A mojom .d generator.

mojom/mojom_parser/generators/common/common.go

Index: mojom/mojom_parser/generators/common/common.go
diff --git a/mojom/mojom_parser/generators/common/common.go b/mojom/mojom_parser/generators/common/common.go
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+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package common
+
+import (
+	"mojom/mojom_parser/generated/mojom_files"
+)
+
+// common groups together functions which make it easier for generators
+// implemented in go to implement the same interface.
+
+// GeneratorConfig is used to specify configuration for a generator.
+type GeneratorConfig interface {
+	// FileGraph returns a parsed MojomFileGraph.
+	FileGraph() *mojom_files.MojomFileGraph
+
+	// OutputDir returns an absolute path in which generator output must be
+	// written.
+	OutputDir() string
+
+	// SrcRootPath returns an absolute path to the root of the source tree. This
+	// is used to compute the relative path from the root of the source tree to
+	// mojom files for which output is to be generated.
+	SrcRootPath() string
+
+	// GenImports returns true if the generator should generate output files for
+	// all of the files in the provided file graph, including those that were not
+	// specified on the command line but are only present because they were
+	// referenced in an import statement. It returns false if the generator should
+	// generate output files only for the files which were explicitly specified
+	// (as indicated by the fact that they have a non-empty |SpecifiedFileName|).
+	GenImports() bool
+}
+
+// Writer is the interface used by the generators to write their output.
+// It is also made to faciliate testing by allowing generator code to write
+// to a provided buffer such as a bytes.Buffer.
+type Writer interface {
+	WriteString(s string) (n int, err error)
+}
+
+// writeOutput is the type of the generator function which writes the specified
+// file's generated code.
+type writeOutput func(fileName string, config GeneratorConfig)
+
+// GenerateOutput iterates through the files in the file graph in |config| and
+// for all the files for which an output should be generated, it uses
+// writeOutput to write the generated output.
+func GenerateOutput(writeOutput writeOutput, config GeneratorConfig) {
+	for fileName, file := range config.FileGraph().Files {
+		if config.GenImports() || *file.SpecifiedFileName != "" {
+			writeOutput(fileName, config)
+		}
+	}
+}