bazel_to_cmake: improve make variable substitution, debugging.

Allow make variables to contain nested ().

PiperOrigin-RevId: 586910026
Change-Id: I70d4654e5d0cf89c33d510beda786deec960211b

tools/cmake/bazel_to_cmake/evaluation.py

@@ -118,7 +118,8 @@
 
 
 class RuleInfo(NamedTuple):
-  mnemonic: Optional[str]  # Only used for debugging currently.
+  mnemonic: str  # Only used for debugging currently.
+  callers: List[str]
   outs: List[TargetId]
   impl: RuleImpl
 
@@ -129,18 +130,6 @@ class Phase(enum.Enum):
   ANALYZE = 3
 
 
-def _get_mnemonic(currentframe) -> Optional[str]:
-  """Returns a mnemonic from currentframe."""
-  if not currentframe:
-    return None
-  # pytype: disable=attribute-error
-  kind = currentframe.f_back.f_back.f_code.co_name
-  # pytype: enable=attribute-error
-  if kind.startswith("bazel_"):
-    kind = kind[len("bazel_") :]
-  return kind
-
-
 class EvaluationState:
   """State used while evaluating Starlark code."""
 
@@ -220,6 +209,8 @@ def analyze(self, targets: List[TargetId]):
 
   def add_rule(
       self,
+      _mnemonic: str,
+      _callers: List[str],
       rule_id: TargetId,
       impl: RuleImpl,
       outs: Optional[List[TargetId]] = None,
@@ -239,11 +230,8 @@ def add_rule(
       raise ValueError(f"Duplicate rule: {rule_id.as_label()}")
     if outs is None:
       outs = []
-
     # kind is assigned from caller function name
-    currentframe = inspect.currentframe()
-    r = RuleInfo(mnemonic=_get_mnemonic(currentframe), outs=outs, impl=impl)
-    del currentframe
+    r = RuleInfo(_mnemonic, _callers, outs=outs, impl=impl)
     self._all_rules[rule_id] = r
     self._unanalyzed_rules.add(rule_id)
     self._unanalyzed_targets[rule_id] = rule_id
@@ -475,7 +463,7 @@ def get_dep(
         for package in info[CMakePackageDepsProvider].packages:
           self.add_required_dep_package(package)
       if info.get(CMakeDepsProvider):
-        return info[CMakeDepsProvider].targets
+        return info[CMakeDepsProvider].targets.copy()
 
     # If this package is already a required dependency, return that.
     cmake_target = self._required_dep_targets.get(target_id)
@@ -708,7 +696,12 @@ def wrapper(*args, **kwargs):
 class EvaluationContext(InvocationContext):
   """Implements InvocationContext interface for EvaluationState."""
 
-  __slots__ = ("_state", "_caller_package_id", "_caller_package")
+  __slots__ = (
+      "_state",
+      "_caller_package_id",
+      "_caller_package",
+      "_rule_location",
+  )
 
   def __init__(
       self,
@@ -720,6 +713,7 @@ def __init__(
     self._state = state
     self._caller_package_id = package_id
     self._caller_package = package
+    self._rule_location = ("<unknown>", list())
     assert self._caller_package_id
 
   def __repr__(self):
@@ -732,6 +726,16 @@ def __repr__(self):
         "}\n"
     )
 
+  def record_rule_location(self, mnemonic):
+    # Record the path of non-python callers.
+    s = inspect.stack()
+    callers = []
+    for i in range(2, min(6, len(s))):
+      c = inspect.getframeinfo(s[i][0])
+      if not c.filename.endswith(".py"):
+        callers.append(f"{c.filename}:{c.lineno}")
+    self._rule_location = (mnemonic, callers)
+
   def update_current_package(
       self,
       package: Optional[Package] = None,
@@ -829,7 +833,15 @@ def add_rule(
         kwargs["analyze_by_default"] = Visibility(
             self._caller_package
         ).analyze_by_default(self.resolve_target_or_label_list(visibility))
-    self._state.add_rule(rule_id, impl, outs, **kwargs)
+
+    self._state.add_rule(
+        self._rule_location[0],
+        self._rule_location[1],
+        rule_id,
+        impl,
+        outs,
+        **kwargs,
+    )
 
   @trace_exception
   def add_analyzed_target(self, target_id: TargetId, info: TargetInfo) -> None:

tools/cmake/bazel_to_cmake/main.py

@@ -87,35 +87,7 @@ def get_bindings_from_args(
   return bindings
 
 
-def main():
-  ap = argparse.ArgumentParser()
-  # Used for top-level project and dependencies.
-  ap.add_argument("--bazel-repo-name", required=True)
-  ap.add_argument("--cmake-project-name", required=True)
-  ap.add_argument("--build-rules-output")
-  ap.add_argument("--cmake-binary-dir")
-  ap.add_argument("--include-package", action="append", default=[])
-  ap.add_argument("--exclude-package", action="append", default=[])
-  ap.add_argument("--repo-mapping", nargs=2, action="append", default=[])
-  ap.add_argument("--extra-build", action="append", default=[])
-  ap.add_argument("--exclude-target", action="append", default=[])
-  ap.add_argument("--bind", action="append", default=[])
-
-  # Used for sub-projects only.
-  ap.add_argument("--load-workspace")
-  ap.add_argument("--target", action="append", default=[])
-
-  # Used for the top-level project only.
-  ap.add_argument("--save-workspace")
-  ap.add_argument("--define", action="append", default=[])
-  ap.add_argument("--ignore-library", action="append", default=[])
-  ap.add_argument("--cmake-vars")
-  ap.add_argument("--bazelrc", action="append", default=[])
-  ap.add_argument("--module", action="append", default=[])
-  ap.add_argument("--verbose", type=int, default=0)
-
-  args = ap.parse_args()
-
+def run_main(args: argparse.Namespace):
   assert args.bazel_repo_name
   repository_id: RepositoryId = RepositoryId(args.bazel_repo_name)
   current_repository: CMakeRepository = CMakeRepository(
@@ -327,3 +299,34 @@ def _persist_cmakepairs(target: TargetId, cmake_pair: CMakeTargetPair):
       pickle.dump(workspace, f)
 
