various python neatness cleanups

All changes were created by running

"pyupgrade --py3-only --keep-percent-format"

and committing the results. I have not touched string formatting for
now.

- use set literals
- simplify .format() parameter naming
- remove __future__
- remove default "r" mode for open()
- use OSError rather than compatibility aliases
- remove stray parentheses in function(generator) scopes

45 files changed, 134 insertions, 140 deletions

diff --git a/mesonbuild/backend/backends.py b/mesonbuild/backend/backends.py
index b663736..2e1f081 100644
--- a/mesonbuild/backend/backends.py
+++ b/mesonbuild/backend/backends.py
@@ -505,7 +505,7 @@ class Backend:
         data = bytes(str(es.env) + str(es.cmd_args) + str(es.workdir) + str(capture),
                      encoding='utf-8')
         digest = hashlib.sha1(data).hexdigest()
-        scratch_file = 'meson_exe_{0}_{1}.dat'.format(basename, digest)
+        scratch_file = 'meson_exe_{}_{}.dat'.format(basename, digest)
         exe_data = os.path.join(self.environment.get_scratch_dir(), scratch_file)
         with open(exe_data, 'wb') as f:
             pickle.dump(es, f)
diff --git a/mesonbuild/build.py b/mesonbuild/build.py
index 10d6e3c..77dfdaa 100644
--- a/mesonbuild/build.py
+++ b/mesonbuild/build.py
@@ -43,9 +43,9 @@ if T.TYPE_CHECKING:
     from .mesonlib import FileMode, FileOrString
     from .mesonlib.backend import Backend
 
-pch_kwargs = set(['c_pch', 'cpp_pch'])
+pch_kwargs = {'c_pch', 'cpp_pch'}
 
-lang_arg_kwargs = set([
+lang_arg_kwargs = {
     'c_args',
     'cpp_args',
     'cuda_args',
@@ -61,13 +61,13 @@ lang_arg_kwargs = set([
     'rust_args',
     'vala_args',
     'cs_args',
-])
+}
 
-vala_kwargs = set(['vala_header', 'vala_gir', 'vala_vapi'])
-rust_kwargs = set(['rust_crate_type'])
-cs_kwargs = set(['resources', 'cs_args'])
+vala_kwargs = {'vala_header', 'vala_gir', 'vala_vapi'}
+rust_kwargs = {'rust_crate_type'}
+cs_kwargs = {'resources', 'cs_args'}
 
-buildtarget_kwargs = set([
+buildtarget_kwargs = {
     'build_by_default',
     'build_rpath',
     'dependencies',
@@ -92,7 +92,7 @@ buildtarget_kwargs = set([
     'gnu_symbol_visibility',
     'link_language',
     'win_subsystem',
-])
+}
 
 known_build_target_kwargs = (
     buildtarget_kwargs |
@@ -1723,8 +1723,8 @@ class Executable(BuildTarget):
             if not isinstance(kwargs.get('implib', False), bool):
                 implib_basename = kwargs['implib']
             if m.is_windows() or m.is_cygwin():
-                self.vs_import_filename = '{0}.lib'.format(implib_basename)
-                self.gcc_import_filename = 'lib{0}.a'.format(implib_basename)
+                self.vs_import_filename = '{}.lib'.format(implib_basename)
+                self.gcc_import_filename = 'lib{}.a'.format(implib_basename)
                 if self.get_using_msvc():
                     self.import_filename = self.vs_import_filename
                 else:
@@ -1787,7 +1787,7 @@ class StaticLibrary(BuildTarget):
                 self.rust_crate_type = 'rlib'
             # Don't let configuration proceed with a non-static crate type
             elif self.rust_crate_type not in ['rlib', 'staticlib']:
-                raise InvalidArguments('Crate type "{0}" invalid for static libraries; must be "rlib" or "staticlib"'.format(self.rust_crate_type))
+                raise InvalidArguments('Crate type "{}" invalid for static libraries; must be "rlib" or "staticlib"'.format(self.rust_crate_type))
         # By default a static library is named libfoo.a even on Windows because
         # MSVC does not have a consistent convention for what static libraries
         # are called. The MSVC CRT uses libfoo.lib syntax but nothing else uses
@@ -1828,7 +1828,7 @@ class StaticLibrary(BuildTarget):
             if isinstance(rust_crate_type, str):
                 self.rust_crate_type = rust_crate_type
             else:
-                raise InvalidArguments('Invalid rust_crate_type "{0}": must be a string.'.format(rust_crate_type))
+                raise InvalidArguments('Invalid rust_crate_type "{}": must be a string.'.format(rust_crate_type))
 
     def is_linkable_target(self):
         return True
@@ -1859,7 +1859,7 @@ class SharedLibrary(BuildTarget):
                 self.rust_crate_type = 'dylib'
             # Don't let configuration proceed with a non-dynamic crate type
             elif self.rust_crate_type not in ['dylib', 'cdylib']:
-                raise InvalidArguments('Crate type "{0}" invalid for dynamic libraries; must be "dylib" or "cdylib"'.format(self.rust_crate_type))
+                raise InvalidArguments('Crate type "{}" invalid for dynamic libraries; must be "dylib" or "cdylib"'.format(self.rust_crate_type))
         if not hasattr(self, 'prefix'):
             self.prefix = None
         if not hasattr(self, 'suffix'):
@@ -1919,13 +1919,13 @@ class SharedLibrary(BuildTarget):
         # For all other targets/platforms import_filename stays None
         elif env.machines[self.for_machine].is_windows():
             suffix = 'dll'
-            self.vs_import_filename = '{0}{1}.lib'.format(self.prefix if self.prefix is not None else '', self.name)
-            self.gcc_import_filename = '{0}{1}.dll.a'.format(self.prefix if self.prefix is not None else 'lib', self.name)
+            self.vs_import_filename = '{}{}.lib'.format(self.prefix if self.prefix is not None else '', self.name)
+            self.gcc_import_filename = '{}{}.dll.a'.format(self.prefix if self.prefix is not None else 'lib', self.name)
             if self.uses_rust():
                 # Shared library is of the form foo.dll
                 prefix = ''
                 # Import library is called foo.dll.lib
-                self.import_filename = '{0}.dll.lib'.format(self.name)
+                self.import_filename = '{}.dll.lib'.format(self.name)
                 create_debug_file = True
             elif self.get_using_msvc():
                 # Shared library is of the form foo.dll
@@ -1946,7 +1946,7 @@ class SharedLibrary(BuildTarget):
                 self.filename_tpl = '{0.prefix}{0.name}.{0.suffix}'
         elif env.machines[self.for_machine].is_cygwin():
             suffix = 'dll'
-            self.gcc_import_filename = '{0}{1}.dll.a'.format(self.prefix if self.prefix is not None else 'lib', self.name)
+            self.gcc_import_filename = '{}{}.dll.a'.format(self.prefix if self.prefix is not None else 'lib', self.name)
             # Shared library is of the form cygfoo.dll
             # (ld --dll-search-prefix=cyg is the default)
             prefix = 'cyg'
@@ -2045,7 +2045,7 @@ class SharedLibrary(BuildTarget):
                 if not isinstance(self.ltversion, str):
                     raise InvalidArguments('Shared library version needs to be a string, not ' + type(self.ltversion).__name__)
                 if not re.fullmatch(r'[0-9]+(\.[0-9]+){0,2}', self.ltversion):
-                    raise InvalidArguments('Invalid Shared library version "{0}". Must be of the form X.Y.Z where all three are numbers. Y and Z are optional.'.format(self.ltversion))
+                    raise InvalidArguments('Invalid Shared library version "{}". Must be of the form X.Y.Z where all three are numbers. Y and Z are optional.'.format(self.ltversion))
             # Try to extract/deduce the soversion
             if 'soversion' in kwargs:
                 self.soversion = kwargs['soversion']
@@ -2092,7 +2092,7 @@ class SharedLibrary(BuildTarget):
             if isinstance(rust_crate_type, str):
                 self.rust_crate_type = rust_crate_type
             else:
-                raise InvalidArguments('Invalid rust_crate_type "{0}": must be a string.'.format(rust_crate_type))
+                raise InvalidArguments('Invalid rust_crate_type "{}": must be a string.'.format(rust_crate_type))
 
