Improve CLI interface of C++ enums to Java generator

build/config/android/rules.gni

 # 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.
 
 import("//base/android/linker/config.gni")
 import("//build/config/android/config.gni")
 import("//build/config/android/internal_rules.gni")
 import("//tools/grit/grit_rule.gni")
 import("//tools/relocation_packer/config.gni")
 
@@ skipping 305 matching lines @@
 # android_library target's srcjar_deps will make the generated java files be
 # included in that library's final outputs.
 #
 # Variables
 #   sources: list of files to be processed by the script. For each annotated
 #     enum contained in the sources files the script will generate a .java
 #     file with the same name as the name of the enum.
 #
 #   outputs: list of outputs, relative to the output_dir. These paths are
 #     verified at build time by the script. To get the list programatically run:
-#       python build/android/gyp/java_cpp_enum.py --output_dir=. \
-#         --print_output_only path/to/header/file.h
+#       python build/android/gyp/java_cpp_enum.py \
+#         --print_output_only . path/to/header/file.h
 #
 # Example
 #   java_cpp_enum("foo_generated_enum") {
 #     sources = [
 #       "src/native_foo_header.h",
 #     ]
 #     outputs = [
 #       "org/chromium/FooEnum.java",
 #     ]
 #   }
 template("java_cpp_enum") {
   set_sources_assignment_filter([])
   if (defined(invoker.testonly)) {
     testonly = invoker.testonly
   }
 
   assert(defined(invoker.sources))
   assert(defined(invoker.outputs))
 
   action("${target_name}__generate_enum") {
     sources = invoker.sources
     script = "//build/android/gyp/java_cpp_enum.py"
     gen_dir = "${target_gen_dir}/${target_name}/enums"
     outputs =
         get_path_info(rebase_path(invoker.outputs, ".", gen_dir), "abspath")
 
-    args = [
-      "--output_dir",
-      rebase_path(gen_dir, root_build_dir),
-    ]
+    args = []
     foreach(output, rebase_path(outputs, root_build_dir)) {
       args += [
         "--assert_file",
         output,
       ]
     }
+    args += rebase_path(gen_dir, root_build_dir)

[cjhopman, 2015/02/17 21:38:25]

gen_dir is a string (invoker.sources below is a list).

This should be:
args += [rebase_path(gen_dir, root_build_dir)]

or to look like the one below it:
args += rebase_path([gen_dir], root_build_dir)

[mnaganov (inactive), 2015/02/23 11:35:26]

I was supposing that gn can handle coercion itself. Fixed.

     args += rebase_path(invoker.sources, root_build_dir)
   }
 
   generate_enum_outputs = get_target_outputs(":${target_name}__generate_enum")
   base_gen_dir =
       get_label_info(":${target_name}__generate_enum", "target_gen_dir")
 
   srcjar_path = "${target_gen_dir}/${target_name}.srcjar"
   zip("${target_name}__zip_srcjar") {
     inputs = generate_enum_outputs
@@ skipping 1353 matching lines @@
 template("uiautomator_test") {
   set_sources_assignment_filter([])
   if (defined(invoker.testonly)) {
     testonly = invoker.testonly
   }
   assert(target_name != "")
   assert(invoker.deps != [] || true)
   group(target_name) {
   }
 }