install_*: FileMode doesn't need to be None

There's no reason to allow None into the backend, it already has code to
check that all of the values of the FileMode object are None, so let's
use that, which is much simpler all the way down.

1 files changed, 1 insertions, 3 deletions

diff --git a/mesonbuild/interpreter/interpreter.py b/mesonbuild/interpreter/interpreter.py
index d522d25..8d1b693 100644
--- a/mesonbuild/interpreter/interpreter.py
+++ b/mesonbuild/interpreter/interpreter.py
@@ -128,7 +128,7 @@ def _install_mode_validator(mode: T.List[T.Union[str, bool, int]]) -> T.Optional
     return None
 
 
-def _install_mode_convertor(mode: T.Optional[T.List[T.Union[str, bool, int]]]) -> T.Optional[FileMode]:
+def _install_mode_convertor(mode: T.Optional[T.List[T.Union[str, bool, int]]]) -> FileMode:
     """Convert the DSL form of the `install_mode` keyword arugment to `FileMode`
 
     This is not required, and if not required returns None
@@ -136,8 +136,6 @@ def _install_mode_convertor(mode: T.Optional[T.List[T.Union[str, bool, int]]]) -
     TODO: It's not clear to me why this needs to be None and not just return an
     emtpy FileMode.
     """
-    if mode is None:
-        return None
     # this has already been validated by the validator
     return FileMode(*[m if isinstance(m, str) else None for m in mode])