Adding pr comment bot that alerts if the size has increased.

.github/workflows/file-size-check.yml

@@ -0,0 +1,133 @@
+name: File Size Check
+# Trigger the workflow on PRs to the main branch. It builds the extension in prod mode and checks the size of the
+# vsix file and webview bundle file and compares it with the main branch. It fails if the size has increased by more than 10%.
+# For vsix, we also check if the size is greater than 25MB.
+
+on:
+  pull_request:
+    branches:
+      - main
+
+jobs:
+  size-check:
+    runs-on: ubuntu-latest
+
+    steps:
+      -name: Checkout main branch
+        uses: actions/checkout@v4
+        with:
+          ref: main
+          path: './main'
+
+      -name: Checkout PR branch
+        uses: actions/checkout@v4
+        with:
+          ref: ${{ github.event.pull_request.head.sha }}
+          path: './pr'
+
+      -name: Setup Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: '18'
+
+      -name: Install tools
+        run: |
+            echo "Installing Yarn"
+            npm install --global [email protected]
+            echo "Installing Gulp CLI"
+            npm install --global [email protected]
+            echo "Installing VSCE"
+            npm install --global [email protected]
+            echo "Installing gulp"
+            npm install --global [email protected]
+
+      -name: Build main branch
+        run: |
+            cd main
+            yarn --frozen-lockfile
+            yarn build --prod
+            yarn gulp package:online
+
+      -name: Build PR branch
+        run: |
+            cd pr
+            yarn --frozen-lockfile
+            yarn build --prod
+            yarn gulp package:online
+
+      -name: Calculate vsix file sizes
+        run: |
+            main_vsix=$(find ./main -name "*.vsix")
+            pr_vsix=$(find ./main -name "*.vsix")
+            main_size=$(stat -c%s "$main_vsix")
+            pr_size=$(stat -c%s "$pr_vsix")
+            size_diff=$((pr_size - main_size))
+            percentage_change=$((100 * size_diff / main_size))
+
+            echo "Main branch VSIX size: $main_size bytes"
+            echo "PR branch VSIX size: $pr_size bytes"
+            echo "Size difference: $size_diff bytes"
+            echo "Percentage change: $percentage_change%"
+
+            echo "main_vsix_size=$main_size" >> $GITHUB_ENV
+            echo "pr_vsix_size=$pr_size" >> $GITHUB_ENV
+            echo "vsix_percentage_change=$percentage_change" >> $GITHUB_ENV
+
+      -name: Calculate webview bundle sizes
+        run: |
+            main_webview_bundle=$(du -sk ./main/out/src/reactviews/assets | cut -f1)
+            pr_webview_bundle=$(du -sk ./pr/out/src/reactviews/assets | cut -f1)
+            size_diff=$((pr_size - main_size))
+            percentage_change=$((100 * size_diff / main_size))
+
+            echo "Main branch bundle size: $main_size KB"
+            echo "PR branch bundle size: $pr_size KB"
+            echo "Size difference: $size_diff KB"
+            echo "Percentage change: $percentage_change%"
+
+            echo "main_webview_bundle_size=$main_size" >> $GITHUB_ENV
+            echo "pr_webview_bundle_size=$pr_size" >> $GITHUB_ENV
+            echo "webview_bundle_percentage_change=$percentage_change" >> $GITHUB_ENV
+
+      - name: Comment on PR with bundle size difference
+        uses: actions/github-script@v7
+        with:
+          script: |
+            const mainWebviewBundleSize = process.env.main_webview_bundle_size;
+            const prWebviewBundleSize = process.env.pr_webview_bundle_size;
+            const webviewBundlePercentageChange = process.env.webview_bundle_percentage_change;
+
+            const mainVsixSize = process.env.main_vsix_size;
+            const prVsixSize = process.env.pr_vsix_size;
+            const vsixPercentageChange = process.env.vsix_percentage_change;
+
+            const comment = `
+            ### VSIX Size Comparison
+            - **Main branch VSIX size**: ${mainVsixSize} bytes
+            - **PR branch VSIX size**: ${prVsixSize} bytes
+            - **Size difference**: ${prVsixSize - mainVsixSize} bytes (${vsixPercentageChange}%)
+            ### Bundle Size Comparison
+            - **Main branch bundle size**: ${mainWebviewBundleSize} KB
+            - **PR branch bundle size**: ${prWebviewBundleSize} KB
+            - **Size difference**: ${prWebviewBundleSize - mainWebviewBundleSize} KB (${percentageChange}%)
+            `;
+
+            console.log(comment);
+
+            github.issues.createComment({
+              issue_number: context.issue.number,
+              owner: context.repo.owner,
+              repo: context.repo.repo,
+              body: comment
+            });
+
+        - name: Fail if vsix size is increased by 10% or size is above 25mb
+          if: ${{ env.vsix_percentage_change > 10 || env.pr_vsix_size > 25000000 }}
+          run: exit 1
+
+        - name: Fail if bundle size is increased by 10%
+          if: ${{ env.webview_bundle_percentage_change > 10 }}
+          run: exit 1
+
+
+