     def get_import_filename(self):
         """
@@ -2199,7 +2199,7 @@ class CommandBase:
         return final_cmd
 
 class CustomTarget(Target, CommandBase):
-    known_kwargs = set([
+    known_kwargs = {
         'input',
         'output',
         'command',
@@ -2216,7 +2216,7 @@ class CustomTarget(Target, CommandBase):
         'override_options',
         'console',
         'env',
-    ])
+    }
 
     def __init__(self, name: str, subdir: str, subproject: str, kwargs: T.Dict[str, T.Any],
                  absolute_paths: bool = False, backend: T.Optional['Backend'] = None):
diff --git a/mesonbuild/compilers/compilers.py b/mesonbuild/compilers/compilers.py
index a37e4da..56c97f4 100644
--- a/mesonbuild/compilers/compilers.py
+++ b/mesonbuild/compilers/compilers.py
@@ -762,7 +762,7 @@ class Compiler(metaclass=abc.ABCMeta):
                 contents = code
             elif isinstance(code, mesonlib.File):
                 srcname = code.fname
-                with open(code.fname, 'r') as f:
+                with open(code.fname) as f:
                     contents = f.read()
 
             # Construct the compiler command-line
@@ -1009,16 +1009,16 @@ class Compiler(metaclass=abc.ABCMeta):
         return []
 
     def get_crt_compile_args(self, crt_val: str, buildtype: str) -> T.List[str]:
-        raise EnvironmentError('This compiler does not support Windows CRT selection')
+        raise OSError('This compiler does not support Windows CRT selection')
 
     def get_crt_link_args(self, crt_val: str, buildtype: str) -> T.List[str]:
-        raise EnvironmentError('This compiler does not support Windows CRT selection')
+        raise OSError('This compiler does not support Windows CRT selection')
 
     def get_compile_only_args(self) -> T.List[str]:
         return []
 
     def get_preprocess_only_args(self) -> T.List[str]:
-        raise EnvironmentError('This compiler does not have a preprocessor')
+        raise OSError('This compiler does not have a preprocessor')
 
     def get_default_include_dirs(self) -> T.List[str]:
         return []
@@ -1095,7 +1095,7 @@ class Compiler(metaclass=abc.ABCMeta):
         return objfile + '.' + self.get_depfile_suffix()
 
     def get_depfile_suffix(self) -> str:
-        raise EnvironmentError('{} does not implement get_depfile_suffix'.format(self.id))
+        raise OSError('{} does not implement get_depfile_suffix'.format(self.id))
 
     def get_no_stdinc_args(self) -> T.List[str]:
         """Arguments to turn off default inclusion of standard libraries."""
@@ -1112,13 +1112,13 @@ class Compiler(metaclass=abc.ABCMeta):
         pass
 
     def get_module_incdir_args(self) -> T.Tuple[str, ...]:
-        raise EnvironmentError('{} does not implement get_module_incdir_args'.format(self.id))
+        raise OSError('{} does not implement get_module_incdir_args'.format(self.id))
 
     def get_module_outdir_args(self, path: str) -> T.List[str]:
-        raise EnvironmentError('{} does not implement get_module_outdir_args'.format(self.id))
+        raise OSError('{} does not implement get_module_outdir_args'.format(self.id))
 
     def module_name_to_filename(self, module_name: str) -> str:
-        raise EnvironmentError('{} does not implement module_name_to_filename'.format(self.id))
+        raise OSError('{} does not implement module_name_to_filename'.format(self.id))
 
     def get_compiler_check_args(self, mode: CompileCheckMode) -> T.List[str]:
         """Arguments to pass the compiler and/or linker for checks.
@@ -1212,7 +1212,7 @@ class Compiler(metaclass=abc.ABCMeta):
     def get_feature_args(self, kwargs: T.Dict[str, T.Any], build_to_src: str) -> T.List[str]:
         """Used by D for extra language features."""
         # TODO: using a TypeDict here would improve this
-        raise EnvironmentError('{} does not implement get_feature_args'.format(self.id))
+        raise OSError('{} does not implement get_feature_args'.format(self.id))
 
     def get_prelink_args(self, prelink_name: str, obj_list: T.List[str]) -> T.List[str]:
         raise EnvironmentException('{} does not know how to do prelinking.'.format(self.id))
diff --git a/mesonbuild/compilers/cuda.py b/mesonbuild/compilers/cuda.py
index 733e362..a55975a 100644
--- a/mesonbuild/compilers/cuda.py
+++ b/mesonbuild/compilers/cuda.py
@@ -514,7 +514,7 @@ class CudaCompiler(Compiler):
         mlog.debug(stde)
         mlog.debug('-----')
         if pc.returncode != 0:
-            raise EnvironmentException('Compiler {0} can not compile programs.'.format(self.name_string()))
+            raise EnvironmentException('Compiler {} can not compile programs.'.format(self.name_string()))
 
         # Run sanity check (if possible)
         if self.is_cross:
@@ -533,7 +533,7 @@ class CudaCompiler(Compiler):
         mlog.debug('-----')
         pe.wait()
         if pe.returncode != 0:
-            raise EnvironmentException('Executables created by {0} compiler {1} are not runnable.'.format(self.language, self.name_string()))
+            raise EnvironmentException('Executables created by {} compiler {} are not runnable.'.format(self.language, self.name_string()))
 
         # Interpret the result of the sanity test.
         # As mentioned above, it is not only a sanity test but also a GPU
diff --git a/mesonbuild/compilers/d.py b/mesonbuild/compilers/d.py
index ef261fd..b16aca8 100644
--- a/mesonbuild/compilers/d.py
+++ b/mesonbuild/compilers/d.py
@@ -183,10 +183,10 @@ class DmdLikeCompilerMixin(CompilerMixinBase):
                     if int(d) > debug_level:
                         debug_level = int(d)
                 else:
-                    res.append('{0}={1}'.format(debug_arg, d))
+                    res.append('{}={}'.format(debug_arg, d))
 
             if debug_level >= 0:
-                res.append('{0}={1}'.format(debug_arg, debug_level))
+                res.append('{}={}'.format(debug_arg, debug_level))
 
         if 'versions' in kwargs:
             version_level = -1
@@ -207,10 +207,10 @@ class DmdLikeCompilerMixin(CompilerMixinBase):
                     if int(v) > version_level:
                         version_level = int(v)
                 else:
-                    res.append('{0}={1}'.format(version_arg, v))
+                    res.append('{}={}'.format(version_arg, v))
 
             if version_level >= 0:
-                res.append('{0}={1}'.format(version_arg, version_level))
+                res.append('{}={}'.format(version_arg, version_level))
 
         if 'import_dirs' in kwargs:
             import_dirs = kwargs.pop('import_dirs')
@@ -230,8 +230,8 @@ class DmdLikeCompilerMixin(CompilerMixinBase):
                     else:
                         expdir = basedir
                     srctreedir = os.path.join(build_to_src, expdir)
-                    res.append('{0}{1}'.format(import_dir_arg, srctreedir))
-                    res.append('{0}{1}'.format(import_dir_arg, bldtreedir))
+                    res.append('{}{}'.format(import_dir_arg, srctreedir))
+                    res.append('{}{}'.format(import_dir_arg, bldtreedir))
 
         if kwargs:
             raise EnvironmentException('Unknown D compiler feature(s) selected: %s' % ', '.join(kwargs.keys()))
@@ -560,10 +560,10 @@ class DCompiler(Compiler):
                     if int(d) > debug_level:
                         debug_level = int(d)
                 else:
-                    res.append('{0}={1}'.format(debug_arg, d))
+                    res.append('{}={}'.format(debug_arg, d))
 
