Switch to new interfaces

LICENSE

@@ -1,4 +1,4 @@
-Copyright 2015-2019 Alex Yatskov
+Copyright 2015-2021 Alex Yatskov
 
 Permission is hereby granted, free of charge, to any person obtaining a copy of
 this software and associated documentation files (the "Software"), to deal in

cache.go

@@ -75,7 +75,7 @@ func (cache *cache) buildCachePath(context *Context, outputPath string, inputFil
 	hasher.Write(uintBuff)
 	hasher.Write([]byte(outputPath))
 
-	sort.Sort(FilesByPath(inputFiles))
+	sort.Sort(filesByPath(inputFiles))
 	for _, inputFile := range inputFiles {
 		fileHash, err := inputFile.hash()
 		if err != nil {

context.go

@@ -17,7 +17,9 @@ type Context struct {
 	plugin Plugin
 	hash   uint32
 
-	fileFilters []Filter
+	filtersExternal filterStack
+	filtersInternal filterStack
+
 	inputFiles  chan *File
 	outputFiles chan *File
 }
@@ -74,14 +76,17 @@ func (context *Context) RetrieveCachedFile(outputPath string, inputFiles ...*Fil
 	return context.goldsmith.retrieveFile(context, outputPath, inputFiles)
 }
 
+// Specify internal filter(s) that exclude files from being processed.
+func (context *Context) Filter(filters ...Filter) *Context {
+	context.filtersInternal = filters
+	return context
+}
+
 func (context *Context) step() {
 	defer close(context.outputFiles)
 
-	var err error
-	var filter Filter
 	if initializer, ok := context.plugin.(Initializer); ok {
-		filter, err = initializer.Initialize(context)
-		if err != nil {
+		if err := initializer.Initialize(context); err != nil {
 			context.goldsmith.fault(context.plugin.Name(), nil, err)
 			return
 		}
@@ -96,26 +101,7 @@ func (context *Context) step() {
 			go func() {
 				defer wg.Done()
 				for inputFile := range context.inputFiles {
-					var fileFilters []Filter
-					fileFilters = append(fileFilters, context.fileFilters...)
-					if filter != nil {
-						fileFilters = append(fileFilters, filter)
-					}
-
-					var accept bool
-					if processor != nil {
-						for _, fileFilter := range fileFilters {
-							if accept, err = fileFilter.Accept(inputFile); err != nil {
-								context.goldsmith.fault(fileFilter.Name(), inputFile, err)
-								return
-							}
-							if !accept {
-								break
-							}
-						}
-					}
-
-					if accept {
+					if processor != nil && context.filtersInternal.accept(inputFile) && context.filtersExternal.accept(inputFile) {
 						if _, err := inputFile.Seek(0, os.SEEK_SET); err != nil {
 							context.goldsmith.fault("core", inputFile, err)
 						}

file.go

@@ -186,17 +186,17 @@ func (file *File) hash() (uint32, error) {
 	return file.hashValue, nil
 }
 
-type FilesByPath []*File
+type filesByPath []*File
 
-func (file FilesByPath) Len() int {
+func (file filesByPath) Len() int {
 	return len(file)
 }
 
-func (file FilesByPath) Swap(i, j int) {
+func (file filesByPath) Swap(i, j int) {
 	file[i], file[j] = file[j], file[i]
 }
 
-func (file FilesByPath) Less(i, j int) bool {
+func (file filesByPath) Less(i, j int) bool {
 	return strings.Compare(file[i].Path(), file[j].Path()) < 0
 }
 
@@ -227,3 +227,28 @@ func scanDir(rootDir string, infos chan fileInfo) {
 		return err
 	})
 }
+
+type filterStack []Filter
+
+func (filters *filterStack) accept(file *File) bool {
+	for _, filter := range *filters {
+		if !filter.Accept(file) {
+			return false
+		}
+	}
+
+	return true
+}
+
+func (filters *filterStack) push(filter Filter) {
+	*filters = append(*filters, filter)
+}
+
+func (filters *filterStack) pop() {
+	count := len(*filters)
+	if count == 0 {
+		panic("attempted to pop empty filter stack")
+	}
+
+	*filters = (*filters)[:count-1]
+}

goldsmith.go

@@ -18,11 +18,11 @@ type Goldsmith struct {
 	contexts      []*Context
 	contextHasher hash.Hash32
 
