Gather variable metadata for the new rule-based toolchain.
BEGIN_PUBLIC
Gather variable metadata for the new rule-based toolchain.
END_PUBLIC
PiperOrigin-RevId: 622000877
Change-Id: I5b2ea6c363fc43fd44e60ffc8fa7ae041545337e
diff --git a/cc/toolchains/cc_toolchain_info.bzl b/cc/toolchains/cc_toolchain_info.bzl
index 0429ad2..3a499f6 100644
--- a/cc/toolchains/cc_toolchain_info.bzl
+++ b/cc/toolchains/cc_toolchain_info.bzl
@@ -73,6 +73,7 @@
"files": "(depset[File]) The files required to use this variable",
"requires_types": "(dict[str, str]) A mapping from variables to their expected type name (not type). This means that we can require the generic type Option, rather than an Option[T]",
"legacy_flag_group": "(flag_group) The flag_group this corresponds to",
+ "unwrap_options": "(List[str]) A list of variables for which we should unwrap the option. For example, if a user writes `requires_not_none = \":foo\"`, then we change the type of foo from Option[str] to str",
},
)
@@ -83,7 +84,7 @@
"label": "(Label) The label defining this provider. Place in error messages to simplify debugging",
"actions": "(depset[ActionTypeInfo]) The set of actions this is associated with",
"requires_any_of": "(Sequence[FeatureConstraintInfo]) This will be enabled if any of the listed predicates are met. Equivalent to with_features",
- "nested": "(Optional[NestedArgsInfo]) The args to expand. Equivalent to a flag group.",
+ "nested": "(Optional[NestedArgsInfo]) The args expand. Equivalent to a flag group.",
"files": "(depset[File]) Files required for the args",
"env": "(dict[str, str]) Environment variables to apply",
},
diff --git a/cc/toolchains/format.bzl b/cc/toolchains/format.bzl
new file mode 100644
index 0000000..bdbb0c8
--- /dev/null
+++ b/cc/toolchains/format.bzl
@@ -0,0 +1,26 @@
+# Copyright 2024 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.
+"""Functions to format arguments for the cc toolchain"""
+
+def format_arg(format, value = None):
+ """Generate metadata to format a variable with a given value.
+
+ Args:
+ format: (str) The format string
+ value: (Optional[Label]) The variable to format. Any is used because it can
+ be any representation of a variable.
+ Returns:
+ A struct corresponding to the formatted variable.
+ """
+ return struct(format_type = "format_arg", format = format, value = value)
diff --git a/cc/toolchains/impl/nested_args.bzl b/cc/toolchains/impl/nested_args.bzl
new file mode 100644
index 0000000..dda7498
--- /dev/null
+++ b/cc/toolchains/impl/nested_args.bzl
@@ -0,0 +1,265 @@
+# Copyright 2024 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.
+"""Helper functions for working with args."""
+
+load("//cc:cc_toolchain_config_lib.bzl", "flag_group", "variable_with_value")
+load("//cc/toolchains:cc_toolchain_info.bzl", "NestedArgsInfo")
+
+visibility([
+ "//cc/toolchains",
+ "//tests/rule_based_toolchain/...",
+])
+
+REQUIRES_MUTUALLY_EXCLUSIVE_ERR = "requires_none, requires_not_none, requires_true, requires_false, and requires_equal are mutually exclusive"
+REQUIRES_NOT_NONE_ERR = "requires_not_none only works on options"
+REQUIRES_NONE_ERR = "requires_none only works on options"
+REQUIRES_TRUE_ERR = "requires_true only works on bools"
+REQUIRES_FALSE_ERR = "requires_false only works on bools"
+REQUIRES_EQUAL_ERR = "requires_equal only works on strings"
+REQUIRES_EQUAL_VALUE_ERR = "When requires_equal is provided, you must also provide requires_equal_value to specify what it should be equal to"
+FORMAT_ARGS_ERR = "format_args can only format strings, files, or directories"
+
+_NOT_ESCAPED_FMT = "%% should always either of the form %%s, or escaped with %%%%. Instead, got %r"
+
+_EXAMPLE = """
+
+cc_args(
+ ...,
+ args = [format_arg("--foo=%s", "//cc/toolchains/variables:foo")]
+)
+
+or
+
+cc_args(
+ ...,
+ # If foo_list contains ["a", "b"], then this expands to ["--foo", "+a", "--foo", "+b"].
