect(exitCode).to.equal(0)
+            expect(output).to.include(`Cannot find name 'describe'`)
+            expect(output).to.include('should-error.ts')
+        })
+
+    })
+
+    describe('no tsconfig.json', () => {
+        it('maps stack traces using source maps', () => {
+            const fileThatThrows = join(fixturesDirectory, 'source-maps', 'throwing-without-tsconfig.ts')
+
+            const { output, exitCode } = runCommand(`node -r typescript-support/warn ${fileThatThrows}`)
+
+            expect(exitCode).to.not.equal(0)
+            expect(output).to.include(`at runMe (${fileThatThrows}:9:11)`)
+        })
+
+        it('allows using imports', () => {
+            const fileWithImports = join(fixturesDirectory, 'no-tsconfig', 'imports.ts')
+
+            const { output, exitCode } = runCommand(`node -r typescript-support/warn ${fileWithImports}`)
+
+            expect(exitCode).to.equal(0)
+            expect(output).to.include(`Current platform is: ${platform()}`)
+        })
+    })
+
+})

packages/typescript-support/warn.js

@@ -0,0 +1 @@
+require('./cjs/register-warn')