# 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.

# A helper for forwarding testonly and visibility.
# Forwarding "*" does not include variables from outer scopes (to avoid copying
# all globals into each template invocation), so it will not pick up
# file-scoped or outer-template-scoped variables. Normally this behavior is
# desired, but "visibility" and "testonly" are commonly defined in outer scopes.
# Explicitly forwarding them in forward_variables_from() works around this
# nuance. See //build/docs/writing_gn_templates.md#using-forward_variables_from
TESTONLY_AND_VISIBILITY = [
  "testonly",
  "visibility",
]

# ==============================================================================
# COMPONENT SETUP
# ==============================================================================

# Defines a component, which equates to a shared_library when
# is_component_build == true and a static_library otherwise.
#
# Use static libraries for the static build rather than source sets because
# many of of our test binaries link many large dependencies but often don't
# use large portions of them. The static libraries are much more efficient to
# link in this situation since only the necessary object files are linked.
#
# The invoker can override the type of the target in the non-component-build
# case by setting static_component_type to either "source_set" or
# "static_library". If unset, the default will be used.
template("component") {
  if (is_component_build) {
    _component_mode = "shared_library"
  } else if (defined(invoker.static_component_type)) {
    assert(invoker.static_component_type == "static_library" ||
           invoker.static_component_type == "source_set")
    _component_mode = invoker.static_component_type
  } else if (!defined(invoker.sources) || invoker.sources == []) {
    # When there are no sources defined, use a source set to avoid creating
    # an empty static library (which generally don't work).
    _component_mode = "source_set"
  } else {
    _component_mode = "static_library"
  }
  target(_component_mode, target_name) {
    forward_variables_from(invoker, TESTONLY_AND_VISIBILITY)
    forward_variables_from(invoker, "*", TESTONLY_AND_VISIBILITY)

    if (is_starboard) {
      if (_component_mode == "source_set") {
        configs += source_set_configs
      } else if (_component_mode == "static_library") {
        configs += static_library_configs
      } else if (_component_mode == "shared_library") {
        configs += shared_library_configs
      }
    }
  }
}

# Component defaults
set_defaults("component") {
  if (is_component_build) {
    configs = default_shared_library_configs
    if (is_android) {
      configs -= [ "//build/config/android:hide_all_but_jni_onload" ]
    }
  } else {
    configs = default_compiler_configs
  }
}