Allow Optional Args With Extract

internal/app/app.go

@@ -300,7 +300,8 @@ func runExtract(ctx context) error {
 		return err
 	}
 
-	result, err := pipeline.Extract(p)
+	files := ctx.args[1:]
+	result, err := pipeline.Extract(p, files...)
 	if err != nil {
 		return err
 	}

internal/pipeline/extract.go

@@ -24,29 +24,37 @@ type ExtractResult struct {
 	Skipped     int
 }
 
-func Extract(p *project.Project) (ExtractResult, error) {
+func Extract(p *project.Project, files ...string) (ExtractResult, error) {
-	modulePath := filepath.Join(p.BuildDir(), p.Config.Module.ResRef+".mod")
-	input, err := os.Open(modulePath)
-	if err != nil {
-		return ExtractResult{}, fmt.Errorf("open module archive: %w", err)
-	}
-	defer input.Close()
-
-	archive, err := erf.Read(input)
-	if err != nil {
-		return ExtractResult{}, fmt.Errorf("read module archive: %w", err)
-	}
-
 	var result ExtractResult
-	result.ModulePath = modulePath
 	var failures []error
 	desired := map[string]struct{}{}
 
-	written, overwritten, skipped, errs := extractArchiveResources(p, archive, desired)
+	allowed := make(map[string]bool)
-	result.Written += written
+	for _, f := range files {
-	result.Overwritten += overwritten
+		allowed[f] = true
-	result.Skipped += skipped
+	}
-	failures = append(failures, errs...)
+
+	shouldExtractMod := len(allowed) == 0 || allowed[p.Config.Module.ResRef+".mod"]
+	if shouldExtractMod {
+		modulePath := filepath.Join(p.BuildDir(), p.Config.Module.ResRef+".mod")
+		input, err := os.Open(modulePath)
+		if err != nil {
+			return ExtractResult{}, fmt.Errorf("open module archive: %w", err)
+		}
+		defer input.Close()
+
+		archive, err := erf.Read(input)
+		if err != nil {
+			return ExtractResult{}, fmt.Errorf("read module archive: %w", err)
+		}
+
+		result.ModulePath = modulePath
+		written, overwritten, skipped, errs := extractArchiveResources(p, archive, desired)
+		result.Written += written
+		result.Overwritten += overwritten
+		result.Skipped += skipped
+		failures = append(failures, errs...)
+	}
 
 	hakPaths, err := filepath.Glob(filepath.Join(p.BuildDir(), "*.hak"))
 	if err != nil {
@@ -54,6 +62,11 @@ func Extract(p *project.Project) (ExtractResult, error) {
 	}
 	slices.Sort(hakPaths)
 	for _, hakPath := range hakPaths {
+		filename := filepath.Base(hakPath)
+		if len(allowed) > 0 && !allowed[filename] {
+			continue
+		}
+
 		input, err := os.Open(hakPath)
 		if err != nil {
 			failures = append(failures, fmt.Errorf("open hak archive %s: %w", hakPath, err))