more f-strings too complex to be caught by pyupgrade

mesonbuild/backend/xcodebackend.py

@@ -1565,7 +1565,7 @@ class XCodeBackend(backends.Backend):
                 pchs = [pch for pch in pchs if pch.endswith('.h') or pch.endswith('.hh') or pch.endswith('hpp')]
                 if pchs:
                     if len(pchs) > 1:
-                        mlog.warning('Unsupported Xcode configuration: More than 1 precompiled header found "{}". Target "{}" might not compile correctly.'.format(str(pchs), target.name))
+                        mlog.warning(f'Unsupported Xcode configuration: More than 1 precompiled header found "{pchs!s}". Target "{target.name}" might not compile correctly.')
                     relative_pch_path = os.path.join(target.get_subdir(), pchs[0]) # Path relative to target so it can be used with "$(PROJECT_DIR)"
                     settings_dict.add_item('GCC_PRECOMPILE_PREFIX_HEADER', 'YES')
                     settings_dict.add_item('GCC_PREFIX_HEADER', f'"$(PROJECT_DIR)/{relative_pch_path}"')

mesonbuild/cmake/traceparser.py

@@ -157,7 +157,7 @@ class CMakeTraceParser:
         # First load the trace (if required)
         if not self.requires_stderr():
             if not self.trace_file_path.exists and not self.trace_file_path.is_file():
-                raise CMakeException('CMake: Trace file "{}" not found'.format(str(self.trace_file_path)))
+                raise CMakeException(f'CMake: Trace file "{self.trace_file_path!s}" not found')
             trace = self.trace_file_path.read_text(errors='ignore', encoding='utf-8')
         if not trace:
             raise CMakeException('CMake: The CMake trace was not provided or is empty')
@@ -652,7 +652,7 @@ class CMakeTraceParser:
         if not args:
             mlog.error('Invalid preload.cmake script! At least one argument to `meson_ps_disabled_function` is expected')
             return
-        mlog.warning('The CMake function "{}" was disabled to avoid compatibility issues with Meson.'.format(args[0]))
+        mlog.warning(f'The CMake function "{args[0]}" was disabled to avoid compatibility issues with Meson.')
 
     def _lex_trace_human(self, trace: str) -> T.Generator[CMakeTraceLine, None, None]:
         # The trace format is: '<file>(<line>):  <func>(<args -- can contain \n> )\n'

mesonbuild/compilers/cpp.py

@@ -110,12 +110,11 @@ class CPPCompiler(CLikeCompiler, Compiler):
         # Check if it's a class or a template
         if extra_args is None:
             extra_args = []
-        fargs = {'prefix': prefix, 'header': hname, 'symbol': symbol}
-        t = '''{prefix}
-        #include <{header}>
+        t = f'''{prefix}
+        #include <{hname}>
         using {symbol};
         int main(void) {{ return 0; }}'''
-        return self.compiles(t.format(**fargs), env, extra_args=extra_args,
+        return self.compiles(t, env, extra_args=extra_args,
                              dependencies=dependencies)
 
     def _test_cpp_std_arg(self, cpp_std_value: str) -> bool:

mesonbuild/compilers/detect.py

@@ -548,15 +548,15 @@ def _detect_c_or_cpp_compiler(env: 'Environment', lang: str, for_machine: Machin
                 if version != 'unknown version':
                     break
             else:
-                m = 'Failed to detect MSVC compiler version: stderr was\n{!r}'
-                raise EnvironmentException(m.format(err))
+                m = f'Failed to detect MSVC compiler version: stderr was\n{err!r}'
+                raise EnvironmentException(m)
             cl_signature = lookat.split('\n')[0]
             match = re.search(r'.*(x86|x64|ARM|ARM64)([^_A-Za-z0-9]|$)', cl_signature)
             if match:
                 target = match.group(1)
             else:
-                m = 'Failed to detect MSVC compiler target architecture: \'cl /?\' output is\n{}'
-                raise EnvironmentException(m.format(cl_signature))
+                m = f'Failed to detect MSVC compiler target architecture: \'cl /?\' output is\n{cl_signature}'
+                raise EnvironmentException(m)
             cls = VisualStudioCCompiler if lang == 'c' else VisualStudioCPPCompiler
             linker = guess_win_linker(env, ['link'], cls, for_machine)
             return cls(
@@ -1049,8 +1049,8 @@ def detect_d_compiler(env: 'Environment', for_machine: MachineChoice) -> Compile
         # up to date language version at time (2016).
         if os.path.basename(exelist[-1]).startswith(('ldmd', 'gdmd')):
             raise EnvironmentException(
-                'Meson does not support {} as it is only a DMD frontend for another compiler.'
-                'Please provide a valid value for DC or unset it so that Meson can resolve the compiler by itself.'.format(exelist[-1]))
+                f'Meson does not support {exelist[-1]} as it is only a DMD frontend for another compiler.'
+                'Please provide a valid value for DC or unset it so that Meson can resolve the compiler by itself.')
         try:
             p, out = Popen_safe(exelist + ['--version'])[0:2]
         except OSError as e:

mesonbuild/compilers/fortran.py

@@ -222,9 +222,8 @@ class GnuFortranCompiler(GnuCompiler, FortranCompiler):
         __has_include which breaks with GCC-Fortran 10:
         https://github.com/mesonbuild/meson/issues/7017
         '''
-        fargs = {'prefix': prefix, 'header': hname}
-        code = '{prefix}\n#include <{header}>'
-        return self.compiles(code.format(**fargs), env, extra_args=extra_args,
+        code = f'{prefix}\n#include <{hname}>'
+        return self.compiles(code, env, extra_args=extra_args,
                              dependencies=dependencies, mode='preprocess', disable_cache=disable_cache)
 
