Refactor GN source expansions.

tools/gn/substitution_type.cc

Index: tools/gn/substitution_type.cc
diff --git a/tools/gn/substitution_type.cc b/tools/gn/substitution_type.cc
new file mode 100644
index 0000000000000000000000000000000000000000..739208ac3787cef81310a43c20b04bf0087f6710
--- /dev/null
+++ b/tools/gn/substitution_type.cc
@@ -0,0 +1,149 @@
+// Copyright 2014 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.
+
+#include "tools/gn/substitution_type.h"
+
+#include <stdlib.h>
+
+#include "tools/gn/err.h"
+
+const char* kSubstitutionNames[SUBSTITUTION_NUM_TYPES] = {
+  NULL,  // SUBSTITUTION_LITERAL
+
+  "{{source}}",  // SUBSTITUTION_SOURCE
+  "{{source_name_part}}",  // SUBSTITUTION_NAME_PART
+  "{{source_file_part}}",  // SUBSTITUTION_FILE_PART
+  "{{source_dir}}",  // SUBSTITUTION_SOURCE_DIR
+  "{{source_root_relative_dir}}",  // SUBSTITUTION_SOURCE_ROOT_RELATIVE_DIR
+  "{{source_gen_dir}}",  // SUBSTITUTION_SOURCE_GEN_DIR
+  "{{source_out_dir}}",  // SUBSTITUTION_SOURCE_OUT_DIR
+
+  "{{output}}",  // SUBSTITUTION_OUTPUT
+  "{{root_gen_dir}}",  // SUBSTITUTION_ROOT_GEN_DIR
+  "{{root_out_dir}}",  // SUBSTITUTION_ROOT_OUT_DIR
+  "{{target_gen_dir}}",  // SUBSTITUTION_TARGET_GEN_DIR
+  "{{target_out_dir}}",  // SUBSTITUTION_TARGET_OUT_DIR
+  "{{target_output_name}}",  // SUBSTITUTION_TARGET_OUTPUT_NAME
+
+  "{{cflags}}",  // SUBSTITUTION_CFLAGS
+  "{{cflags_c}}",  // SUBSTITUTION_CFLAGS_C
+  "{{cflags_cc}}",  // SUBSTITUTION_CFLAGS_CC
+  "{{cflags_objc}}",  // SUBSTITUTION_CFLAGS_OBJC
+  "{{cflags_objcc}}",  // SUBSTITUTION_CFLAGS_OBJCC
+  "{{defines}}",  // SUBSTITUTION_DEFINES
+  "{{include_dirs}}",  // SUBSTITUTION_INCLUDE_DIRS
+
+  "{{inputs}}",  // SUBSTITUTION_LINKER_INPUTS
+  "{{ldflags}}",  // SUBSTITUTION_LDFLAGS
+  "{{libs}}",  // SUBSTITUTION_LIBS
+  "{{output_extension}}",  // SUBSTITUTION_OUTPUT_EXTENSION
+  "{{solibs}}",  // SUBSTITUTION_SOLIBS
+};
+
+const char* kSubstitutionNinjaNames[SUBSTITUTION_NUM_TYPES] = {
+  NULL,  // SUBSTITUTION_LITERAL
+
+  // This isn't written by GN, the name here is referring to the Ninja variable
+  // since when we would use this would be for writing source rules.
