fix(js): do not override package.json type when defined in tsc executor (#27106)

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## Current Behavior
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Fixes #23579

e2e/js/src/js-packaging.test.ts

@@ -146,10 +146,20 @@ describe('packaging libs', () => {
       json.compilerOptions.module = 'esnext';
       return json;
     });
+    updateJson(`libs/${tscEsmLib}/package.json`, (json) => {
+      // check one lib without type, the build output should be set with type module
+      delete json.type;
+      return json;
+    });
     updateJson(`libs/${swcEsmLib}/.swcrc`, (json) => {
       json.module.type = 'es6';
       return json;
     });
+    updateJson(`libs/${swcEsmLib}/package.json`, (json) => {
+      // check one lib with the type set, the build output should be set with type module
+      json.type = 'module';
+      return json;
+    });
     // Node ESM requires file extensions in imports so must add them before building
     updateFile(
       `libs/${tscEsmLib}/src/index.ts`,

packages/js/src/utils/package-json/update-package-json.spec.ts

@@ -331,6 +331,37 @@ describe('getUpdatedPackageJsonContent', () => {
       },
     });
   });
+
+  it('should no override existing type', () => {
+    // Leave existing type untouched
+    expect(
+      getUpdatedPackageJsonContent(
+        {
+          name: 'test',
+          version: '0.0.1',
+          type: 'module',
+        },
+        {
+          main: 'proj/src/index.ts',
+          outputPath: 'dist/proj',
+          projectRoot: 'proj',
+          format: ['cjs'],
+          outputFileExtensionForCjs: '.cjs',
+          generateExportsField: true,
+        }
+      )
+    ).toEqual({
+      name: 'test',
+      main: './src/index.cjs',
+      types: './src/index.d.ts',
+      version: '0.0.1',
+      type: 'module',
+      exports: {
+        '.': './src/index.cjs',
+        './package.json': './package.json',
+      },
+    });
+  });
 });
 
 describe('updatePackageJson', () => {

packages/js/src/utils/package-json/update-package-json.ts

@@ -96,6 +96,22 @@ export function updatePackageJson(
       : { name: context.projectName, version: '0.0.1' };
   }
 
+  if (packageJson.type === 'module') {
+    if (options.format?.includes('cjs')) {
+      logger.warn(
+        `Package type is set to "module" but "cjs" format is included. Going to use "esm" format instead. You can change the package type to "commonjs" or remove type in the package.json file.`
+      );
+    }
+    options.format = ['esm'];
+  } else if (packageJson.type === 'commonjs') {
+    if (options.format?.includes('esm')) {
+      logger.warn(
+        `Package type is set to "commonjs" but "esm" format is included. Going to use "cjs" format instead. You can change the package type to "module" or remove type in the package.json file.`
+      );
+    }
+    options.format = ['cjs'];
+  }
+
   // update package specific settings
   packageJson = getUpdatedPackageJsonContent(packageJson, options);
 
@@ -278,7 +294,7 @@ export function getUpdatedPackageJsonContent(
     packageJson.module ??= esmExports['.'];
 
     if (!hasCjsFormat) {
-      packageJson.type = 'module';
+      packageJson.type ??= 'module';
       packageJson.main ??= esmExports['.'];
     }
 
@@ -302,7 +318,7 @@ export function getUpdatedPackageJsonContent(
 
     packageJson.main ??= cjsExports['.'];
     if (!hasEsmFormat) {
-      packageJson.type = 'commonjs';
+      packageJson.type ??= 'commonjs';
     }
 
     if (options.generateExportsField) {