             if debug_level >= 0:
-                res.append('{0}={1}'.format(debug_arg, debug_level))
+                res.append('{}={}'.format(debug_arg, debug_level))
 
         if 'versions' in kwargs:
             version_level = -1
@@ -584,10 +584,10 @@ class DCompiler(Compiler):
                     if int(v) > version_level:
                         version_level = int(v)
                 else:
-                    res.append('{0}={1}'.format(version_arg, v))
+                    res.append('{}={}'.format(version_arg, v))
 
             if version_level >= 0:
-                res.append('{0}={1}'.format(version_arg, version_level))
+                res.append('{}={}'.format(version_arg, version_level))
 
         if 'import_dirs' in kwargs:
             import_dirs = kwargs.pop('import_dirs')
@@ -607,8 +607,8 @@ class DCompiler(Compiler):
                     else:
                         expdir = basedir
                     srctreedir = os.path.join(build_to_src, expdir)
-                    res.append('{0}{1}'.format(import_dir_arg, srctreedir))
-                    res.append('{0}{1}'.format(import_dir_arg, bldtreedir))
+                    res.append('{}{}'.format(import_dir_arg, srctreedir))
+                    res.append('{}{}'.format(import_dir_arg, bldtreedir))
 
         if kwargs:
             raise EnvironmentException('Unknown D compiler feature(s) selected: %s' % ', '.join(kwargs.keys()))
diff --git a/mesonbuild/compilers/mixins/clike.py b/mesonbuild/compilers/mixins/clike.py
index ad3bfae..ad0e257 100644
--- a/mesonbuild/compilers/mixins/clike.py
+++ b/mesonbuild/compilers/mixins/clike.py
@@ -321,7 +321,7 @@ class CLikeCompiler(Compiler):
         mlog.debug(stde)
         mlog.debug('-----')
         if pc.returncode != 0:
-            raise mesonlib.EnvironmentException('Compiler {0} can not compile programs.'.format(self.name_string()))
+            raise mesonlib.EnvironmentException('Compiler {} can not compile programs.'.format(self.name_string()))
         # Run sanity check
         if self.is_cross:
             if self.exe_wrapper is None:
@@ -337,7 +337,7 @@ class CLikeCompiler(Compiler):
             raise mesonlib.EnvironmentException('Could not invoke sanity test executable: %s.' % str(e))
         pe.wait()
         if pe.returncode != 0:
-            raise mesonlib.EnvironmentException('Executables created by {0} compiler {1} are not runnable.'.format(self.language, self.name_string()))
+            raise mesonlib.EnvironmentException('Executables created by {} compiler {} are not runnable.'.format(self.language, self.name_string()))
 
     def sanity_check(self, work_dir: str, environment: 'Environment') -> None:
         code = 'int main(void) { int class=0; return class; }\n'
@@ -810,7 +810,7 @@ class CLikeCompiler(Compiler):
             if val is not None:
                 if isinstance(val, bool):
                     return val, False
-                raise mesonlib.EnvironmentException('Cross variable {0} is not a boolean.'.format(varname))
+                raise mesonlib.EnvironmentException('Cross variable {} is not a boolean.'.format(varname))
 
         # TODO: we really need a protocol for this,
         #
diff --git a/mesonbuild/coredata.py b/mesonbuild/coredata.py
index 3d74139..99646ca 100644
--- a/mesonbuild/coredata.py
+++ b/mesonbuild/coredata.py
@@ -235,7 +235,7 @@ class UserArrayOption(UserOption[T.List[str]]):
             mlog.deprecation(msg)
         for i in newvalue:
             if not isinstance(i, str):
-                raise MesonException('String array element "{0}" is not a string.'.format(str(newvalue)))
+                raise MesonException('String array element "{}" is not a string.'.format(str(newvalue)))
         if self.choices:
             bad = [x for x in newvalue if x not in self.choices]
             if bad:
@@ -434,7 +434,7 @@ class CoreData:
                     # the contents of that file into the meson private (scratch)
                     # directory so that it can be re-read when wiping/reconfiguring
                     copy = os.path.join(scratch_dir, '{}.{}.ini'.format(uuid.uuid4(), ftype))
-                    with open(f, 'r') as rf:
+                    with open(f) as rf:
                         with open(copy, 'w') as wf:
                             wf.write(rf.read())
                     real.append(copy)
diff --git a/mesonbuild/dependencies/cuda.py b/mesonbuild/dependencies/cuda.py
index 20f6569..6d17b90 100644
--- a/mesonbuild/dependencies/cuda.py
+++ b/mesonbuild/dependencies/cuda.py
@@ -130,7 +130,7 @@ class CudaDependency(ExternalDependency):
     def _default_path_env_var(self):
         env_vars = ['CUDA_PATH'] if self._is_windows() else ['CUDA_PATH', 'CUDA_HOME', 'CUDA_ROOT']
         env_vars = [var for var in env_vars if var in os.environ]
-        user_defaults = set([os.environ[var] for var in env_vars])
+        user_defaults = {os.environ[var] for var in env_vars}
         if len(user_defaults) > 1:
             mlog.warning('Environment variables {} point to conflicting toolkit locations ({}). Toolkit selection might produce unexpected results.'.format(', '.join(env_vars), ', '.join(user_defaults)))
         return env_vars[0] if env_vars else None
diff --git a/mesonbuild/dependencies/hdf5.py b/mesonbuild/dependencies/hdf5.py
index 5ac60bb..7c35a02 100644
--- a/mesonbuild/dependencies/hdf5.py
+++ b/mesonbuild/dependencies/hdf5.py
@@ -167,7 +167,7 @@ def hdf5_factory(env: 'Environment', for_machine: 'MachineChoice',
                                     universal_newlines=True)
             if ret.returncode == 0:
                 for pkg in ret.stdout.split('\n'):
-                    if pkg.startswith(('hdf5')):
+                    if pkg.startswith('hdf5'):
                         pkgconfig_files.add(pkg.split(' ', 1)[0])
 
         for pkg in pkgconfig_files:
diff --git a/mesonbuild/environment.py b/mesonbuild/environment.py
index 756dd81..4d9d592 100644
--- a/mesonbuild/environment.py
+++ b/mesonbuild/environment.py
@@ -1020,7 +1020,7 @@ class Environment:
         if exceptions:
             errmsg += '\nThe following exception(s) were encountered:'
             for (c, e) in exceptions.items():
-                errmsg += '\nRunning "{0}" gave "{1}"'.format(c, e)
+                errmsg += '\nRunning "{}" gave "{}"'.format(c, e)
         raise EnvironmentException(errmsg)
 
     @staticmethod
@@ -1208,7 +1208,7 @@ class Environment:
                 compiler = [compiler]
             compiler_name = os.path.basename(compiler[0])
 
-            if not set(['cl', 'cl.exe', 'clang-cl', 'clang-cl.exe']).isdisjoint(compiler):
+            if not {'cl', 'cl.exe', 'clang-cl', 'clang-cl.exe'}.isdisjoint(compiler):
                 # Watcom C provides it's own cl.exe clone that mimics an older
                 # version of Microsoft's compiler. Since Watcom's cl.exe is
                 # just a wrapper, we skip using it if we detect its presence
diff --git a/mesonbuild/interpreter.py b/mesonbuild/interpreter.py
index 2cc4f44..1a861fb 100644
--- a/mesonbuild/interpreter.py
+++ b/mesonbuild/interpreter.py
@@ -1039,25 +1039,25 @@ class SubprojectHolder(InterpreterObject, ObjectHolder[T.Optional['Interpreter']
         if len(args) == 2:
             return args[1]
 
-        raise InvalidArguments('Requested variable "{0}" not found.'.format(varname))
+        raise InvalidArguments('Requested variable "{}" not found.'.format(varname))
 
