ci: use npm to publish directly rather than yarn

.ado/jobs/npm-publish.yml

@@ -8,6 +8,9 @@ jobs:
   variables:
     - name: BUILDSECMON_OPT_IN
       value: true
+    - name: USE_YARN_FOR_PUBLISH
+      value: false
+
   timeoutInMinutes: 90
   cancelTimeoutInMinutes: 5
   templateContext:
@@ -50,8 +53,14 @@ jobs:
     # Disable Nightly publishing on the main branch
     - ${{ if endsWith(variables['Build.SourceBranchName'], '-stable') }}:
       - script: |
-          yarn config set npmPublishRegistry "https://registry.npmjs.org"
-          yarn config set npmAuthToken $(npmAuthToken)
+          if [ "$(USE_YARN_FOR_PUBLISH)" = "true" ]; then
+            echo "Configuring yarn for npm publishing"
+            yarn config set npmPublishRegistry "https://registry.npmjs.org"
+            yarn config set npmAuthToken $(npmAuthToken)
+          else
+            echo "Configuring npm for publishing"
+            echo "//registry.npmjs.org/:_authToken=$(npmAuthToken)" > ~/.npmrc
+          fi
           node .ado/scripts/prepublish-check.mjs --verbose --tag $(publishTag)
         displayName: Set and validate npm auth
         condition: and(succeeded(), eq(variables['publish_react_native_macos'], '1'))
@@ -65,19 +74,33 @@ jobs:
         condition: and(succeeded(), eq(variables['publish_react_native_macos'], '1'))
 
       - script: |
+          set -eox pipefail
           if [[ -f .rnm-publish ]]; then
             # https://github.com/microsoft/react-native-macos/issues/2580
             # `nx release publish` gets confused by the output of RNM's prepack script.
-            # Let's call `yarn npm publish` directly instead on the packages we want to publish.
+            # Let's call publish directly instead on the packages we want to publish.
             # yarn nx release publish --tag $(publishTag) --excludeTaskDependencies
-            yarn ./packages/virtualized-lists npm publish --tag $(publishTag)
-            yarn ./packages/react-native npm publish --tag $(publishTag)
+            if [ "$(USE_YARN_FOR_PUBLISH)" = "true" ]; then
+              echo "Publishing with yarn npm publish"
+              yarn ./packages/virtualized-lists npm publish --tag $(publishTag)
+              yarn ./packages/react-native npm publish --tag $(publishTag)
+            else
+              echo "Publishing with npm publish"
+              (cd ./packages/virtualized-lists && npm publish --tag $(publishTag))
+              (cd ./packages/react-native && npm publish --tag $(publishTag))
+            fi
           fi
         displayName: Publish packages
         condition: and(succeeded(), eq(variables['publish_react_native_macos'], '1'))
 
     - script: |
-        yarn config unset npmAuthToken
-        yarn config unset npmPublishRegistry
-      displayName: Unset npm configuration
+        if [ "$(USE_YARN_FOR_PUBLISH)" = "true" ]; then
+          echo "Cleaning up yarn npm configuration"
+          yarn config unset npmAuthToken || true
+          yarn config unset npmPublishRegistry || true
+        else
+          echo "Cleaning up npm configuration"
+          rm -f ~/.npmrc
+        fi
+      displayName: Remove NPM auth configuration
       condition: always()

.ado/scripts/prepublish-check.mjs

@@ -160,14 +160,10 @@ function verifyNpmAuth(registry = NPM_DEFEAULT_REGISTRY) {
     const whoamiArgs = ["npm", "whoami", "--publish"];
     const whoami = spawnSync("yarn", whoamiArgs, spawnOptions);
     if (whoami.status !== 0) {
-      const stderr = whoami.stderr.toString().trim();
-      const stdout = whoami.stdout.toString().trim();
-      const errorOutput = stderr || stdout || 'No error message available';
-
-      // Yarn uses different error format
-      if (errorOutput.includes("Invalid authentication") || errorOutput.includes("Failed with errors")) {
-        throw new Error(`Invalid or missing auth token for registry: ${registry}`);
-      }
+      const errorOutput =
+        whoami.stderr.toString().trim() ||
+        whoami.stdout.toString().trim() ||
+        'No error message available';
 
       // Provide more context about the yarn authentication failure
       throw new Error(`Yarn authentication failed (exit code ${whoami.status}): ${errorOutput}`);