| # Copyright 2023 The Bazel Authors. All rights reserved. |
| # |
| # Licensed under the Apache License, Version 2.0 (the "License"); |
| # you may not use this file except in compliance with the License. |
| # You may obtain a copy of the License at |
| # |
| # http://www.apache.org/licenses/LICENSE-2.0 |
| # |
| # Unless required by applicable law or agreed to in writing, software |
| # distributed under the License is distributed on an "AS IS" BASIS, |
| # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| # See the License for the specific language governing permissions and |
| # limitations under the License. |
| |
| """Skylib module containing utilities for Bazel modules and module extensions.""" |
| |
| def _as_extension(macro, doc = None): |
| """Wraps a WORKSPACE dependency macro into a module extension. |
| |
| Example: |
| ```starlark |
| def rules_foo_deps(optional_arg = True): |
| some_repo_rule(name = "foobar") |
| http_archive(name = "bazqux") |
| |
| rules_foo_deps_ext = modules.as_extension(rules_foo_deps) |
| ``` |
| |
| Args: |
| macro: A [WORKSPACE dependency macro](https://bazel.build/rules/deploying#dependencies), i.e., |
| a function with no required parameters that instantiates one or more repository rules. |
| doc: A description of the module extension that can be extracted by documentation generating |
| tools. |
| |
| Returns: |
| A module extension that generates the repositories instantiated by the given macro and also |
| uses [`use_all_repos`](#use_all_repos) to indicate that all of those repositories should be |
| imported via `use_repo`. |
| """ |
| |
| def _ext_impl(module_ctx): |
| macro() |
| return _use_all_repos(module_ctx) |
| |
| return module_extension( |
| implementation = _ext_impl, |
| doc = doc, |
| ) |
| |
| def _use_all_repos(module_ctx): |
| """Return from a module extension that should have all its repositories imported via `use_repo`. |
| |
| Example: |
| ```starlark |
| def _ext_impl(module_ctx): |
| some_repo_rule(name = "foobar") |
| http_archive(name = "bazqux") |
| return modules.use_all_repos(module_ctx) |
| |
| ext = module_extension(_ext_impl) |
| ``` |
| |
| Args: |
| module_ctx: The [`module_ctx`](https://bazel.build/rules/lib/builtins/module_ctx) object |
| passed to the module extension's implementation function. |
| |
| Returns: |
| An [`extension_metadata`](https://bazel.build/rules/lib/builtins/extension_metadata.html) |
| object that, when returned from a module extension implementation function, specifies that all |
| repositories generated by this extension should be imported via `use_repo`. If the current |
| version of Bazel doesn't support `extension_metadata`, returns `None` instead, which can |
| safely be returned from a module extension implementation function in all versions of Bazel. |
| """ |
| |
| # module_ctx.extension_metadata is available in Bazel 6.2.0 and later. |
| # If not available, returning None from a module extension is equivalent to not returning |
| # anything. |
| extension_metadata = getattr(module_ctx, "extension_metadata", None) |
| if not extension_metadata: |
| return None |
| |
| # module_ctx.root_module_has_non_dev_dependency is available in Bazel 6.3.0 and later. |
| root_module_has_non_dev_dependency = getattr( |
| module_ctx, |
| "root_module_has_non_dev_dependency", |
| None, |
| ) |
| if root_module_has_non_dev_dependency == None: |
| return None |
| |
| return extension_metadata( |
| root_module_direct_deps = "all" if root_module_has_non_dev_dependency else [], |
| root_module_direct_dev_deps = [] if root_module_has_non_dev_dependency else "all", |
| ) |
| |
| modules = struct( |
| as_extension = _as_extension, |
| use_all_repos = _use_all_repos, |
| ) |