+ args = ["--foo", format_arg("+%s")],
+ iterate_over = "//toolchains/variables:foo_list",
+"""
+
+def raw_string(s):
+ """Constructs metadata for creating a raw string.
+
+ Args:
+ s: (str) The string to input.
+ Returns:
+ Metadata suitable for format_variable.
+ """
+ return struct(format_type = "raw", format = s)
+
+def format_string_indexes(s, fail = fail):
+ """Gets the index of a '%s' in a string.
+
+ Args:
+ s: (str) The string
+ fail: The fail function. Used for tests
+
+ Returns:
+ List[int] The indexes of the '%s' in the string
+ """
+ indexes = []
+ escaped = False
+ for i in range(len(s)):
+ if not escaped and s[i] == "%":
+ escaped = True
+ elif escaped:
+ if s[i] == "{":
+ fail('Using the old mechanism for variables, %%{variable}, but we instead use format_arg("--foo=%%s", "//cc/toolchains/variables:<variable>"). Got %r' % s)
+ elif s[i] == "s":
+ indexes.append(i - 1)
+ elif s[i] != "%":
+ fail(_NOT_ESCAPED_FMT % s)
+ escaped = False
+ if escaped:
+ return fail(_NOT_ESCAPED_FMT % s)
+ return indexes
+
+def format_variable(arg, iterate_over, fail = fail):
+ """Lists all of the variables referenced by an argument.
+
+ Eg: referenced_variables([
+ format_arg("--foo", None),
+ format_arg("--bar=%s", ":bar")
+ ]) => ["--foo", "--bar=%{bar}"]
+
+ Args:
+ arg: [Formatted] The command-line arguments, as created by the format_arg function.
+ iterate_over: (Optional[str]) The name of the variable we're iterating over.
+ fail: The fail function. Used for tests
+
+ Returns:
+ A string defined to be compatible with flag groups.
+ """
+ indexes = format_string_indexes(arg.format, fail = fail)
+ if arg.format_type == "raw":
+ if indexes:
+ return fail("Can't use %s with a raw string. Either escape it with %%s or use format_arg, like the following examples:" + _EXAMPLE)
+ return arg.format
+ else:
+ if len(indexes) == 0:
+ return fail('format_arg requires a "%%s" in the format string, but got %r' % arg.format)
+ elif len(indexes) > 1:
+ return fail("Only one %%s can be used in a format string, but got %r" % arg.format)
+
+ if arg.value == None:
+ if iterate_over == None:
+ return fail("format_arg requires either a variable to format, or iterate_over must be provided. For example:" + _EXAMPLE)
+ var = iterate_over
+ else:
+ var = arg.value.name
+
+ index = indexes[0]
+ return arg.format[:index] + "%{" + var + "}" + arg.format[index + 2:]
+
+def nested_args_provider(
+ *,
+ label,
+ args = [],
+ nested = [],
+ files = depset([]),
+ iterate_over = None,
+ requires_not_none = None,
+ requires_none = None,
+ requires_true = None,
+ requires_false = None,
+ requires_equal = None,
+ requires_equal_value = "",
+ fail = fail):
+ """Creates a validated NestedArgsInfo.
+
+ Does not validate types, as you can't know the type of a variable until
+ you have a cc_args wrapping it, because the outer layers can change that
+ type using iterate_over.
+
+ Args:
+ label: (Label) The context we are currently evaluating in. Used for
+ error messages.
+ args: (List[str]) The command-line arguments to add.
+ nested: (List[NestedArgsInfo]) command-line arguments to expand.
+ files: (depset[File]) Files required for this set of command-line args.
+ iterate_over: (Optional[str]) Variable to iterate over
+ requires_not_none: (Optional[str]) If provided, this NestedArgsInfo will
+ be ignored if the variable is None
+ requires_none: (Optional[str]) If provided, this NestedArgsInfo will
+ be ignored if the variable is not None
+ requires_true: (Optional[str]) If provided, this NestedArgsInfo will
+ be ignored if the variable is false
+ requires_false: (Optional[str]) If provided, this NestedArgsInfo will
+ be ignored if the variable is true
+ requires_equal: (Optional[str]) If provided, this NestedArgsInfo will
+ be ignored if the variable is not equal to requires_equal_value.
