Add first class Javascript/Typescript support to the Mill build tool (#…

…4135)

#3927

### Checklist
- [x] **example/jslib/testing/1-test-suite**
    - [x]         vite
    - [x]         Jasmine

example/javascriptlib/testing/1-test-suite/baz/src/calculator.js

@@ -0,0 +1,11 @@
+export class Calculator {
+    add(a, b) {
+        return a + b;
+    }
+    divide(a, b) {
+        if (b === 0) {
+            throw new Error("Division by zero is not allowed");
+        }
+        return a / b;
+    }
+}

example/javascriptlib/testing/1-test-suite/baz/src/calculator.ts

@@ -0,0 +1,12 @@
+export class Calculator {
+    add(a: number, b: number): number {
+        return a + b;
+    }
+
+    divide(a: number, b: number): number {
+        if (b === 0) {
+            throw new Error("Division by zero is not allowed");
+        }
+        return a / b;
+    }
+}

example/javascriptlib/testing/1-test-suite/baz/test/src/baz/calculator.test.js

@@ -0,0 +1,24 @@
+import { describe, it, expect } from 'vitest';
+import { Calculator } from 'baz/calculator';
+describe('Calculator', () => {
+    const calculator = new Calculator();
+    describe('Addition', () => {
+        test('should return the sum of two numbers', () => {
+            const result = calculator.add(2, 3);
+            expect(result).toEqual(5);
+        });
+        test('should return the correct sum for negative numbers', () => {
+            const result = calculator.add(-2, -3);
+            expect(result).toEqual(-5);
+        });
+    });
+    describe('Division', () => {
+        test('should return the quotient of two numbers', () => {
+            const result = calculator.divide(6, 3);
+            expect(result).toEqual(2);
+        });
+        it('should throw an error when dividing by zero', () => {
+            expect(() => calculator.divide(6, 0)).toThrow("Division by zero is not allowed");
+        });
+    });
+});

example/javascriptlib/testing/1-test-suite/baz/test/src/baz/calculator.test.ts

@@ -0,0 +1,28 @@
+import { Calculator } from 'baz/calculator';
+
+describe('Calculator', () => {
+    const calculator = new Calculator();
+
+    describe('Addition', () => {
+        test('should return the sum of two numbers', () => {
+            const result = calculator.add(2, 3);
+            expect(result).toEqual(5);
+        });
+
+        test('should return the correct sum for negative numbers', () => {
+            const result = calculator.add(-2, -3);
+            expect(result).toEqual(-5);
+        });
+    });
+
+    describe('Division', () => {
+        test('should return the quotient of two numbers', () => {
+            const result = calculator.divide(6, 3);
+            expect(result).toEqual(2);
+        });
+
+        it('should throw an error when dividing by zero', () => {
+            expect(() => calculator.divide(6, 0)).toThrow("Division by zero is not allowed");
+        });
+    });
+});

example/javascriptlib/testing/1-test-suite/build.mill

@@ -6,10 +6,18 @@ object bar extends TypeScriptModule {
   object test extends TypeScriptTests with TestModule.Jest
 }
 
+object baz extends TypeScriptModule {
+  object test extends TypeScriptTests with TestModule.Vitest
+}
+
 object foo extends TypeScriptModule {
   object test extends TypeScriptTests with TestModule.Mocha
 }
 
+object qux extends TypeScriptModule {
+  object test extends TypeScriptTests with TestModule.Jasmine
+}
+
 // Documentation for mill.example.javascriptlib
 // This build defines two modules bar and foo with test suites configured to use
 // Mocha & Jest resepectively.
@@ -27,4 +35,14 @@ object foo extends TypeScriptModule {
 Test Suites:...1 passed, 1 total...
 Tests:...4 passed, 4 total...
 ...
+
+> mill baz.test
+.../calculator.test.ts...
+...Test Files  1 passed...
+...Tests  4 passed...
+...
+
+> mill qux.test
+...
+4 specs, 0 failures
 */

example/javascriptlib/testing/1-test-suite/qux/src/calculator.js

@@ -0,0 +1,11 @@
+export class Calculator {
+    add(a, b) {
+        return a + b;
+    }
+    divide(a, b) {
+        if (b === 0) {
+            throw new Error("Division by zero is not allowed");
+        }
+        return a / b;
+    }
+}

example/javascriptlib/testing/1-test-suite/qux/src/calculator.ts

@@ -0,0 +1,12 @@
+export class Calculator {
+    add(a: number, b: number): number {
+        return a + b;
+    }
+
+    divide(a: number, b: number): number {
+        if (b === 0) {
+            throw new Error("Division by zero is not allowed");
+        }
+        return a / b;
+    }
+}