+  "in",  // SUBSTITUTION_SOURCE
+  "source_name_part",  // SUBSTITUTION_NAME_PART
+  "source_file_part",  // SUBSTITUTION_FILE_PART
+  "source_dir",  // SUBSTITUTION_SOURCE_DIR
+  "source_root_relative_dir",  // SUBSTITUTION_SOURCE_ROOT_RELATIVE_DIR
+  "source_gen_dir",  // SUBSTITUTION_SOURCE_GEN_DIR
+  "source_out_dir",  // SUBSTITUTION_SOURCE_OUT_DIR
+
+  "output",  // SUBSTITUTION_OUTPUT
+  "root_gen_dir",  // SUBSTITUTION_ROOT_GEN_DIR
+  "root_out_dir",  // SUBSTITUTION_ROOT_OUT_DIR
+  "target_gen_dir",  // SUBSTITUTION_TARGET_GEN_DIR
+  "target_out_dir",  // SUBSTITUTION_TARGET_OUT_DIR
+  "target_output_name",  // SUBSTITUTION_TARGET_OUTPUT_NAME
+
+  "cflags",  // SUBSTITUTION_CFLAGS
+  "cflags_c",  // SUBSTITUTION_CFLAGS_C
+  "cflags_cc",  // SUBSTITUTION_CFLAGS_CC
+  "cflags_objc",  // SUBSTITUTION_CFLAGS_OBJC
+  "cflags_objcc",  // SUBSTITUTION_CFLAGS_OBJCC
+  "defines",  // SUBSTITUTION_DEFINES
+  "include_dirs",  // SUBSTITUTION_INCLUDE_DIRS
+
+  "inputs",  // SUBSTITUTION_LINKER_INPUTS
+  "ldflags",  // SUBSTITUTION_LDFLAGS
+  "libs",  // SUBSTITUTION_LIBS
+  "output_extension",  // SUBSTITUTION_OUTPUT_EXTENSION
+  "solibs",  // SUBSTITUTION_SOLIBS
+};
+
+bool SubstitutionIsInOutputDir(SubstitutionType type) {
+  return type == SUBSTITUTION_SOURCE_GEN_DIR ||
+         type == SUBSTITUTION_SOURCE_OUT_DIR;
+}
+
+bool IsValidSourceSubstitution(SubstitutionType type) {
+  return type == SUBSTITUTION_SOURCE ||
+         type == SUBSTITUTION_SOURCE_NAME_PART ||
+         type == SUBSTITUTION_SOURCE_FILE_PART ||
+         type == SUBSTITUTION_SOURCE_DIR ||
+         type == SUBSTITUTION_SOURCE_ROOT_RELATIVE_DIR ||
+         type == SUBSTITUTION_SOURCE_GEN_DIR ||
+         type == SUBSTITUTION_SOURCE_OUT_DIR;
+}
+
+bool IsValidToolSubstutition(SubstitutionType type) {
+  return type == SUBSTITUTION_OUTPUT ||
+         type == SUBSTITUTION_ROOT_GEN_DIR ||
+         type == SUBSTITUTION_ROOT_OUT_DIR ||
+         type == SUBSTITUTION_TARGET_GEN_DIR ||
+         type == SUBSTITUTION_TARGET_OUT_DIR ||
+         type == SUBSTITUTION_TARGET_OUTPUT_NAME;
+}
+
+bool IsValidCompilerSubstitution(SubstitutionType type) {
+  return IsValidToolSubstutition(type) ||
+         type == SUBSTITUTION_CFLAGS ||
+         type == SUBSTITUTION_CFLAGS_C ||
+         type == SUBSTITUTION_CFLAGS_CC ||
+         type == SUBSTITUTION_CFLAGS_OBJC ||
+         type == SUBSTITUTION_CFLAGS_OBJCC ||
+         type == SUBSTITUTION_DEFINES ||
+         type == SUBSTITUTION_INCLUDE_DIRS;
+}
+
+bool IsValidCompilerOutputsSubstitution(SubstitutionType type) {
+  // All tool types except "output" (which would be infinitely recursive).
+  return IsValidToolSubstutition(type) &&
+         type != SUBSTITUTION_OUTPUT;
+}
+
+bool IsValidLinkerSubstitution(SubstitutionType type) {
+  return IsValidToolSubstutition(type) ||
+         type == SUBSTITUTION_LINKER_INPUTS ||
+         type == SUBSTITUTION_LDFLAGS ||
+         type == SUBSTITUTION_LIBS ||
+         type == SUBSTITUTION_OUTPUT_EXTENSION ||
+         type == SUBSTITUTION_SOLIBS;
+}
+
+bool IsValidLinkerOutputsSubstitution(SubstitutionType type) {
+  // All valid compiler outputs plus the output extension.
+  return IsValidCompilerOutputsSubstitution(type) ||
+         type == SUBSTITUTION_OUTPUT_EXTENSION;
+}
+
+bool EnsureValidSourcesSubstitutions(
+    const std::vector<SubstitutionType>& types,
+    const ParseNode* origin,
+    Err* err) {
+  for (size_t i = 0; i < types.size(); i++) {
+    if (!IsValidSourceSubstitution(types[i])) {
+      *err = Err(origin, "Invalid substitution type.",
+          "The substitution " + std::string(kSubstitutionNames[i]) +
+          " isn't valid for something\n"
+          "operating on a source file such as this.");
+      return false;
+    }
+  }
+  return true;
+}