GN: Use build directory for CD for scripts

tools/gn/function_to_build_path_unittest.cc

Index: tools/gn/function_to_build_path_unittest.cc
diff --git a/tools/gn/function_to_build_path_unittest.cc b/tools/gn/function_to_build_path_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..7e01912595ca4ac75e1b6c5f520c2ea865921096
--- /dev/null
+++ b/tools/gn/function_to_build_path_unittest.cc
@@ -0,0 +1,110 @@
+// Copyright (c) 2013 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 "testing/gtest/include/gtest/gtest.h"
+#include "tools/gn/functions.h"
+#include "tools/gn/parse_tree.h"
+#include "tools/gn/test_with_scope.h"
+
+namespace {
+
+void ExpectCallEqualsString(Scope* scope,
+                            const std::string& input,
+                            const std::string& expected) {
+  std::vector<Value> args;
+  args.push_back(Value(NULL, input));
+
+  Err err;
+  FunctionCallNode function;
+  Value result = functions::RunToBuildPath(scope, &function, args, &err);
+
+  EXPECT_FALSE(err.has_error());
+  EXPECT_EQ(Value::STRING, result.type());
+  EXPECT_EQ(expected, result.string_value());
+}
+
+}  // namespace
+
+TEST(ToBuildPath, Strings) {
+  TestWithScope setup;
+  setup.build_settings()->SetBuildDir(SourceDir("//out/Debug/"));
+
+  Scope* scope = setup.scope();
+  scope->set_source_dir(SourceDir("//tools/gn/"));
+
+  // Absolute system paths are unchanged.
+  ExpectCallEqualsString(scope, "/", "/");
+  ExpectCallEqualsString(scope, "/foo", "/foo");
+  ExpectCallEqualsString(scope, "/foo/", "/foo");
+  ExpectCallEqualsString(scope, "/foo/bar.txt", "/foo/bar.txt");
+
+  // Build-file relative paths.
+  ExpectCallEqualsString(scope, ".", "../../tools/gn");
+  ExpectCallEqualsString(scope, "foo.txt", "../../tools/gn/foo.txt");
+  ExpectCallEqualsString(scope, "..", "../../tools");
+  ExpectCallEqualsString(scope, "../", "../../tools");
+  ExpectCallEqualsString(scope, "../foo.txt", "../../tools/foo.txt");
+
+  // Source-root paths.
+  ExpectCallEqualsString(scope, "//", "../..");
+  ExpectCallEqualsString(scope, "//foo/", "../../foo");
+  ExpectCallEqualsString(scope, "//foo.txt", "../../foo.txt");
+  ExpectCallEqualsString(scope, "//foo/bar.txt", "../../foo/bar.txt");
+
+  // Source-root paths. It might be nice if we detected the strings start
+  // with the build dir and collapse, but this is the current behavior.
+  ExpectCallEqualsString(scope, "//out/Debug/",
+                         "../../out/Debug");  // Could be ".".
+  ExpectCallEqualsString(scope, "//out/Debug/foo/",
+                         "../../out/Debug/foo");  // Could be "foo".
+}
+
+// Test list input.
+TEST(ToBuildPath, List) {
+  TestWithScope setup;
+  setup.build_settings()->SetBuildDir(SourceDir("//out/Debug/"));
+  setup.scope()->set_source_dir(SourceDir("//tools/gn/"));
+
+  std::vector<Value> args;
+  args.push_back(Value(NULL, Value::LIST));
+  args[0].list_value().push_back(Value(NULL, "foo.txt"));
+  args[0].list_value().push_back(Value(NULL, "bar.txt"));
+
+  Err err;
+  FunctionCallNode function;
+  Value ret = functions::RunToBuildPath(setup.scope(), &function, args, &err);
+  EXPECT_FALSE(err.has_error());
+
+  ASSERT_EQ(Value::LIST, ret.type());
+  ASSERT_EQ(2u, ret.list_value().size());
+
+  EXPECT_EQ("../../tools/gn/foo.txt", ret.list_value()[0].string_value());
+  EXPECT_EQ("../../tools/gn/bar.txt", ret.list_value()[1].string_value());
+}
+
+TEST(ToBuildPath, Errors) {
+  TestWithScope setup;
+  setup.build_settings()->SetBuildDir(SourceDir("//out/Debug/"));
+
+  // No arg input should issue an error.
+  Err err;
+  std::vector<Value> args;
+  FunctionCallNode function;
+  Value ret = functions::RunToBuildPath(setup.scope(), &function, args, &err);
+  EXPECT_TRUE(err.has_error());
+
+  // One arg int input.
+  args.push_back(Value(NULL, static_cast<int64>(5)));
+  err = Err();
+  ret = functions::RunToBuildPath(setup.scope(), &function, args, &err);
+  EXPECT_TRUE(err.has_error());
+
+  // Two arg string input.
+  args.clear();
+  args.push_back(Value(NULL, "hello"));
+  args.push_back(Value(NULL, "world"));
+  err = Err();
+  ret = functions::RunToBuildPath(setup.scope(), &function, args, &err);
+  EXPECT_TRUE(err.has_error());
+}