raw string literals are next to godliness

Invalid escape sequences are deprecated and will be removed from a
future version of python. Use r"" to define them so they remain
readable.

mesonbuild/compilers/cuda.py

@@ -186,7 +186,7 @@ class CudaCompiler(Compiler):
 
     @classmethod
     def _shield_nvcc_list_arg(cls, arg: str, listmode: bool=True) -> str:
-        """
+        r"""
         Shield an argument against both splitting by NVCC's list-argument
         parse logic, and interpretation by any shell.
 
@@ -256,7 +256,7 @@ class CudaCompiler(Compiler):
             # Shield individual strings, without listmode, then return them with
             # escaped commas between them.
             l = [cls._shield_nvcc_list_arg(s, listmode=False) for s in l]
-            return '\,'.join(l)
+            return r'\,'.join(l)
 
     @classmethod
     def _to_host_flags(cls, flags: T.List[str], phase: _Phase = _Phase.COMPILER) -> T.List[str]:

mesonbuild/mcompile.py

@@ -175,7 +175,7 @@ def generate_target_name_vs(target: ParsedTargetName, builddir: Path, introspect
 
     # Normalize project name
     # Source: https://docs.microsoft.com/en-us/visualstudio/msbuild/how-to-build-specific-targets-in-solutions-by-using-msbuild-exe
-    target_name = re.sub('[\%\$\@\;\.\(\)\']', '_', intro_target['id'])  # type: str
+    target_name = re.sub(r"[\%\$\@\;\.\(\)']", '_', intro_target['id'])  # type: str
     rel_path = Path(intro_target['filename'][0]).relative_to(builddir.resolve()).parent
     if rel_path != Path('.'):
         target_name = str(rel_path / target_name)

mesonbuild/scripts/depscan.py

@@ -22,8 +22,8 @@ import typing as T
 from ..backend.ninjabackend import TargetDependencyScannerInfo, ninja_quote
 from ..compilers.compilers import lang_suffixes
 
-CPP_IMPORT_RE = re.compile('\w*import ([a-zA-Z0-9]+);')
+CPP_IMPORT_RE = re.compile(r'\w*import ([a-zA-Z0-9]+);')
-CPP_EXPORT_RE = re.compile('\w*export module ([a-zA-Z0-9]+);')
+CPP_EXPORT_RE = re.compile(r'\w*export module ([a-zA-Z0-9]+);')
 
 FORTRAN_INCLUDE_PAT = r"^\s*include\s*['\"](\w+\.\w+)['\"]"
 FORTRAN_MODULE_PAT = r"^\s*\bmodule\b\s+(\w+)\s*(?:!+.*)*$"

run_unittests.py

@@ -5893,7 +5893,7 @@ class FailureTests(BasePlatformTests):
 
     def test_error_func(self):
         self.assertMesonRaises("error('a', 'b', ['c', ['d', {'e': 'f'}]], 'g')",
-                               "Problem encountered: a b \['c', \['d', {'e' : 'f'}\]\] g")
+                               r"Problem encountered: a b \['c', \['d', {'e' : 'f'}\]\] g")
 
 
 @unittest.skipUnless(is_windows() or is_cygwin(), "requires Windows (or Windows via Cygwin)")