+ requires_equal_value: (str) The value to compare the requires_equal
+ variable with
+ fail: A fail function. Use only for testing.
+ Returns:
+ NestedArgsInfo
+ """
+ if bool(args) == bool(nested):
+ fail("Exactly one of args and nested must be provided")
+
+ transitive_files = [ea.files for ea in nested]
+ transitive_files.append(files)
+
+ has_value = [attr for attr in [
+ requires_not_none,
+ requires_none,
+ requires_true,
+ requires_false,
+ requires_equal,
+ ] if attr != None]
+
+ # We may want to reconsider this down the line, but it's easier to open up
+ # an API than to lock down an API.
+ if len(has_value) > 1:
+ fail(REQUIRES_MUTUALLY_EXCLUSIVE_ERR)
+
+ kwargs = {}
+ requires_types = {}
+ if nested:
+ kwargs["flag_groups"] = [ea.legacy_flag_group for ea in nested]
+
+ unwrap_options = []
+
+ if iterate_over:
+ kwargs["iterate_over"] = iterate_over
+
+ if requires_not_none:
+ kwargs["expand_if_available"] = requires_not_none
+ requires_types.setdefault(requires_not_none, []).append(struct(
+ msg = REQUIRES_NOT_NONE_ERR,
+ valid_types = ["option"],
+ after_option_unwrap = False,
+ ))
+ unwrap_options.append(requires_not_none)
+ elif requires_none:
+ kwargs["expand_if_not_available"] = requires_none
+ requires_types.setdefault(requires_none, []).append(struct(
+ msg = REQUIRES_NONE_ERR,
+ valid_types = ["option"],
+ after_option_unwrap = False,
+ ))
+ elif requires_true:
+ kwargs["expand_if_true"] = requires_true
+ requires_types.setdefault(requires_true, []).append(struct(
+ msg = REQUIRES_TRUE_ERR,
+ valid_types = ["bool"],
+ after_option_unwrap = True,
+ ))
+ unwrap_options.append(requires_true)
+ elif requires_false:
+ kwargs["expand_if_false"] = requires_false
+ requires_types.setdefault(requires_false, []).append(struct(
+ msg = REQUIRES_FALSE_ERR,
+ valid_types = ["bool"],
+ after_option_unwrap = True,
+ ))
+ unwrap_options.append(requires_false)
+ elif requires_equal:
+ if not requires_equal_value:
+ fail(REQUIRES_EQUAL_VALUE_ERR)
+ kwargs["expand_if_equal"] = variable_with_value(
+ name = requires_equal,
+ value = requires_equal_value,
+ )
+ unwrap_options.append(requires_equal)
+ requires_types.setdefault(requires_equal, []).append(struct(
+ msg = REQUIRES_EQUAL_ERR,
+ valid_types = ["string"],
+ after_option_unwrap = True,
+ ))
+
+ for arg in args:
+ if arg.format_type != "raw":
+ var_name = arg.value.name if arg.value != None else iterate_over
+ requires_types.setdefault(var_name, []).append(struct(
+ msg = FORMAT_ARGS_ERR,
+ valid_types = ["string", "file", "directory"],
+ after_option_unwrap = True,
+ ))
+
+ if args:
+ kwargs["flags"] = [
+ format_variable(arg, iterate_over = iterate_over, fail = fail)
+ for arg in args
+ ]
+
+ return NestedArgsInfo(
+ label = label,
+ nested = nested,
+ files = depset(transitive = transitive_files),
+ iterate_over = iterate_over,
+ unwrap_options = unwrap_options,
+ requires_types = requires_types,
+ legacy_flag_group = flag_group(**kwargs),
+ )
diff --git a/tests/rule_based_toolchain/nested_args/BUILD b/tests/rule_based_toolchain/nested_args/BUILD
new file mode 100644
index 0000000..30e75ed
--- /dev/null
+++ b/tests/rule_based_toolchain/nested_args/BUILD
@@ -0,0 +1,14 @@
+load("//cc/toolchains/impl:variables.bzl", "cc_variable", "types")
+load("//tests/rule_based_toolchain:analysis_test_suite.bzl", "analysis_test_suite")
+load(":nested_args_test.bzl", "TARGETS", "TESTS")
+
+cc_variable(
+ name = "foo",
+ type = types.string,
+)
+
+analysis_test_suite(
+ name = "test_suite",
+ targets = TARGETS,
+ tests = TESTS,
+)
diff --git a/tests/rule_based_toolchain/nested_args/nested_args_test.bzl b/tests/rule_based_toolchain/nested_args/nested_args_test.bzl
new file mode 100644
index 0000000..96a361c
--- /dev/null
+++ b/tests/rule_based_toolchain/nested_args/nested_args_test.bzl
@@ -0,0 +1,205 @@
+# Copyright 2024 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.