-header_permitted_kwargs = set([
+header_permitted_kwargs = {
     'required',
     'prefix',
     'no_builtin_args',
     'include_directories',
     'args',
     'dependencies',
-])
+}
 
-find_library_permitted_kwargs = set([
+find_library_permitted_kwargs = {
     'has_headers',
     'required',
     'dirs',
     'static',
-])
+}
 
-find_library_permitted_kwargs |= set(['header_' + k for k in header_permitted_kwargs])
+find_library_permitted_kwargs |= {'header_' + k for k in header_permitted_kwargs}
 
 class CompilerHolder(InterpreterObject):
     def __init__(self, compiler: 'Compiler', env: 'Environment', subproject: str):
@@ -1585,7 +1585,7 @@ class CompilerHolder(InterpreterObject):
             raise InterpreterException('Prefix argument of has_header_symbol must be a string.')
         disabled, required, feature = extract_required_kwarg(kwargs, self.subproject, default=False)
         if disabled:
-            mlog.log('Header <{0}> has symbol'.format(hname), mlog.bold(symbol, True), 'skipped: feature', mlog.bold(feature), 'disabled')
+            mlog.log('Header <{}> has symbol'.format(hname), mlog.bold(symbol, True), 'skipped: feature', mlog.bold(feature), 'disabled')
             return False
         extra_args = functools.partial(self.determine_args, kwargs)
         deps, msg = self.determine_dependencies(kwargs)
@@ -1599,7 +1599,7 @@ class CompilerHolder(InterpreterObject):
         else:
             h = mlog.red('NO')
         cached = mlog.blue('(cached)') if cached else ''
-        mlog.log('Header <{0}> has symbol'.format(hname), mlog.bold(symbol, True), msg, h, cached)
+        mlog.log('Header <{}> has symbol'.format(hname), mlog.bold(symbol, True), msg, h, cached)
         return haz
 
     def notfound_library(self, libname):
@@ -4346,7 +4346,7 @@ This will become a hard error in the future.''' % kwargs['input'], location=self
     def func_configure_file(self, node, args, kwargs):
         if 'output' not in kwargs:
             raise InterpreterException('Required keyword argument "output" not defined.')
-        actions = set(['configuration', 'command', 'copy']).intersection(kwargs.keys())
+        actions = {'configuration', 'command', 'copy'}.intersection(kwargs.keys())
         if len(actions) == 0:
             raise InterpreterException('Must specify an action with one of these '
                                        'keyword arguments: \'configuration\', '
@@ -4483,7 +4483,7 @@ This will become a hard error in the future.''' % kwargs['input'], location=self
                 mesonlib.replace_if_different(ofile_abs, dst_tmp)
             if depfile:
                 mlog.log('Reading depfile:', mlog.bold(depfile))
-                with open(depfile, 'r') as f:
+                with open(depfile) as f:
                     df = DepFile(f.readlines())
                     deps = df.get_all_dependencies(ofile_fname)
                     for dep in deps:
diff --git a/mesonbuild/linkers.py b/mesonbuild/linkers.py
index d8d2e65..f4c6dca 100644
--- a/mesonbuild/linkers.py
+++ b/mesonbuild/linkers.py
@@ -838,7 +838,7 @@ class CcrxDynamicLinker(DynamicLinker):
         return ['-output={}'.format(outputname)]
 
     def get_search_args(self, dirname: str) -> 'T.NoReturn':
-        raise EnvironmentError('rlink.exe does not have a search dir argument')
+        raise OSError('rlink.exe does not have a search dir argument')
 
     def get_allow_undefined_args(self) -> T.List[str]:
         return []
@@ -878,7 +878,7 @@ class Xc16DynamicLinker(DynamicLinker):
         return ['-o{}'.format(outputname)]
 
     def get_search_args(self, dirname: str) -> 'T.NoReturn':
-        raise EnvironmentError('xc16-gcc.exe does not have a search dir argument')
+        raise OSError('xc16-gcc.exe does not have a search dir argument')
 
     def get_allow_undefined_args(self) -> T.List[str]:
         return []
@@ -966,7 +966,7 @@ class C2000DynamicLinker(DynamicLinker):
         return ['-z', '--output_file={}'.format(outputname)]
 
     def get_search_args(self, dirname: str) -> 'T.NoReturn':
-        raise EnvironmentError('cl2000.exe does not have a search dir argument')
+        raise OSError('cl2000.exe does not have a search dir argument')
 
     def get_allow_undefined_args(self) -> T.List[str]:
         return []
diff --git a/mesonbuild/mconf.py b/mesonbuild/mconf.py
index 9b2f5b6..13530ec 100644
--- a/mesonbuild/mconf.py
+++ b/mesonbuild/mconf.py
@@ -123,7 +123,7 @@ class Conf:
 
     def add_option(self, name, descr, value, choices):
         if isinstance(value, list):
-            value = '[{0}]'.format(', '.join(make_lower_case(value)))
+            value = '[{}]'.format(', '.join(make_lower_case(value)))
         else:
             value = make_lower_case(value)
 
diff --git a/mesonbuild/mintro.py b/mesonbuild/mintro.py
index 9d8682c..f4b8e0b 100644
--- a/mesonbuild/mintro.py
+++ b/mesonbuild/mintro.py
@@ -394,7 +394,7 @@ def get_info_file(infodir: str, kind: T.Optional[str] = None) -> str:
                         'meson-info.json' if not kind else 'intro-{}.json'.format(kind))
 
 def load_info_file(infodir: str, kind: T.Optional[str] = None) -> T.Any:
-    with open(get_info_file(infodir, kind), 'r') as fp:
+    with open(get_info_file(infodir, kind)) as fp:
         return json.load(fp)
 
 def run(options: argparse.Namespace) -> int:
diff --git a/mesonbuild/mlog.py b/mesonbuild/mlog.py
index 20794df..dbc48a1 100644
--- a/mesonbuild/mlog.py
+++ b/mesonbuild/mlog.py
@@ -142,10 +142,10 @@ class AnsiText:
         self.args = args
 
     def __len__(self) -> int:
-        return sum((len(x) for x in self.args))
+        return sum(len(x) for x in self.args)
 
     def __str__(self) -> str:
-        return ''.join((str(x) for x in self.args))
+        return ''.join(str(x) for x in self.args)
 
 
 def bold(text: str, quoted: bool = False) -> AnsiDecorator:
diff --git a/mesonbuild/modules/cmake.py b/mesonbuild/modules/cmake.py
index dc45e71..18dc2f5 100644
--- a/mesonbuild/modules/cmake.py
+++ b/mesonbuild/modules/cmake.py
@@ -235,7 +235,7 @@ class CmakeModule(ExtensionModule):
         cmakebin = dependencies.ExternalProgram('cmake', silent=False)
         p, stdout, stderr = mesonlib.Popen_safe(cmakebin.get_command() + ['--system-information', '-G', 'Ninja'])[0:3]
         if p.returncode != 0:
-            mlog.log('error retrieving cmake information: returnCode={0} stdout={1} stderr={2}'.format(p.returncode, stdout, stderr))
+            mlog.log('error retrieving cmake information: returnCode={} stdout={} stderr={}'.format(p.returncode, stdout, stderr))
             return False
 
         match = re.search('\nCMAKE_ROOT \\"([^"]+)"\n', stdout.strip())
@@ -295,7 +295,7 @@ class CmakeModule(ExtensionModule):
         package_init += PACKAGE_INIT_SET_AND_CHECK
 
         try:
-            with open(infile, "r") as fin:
+            with open(infile) as fin:
                 data = fin.readlines()
         except Exception as e:
             raise mesonlib.MesonException('Could not read input file %s: %s' % (infile, str(e)))
diff --git a/mesonbuild/modules/dlang.py b/mesonbuild/modules/dlang.py
index d4f62e4..55ff304 100644
--- a/mesonbuild/modules/dlang.py
+++ b/mesonbuild/modules/dlang.py
@@ -70,7 +70,7 @@ class DlangModule(ExtensionModule):
 
