Reference written files relatively when possible.

tools/gn/ninja_build_writer.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 "tools/gn/ninja_build_writer.h"
 
 #include <fstream>
 #include <map>
 
 #include "base/command_line.h"
@@ skipping 134 matching lines @@
   out_ << "  description = Regenerating ninja files\n";
   out_ << "  restat = 1\n\n";
 
   // This rule will regenerate the ninja files when any input file has changed,
   // or is missing.
   out_ << "build build.ninja";
 
   // Other files read by the build.
   EscapeOptions path_escaping;
   path_escaping.mode = ESCAPE_NINJA_COMMAND;
+
   std::vector<SourceFile> written_files = g_scheduler->GetWrittenFiles();
-  for (const auto& written_file : written_files)
-    out_ << " " <<
-        EscapeString(FilePathToUTF8(build_settings_->GetFullPath(written_file)),
-                     path_escaping, nullptr);
+  for (const auto& written_file : written_files) {
+    Err err;
+    base::FilePath::StringType fileref = ComputeStringInOutputDir(

[brettw, 2015/07/31 23:36:55]

I think RebasePath in filesystem_utils.h will handle all cases of converting a
SourceFile string to be relative to a given directory. If not, we should fix it.

+        build_settings_->build_dir(), written_file, &err);
+    out_ << " ";
+    if (!err.has_error())
+      EscapeStringToStream(out_, FilePathToUTF8(fileref), path_escaping);
+    else
+      EscapeStringToStream(out_,
+          written_file.Resolve(build_settings_->root_path()), path_escaping);

[Peter Mayo, 2015/07/31 19:08:07]

Oops, forgot to change to UTF8.

+  }
 
   out_ << ": gn\n"
        << "  generator = 1\n"
        << "  depfile = build.ninja.d\n";
 
   // Input build files. These go in the ".d" file. If we write them as
   // dependencies in the .ninja file itself, ninja will expect the files to
   // exist and will error if they don't. When files are listed in a depfile,
   // missing files are ignored.
   dep_out_ << "build.ninja:";
@@ skipping 155 matching lines @@
   EscapeOptions ninja_escape;
   ninja_escape.mode = ESCAPE_NINJA;
 
   // Escape for special chars Ninja will handle.
   std::string escaped = EscapeString(phony_name, ninja_escape, nullptr);
 
   out_ << "build " << escaped << ": phony ";
   path_output_.WriteFile(out_, target_file);
   out_ << std::endl;
 }