+"""Tests for the cc_args rule."""
+
+load("//cc:cc_toolchain_config_lib.bzl", "flag_group", "variable_with_value")
+load("//cc/toolchains:cc_toolchain_info.bzl", "VariableInfo")
+load("//cc/toolchains:format.bzl", "format_arg")
+load(
+ "//cc/toolchains/impl:nested_args.bzl",
+ "FORMAT_ARGS_ERR",
+ "REQUIRES_EQUAL_ERR",
+ "REQUIRES_MUTUALLY_EXCLUSIVE_ERR",
+ "REQUIRES_NONE_ERR",
+ "format_string_indexes",
+ "format_variable",
+ "nested_args_provider",
+ "raw_string",
+)
+load("//tests/rule_based_toolchain:subjects.bzl", "result_fn_wrapper", "subjects")
+
+visibility("private")
+
+def _expect_that_nested(env, expr = None, **kwargs):
+ return env.expect.that_value(
+ expr = expr,
+ value = result_fn_wrapper(nested_args_provider)(
+ label = Label("//:args"),
+ **kwargs
+ ),
+ factory = subjects.result(subjects.NestedArgsInfo),
+ )
+
+def _expect_that_formatted(env, var, iterate_over = None, expr = None):
+ return env.expect.that_value(
+ result_fn_wrapper(format_variable)(var, iterate_over),
+ factory = subjects.result(subjects.str),
+ expr = expr or "format_variable(var=%r, iterate_over=%r" % (var, iterate_over),
+ )
+
+def _expect_that_format_string_indexes(env, var, expr = None):
+ return env.expect.that_value(
+ result_fn_wrapper(format_string_indexes)(var),
+ factory = subjects.result(subjects.collection),
+ expr = expr or "format_string_indexes(%r)" % var,
+ )
+
+def _format_string_indexes_test(env, _):
+ _expect_that_format_string_indexes(env, "foo").ok().contains_exactly([])
+ _expect_that_format_string_indexes(env, "%%").ok().contains_exactly([])
+ _expect_that_format_string_indexes(env, "%").err().equals(
+ '% should always either of the form %s, or escaped with %%. Instead, got "%"',
+ )
+ _expect_that_format_string_indexes(env, "%a").err().equals(
+ '% should always either of the form %s, or escaped with %%. Instead, got "%a"',
+ )
+ _expect_that_format_string_indexes(env, "%s").ok().contains_exactly([0])
+ _expect_that_format_string_indexes(env, "%%%s%s").ok().contains_exactly([2, 4])
+ _expect_that_format_string_indexes(env, "%%{").ok().contains_exactly([])
+ _expect_that_format_string_indexes(env, "%%s").ok().contains_exactly([])
+ _expect_that_format_string_indexes(env, "%{foo}").err().equals(
+ 'Using the old mechanism for variables, %{variable}, but we instead use format_arg("--foo=%s", "//cc/toolchains/variables:<variable>"). Got "%{foo}"',
+ )
+
+def _formats_raw_strings_test(env, _):
+ _expect_that_formatted(
+ env,
+ raw_string("foo"),
+ ).ok().equals("foo")
+ _expect_that_formatted(
+ env,
+ raw_string("%s"),
+ ).err().contains("Can't use %s with a raw string. Either escape it with %%s or use format_arg")
+
+def _formats_variables_test(env, targets):
+ _expect_that_formatted(
+ env,
+ format_arg("ab %s cd", targets.foo[VariableInfo]),
+ ).ok().equals("ab %{foo} cd")
+
+ _expect_that_formatted(
+ env,
+ format_arg("foo", targets.foo[VariableInfo]),
+ ).err().equals('format_arg requires a "%s" in the format string, but got "foo"')
+ _expect_that_formatted(
+ env,
+ format_arg("%s%s", targets.foo[VariableInfo]),
+ ).err().equals('Only one %s can be used in a format string, but got "%s%s"')