         config_path = os.path.join(args[1], 'dub.json')
         if os.path.exists(config_path):
-            with open(config_path, 'r', encoding='utf8') as ofile:
+            with open(config_path, encoding='utf8') as ofile:
                 try:
                     config = json.load(ofile)
                 except ValueError:
diff --git a/mesonbuild/modules/fs.py b/mesonbuild/modules/fs.py
index 7de8cf7..fd1e99b 100644
--- a/mesonbuild/modules/fs.py
+++ b/mesonbuild/modules/fs.py
@@ -211,7 +211,7 @@ class FSModule(ExtensionModule):
         if path_is_in_root(Path(path), Path(build_dir), resolve=True):
             raise MesonException('path must not be in the build tree')
         try:
-            with open(path, 'r', encoding=encoding) as f:
+            with open(path, encoding=encoding) as f:
                 data = f.read()
         except UnicodeDecodeError:
             raise MesonException(f'decoding failed for {path}')
diff --git a/mesonbuild/modules/keyval.py b/mesonbuild/modules/keyval.py
index 3da2992..8e1a89f 100644
--- a/mesonbuild/modules/keyval.py
+++ b/mesonbuild/modules/keyval.py
@@ -42,7 +42,7 @@ class KeyvalModule(ExtensionModule):
                     except ValueError:
                         continue
                     result[name.strip()] = val.strip()
-        except IOError as e:
+        except OSError as e:
             raise mesonlib.MesonException('Failed to load {}: {}'.format(path_to_config, e))
 
         return result
diff --git a/mesonbuild/modules/python.py b/mesonbuild/modules/python.py
index cfe2244..d05c72a 100644
--- a/mesonbuild/modules/python.py
+++ b/mesonbuild/modules/python.py
@@ -36,9 +36,9 @@ from ..dependencies.base import (
     NonExistingExternalProgram, NotFoundDependency
 )
 
-mod_kwargs = set(['subdir'])
+mod_kwargs = {'subdir'}
 mod_kwargs.update(known_shmod_kwargs)
-mod_kwargs -= set(['name_prefix', 'name_suffix'])
+mod_kwargs -= {'name_prefix', 'name_suffix'}
 
 class PythonDependency(ExternalDependency):
 
@@ -544,7 +544,7 @@ class PythonModule(ExtensionModule):
             for mod in want_modules:
                 p, out, err = mesonlib.Popen_safe(
                     python.command +
-                    ['-c', 'import {0}'.format(mod)])
+                    ['-c', 'import {}'.format(mod)])
                 if p.returncode != 0:
                     missing_modules.append(mod)
                 else:
diff --git a/mesonbuild/mtest.py b/mesonbuild/mtest.py
index af5ad6d..ac4f515 100644
--- a/mesonbuild/mtest.py
+++ b/mesonbuild/mtest.py
@@ -902,8 +902,8 @@ class TestRun:
             return returncode_to_status(self.returncode)
         if self.results:
             # running or succeeded
-            passed = sum((x.result.is_ok() for x in self.results))
-            ran = sum((x.result is not TestResult.SKIP for x in self.results))
+            passed = sum(x.result.is_ok() for x in self.results)
+            ran = sum(x.result is not TestResult.SKIP for x in self.results)
             if passed == ran:
                 return '{} subtests passed'.format(passed)
             else:
@@ -928,7 +928,7 @@ class TestRun:
             return None
         test_only_env = set(self.env.items()) - set(os.environ.items())
         return env_tuple_to_str(test_only_env) + \
-            ' '.join((sh_quote(x) for x in self.cmd))
+            ' '.join(sh_quote(x) for x in self.cmd)
 
     def complete_skip(self, message: str) -> None:
         self.starttime = time.time()
@@ -1634,13 +1634,13 @@ class TestHarness:
                 os.chdir(self.options.wd)
             runners = []             # type: T.List[SingleTestRunner]
             for i in range(self.options.repeat):
-                runners.extend((self.get_test_runner(test) for test in tests))
+                runners.extend(self.get_test_runner(test) for test in tests)
                 if i == 0:
                     self.duration_max_len = max([len(str(int(runner.timeout or 99)))
                                                  for runner in runners])
                     # Disable the progress report if it gets in the way
-                    self.need_console = any((runner.console_mode is not ConsoleUser.LOGGER
-                                             for runner in runners))
+                    self.need_console = any(runner.console_mode is not ConsoleUser.LOGGER
+                                             for runner in runners)
 
             self.test_count = len(runners)
             self.run_tests(runners)
diff --git a/mesonbuild/optinterpreter.py b/mesonbuild/optinterpreter.py
index dc8c3ce..6043691 100644
--- a/mesonbuild/optinterpreter.py
+++ b/mesonbuild/optinterpreter.py
@@ -142,7 +142,7 @@ class OptionInterpreter:
 
     def process(self, option_file: str) -> None:
         try:
-            with open(option_file, 'r', encoding='utf8') as f:
+            with open(option_file, encoding='utf8') as f:
                 ast = mparser.Parser(f.read(), option_file).parse()
         except mesonlib.MesonException as me:
             me.file = option_file
diff --git a/mesonbuild/rewriter.py b/mesonbuild/rewriter.py
index 9cd9ad0..8585833 100644
--- a/mesonbuild/rewriter.py
+++ b/mesonbuild/rewriter.py
@@ -820,7 +820,7 @@ class Rewriter:
             if not os.path.exists(fpath):
                 with open(fpath, 'w'):
                     pass
-            with open(fpath, 'r') as fp:
+            with open(fpath) as fp:
                 fdata = fp.read()
 
             # Generate line offsets numbers
@@ -923,7 +923,7 @@ def generate_def_opts(options) -> T.List[dict]:
 
 def generate_cmd(options) -> T.List[dict]:
     if os.path.exists(options.json):
-        with open(options.json, 'r') as fp:
+        with open(options.json) as fp:
             return json.load(fp)
     else:
         return json.loads(options.json)
diff --git a/mesonbuild/scripts/meson_exe.py b/mesonbuild/scripts/meson_exe.py
index 27db144..d44280f 100644
--- a/mesonbuild/scripts/meson_exe.py
+++ b/mesonbuild/scripts/meson_exe.py
@@ -82,7 +82,7 @@ def run_exe(exe: ExecutableSerialisation, extra_env: T.Optional[dict] = None) ->
         try:
             with open(exe.capture, 'rb') as cur:
                 skip_write = cur.read() == stdout
-        except IOError:
+        except OSError:
             pass
         if not skip_write:
             with open(exe.capture, 'wb') as output:
diff --git a/mesonbuild/scripts/symbolextractor.py b/mesonbuild/scripts/symbolextractor.py
index 30065cc..e80d9c2fac 100644
--- a/mesonbuild/scripts/symbolextractor.py
+++ b/mesonbuild/scripts/symbolextractor.py
@@ -43,7 +43,7 @@ def dummy_syms(outfilename: str) -> None:
 
 def write_if_changed(text: str, outfilename: str) -> None:
     try:
-        with open(outfilename, 'r') as f:
+        with open(outfilename) as f:
             oldtext = f.read()
         if text == oldtext:
             return
diff --git a/mesonbuild/wrap/wrap.py b/mesonbuild/wrap/wrap.py
index 7ec8b50..ca201de 100644
--- a/mesonbuild/wrap/wrap.py
+++ b/mesonbuild/wrap/wrap.py
@@ -442,7 +442,7 @@ class Resolver:
     def is_git_full_commit_id(self, revno: str) -> bool:
         result = False
         if len(revno) in (40, 64): # 40 for sha1, 64 for upcoming sha256
-            result = all((ch in '0123456789AaBbCcDdEeFf' for ch in revno))
+            result = all(ch in '0123456789AaBbCcDdEeFf' for ch in revno)
         return result
 
