Add error message for unsupported options in watch mode

Author: rafgraph

src/__tests__/configureRollpkg.test.ts

@@ -47,7 +47,41 @@ describe('fails with incorrect configuration', () => {
         cwd: '/',
       }),
     ).rejects.toThrowErrorMatchingInlineSnapshot(
-      `"rollpkg requires a \\"build\\" or \\"watch\\" command with no arguments, received: \\"\\""`,
+      `"rollpkg requires a \\"build\\" or \\"watch\\" command, received: \\"\\""`,
+    );
+  });
+
+  test('fails with "watch" command and "--addUmdBuild" options', async () => {
+    mockFs({
+      '/package.json': JSON.stringify(createTestPackageJson()),
+      '/tsconfig.json': '',
+      '/src/index.ts': '',
+    });
+
+    await expect(
+      checkInvariantsAndGetConfiguration({
+        args: ['watch', '--addUmdBuild'],
+        cwd: '/',
+      }),
+    ).rejects.toThrowErrorMatchingInlineSnapshot(
+      `"--addUmdBuild option is not valid in watch mode (only the esm build is created in watch mode)"`,
+    );
+  });
+
+  test('fails with "watch" command and "--noStats" options', async () => {
+    mockFs({
+      '/package.json': JSON.stringify(createTestPackageJson()),
+      '/tsconfig.json': '',
+      '/src/index.ts': '',
+    });
+
+    await expect(
+      checkInvariantsAndGetConfiguration({
+        args: ['watch', '--noStats'],
+        cwd: '/',
+      }),
+    ).rejects.toThrowErrorMatchingInlineSnapshot(
+      `"--noStats option is not valid in watch mode (stats are never calculated in watch mode)"`,
     );
   });
 

src/configureRollpkg.ts

@@ -31,7 +31,7 @@ export const checkInvariantsAndGetConfiguration: ConfigureRollpkg = async ({
 }) => {
   invariant(
     args[0] === 'build' || args[0] === 'watch',
-    `rollpkg requires a "build" or "watch" command with no arguments, received: "${args.join(
+    `rollpkg requires a "build" or "watch" command, received: "${args.join(
       ' ',
     )}"`,
   );
@@ -50,7 +50,16 @@ export const checkInvariantsAndGetConfiguration: ConfigureRollpkg = async ({
   }
 
   const addUmdBuild = args.includes('--addUmdBuild');
+  invariant(
+    !watchMode || (watchMode && !addUmdBuild),
+    '--addUmdBuild option is not valid in watch mode (only the esm build is created in watch mode)',
+  );
+
   const includeBundlephobiaStats = !args.includes('--noStats');
+  invariant(
+    !watchMode || (watchMode && includeBundlephobiaStats),
+    '--noStats option is not valid in watch mode (stats are never calculated in watch mode)',
+  );
 
   interface PkgJson extends PackageJson {
     umdGlobalDependencies?: { [key: string]: string };