Reference written files relatively when possible.

tools/gn/filesystem_utils_unittest.cc

 // 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 "base/files/file_path.h"
 #include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
 #include "build/build_config.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "tools/gn/filesystem_utils.h"
@@ skipping 101 matching lines @@
   EXPECT_TRUE(
       EnsureStringIsInOutputDir(output_dir, "//out/Debug/foo", nullptr, &err));
   EXPECT_FALSE(err.has_error());
 
   // Pattern but no template expansions are allowed.
   EXPECT_FALSE(EnsureStringIsInOutputDir(output_dir, "{{source_gen_dir}}",
                                          nullptr, &err));
   EXPECT_TRUE(err.has_error());
 }
 
+TEST(FilesystemUtils, ComputeStringInOutputDir) {
+  SourceDir out_d("//out/Debug/");
+  SourceFile foo("//foo");
+  SourceFile debugit("//out/Debugit");
+  SourceFile out_less("//out/Debug");
+
+  // Some outside.
+  Err err;
+  EXPECT_EQ("", ComputeStringInOutputDir(out_d, foo, &err));
+  EXPECT_TRUE(err.has_error());
+
+  err = Err();
+  EXPECT_EQ("", ComputeStringInOutputDir(out_d, debugit, &err));
+  EXPECT_TRUE(err.has_error());
+
+  // Some inside.
+  err = Err();
+  EXPECT_EQ("", ComputeStringInOutputDir(out_d, out_less, &err));
+  EXPECT_TRUE(err.has_error());
+
+  err = Err();
+  const char * const r_a = "a";
+  SourceFile a("//out/Debug/a");
+  EXPECT_EQ(r_a, ComputeStringInOutputDir(out_d, a, &err));
+  EXPECT_FALSE(err.has_error());
+
+  err = Err();
+  const char * const r_ofoo = "foo";
+  SourceFile ofoo("//out/Debug/foo");
+  EXPECT_EQ(r_ofoo, ComputeStringInOutputDir(out_d, ofoo, &err));
+  EXPECT_FALSE(err.has_error());
+
+  err = Err();
+  const char * const r_olong = "super-cal/bong/pas";
+  SourceFile olong("//out/Debug/super-cal/bong/pas");
+  EXPECT_EQ(r_olong, ComputeStringInOutputDir(out_d, olong, &err));
+  EXPECT_FALSE(err.has_error());
+
+  // Pattern but no template expansions are allowed.
+  SourceFile wrong("//{{source_gen_dir}}");
+  EXPECT_EQ("", ComputeStringInOutputDir(out_d, wrong, &err));
+  EXPECT_TRUE(err.has_error());
+
+}
+
 TEST(FilesystemUtils, IsPathAbsolute) {
   EXPECT_TRUE(IsPathAbsolute("/foo/bar"));
   EXPECT_TRUE(IsPathAbsolute("/"));
   EXPECT_FALSE(IsPathAbsolute(""));
   EXPECT_FALSE(IsPathAbsolute("//"));
   EXPECT_FALSE(IsPathAbsolute("//foo/bar"));
 
 #if defined(OS_WIN)
   EXPECT_TRUE(IsPathAbsolute("C:/foo"));
   EXPECT_TRUE(IsPathAbsolute("C:/"));
@@ skipping 456 matching lines @@
   EXPECT_EQ("gen/", GetToolchainGenDirAsOutputFile(&settings).value());
   EXPECT_EQ("//obj/",
             GetOutputDirForSourceDir(&settings, SourceDir("//")).value());
   EXPECT_EQ("obj/",
             GetOutputDirForSourceDirAsOutputFile(
                 &settings, SourceDir("//")).value());
   EXPECT_EQ("gen/",
             GetGenDirForSourceDirAsOutputFile(
                 &settings, SourceDir("//")).value());
 }