build/copy_tree.gni

# Copyright (c) 2017, the Dart project authors.  Please see the AUTHORS file
# for details. All rights reserved. Use of this source code is governed by a
# BSD-style license that can be found in the LICENSE file.

_dart_root = rebase_path("..")

# copy_tree() copies a directory tree rooted at `source` to `dest`, which should
# be somewhere under $root_out_dir.
#
# Optional parameters:
# exclude - A comma separated list that is passed to shutil.ignore_patterns()
#           in tools/copy_tree.py.
template("_copy_tree") {
  assert(defined(invoker.source), "copy_tree must define 'source'")
  assert(defined(invoker.dest), "copy_tree must define 'dest'")
  assert(defined(invoker.inputs), "copy_tree must define 'inputs'")
  source = invoker.source
  dest = invoker.dest
  inputs = invoker.inputs
  action(target_name) {
    if (defined(invoker.visibility)) {
      visibility = invoker.visibility
    }

    deps = []
    if (defined(invoker.deps)) {
      deps += invoker.deps
    }

    common_args = [
      "--from",
      rebase_path(source),
      "--to",
      rebase_path(dest),
    ]
    if (defined(invoker.exclude)) {
      common_args += [
        "--exclude",
        invoker.exclude,
      ]
    }

    relative_files = rebase_path(inputs, rebase_path(source))

    output_files = []
    foreach(input, relative_files) {
      output_files += [ "$dest/$input" ]
    }

    outputs = output_files
    script = "$_dart_root/tools/copy_tree.py"
    args = common_args
  }
}

# copy_trees() arranges to invoke copy_tree.py only once to gather the list of
# input source files for every _copy_tree() target. It takes a list of scopes as
# a parameter. The scopes should contain the following mappings.
#
# target: The target name for the _copy_tree() target.
# visibility: The visibility for the _copy_tree() target.
# source: The source directory relative to this directory.
# dest: The destination directory for the _copy_tree() target.
# deps: Any deps needed for the _copy_tree() target.
# ignore_patterns: Patterns to ignore when walking the directory tree.
#                  This should be '{}' if nothing should be ignored.
#
# copy_trees() will then make sure each invocation of _copy_tree() has the
# correct 'inputs' parameter
template("copy_trees") {
  assert(defined(invoker.sources), "$target_name must define 'source'")
  sources = invoker.sources
  copy_tree_source_paths = []
  foreach(copy_tree_spec, sources) {
    copy_tree_source_paths += [
      rebase_path(copy_tree_spec.source),
      copy_tree_spec.ignore_patterns
    ]
  }

  # Evaluate script output as GN, producing a scope containing a single value
  # "sources"
  copy_tree_inputs_scope = exec_script("$_dart_root/tools/copy_tree.py",
                                       ["--gn"] + copy_tree_source_paths,
                                       "scope")

  # A list of lists of input source files for copy_tree.
  copy_tree_inputs = copy_tree_inputs_scope.sources
  copy_tree_inputs_index = 0
  foreach(copy_tree_spec, sources) {
    _copy_tree(copy_tree_spec.target) {
      visibility = copy_tree_spec.visibility
      source = copy_tree_spec.source
      dest = copy_tree_spec.dest
      inputs = copy_tree_inputs[copy_tree_inputs_index]
      if (defined(copy_tree_spec.deps)) {
        deps = copy_tree_spec.deps
      }
      if (copy_tree_spec.ignore_patterns != "{}") {
        exclude = copy_tree_spec.ignore_patterns
      }
    }
    copy_tree_inputs_index = copy_tree_inputs_index + 1
  }
}