     def get_hg(self) -> None:
diff --git a/packaging/createmsi.py b/packaging/createmsi.py
index 98c0bd6..f279df5 100644
--- a/packaging/createmsi.py
+++ b/packaging/createmsi.py
@@ -277,7 +277,7 @@ class PackageGenerator:
         with open(self.main_xml, 'w') as open_file:
             open_file.write(doc.toprettyxml())
         # One last fix, add CDATA.
-        with open(self.main_xml, 'r') as open_file:
+        with open(self.main_xml) as open_file:
             data = open_file.read()
         data = data.replace('X'*len(WINVER_CHECK), WINVER_CHECK)
         with open(self.main_xml, 'w') as open_file:
diff --git a/run_project_tests.py b/run_project_tests.py
index b6879ee..b14e817 100755
--- a/run_project_tests.py
+++ b/run_project_tests.py
@@ -1352,7 +1352,7 @@ if __name__ == '__main__':
             except UnicodeError:
                 print(l.encode('ascii', errors='replace').decode(), '\n')
     for name, dirs, _ in all_tests:
-        dir_names = list(set(x.path.name for x in dirs))
+        dir_names = list({x.path.name for x in dirs})
         for k, g in itertools.groupby(dir_names, key=lambda x: x.split()[0]):
             tests = list(g)
             if len(tests) != 1:
diff --git a/run_tests.py b/run_tests.py
index 1e01aa9..85434e4 100755
--- a/run_tests.py
+++ b/run_tests.py
@@ -190,7 +190,7 @@ def find_vcxproj_with_target(builddir, target):
     for _, _, files in os.walk(builddir):
         for f in fnmatch.filter(files, '*.vcxproj'):
             f = os.path.join(builddir, f)
-            with open(f, 'r', encoding='utf-8') as o:
+            with open(f, encoding='utf-8') as o:
                 if re.search(p, o.read(), flags=re.MULTILINE):
                     return f
     raise RuntimeError('No vcxproj matching {!r} in {!r}'.format(p, builddir))
diff --git a/run_unittests.py b/run_unittests.py
index 0d42ced..62f28b2 100755
--- a/run_unittests.py
+++ b/run_unittests.py
@@ -1583,10 +1583,10 @@ class DataTests(unittest.TestCase):
             self.assertEqual(len(found_entries & options), 0)
             found_entries |= options
 
-        self.assertEqual(found_entries, set([
+        self.assertEqual(found_entries, {
             *[str(k) for k in mesonbuild.coredata.BUILTIN_OPTIONS],
             *[str(k) for k in mesonbuild.coredata.BUILTIN_OPTIONS_PER_MACHINE],
-        ]))
+        })
 
         # Check that `buildtype` table inside `Core options` matches how
         # setting of builtin options behaves
@@ -1682,7 +1682,7 @@ class DataTests(unittest.TestCase):
                 data_files += [(p.relative_to(mesonbuild_dir).as_posix(), hashlib.sha256(p.read_bytes()).hexdigest())]
 
         current_files = set(mesondata.keys())
-        scanned_files = set([x[0] for x in data_files])
+        scanned_files = {x[0] for x in data_files}
 
         self.assertSetEqual(current_files, scanned_files, err_msg + 'Data files were added or removed\n')
         errors = []
@@ -1764,7 +1764,7 @@ class BasePlatformTests(unittest.TestCase):
         if not os.path.isfile(log):
             print("{!r} doesn't exist".format(log))
             return
-        with open(log, 'r', encoding='utf-8') as f:
+        with open(log, encoding='utf-8') as f:
             print(f.read())
 
     def tearDown(self):
@@ -1925,7 +1925,7 @@ class BasePlatformTests(unittest.TestCase):
                 compiler, rsp = each['command'].split(' @')
                 rsp = os.path.join(self.builddir, rsp)
                 # Replace the command with its contents
-                with open(rsp, 'r', encoding='utf-8') as f:
+                with open(rsp, encoding='utf-8') as f:
                     each['command'] = compiler + ' ' + f.read()
         return contents
 
@@ -2952,7 +2952,7 @@ class AllPlatformTests(BasePlatformTests):
         self.assertNotEqual(commands['cpp-c-asm']['c'], commands['cpp-c-asm']['cpp'])
         # Check that the c-asm target is always linked with the C linker
         build_ninja = os.path.join(self.builddir, 'build.ninja')
-        with open(build_ninja, 'r', encoding='utf-8') as f:
+        with open(build_ninja, encoding='utf-8') as f:
             contents = f.read()
             m = re.search('build c-asm.*: c_LINKER', contents)
         self.assertIsNotNone(m, msg=contents)
@@ -4245,7 +4245,7 @@ class AllPlatformTests(BasePlatformTests):
         with tempfile.NamedTemporaryFile(mode='w', delete=False) as crossfile:
             crossfile.write(textwrap.dedent(
                 '''[binaries]
-                pkgconfig = '{0}'
+                pkgconfig = '{}'
 
                 [properties]
 
@@ -4275,7 +4275,7 @@ class AllPlatformTests(BasePlatformTests):
                 pkgconfig = 'pkg-config'
 
                 [properties]
-                pkg_config_libdir = ['{0}']
+                pkg_config_libdir = ['{}']
 
                 [host_machine]
                 system = 'linux'
@@ -4372,26 +4372,26 @@ class AllPlatformTests(BasePlatformTests):
     def test_introspect_projectinfo_without_configured_build(self):
         testfile = os.path.join(self.common_test_dir, '34 run program', 'meson.build')
         res = self.introspect_directory(testfile, '--projectinfo')
-        self.assertEqual(set(res['buildsystem_files']), set(['meson.build']))
+        self.assertEqual(set(res['buildsystem_files']), {'meson.build'})
         self.assertEqual(res['version'], 'undefined')
         self.assertEqual(res['descriptive_name'], 'run command')
         self.assertEqual(res['subprojects'], [])
 
         testfile = os.path.join(self.common_test_dir, '41 options', 'meson.build')
         res = self.introspect_directory(testfile, '--projectinfo')
-        self.assertEqual(set(res['buildsystem_files']), set(['meson_options.txt', 'meson.build']))
+        self.assertEqual(set(res['buildsystem_files']), {'meson_options.txt', 'meson.build'})
         self.assertEqual(res['version'], 'undefined')
         self.assertEqual(res['descriptive_name'], 'options')
         self.assertEqual(res['subprojects'], [])
 
         testfile = os.path.join(self.common_test_dir, '44 subproject options', 'meson.build')
         res = self.introspect_directory(testfile, '--projectinfo')
-        self.assertEqual(set(res['buildsystem_files']), set(['meson_options.txt', 'meson.build']))
+        self.assertEqual(set(res['buildsystem_files']), {'meson_options.txt', 'meson.build'})
         self.assertEqual(res['version'], 'undefined')
         self.assertEqual(res['descriptive_name'], 'suboptions')
         self.assertEqual(len(res['subprojects']), 1)
-        subproject_files = set(f.replace('\\', '/') for f in res['subprojects'][0]['buildsystem_files'])
-        self.assertEqual(subproject_files, set(['subprojects/subproject/meson_options.txt', 'subprojects/subproject/meson.build']))
+        subproject_files = {f.replace('\\', '/') for f in res['subprojects'][0]['buildsystem_files']}
+        self.assertEqual(subproject_files, {'subprojects/subproject/meson_options.txt', 'subprojects/subproject/meson.build'})
         self.assertEqual(res['subprojects'][0]['name'], 'subproject')
         self.assertEqual(res['subprojects'][0]['version'], 'undefined')
         self.assertEqual(res['subprojects'][0]['descriptive_name'], 'subproject')
@@ -4544,7 +4544,7 @@ class AllPlatformTests(BasePlatformTests):
         infodir = os.path.join(self.builddir, 'meson-info')
         self.assertPathExists(infodir)
 