+
+ _expect_that_formatted(
+ env,
+ format_arg("%s"),
+ iterate_over = "foo",
+ ).ok().equals("%{foo}")
+ _expect_that_formatted(
+ env,
+ format_arg("%s"),
+ ).err().contains("format_arg requires either a variable to format, or iterate_over must be provided")
+
+def _iterate_over_test(env, _):
+ inner = _expect_that_nested(
+ env,
+ args = [raw_string("--foo")],
+ ).ok().actual
+ env.expect.that_str(inner.legacy_flag_group).equals(flag_group(flags = ["--foo"]))
+
+ nested = _expect_that_nested(
+ env,
+ nested = [inner],
+ iterate_over = "my_list",
+ ).ok()
+ nested.iterate_over().some().equals("my_list")
+ nested.legacy_flag_group().equals(flag_group(
+ iterate_over = "my_list",
+ flag_groups = [inner.legacy_flag_group],
+ ))
+ nested.requires_types().contains_exactly({})
+
+def _requires_types_test(env, targets):
+ _expect_that_nested(
+ env,
+ requires_not_none = "abc",
+ requires_none = "def",
+ args = [raw_string("--foo")],
+ expr = "mutually_exclusive",
+ ).err().equals(REQUIRES_MUTUALLY_EXCLUSIVE_ERR)
+
+ _expect_that_nested(
+ env,
+ requires_none = "var",
+ args = [raw_string("--foo")],
+ expr = "requires_none",
+ ).ok().requires_types().contains_exactly(
+ {"var": [struct(
+ msg = REQUIRES_NONE_ERR,
+ valid_types = ["option"],
+ after_option_unwrap = False,
+ )]},
+ )
+
+ _expect_that_nested(
+ env,
+ args = [raw_string("foo %s baz")],
+ expr = "no_variable",
+ ).err().contains("Can't use %s with a raw string")
+
+ _expect_that_nested(
+ env,
+ args = [format_arg("foo %s baz", targets.foo[VariableInfo])],
+ expr = "type_validation",
+ ).ok().requires_types().contains_exactly(
+ {"foo": [struct(
+ msg = FORMAT_ARGS_ERR,
+ valid_types = ["string", "file", "directory"],
+ after_option_unwrap = True,
+ )]},
+ )
+
+ nested = _expect_that_nested(
+ env,
+ requires_equal = "foo",
+ requires_equal_value = "value",
+ args = [format_arg("--foo=%s", targets.foo[VariableInfo])],
+ expr = "type_and_requires_equal_validation",
+ ).ok()
+ nested.requires_types().contains_exactly(
+ {"foo": [
+ struct(
+ msg = REQUIRES_EQUAL_ERR,
+ valid_types = ["string"],
+ after_option_unwrap = True,
+ ),
+ struct(
+ msg = FORMAT_ARGS_ERR,
+ valid_types = ["string", "file", "directory"],
+ after_option_unwrap = True,
+ ),
+ ]},
+ )
+ nested.legacy_flag_group().equals(flag_group(
+ expand_if_equal = variable_with_value(name = "foo", value = "value"),
+ flags = ["--foo=%{foo}"],
+ ))
+
+TARGETS = [
+ ":foo",
+]
+
+TESTS = {
+ "format_string_indexes_test": _format_string_indexes_test,
+ "formats_raw_strings_test": _formats_raw_strings_test,
+ "formats_variables_test": _formats_variables_test,
+ "iterate_over_test": _iterate_over_test,
+ "requires_types_test": _requires_types_test,
+}
diff --git a/tests/rule_based_toolchain/subjects.bzl b/tests/rule_based_toolchain/subjects.bzl
index 628996e..f42d5d7 100644
--- a/tests/rule_based_toolchain/subjects.bzl
+++ b/tests/rule_based_toolchain/subjects.bzl
@@ -112,6 +112,7 @@
iterate_over = optional_subject(_subjects.str),
legacy_flag_group = unknown_subject,
requires_types = _subjects.dict,
+ unwrap_options = _subjects.collection,
)
# buildifier: disable=name-conventions