-	fileRefs    map[string]bool
-	fileFilters []Filter
-	fileCache   *cache
+	fileRefs  map[string]bool
+	fileCache *cache
 
-	clean bool
+	filters filterStack
+	clean   bool
 
 	errors []error
 	mutex  sync.Mutex
@@ -63,7 +63,7 @@ func (goldsmith *Goldsmith) Chain(plugin Plugin) *Goldsmith {
 		outputFiles: make(chan *File),
 	}
 
-	context.fileFilters = append(context.fileFilters, goldsmith.fileFilters...)
+	context.filtersExternal = append(context.filtersExternal, goldsmith.filters...)
 
 	if len(goldsmith.contexts) > 0 {
 		context.inputFiles = goldsmith.contexts[len(goldsmith.contexts)-1].outputFiles
@@ -75,18 +75,13 @@ func (goldsmith *Goldsmith) Chain(plugin Plugin) *Goldsmith {
 
 // FilterPush pushes a filter instance on the chain's filter stack.
 func (goldsmith *Goldsmith) FilterPush(filter Filter) *Goldsmith {
-	goldsmith.fileFilters = append(goldsmith.fileFilters, filter)
+	goldsmith.filters.push(filter)
 	return goldsmith
 }
 
 // FilterPop pops a filter instance from the chain's filter stack.
 func (goldsmith *Goldsmith) FilterPop() *Goldsmith {
-	count := len(goldsmith.fileFilters)
-	if count == 0 {
-		panic("attempted to pop empty filter stack")
-	}
-
-	goldsmith.fileFilters = goldsmith.fileFilters[:count-1]
+	goldsmith.filters.pop()
 	return goldsmith
 }
 
@@ -99,21 +94,10 @@ func (goldsmith *Goldsmith) End(targetDir string) []error {
 	}
 
 	context := goldsmith.contexts[len(goldsmith.contexts)-1]
-
-export:
 	for file := range context.outputFiles {
-		for _, fileFilter := range goldsmith.fileFilters {
-			accept, err := fileFilter.Accept(file)
-			if err != nil {
-				goldsmith.fault(fileFilter.Name(), file, err)
-				continue export
-			}
-			if !accept {
-				continue export
-			}
+		if goldsmith.filters.accept(file) {
+			goldsmith.exportFile(file)
 		}
-
-		goldsmith.exportFile(file)
 	}
 
 	if goldsmith.clean {

interface.go

@@ -9,7 +9,7 @@ type Plugin interface {
 // Initializer is used to optionally initialize a plugin and to specify a
 // filter to be used for determining which files will be processed.
 type Initializer interface {
-	Initialize(context *Context) (Filter, error)
+	Initialize(context *Context) error
 }
 
 // Processor allows for optional processing of files passing through a plugin.
@@ -26,5 +26,5 @@ type Finalizer interface {
 // Filter is used to determine which files should continue in the chain.
 type Filter interface {
 	Name() string
-	Accept(file *File) (bool, error)
+	Accept(file *File) bool
 }

loader.go

@@ -10,7 +10,7 @@ func (*loader) Name() string {
 	return "loader"
 }
 
-func (*loader) Initialize(ctx *Context) (Filter, error) {
+func (*loader) Initialize(ctx *Context) error {
 	infos := make(chan fileInfo)
 	go scanDir(ctx.goldsmith.sourceDir, infos)
 
@@ -32,5 +32,5 @@ func (*loader) Initialize(ctx *Context) (Filter, error) {
 		ctx.DispatchFile(file)
 	}
 
-	return nil, nil
+	return nil
 }