typing: get rid of most T.cast

mesonbuild/arglist.py

@@ -242,7 +242,7 @@ class CompilerArgs(collections.abc.MutableSequence):
             new = self.copy()
         else:
             new = self
-        return T.cast(T.List[str], self.compiler.unix_args_to_native(new._container))
+        return self.compiler.unix_args_to_native(new._container)
 
     def append_direct(self, arg: str) -> None:
         '''

mesonbuild/compilers/compilers.py

@@ -578,7 +578,7 @@ class Compiler(metaclass=abc.ABCMeta):
         raise EnvironmentException('Language %s does not support function checks.' % self.get_display_language())
 
     @classmethod
-    def unix_args_to_native(cls, args):
+    def unix_args_to_native(cls, args: T.List[str]) -> T.List[str]:
         "Always returns a copy that can be independently mutated"
         return args[:]
 

mesonbuild/coredata.py

@@ -365,7 +365,7 @@ _V = T.TypeVar('_V')
 
 class CoreData:
 
-    def __init__(self, options: argparse.Namespace, scratch_dir: str):
+    def __init__(self, options: argparse.Namespace, scratch_dir: str, meson_command: T.List[str]):
         self.lang_guids = {
             'default': '8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942',
             'c': '8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942',
@@ -376,6 +376,7 @@ class CoreData:
         self.test_guid = str(uuid.uuid4()).upper()
         self.regen_guid = str(uuid.uuid4()).upper()
         self.install_guid = str(uuid.uuid4()).upper()
+        self.meson_command = meson_command
         self.target_guids = {}
         self.version = version
         self.builtins = {} # type: OptionDictType

mesonbuild/environment.py

@@ -814,9 +814,8 @@ class Environment:
         # WARNING: Don't use any values from coredata in __init__. It gets
         # re-initialized with project options by the interpreter during
         # build file parsing.
-        self.coredata = coredata.CoreData(options, self.scratch_dir)
-        # Used by the regenchecker script, which runs meson
-        self.coredata.meson_command = mesonlib.meson_command
+        # meson_command is used by the regenchecker script, which runs meson
+        self.coredata = coredata.CoreData(options, self.scratch_dir, mesonlib.meson_command)
         self.first_invocation = True
 
     def is_cross_build(self, when_building_for: MachineChoice = MachineChoice.HOST) -> bool:
@@ -1038,7 +1037,7 @@ class Environment:
         :extra_args: Any additional arguments required (such as a source file)
         """
         self.coredata.add_lang_args(comp_class.language, comp_class, for_machine, self)
-        extra_args = T.cast(T.List[str], extra_args or [])
+        extra_args = extra_args or []
         extra_args += self.coredata.compiler_options[for_machine][comp_class.language]['args'].value
 
         if isinstance(comp_class.LINKER_PREFIX, str):

mesonbuild/interpreterbase.py

@@ -879,6 +879,7 @@ The result of this is undefined and will become a hard error in a future Meson r
             if not isinstance(index, str):
                 raise InterpreterException('Key is not a string')
             try:
+                # The cast is required because we don't have recursive types...
                 return T.cast(TYPE_var, iobject[index])
             except KeyError:
                 raise InterpreterException('Key %s is not in dict' % index)
@@ -1091,7 +1092,7 @@ The result of this is undefined and will become a hard error in a future Meson r
         raise InvalidCode('Unknown function "%s".' % func_name)
 
     @builtinMethodNoKwargs
-    def array_method_call(self, obj: list, method_name: str, posargs: T.List[TYPE_nvar], kwargs: T.Dict[str, T.Any]) -> TYPE_var:
+    def array_method_call(self, obj: T.List[TYPE_var], method_name: str, posargs: T.List[TYPE_nvar], kwargs: T.Dict[str, T.Any]) -> TYPE_var:
         if method_name == 'contains':
             def check_contains(el: list) -> bool:
                 if len(posargs) != 1:
@@ -1127,7 +1128,7 @@ The result of this is undefined and will become a hard error in a future Meson r
                 if isinstance(fallback, mparser.BaseNode):
                     return self.evaluate_statement(fallback)
                 return fallback
-            return T.cast(TYPE_var, obj[index])
+            return obj[index]
         m = 'Arrays do not have a method called {!r}.'
         raise InterpreterException(m.format(method_name))
 

mesonbuild/scripts/regen_checker.py

@@ -15,13 +15,12 @@
 import sys, os
 import pickle, subprocess
 import typing as T
-
-if T.TYPE_CHECKING:
-    from ..backend.vs2010backend import RegenInfo
+from ..coredata import CoreData
+from ..backend.vs2010backend import RegenInfo
 
 # This could also be used for XCode.
 
-def need_regen(regeninfo: 'RegenInfo', regen_timestamp: float) -> bool:
+def need_regen(regeninfo: RegenInfo, regen_timestamp: float) -> bool:
     for i in regeninfo.depfiles:
         curfile = os.path.join(regeninfo.build_dir, i)
         curtime = os.stat(curfile).st_mtime
@@ -35,7 +34,7 @@ def need_regen(regeninfo: 'RegenInfo', regen_timestamp: float) -> bool:
     Vs2010Backend.touch_regen_timestamp(regeninfo.build_dir)
     return False
 
-def regen(regeninfo: 'RegenInfo', meson_command: T.List[str], backend: str) -> None:
+def regen(regeninfo: RegenInfo, meson_command: T.List[str], backend: str) -> None:
     cmd = meson_command + ['--internal',
                            'regenerate',
                            regeninfo.build_dir,
@@ -48,10 +47,13 @@ def run(args: T.List[str]) -> int:
     dumpfile = os.path.join(private_dir, 'regeninfo.dump')
     coredata_file = os.path.join(private_dir, 'coredata.dat')
     with open(dumpfile, 'rb') as f:
-        regeninfo = T.cast('RegenInfo', pickle.load(f))
+        regeninfo = pickle.load(f)
+        assert isinstance(regeninfo, RegenInfo)
     with open(coredata_file, 'rb') as f:
         coredata = pickle.load(f)
+        assert isinstance(coredata, CoreData)
     backend = coredata.get_builtin_option('backend')
+    assert isinstance(backend, str)
     regen_timestamp = os.stat(dumpfile).st_mtime
     if need_regen(regeninfo, regen_timestamp):
         regen(regeninfo, coredata.meson_command, backend)

mesonbuild/scripts/tags.py

@@ -48,4 +48,6 @@ def run(args: T.List[str]) -> int:
     srcdir_name = args[1]
     os.chdir(srcdir_name)
     assert tool_name in ['cscope', 'ctags', 'etags']
-    return T.cast(int, globals()[tool_name]())
+    res = globals()[tool_name]()
+    assert isinstance(res, int)
+    return res