Add calculator example with channel-based state management

.github/workflows/e2e.yml

@@ -30,7 +30,7 @@ jobs:
 
       - name: Generate and build counter example
         run: |
-          ./guix generate -p examples/counter
+          ./guix generate -p examples/counter --verbose-logs
           cd examples/counter
           # Copy wasm_exec.js from Go installation
           GOROOT="$(go env GOROOT)"
@@ -65,3 +65,59 @@ jobs:
           name: playwright-results
           path: examples/counter/test-results/
           retention-days: 7
+
+  calculator:
+    name: Calculator E2E Tests
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Set up Go
+        uses: actions/setup-go@v5
+        with:
+          go-version: '1.25'
+
+      - name: Set up Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: '20'
+
+      - name: Build CLI
+        run: go build -o guix ./cmd/guix
+
+      - name: Generate and build calculator example
+        run: |
+          ./guix generate -p examples/calculator --verbose-logs
+          cd examples/calculator
+
+          # Copy wasm_exec.js from Go installation
+          GOROOT="$(go env GOROOT)"
+          if [ -f "$GOROOT/lib/wasm/wasm_exec.js" ]; then
+            cp "$GOROOT/lib/wasm/wasm_exec.js" .
+          elif [ -f "$GOROOT/misc/wasm/wasm_exec.js" ]; then
+            cp "$GOROOT/misc/wasm/wasm_exec.js" .
+          else
+            echo "wasm_exec.js not found in GOROOT, downloading from GitHub"
+            curl -o wasm_exec.js https://raw.githubusercontent.com/golang/go/go1.25.0/lib/wasm/wasm_exec.js
+          fi
+          GOOS=js GOARCH=wasm go build -o main.wasm .
+          echo "Files after build:"
+          ls -lah *.{html,js,wasm} 2>/dev/null || ls -lah
+
+      - name: Install Playwright
+        working-directory: examples/calculator
+        run: |
+          npm install
+          npx playwright install --with-deps chromium
+
+      - name: Run Playwright tests
+        working-directory: examples/calculator
+        run: npx playwright test
+
+      - name: Upload test results
+        if: always()
+        uses: actions/upload-artifact@v4
+        with:
+          name: calculator-playwright-results
+          path: examples/calculator/test-results/
+          retention-days: 7

.gitignore

@@ -16,9 +16,6 @@ go.work
 wasm_exec.js
 main.wasm
 
-# Generated files
-*_gen.go
-
 # Cache
 .guix/
 *.cache

cmd/guix/main.go

@@ -52,6 +52,10 @@ func main() {
 						Name:  "verbose",
 						Usage: "Verbose output",
 					},
+					&cli.BoolFlag{
+						Name:  "verbose-logs",
+						Usage: "Generate verbose logging statements in code (for debugging)",
+					},
 				},
 				Action: runGenerate,
 			},
@@ -77,7 +81,10 @@ func main() {
 }
 
 func generateHelpersFile(root string) error {
-	helpersContent := `// Code generated by guix. DO NOT EDIT.
+	helpersContent := `//go:build js && wasm
+// +build js,wasm
+
+// Code generated by guix. DO NOT EDIT.
 
 package main
 
@@ -115,6 +122,7 @@ func runGenerate(c *cli.Context) error {
 	watchMode := c.Bool("watch")
 	lazy := c.Bool("lazy")
 	verbose := c.Bool("verbose")
+	verboseLogs := c.Bool("verbose-logs")
 
 	// Load or create cache
 	var genCache *cache.Cache
@@ -127,13 +135,15 @@ func runGenerate(c *cli.Context) error {
 		}
 	}
 
-	// Generate helpers file first
-	if err := generateHelpersFile(path); err != nil {
-		return fmt.Errorf("failed to generate helpers: %w", err)
+	// Generate helpers file first (only if verbose logs are enabled)
+	if verboseLogs {
+		if err := generateHelpersFile(path); err != nil {
+			return fmt.Errorf("failed to generate helpers: %w", err)
+		}
 	}
 
 	// Generate all files initially
-	if err := generateAll(path, genCache, verbose); err != nil {
+	if err := generateAll(path, genCache, verbose, verboseLogs); err != nil {
 		return err
 	}
 
@@ -146,13 +156,13 @@ func runGenerate(c *cli.Context) error {
 
 	// Watch mode
 	if watchMode {
-		return watchFiles(path, genCache, verbose, lazy)
+		return watchFiles(path, genCache, verbose, verboseLogs, lazy)
 	}
 
 	return nil
 }
 
-func generateAll(root string, genCache *cache.Cache, verbose bool) error {
+func generateAll(root string, genCache *cache.Cache, verbose bool, verboseLogs bool) error {
 	p, err := parser.New()
 	if err != nil {
 		return fmt.Errorf("failed to create parser: %w", err)
@@ -191,7 +201,7 @@ func generateAll(root string, genCache *cache.Cache, verbose bool) error {
 			}
 		}
 
-		if err := generateFile(path, p, verbose); err != nil {
+		if err := generateFile(path, p, verbose, verboseLogs); err != nil {
 			return fmt.Errorf("failed to generate %s: %w", path, err)
 		}
 
@@ -231,7 +241,7 @@ func formatFile(path string) error {
 	return nil
 }
 
-func generateFile(srcPath string, p *parser.Parser, verbose bool) error {
+func generateFile(srcPath string, p *parser.Parser, verbose bool, verboseLogs bool) error {
 	if verbose {
 		log.Printf("Generating %s", srcPath)
 	}
@@ -255,6 +265,7 @@ func generateFile(srcPath string, p *parser.Parser, verbose bool) error {
 
 	// Generate Go code
 	gen := codegen.New(file.Package)
+	gen.SetVerbose(verboseLogs)
 	output, err := gen.Generate(file)
 	if err != nil {
 		return err
@@ -278,7 +289,7 @@ func generateFile(srcPath string, p *parser.Parser, verbose bool) error {
 	return nil
 }
 
-func watchFiles(root string, genCache *cache.Cache, verbose bool, lazy bool) error {
+func watchFiles(root string, genCache *cache.Cache, verbose bool, verboseLogs bool, lazy bool) error {
 	watcher, err := fsnotify.NewWatcher()
 	if err != nil {
 		return fmt.Errorf("failed to create watcher: %w", err)
@@ -346,7 +357,7 @@ func watchFiles(root string, genCache *cache.Cache, verbose bool, lazy bool) err
 
 					log.Printf("File changed: %s", event.Name)
 
-					if err := generateFile(event.Name, p, verbose); err != nil {
+					if err := generateFile(event.Name, p, verbose, verboseLogs); err != nil {
 						log.Printf("Error generating %s: %v", event.Name, err)
 					} else {
 						log.Printf("Successfully regenerated %s", event.Name)