example/javascriptlib/testing/1-test-suite/qux/test/src/calculator.test.ts

@@ -0,0 +1,28 @@
+import { Calculator } from 'qux/calculator';
+
+describe('Calculator', () => {
+    const calculator = new Calculator();
+
+    describe('Addition', () => {
+        it('should return the sum of two numbers', () => {
+            const result = calculator.add(2, 3);
+            expect(result).toEqual(5);
+        });
+
+        it('should return the correct sum for negative numbers', () => {
+            const result = calculator.add(-2, -3);
+            expect(result).toEqual(-5);
+        });
+    });
+
+    describe('Division', () => {
+        it('should return the quotient of two numbers', () => {
+            const result = calculator.divide(6, 3);
+            expect(result).toEqual(2);
+        });
+
+        it('should throw an error when dividing by zero', () => {
+            expect(() => calculator.divide(6, 0)).toThrowError("Division by zero is not allowed");
+        });
+    });
+});

example/javascriptlib/testing/1-test-suite/vite.config.ts

@@ -0,0 +1,12 @@
+/// <reference types="vitest" />
+import { defineConfig } from 'vite';
+import tsconfigPaths from 'vite-tsconfig-paths';
+
+export default defineConfig({
+    plugins: [tsconfigPaths()],
+    test: {
+        globals: true,
+        environment: 'node',
+        include: ['**/**/*.test.ts']
+    },
+});

javascriptlib/src/mill/javascriptlib/TestModule.scala

@@ -56,10 +56,6 @@ object TestModule {
     def testConfigSource: T[PathRef] =
       Task.Source(Task.workspace / "jest.config.ts")
 
-    override def allSources: T[IndexedSeq[PathRef]] = Task {
-      super.allSources() ++ IndexedSeq(testConfigSource())
-    }
-
     override def compilerOptions: T[Map[String, ujson.Value]] =
       Task { super.compilerOptions() + ("resolveJsonModule" -> ujson.Bool(true)) }
 
@@ -144,4 +140,129 @@ object TestModule {
     }
 
   }
+
+  trait Vitest extends TypeScriptModule with Shared with TestModule {
+    override def npmDevDeps: T[Seq[String]] =
+      Task {
+        Seq(
+          "@vitest/runner@2.1.8",
+          "vite@5.4.11",
+          "vite-tsconfig-paths@3.6.0",
+          "vitest@2.1.8"
+        )
+      }
+
+    def testConfigSource: T[PathRef] =
+      Task.Source(Task.workspace / "vite.config.ts")
+
+    override def compilerOptions: T[Map[String, ujson.Value]] =
+      Task {
+        super.compilerOptions() + (
+          "target" -> ujson.Str("ESNext"),
+          "module" -> ujson.Str("ESNext"),
+          "moduleResolution" -> ujson.Str("Node"),
+          "skipLibCheck" -> ujson.Bool(true),
+          "types" -> ujson.Arr(
+            s"${npmInstall().path}/node_modules/vitest/globals"
+          )
+        )
+      }
+
+    def getConfigFile: T[String] =
+      Task { (compile()._1.path / "vite.config.ts").toString }
+
+    private def copyConfig: Task[Unit] = Task.Anon {
+      os.copy.over(
+        testConfigSource().path,
+        compile()._1.path / "vite.config.ts"
+      )
+    }
+
+    private def runTest: T[TestResult] = Task {
+      copyConfig()
+      os.call(
+        (
+          "node",
+          npmInstall().path / "node_modules/.bin/vitest",
+          "--run",
+          "--config",
+          getConfigFile(),
+          getPathToTest()
+        ),
+        stdout = os.Inherit,
+        env = mkENV(),
+        cwd = compile()._1.path
+      )
+      ()
+    }
+
+    protected def testTask(args: Task[Seq[String]]): Task[TestResult] = Task.Anon {
+      runTest()
+    }
+
+  }
+
+  trait Jasmine extends TypeScriptModule with Shared with TestModule {
+    override def npmDevDeps: T[Seq[String]] =
+      Task {
+        Seq(
+          "@types/jasmine@5.1.2",
+          "jasmine@5.1.0",
+          "ts-node@10.9.1",
+          "tsconfig-paths@4.2.0",
+          "typescript@5.2.2"
+        )
+      }
+
+    override def compilerOptions: T[Map[String, ujson.Value]] =
+      Task {
+        super.compilerOptions() + (
+          "target" -> ujson.Str("ES5"),
+          "module" -> ujson.Str("commonjs"),
+          "moduleResolution" -> ujson.Str("node"),
+          "allowJs" -> ujson.Bool(true)
+        )
+      }
+
+    def configBuilder: T[PathRef] = Task {
+      val path = compile()._1.path / "jasmine.json"
+      os.write(
+        path,
+        ujson.write(
+          ujson.Obj(
+            "spec_dir" -> ujson.Str("typescript/src"),
+            "spec_files" -> ujson.Arr(ujson.Str("**/*.test.ts")),
+            "stopSpecOnExpectationFailure" -> ujson.Bool(false),
+            "random" -> ujson.Bool(false)
+          )
+        )
+      )
+      PathRef(path)
+    }
+
+    private def runTest: T[Unit] = Task {
+      configBuilder()
+      val jasmine = npmInstall().path / "node_modules/jasmine/bin/jasmine.js"
+      val tsnode = npmInstall().path / "node_modules/ts-node/register/transpile-only.js"
+      val tsconfigPath = npmInstall().path / "node_modules/tsconfig-paths/register.js"
+      os.call(
+        (
+          "node",
+          jasmine,
+          "--config=jasmine.json",
+          s"--require=$tsnode",
+          s"--require=$tsconfigPath"
+        ),
+        stdout = os.Inherit,
+        env = mkENV(),
+        cwd = compile()._1.path
+      )
+      ()
+    }
+
+    protected def testTask(args: Task[Seq[String]]): Task[TestResult] = Task.Anon {
+      runTest()
+    }
+
+  }
 }