-        with open(os.path.join(infodir, 'intro-targets.json'), 'r') as fp:
+        with open(os.path.join(infodir, 'intro-targets.json')) as fp:
             targets = json.load(fp)
 
         for i in targets:
@@ -4653,7 +4653,7 @@ class AllPlatformTests(BasePlatformTests):
         for i in root_keylist:
             curr = os.path.join(infodir, 'intro-{}.json'.format(i[0]))
             self.assertPathExists(curr)
-            with open(curr, 'r') as fp:
+            with open(curr) as fp:
                 res[i[0]] = json.load(fp)
 
         assertKeyTypes(root_keylist, res)
@@ -4761,7 +4761,7 @@ class AllPlatformTests(BasePlatformTests):
         for i in root_keylist:
             curr = os.path.join(infodir, 'intro-{}.json'.format(i))
             self.assertPathExists(curr)
-            with open(curr, 'r') as fp:
+            with open(curr) as fp:
                 res_file[i] = json.load(fp)
 
         self.assertEqual(res_all, res_file)
@@ -4771,7 +4771,7 @@ class AllPlatformTests(BasePlatformTests):
         introfile = os.path.join(self.builddir, 'meson-info', 'meson-info.json')
         self.init(testdir)
         self.assertPathExists(introfile)
-        with open(introfile, 'r') as fp:
+        with open(introfile) as fp:
             res1 = json.load(fp)
 
         for i in ['meson_version', 'directories', 'introspection', 'build_files_updated', 'error']:
@@ -4785,7 +4785,7 @@ class AllPlatformTests(BasePlatformTests):
         introfile = os.path.join(self.builddir, 'meson-info', 'intro-buildoptions.json')
         self.init(testdir)
         self.assertPathExists(introfile)
-        with open(introfile, 'r') as fp:
+        with open(introfile) as fp:
             res1 = json.load(fp)
 
         for i in res1:
@@ -4803,7 +4803,7 @@ class AllPlatformTests(BasePlatformTests):
         self.setconf('-Dcpp_std=c++14')
         self.setconf('-Dbuildtype=release')
 
-        with open(introfile, 'r') as fp:
+        with open(introfile) as fp:
             res2 = json.load(fp)
 
         self.assertListEqual(res1, res2)
@@ -4814,7 +4814,7 @@ class AllPlatformTests(BasePlatformTests):
         introfile = os.path.join(self.builddir, 'meson-info', 'intro-targets.json')
         self.init(testdir)
         self.assertPathExists(introfile)
-        with open(introfile, 'r') as fp:
+        with open(introfile) as fp:
             res_wb = json.load(fp)
 
         res_nb = self.introspect_directory(testfile, ['--targets'] + self.meson_args)
@@ -5190,7 +5190,7 @@ class AllPlatformTests(BasePlatformTests):
         self.init(testdir)
 
         build_ninja = os.path.join(self.builddir, 'build.ninja')
-        with open(build_ninja, 'r', encoding='utf-8') as f:
+        with open(build_ninja, encoding='utf-8') as f:
             contents = f.read()
 
         self.assertRegex(contents, r'build main(\.exe)?.*: c_LINKER')
@@ -5222,10 +5222,10 @@ class AllPlatformTests(BasePlatformTests):
 
         ## Validate commands
 
-        md_commands = set(k for k,v in md_command_sections.items())
+        md_commands = {k for k,v in md_command_sections.items()}
 
         help_output = self._run(self.meson_command + ['--help'])
-        help_commands = set(c.strip() for c in re.findall(r'usage:(?:.+)?{((?:[a-z]+,*)+?)}', help_output, re.MULTILINE|re.DOTALL)[0].split(','))
+        help_commands = {c.strip() for c in re.findall(r'usage:(?:.+)?{((?:[a-z]+,*)+?)}', help_output, re.MULTILINE|re.DOTALL)[0].split(',')}
 
         self.assertEqual(md_commands | {'help'}, help_commands, 'Doc file: `{}`'.format(doc_path))
 
@@ -6151,7 +6151,7 @@ class WindowsTests(BasePlatformTests):
         self.init(testdir, extra_args=['-Db_vscrt=mdd'])
         # Verify that we're linking to the debug versions of Qt DLLs
         build_ninja = os.path.join(self.builddir, 'build.ninja')
-        with open(build_ninja, 'r', encoding='utf-8') as f:
+        with open(build_ninja, encoding='utf-8') as f:
             contents = f.read()
             m = re.search('build qt5core.exe: cpp_LINKER.*Qt5Cored.lib', contents)
         self.assertIsNotNone(m, msg=contents)
@@ -6245,7 +6245,7 @@ class DarwinTests(BasePlatformTests):
                 self.assertIn('-fembed-bitcode', compdb['command'])
         build_ninja = os.path.join(self.builddir, 'build.ninja')
         # Linker options were added
-        with open(build_ninja, 'r', encoding='utf-8') as f:
+        with open(build_ninja, encoding='utf-8') as f:
             contents = f.read()
             m = re.search('LINK_ARGS =.*-bitcode_bundle', contents)
         self.assertIsNotNone(m, msg=contents)
@@ -6256,7 +6256,7 @@ class DarwinTests(BasePlatformTests):
         for compdb in self.get_compdb():
             self.assertNotIn('-fembed-bitcode', compdb['command'])
         build_ninja = os.path.join(self.builddir, 'build.ninja')
-        with open(build_ninja, 'r', encoding='utf-8') as f:
+        with open(build_ninja, encoding='utf-8') as f:
             contents = f.read()
             m = re.search('LINK_ARGS =.*-bitcode_bundle', contents)
         self.assertIsNone(m, msg=contents)
@@ -7601,7 +7601,7 @@ class LinuxlikeTests(BasePlatformTests):
         build_ninja = os.path.join(self.builddir, 'build.ninja')
         max_count = 0
         search_term = '-Wl,--export-dynamic'
-        with open(build_ninja, 'r', encoding='utf-8') as f:
+        with open(build_ninja, encoding='utf-8') as f:
             for line in f:
                 max_count = max(max_count, line.count(search_term))
         self.assertEqual(max_count, 1, 'Export dynamic incorrectly deduplicated.')
@@ -7610,7 +7610,7 @@ class LinuxlikeTests(BasePlatformTests):
         testdir = os.path.join(self.unit_test_dir, '56 dedup compiler libs')
         self.init(testdir)
         build_ninja = os.path.join(self.builddir, 'build.ninja')
-        with open(build_ninja, 'r', encoding='utf-8') as f:
+        with open(build_ninja, encoding='utf-8') as f:
             lines = f.readlines()
         for lib in ('-ldl', '-lm', '-lc', '-lrt'):
             for line in lines:
@@ -7636,7 +7636,7 @@ class LinuxlikeTests(BasePlatformTests):
         nativefile = tempfile.NamedTemporaryFile(mode='w')
         nativefile.write(textwrap.dedent('''\
             [binaries]
-            c = ['{0}']
+            c = ['{}']
             '''.format(os.path.join(testdir, 'build_wrapper.py'))))
         nativefile.flush()
         self.meson_native_file = nativefile.name
@@ -7644,7 +7644,7 @@ class LinuxlikeTests(BasePlatformTests):
         crossfile = tempfile.NamedTemporaryFile(mode='w')
         crossfile.write(textwrap.dedent('''\
             [binaries]
-            c = ['{0}']
+            c = ['{}']
             '''.format(os.path.join(testdir, 'host_wrapper.py'))))
         crossfile.flush()
         self.meson_cross_file = crossfile.name
@@ -7660,7 +7660,7 @@ class LinuxlikeTests(BasePlatformTests):
         crossfile = tempfile.NamedTemporaryFile(mode='w')
         crossfile.write(textwrap.dedent('''\
             [binaries]
-            c = ['{0}']
+            c = ['{}']
             '''.format(os.path.join(testdir, 'host_wrapper.py'))))
         crossfile.flush()
         self.meson_cross_file = crossfile.name
diff --git a/skip_ci.py b/skip_ci.py
index 5e0a7aa..4ee4466 100755
--- a/skip_ci.py
+++ b/skip_ci.py
@@ -13,7 +13,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-from __future__ import print_function
 
 import argparse
 import os
diff --git a/test cases/common/106 generatorcustom/catter.py b/test cases/common/106 generatorcustom/catter.py
index 198fa98..c272672 100755
--- a/test cases/common/106 generatorcustom/catter.py
+++ b/test cases/common/106 generatorcustom/catter.py
@@ -8,7 +8,7 @@ inputs = sys.argv[1:-1]
 with open(output, 'w') as ofile:
     ofile.write('#pragma once\n')
     for i in inputs:
-        with open(i, 'r') as ifile:
+        with open(i) as ifile:
             content = ifile.read()
         ofile.write(content)
         ofile.write('\n')
diff --git a/test cases/common/106 generatorcustom/gen.py b/test cases/common/106 generatorcustom/gen.py
index c1e34ed..1464008 100755
--- a/test cases/common/106 generatorcustom/gen.py
+++ b/test cases/common/106 generatorcustom/gen.py
@@ -5,7 +5,7 @@ import sys
 ifile = sys.argv[1]
 ofile = sys.argv[2]
 