   return 0
+
+
+def main():
+  ap = argparse.ArgumentParser()
+  # Used for top-level project and dependencies.
+  ap.add_argument("--bazel-repo-name", required=True)
+  ap.add_argument("--cmake-project-name", required=True)
+  ap.add_argument("--build-rules-output")
+  ap.add_argument("--cmake-binary-dir")
+  ap.add_argument("--include-package", action="append", default=[])
+  ap.add_argument("--exclude-package", action="append", default=[])
+  ap.add_argument("--repo-mapping", nargs=2, action="append", default=[])
+  ap.add_argument("--extra-build", action="append", default=[])
+  ap.add_argument("--exclude-target", action="append", default=[])
+  ap.add_argument("--bind", action="append", default=[])
+
+  # Used for sub-projects only.
+  ap.add_argument("--load-workspace")
+  ap.add_argument("--target", action="append", default=[])
+
+  # Used for the top-level project only.
+  ap.add_argument("--save-workspace")
+  ap.add_argument("--define", action="append", default=[])
+  ap.add_argument("--ignore-library", action="append", default=[])
+  ap.add_argument("--cmake-vars")
+  ap.add_argument("--bazelrc", action="append", default=[])
+  ap.add_argument("--module", action="append", default=[])
+  ap.add_argument("--verbose", type=int, default=0)
+
+  args = ap.parse_args()
+  return run_main(args)

tools/cmake/bazel_to_cmake/starlark/bazel_globals.py

@@ -28,6 +28,7 @@
 from .select import Select
 from .struct import Struct
 
+
 T = TypeVar("T")
 
 
@@ -158,12 +159,10 @@ def bazel_native(self):
     return BazelNativeBuildRules(self._context)
 
   def bazel_select(self, conditions: Dict[RelativeLabel, T]) -> Select[T]:
-    return Select(
-        {
-            self._context.resolve_target_or_label(condition): value
-            for condition, value in conditions.items()
-        }
-    )
+    return Select({
+        self._context.resolve_target_or_label(condition): value
+        for condition, value in conditions.items()
+    })
 
   bazel_provider = staticmethod(provider)
 
@@ -208,6 +207,7 @@ def register_native_build_rule(impl):
   name = impl.__name__
 
   def wrapper(self, *args, **kwargs):
+    self._context.record_rule_location(name)  # pylint: disable=protected-access
     return impl(self._context, *args, **kwargs)  # pylint: disable=protected-access
 
   setattr(BazelNativeBuildRules, name, wrapper)
@@ -219,6 +219,7 @@ def register_native_workspace_rule(impl):
   name = impl.__name__
 
   def wrapper(self, *args, **kwargs):
+    self._context.record_rule_location(name)  # pylint: disable=protected-access
     return impl(self._context, *args, **kwargs)  # pylint: disable=protected-access
 
   setattr(BazelNativeWorkspaceRules, name, wrapper)

tools/cmake/bazel_to_cmake/starlark/invocation_context.py

@@ -57,6 +57,10 @@ def caller_repository_name(self) -> str:
   def caller_package_id(self) -> PackageId:
     raise NotImplementedError("caller_package_id")
 
+  def record_rule_location(self, mnemonic):
+    # Adds debugging information to registered rules.
+    pass
+
   def workspace_root_for_label(self, repository_id: RepositoryId) -> str:
     # This should return something like the Package.source_directory
     return self.resolve_source_root(repository_id).as_posix()

tools/cmake/bazel_to_cmake/starlark/rule.py

@@ -111,6 +111,47 @@ def impl(ctx: RuleCtx):
 
     return Attr(handle)
 
+  @staticmethod
+  def string_list(
+      mandatory: bool = False,
+      allow_empty: bool = True,
+      *,
+      default: Optional[List[str]] = None,
+      doc: str = "",
+  ):
+    """https://bazel.build/rules/lib/attr#string_list"""
+    del doc
+
+    if default is None:
+      default = []
+
+    def handle(
+        context: InvocationContext,
+        name: str,
+        value: Optional[List[str]],
+        outs: List[TargetId],
+    ):
+      if mandatory and value is None:
+        raise ValueError(f"Attribute {name} not specified")
+      if value is None:
+        value = default
+      if not value and not allow_empty:
+        raise ValueError(f"Attribute {name} is empty")
+
+      del outs
+      del context
+
+      def impl(ctx: RuleCtx):
+        setattr(
+            ctx.attr,
+            name,
+            ctx._context.evaluate_configurable_list(value),
+        )
+
+      return impl
+
+    return Attr(handle)
+
   @staticmethod
   def label(
       default: Optional[Configurable[RelativeLabel]] = None,

tools/cmake/bazel_to_cmake/starlark/rule_test.py

@@ -35,6 +35,7 @@ def _empty_rule_impl(ctx):
     implementation = _empty_rule_impl,
     attrs = {
         "a_string": attr.string(default = "b"),
+        "a_stringlist": attr.string_list(),
         "a_label": attr.label(allow_files = [".header"]),
         "a_labellist": attr.label_list(),
         "a_bool": attr.bool(default = False),