1# Copyright 2023 The Pigweed Authors 2# 3# Licensed under the Apache License, Version 2.0 (the "License"); you may not 4# use this file except in compliance with the License. You may obtain a copy of 5# the License at 6# 7# https://www.apache.org/licenses/LICENSE-2.0 8# 9# Unless required by applicable law or agreed to in writing, software 10# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT 11# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the 12# License for the specific language governing permissions and limitations under 13# the License. 14"""Utilities for manipulating GN targets.""" 15 16import re 17 18from typing import Iterable 19 20 21class GnTarget: 22 """Represents a Pigweed Build target. 23 24 Attributes: 25 attrs: Map of GN variable names to lists of values. Recognized GN list 26 variables include 'public', 'sources', 'inputs', 'deps', etc. 27 origin: Reference to the data used to generate this target, e.g. a 28 Bazel label. 29 """ 30 31 def __init__(self, target_type: str, target_name: str) -> None: 32 """Creates a GN target. 33 34 Args: 35 target_type: Type of the GN target, like 'pw_source_set'. 36 target_name: Name of the GN target. 37 """ 38 self.attrs: dict[str, list[str]] = {} 39 self.origin: str | None = None 40 self._type = target_type 41 self._name = target_name 42 43 def type(self) -> str: 44 """Returns this object's GN target_type.""" 45 return self._type 46 47 def name(self) -> str: 48 """Returns this object's GN target_name.""" 49 return self._name 50 51 def build_args(self) -> Iterable[str]: 52 """Returns a list of GN build arguments referenced in paths. 53 54 Third party source code is referenced by Pigweed build files using build 55 arguments, e.g. 'public = [ "$dir_pw_third_party_foo/bar/baz.h" ]'. This 56 method returns any build arguments used to locate source, header or 57 input files so that the BUILD.gn file can import the build argument 58 definition. 59 """ 60 build_arg_pat = re.compile(r'(\$dir_pw_third_party_[^/:]*)') 61 for field in ['public', 'sources', 'inputs', 'include_dirs']: 62 for source_path in self.attrs.get(field, []): 63 match = re.search(build_arg_pat, source_path) 64 if match: 65 yield match.group(1) 66