javascriptlib/src/mill/javascriptlib/TypeScriptModule.scala

@@ -19,13 +19,13 @@ trait TypeScriptModule extends Module { outer =>
     Task.traverse(moduleDeps)(_.npmDevDeps)().flatten ++ npmDevDeps()
   }
 
-  def npmInstall: Target[PathRef] = Task {
+  def npmInstall: T[PathRef] = Task {
     os.call((
       "npm",
       "install",
       "--save-dev",
-      "@types/node@22.7.8",
-      "typescript@5.6.3",
+      "@types/node@22.10.2",
+      "typescript@5.7.2",
       "ts-node@^10.9.2",
       "esbuild@0.24.0",
       "@esbuild-plugins/tsconfig-paths@0.1.2",
@@ -36,13 +36,13 @@ trait TypeScriptModule extends Module { outer =>
     PathRef(Task.dest)
   }
 
-  def sources: Target[PathRef] = Task.Source(millSourcePath / "src")
+  def sources: T[PathRef] = Task.Source(millSourcePath / "src")
 
-  def allSources: Target[IndexedSeq[PathRef]] =
+  def allSources: T[IndexedSeq[PathRef]] =
     Task { os.walk(sources().path).filter(_.ext == "ts").map(PathRef(_)) }
 
   // specify tsconfig.compilerOptions
-  def compilerOptions: Task[Map[String, ujson.Value]] = Task {
+  def compilerOptions: Task[Map[String, ujson.Value]] = Task.Anon {
     Map(
       "esModuleInterop" -> ujson.Bool(true),
       "declaration" -> ujson.Bool(true),
@@ -89,15 +89,15 @@ trait TypeScriptModule extends Module { outer =>
       )
     )
 
-    os.call(npmInstall().path / "node_modules/typescript/bin/tsc")
+    os.call(npmInstall().path / "node_modules/.bin/tsc")
     os.copy.over(millSourcePath, Task.dest / "typescript")
 
     (PathRef(Task.dest), PathRef(Task.dest / "typescript"))
   }
 
-  def mainFileName: Target[String] = Task { s"${millSourcePath.last}.ts" }
+  def mainFileName: T[String] = Task { s"${millSourcePath.last}.ts" }
 
-  def mainFilePath: Target[Path] = Task { compile()._2.path / "src" / mainFileName() }
+  def mainFilePath: T[Path] = Task { compile()._2.path / "src" / mainFileName() }
 
   def mkENV: T[Map[String, String]] =
     Task {
@@ -158,7 +158,7 @@ trait TypeScriptModule extends Module { outer =>
 
   }
 
-  def bundle: Target[PathRef] = Task {
+  def bundle: T[PathRef] = Task {
     val env = mkENV()
     val tsnode = npmInstall().path / "node_modules/.bin/ts-node"
     val bundleScript = compile()._1.path / "build.ts"