Support _test.gox files by generating _gox_test.go output

Go requires test files to end with _test.go. This maps
foo_test.gox → foo_gox_test.go so the test runner picks them up.

Author: germtb

.gitignore

@@ -8,7 +8,9 @@ cmd/gox/gox
 # so consumers can `go get` without needing gox installed.
 # See README.md for details.
 *_gox.go
+*_gox_test.go
 *_gox.go.map
+*_gox_test.go.map
 
 # IDE
 .idea/

CLAUDE.md

@@ -37,7 +37,7 @@ go build -o /tmp/gox ./cmd/gox
 
 ## Code Generation
 
-Generated files use the `_gox.go` suffix (e.g., `app.gox` → `app_gox.go`).
+Generated files use the `_gox.go` suffix (e.g., `app.gox` → `app_gox.go`). Test files use `_gox_test.go` (e.g., `features_test.gox` → `features_gox_test.go`).
 
 The generator produces code like:
 ```go
@@ -69,4 +69,4 @@ The LSP proxies to gopls for Go intelligence. Key behaviors:
 
 Generated files should NOT be committed. They are:
 - Created in temp directories during `gox run/build` (overlay mode)
-- Gitignored via `*_gox.go` pattern
+- Gitignored via `*_gox.go` and `*_gox_test.go` patterns

README.md

@@ -172,7 +172,9 @@ Example `.gitignore` for applications:
 
 ```gitignore
 *_gox.go
+*_gox_test.go
 *_gox.go.map
+*_gox_test.go.map
 ```
 
 ## Typed Props

cmd/gox/main.go

@@ -342,10 +342,19 @@ func processFile(inputPath string, cfg *generateConfig) error {
 }
 
 // getOutputPath determines the output path for a .gox file.
+// Test files get special handling: foo_test.gox → foo_gox_test.go
+// so that Go's test runner recognizes them.
 func getOutputPath(inputPath, outputDir string) string {
-	// Replace .gox with _gox.go
 	baseName := strings.TrimSuffix(filepath.Base(inputPath), ".gox")
-	outputName := baseName + "_gox.go"
+
+	var outputName string
+	if strings.HasSuffix(baseName, "_test") {
+		// foo_test.gox → foo_gox_test.go
+		outputName = strings.TrimSuffix(baseName, "_test") + "_gox_test.go"
+	} else {
+		// foo.gox → foo_gox.go
+		outputName = baseName + "_gox.go"
+	}
 
 	if outputDir != "" {
 		return filepath.Join(outputDir, outputName)
@@ -602,7 +611,7 @@ func runGoCommand(goCmd string, args []string) error {
 
 	// Write generated files to source directories for vet compatibility.
 	// go vet doesn't read files through the overlay, so the files must exist
-	// on disk. These are gitignored via *_gox.go and cleaned up after the command.
+	// on disk. These are gitignored via *_gox.go / *_gox_test.go and cleaned up after the command.
 	overlayData, err := os.ReadFile(overlayFile.Name())
 	if err != nil {
 		return fmt.Errorf("reading overlay: %w", err)
@@ -688,8 +697,8 @@ func remapErrorLine(line string, sourceMaps map[string]*generator.SourceMap) str
 	colNum, _ := strconv.Atoi(matches[3])
 	message := matches[4]
 
-	// Check if this is a generated _gox.go file
-	if !strings.HasSuffix(filePath, "_gox.go") {
+	// Check if this is a generated gox file (_gox.go or _gox_test.go)
+	if !strings.HasSuffix(filePath, "_gox.go") && !strings.HasSuffix(filePath, "_gox_test.go") {
 		return line
 	}
 

lsp/proxy.go

@@ -430,9 +430,13 @@ func (p *Proxy) generateAndCache(uri, text string) string {
 
 // goxToGoPath converts a .gox path to the generated .go path.
 // The .go file is placed next to the .gox file for same-package context.
+// Test files get special handling: foo_test.gox → foo_gox_test.go
 func (p *Proxy) goxToGoPath(goxPath string) string {
-	// e.g., /path/to/app.gox -> /path/to/app_gox.go
-	return strings.TrimSuffix(goxPath, ".gox") + "_gox.go"
+	base := strings.TrimSuffix(goxPath, ".gox")
+	if strings.HasSuffix(base, "_test") {
+		return strings.TrimSuffix(base, "_test") + "_gox_test.go"
+	}
+	return base + "_gox.go"
 }
 
 // rewriteURIs rewrites file URIs in a message.
@@ -447,7 +451,7 @@ func (p *Proxy) rewriteURIs(obj any, toGo bool) {
 						goxPath := uriToPath(uri)
 						goPath := p.goxToGoPath(goxPath)
 						v[key] = pathToURI(goPath)
-					} else if !toGo && strings.HasSuffix(uri, "_gox.go") {
+					} else if !toGo && (strings.HasSuffix(uri, "_gox.go") || strings.HasSuffix(uri, "_gox_test.go")) {
 						// Find original .gox file from source map
 						goPath := uriToPath(uri)
 						p.mu.RLock()

lsp/proxy_test.go

@@ -200,6 +200,8 @@ func TestGoxToGoPath(t *testing.T) {
 		{"/path/to/app.gox", "/path/to/app_gox.go"},
 		{"/Users/test/component.gox", "/Users/test/component_gox.go"},
 		{"relative/path.gox", "relative/path_gox.go"},
+		{"/path/to/features_test.gox", "/path/to/features_gox_test.go"},
+		{"relative/app_test.gox", "relative/app_gox_test.go"},
 	}
 
 	for _, tt := range tests {