-with open(ifile, 'r') as f:
+with open(ifile) as f:
     resname = f.readline().strip()
 
 templ = 'const char %s[] = "%s";\n'
diff --git a/test cases/common/126 configure file in generator/src/gen.py b/test cases/common/126 configure file in generator/src/gen.py
index 99b7cdd..426d0b7 100755
--- a/test cases/common/126 configure file in generator/src/gen.py
+++ b/test cases/common/126 configure file in generator/src/gen.py
@@ -5,7 +5,7 @@ import sys
 ifile = sys.argv[1]
 ofile = sys.argv[2]
 
-with open(ifile, 'r') as f:
+with open(ifile) as f:
     resval = f.readline().strip()
 
 templ = '#define RESULT (%s)\n'
diff --git a/test cases/common/14 configure file/file_contains.py b/test cases/common/14 configure file/file_contains.py
index 25634f5..409f09c 100644
--- a/test cases/common/14 configure file/file_contains.py
+++ b/test cases/common/14 configure file/file_contains.py
@@ -11,7 +11,7 @@ def main():
 
     text = args.text[0]
 
-    with open(args.file[0], 'r', encoding='utf-8') as f:
+    with open(args.file[0], encoding='utf-8') as f:
         for line in f:
             if line.strip() == text:
                 return 0
diff --git a/test cases/common/52 run target/fakeburner.py b/test cases/common/52 run target/fakeburner.py
index da3d0ac..8b1f353 100755
--- a/test cases/common/52 run target/fakeburner.py
+++ b/test cases/common/52 run target/fakeburner.py
@@ -1,6 +1,5 @@
 #!/usr/bin/env python3
 
-from __future__ import print_function
 
 import sys
 
diff --git a/test cases/common/71 external test program/mytest.py b/test cases/common/71 external test program/mytest.py
index 9947773..fee94e0 100755
--- a/test cases/common/71 external test program/mytest.py
+++ b/test cases/common/71 external test program/mytest.py
@@ -1,6 +1,5 @@
 #!/usr/bin/env python3
 
-from __future__ import print_function
 
 import sys
 
diff --git a/test cases/common/72 ctarget dependency/gen1.py b/test cases/common/72 ctarget dependency/gen1.py
index 0fa6ea1..dbadb6d 100755
--- a/test cases/common/72 ctarget dependency/gen1.py
+++ b/test cases/common/72 ctarget dependency/gen1.py
@@ -6,7 +6,7 @@ import time, sys
 # is missing.
 time.sleep(0.5)
 
-with open(sys.argv[1], 'r') as f:
+with open(sys.argv[1]) as f:
     contents = f.read()
 with open(sys.argv[2], 'w') as f:
     f.write(contents)
diff --git a/test cases/common/72 ctarget dependency/gen2.py b/test cases/common/72 ctarget dependency/gen2.py
index b087b02..dc6525b 100755
--- a/test cases/common/72 ctarget dependency/gen2.py
+++ b/test cases/common/72 ctarget dependency/gen2.py
@@ -6,5 +6,5 @@ from glob import glob
 files = glob(os.path.join(sys.argv[1], '*.tmp'))
 assert(len(files) == 1)
 
-with open(files[0], 'r') as ifile, open(sys.argv[2], 'w') as ofile:
+with open(files[0]) as ifile, open(sys.argv[2], 'w') as ofile:
     ofile.write(ifile.read())
diff --git a/test cases/common/96 manygen/subdir/manygen.py b/test cases/common/96 manygen/subdir/manygen.py
index 32ea63c..c40cc2e 100755
--- a/test cases/common/96 manygen/subdir/manygen.py
+++ b/test cases/common/96 manygen/subdir/manygen.py
@@ -1,6 +1,5 @@
 #!/usr/bin/env python3
 
-from __future__ import print_function
 
 # Generates a static library, object file, source
 # file and a header file.
diff --git a/test cases/unit/11 cross prog/some_cross_tool.py b/test cases/unit/11 cross prog/some_cross_tool.py
index 4a473e2..6c01b1a 100755
--- a/test cases/unit/11 cross prog/some_cross_tool.py
+++ b/test cases/unit/11 cross prog/some_cross_tool.py
@@ -1,5 +1,4 @@
 #!/usr/bin/env python3
 
-from __future__ import print_function
 
 print('cross')
diff --git a/test cases/unit/11 cross prog/sometool.py b/test cases/unit/11 cross prog/sometool.py
index 2ac5680..06bcdc8 100755
--- a/test cases/unit/11 cross prog/sometool.py
+++ b/test cases/unit/11 cross prog/sometool.py
@@ -1,5 +1,4 @@
 #!/usr/bin/env python3
 
-from __future__ import print_function
 
 print('native')
diff --git a/test cases/windows/12 resources with custom targets/res/gen-res.py b/test cases/windows/12 resources with custom targets/res/gen-res.py
index 2feb02f..e5ef6b1 100755
--- a/test cases/windows/12 resources with custom targets/res/gen-res.py
+++ b/test cases/windows/12 resources with custom targets/res/gen-res.py
@@ -2,5 +2,5 @@
 
 import sys
 
-with open(sys.argv[1], 'r') as infile, open(sys.argv[2], 'w') as outfile:
+with open(sys.argv[1]) as infile, open(sys.argv[2], 'w') as outfile:
     outfile.write(infile.read().format(icon=sys.argv[3]))
diff --git a/tools/dircondenser.py b/tools/dircondenser.py
index 8da0ce2..b49d80f 100755
--- a/tools/dircondenser.py
+++ b/tools/dircondenser.py
@@ -54,7 +54,7 @@ def get_entries() -> T.List[T.Tuple[int, str]]:
     return entries
 
 def replace_source(sourcefile: str, replacements: T.List[T.Tuple[str, str]]) -> None:
-    with open(sourcefile, 'r') as f:
+    with open(sourcefile) as f:
         contents = f.read()
     for old_name, new_name in replacements:
         contents = contents.replace(old_name, new_name)
diff --git a/tools/regenerate_docs.py b/tools/regenerate_docs.py
index b9b994a..2765836 100755
--- a/tools/regenerate_docs.py
+++ b/tools/regenerate_docs.py
@@ -94,7 +94,7 @@ def get_commands_data(root_dir: Path) -> T.Dict[str, T.Any]:
         return out
 
     output = _get_meson_output(root_dir, ['--help'])
-    commands = set(c.strip() for c in re.findall(r'usage:(?:.+)?{((?:[a-z]+,*)+?)}', output, re.MULTILINE|re.DOTALL)[0].split(','))
+    commands = {c.strip() for c in re.findall(r'usage:(?:.+)?{((?:[a-z]+,*)+?)}', output, re.MULTILINE|re.DOTALL)[0].split(',')}
     commands.remove('help')
 
     cmd_data = dict()