Refactor subdir visitation to track files instead of dirs.

1 files changed, 4 insertions, 3 deletions

diff --git a/mesonbuild/interpreter.py b/mesonbuild/interpreter.py
index c8cf078..68744ef 100644
--- a/mesonbuild/interpreter.py
+++ b/mesonbuild/interpreter.py
@@ -2380,7 +2380,7 @@ class Interpreter(InterpreterBase):
             self.sanity_check_ast()
         self.builtin.update({'meson': MesonMain(build, self)})
         self.generators = []
-        self.visited_subdirs = {}
+        self.processed_buildfiles = set() # type: T.Set[str]
         self.project_args_frozen = False
         self.global_args_frozen = False  # implies self.project_args_frozen
         self.subprojects = {}
@@ -4212,10 +4212,11 @@ This will become a hard error in the future.''' % kwargs['input'], location=self
             raise InvalidArguments('Subdir argument must be a relative path.')
         absdir = os.path.join(self.environment.get_source_dir(), subdir)
         symlinkless_dir = os.path.realpath(absdir)
-        if symlinkless_dir in self.visited_subdirs:
+        build_file = os.path.join(symlinkless_dir, 'meson.build')
+        if build_file in self.processed_buildfiles:
             raise InvalidArguments('Tried to enter directory "%s", which has already been visited.'
                                    % subdir)
-        self.visited_subdirs[symlinkless_dir] = True
+        self.processed_buildfiles.add(build_file)
         self.subdir = subdir
         os.makedirs(os.path.join(self.environment.build_dir, subdir), exist_ok=True)
         buildfilename = os.path.join(self.subdir, environment.build_filename)