 

mesonbuild/compilers/mixins/gnu.py

@@ -317,7 +317,7 @@ class GnuLikeCompiler(Compiler, metaclass=abc.ABCMeta):
         if linker not in {'gold', 'bfd', 'lld'}:
             raise mesonlib.MesonException(
                 'Unsupported linker, only bfd, gold, and lld are supported, '
-                'not {}.'.format(linker))
+                f'not {linker}.')
         return [f'-fuse-ld={linker}']
 
     def get_coverage_args(self) -> T.List[str]:

mesonbuild/compilers/mixins/islinker.py

@@ -90,8 +90,8 @@ class BasicLinkerIsCompilerMixin(Compiler):
             f'Linker {self.id} does not support allow undefined')
 
     def get_pie_link_args(self) -> T.List[str]:
-        m = 'Linker {} does not support position-independent executable'
-        raise mesonlib.EnvironmentException(m.format(self.id))
+        m = f'Linker {self.id} does not support position-independent executable'
+        raise mesonlib.EnvironmentException(m)
 
     def get_undefined_link_args(self) -> T.List[str]:
         return []

mesonbuild/coredata.py

@@ -55,9 +55,8 @@ _T = T.TypeVar('_T')
 class MesonVersionMismatchException(MesonException):
     '''Build directory generated with Meson version is incompatible with current version'''
     def __init__(self, old_version: str, current_version: str) -> None:
-        super().__init__('Build directory has been generated with Meson version {}, '
-                         'which is incompatible with the current version {}.'
-                         .format(old_version, current_version))
+        super().__init__(f'Build directory has been generated with Meson version {old_version}, '
+                         f'which is incompatible with the current version {current_version}.')
         self.old_version = old_version
         self.current_version = current_version
 
@@ -237,7 +236,7 @@ class UserArrayOption(UserOption[T.List[str]]):
             mlog.deprecation(msg)
         for i in newvalue:
             if not isinstance(i, str):
-                raise MesonException('String array element "{}" is not a string.'.format(str(newvalue)))
+                raise MesonException(f'String array element "{newvalue!s}" is not a string.')
         if self.choices:
             bad = [x for x in newvalue if x not in self.choices]
             if bad:
@@ -521,8 +520,7 @@ class CoreData:
     def sanitize_prefix(self, prefix):
         prefix = os.path.expanduser(prefix)
         if not os.path.isabs(prefix):
-            raise MesonException('prefix value {!r} must be an absolute path'
-                                 ''.format(prefix))
+            raise MesonException(f'prefix value {prefix!r} must be an absolute path')
         if prefix.endswith('/') or prefix.endswith('\\'):
             # On Windows we need to preserve the trailing slash if the
             # string is of type 'C:\' because 'C:' is not an absolute path.
@@ -904,7 +902,7 @@ class MachineFileParser():
             except MesonException:
                 raise EnvironmentException(f'Malformed value in machine file variable {entry!r}.')
             except KeyError as e:
-                raise EnvironmentException('Undefined constant {!r} in machine file variable {!r}.'.format(e.args[0], entry))
+                raise EnvironmentException(f'Undefined constant {e.args[0]!r} in machine file variable {entry!r}.')
             section[entry] = res
             self.scope[entry] = res
         return section
@@ -1007,9 +1005,9 @@ def load(build_dir: str) -> CoreData:
         raise MesonException(load_fail_msg)
     except (ModuleNotFoundError, AttributeError):
         raise MesonException(
-            "Coredata file {!r} references functions or classes that don't "
+            f"Coredata file {filename!r} references functions or classes that don't "
             "exist. This probably means that it was generated with an old "
-            "version of meson.".format(filename))
+            "version of meson.")
     if not isinstance(obj, CoreData):
         raise MesonException(load_fail_msg)
     if major_versions_differ(obj.version, version):
@@ -1070,7 +1068,7 @@ def parse_cmd_line_options(args: argparse.Namespace) -> None:
             if key in args.cmd_line_options:
                 cmdline_name = BuiltinOption.argparse_name_to_arg(name)
                 raise MesonException(
-                    'Got argument {0} as both -D{0} and {1}. Pick one.'.format(name, cmdline_name))
+                    f'Got argument {name} as both -D{name} and {cmdline_name}. Pick one.')
             args.cmd_line_options[key] = value
             delattr(args, name)
 

mesonbuild/dependencies/base.py

@@ -373,8 +373,8 @@ class ExternalDependency(Dependency, HasNativeKwarg):
                 mlog.log(*found_msg)
 
                 if self.required:
-                    m = 'Unknown version of dependency {!r}, but need {!r}.'
-                    raise DependencyException(m.format(self.name, self.version_reqs))
+                    m = f'Unknown version of dependency {self.name!r}, but need {self.version_reqs!r}.'
+                    raise DependencyException(m)
 
             else:
                 (self.is_found, not_found, found) = \

mesonbuild/dependencies/configtool.py

@@ -135,8 +135,7 @@ class ConfigToolDependency(ExternalDependency):
         if p.returncode != 0:
             if self.required:
                 raise DependencyException(
-                    'Could not generate {} for {}.\n{}'.format(
-                        stage, self.name, err))
+                    f'Could not generate {stage} for {self.name}.\n{err}')
             return []
         return split_args(out)
 

mesonbuild/dependencies/cuda.py

@@ -177,7 +177,7 @@ class CudaDependency(SystemDependency):
             else:
                 mlog.warning(f'Could not detect CUDA Toolkit version for {path}')
         except Exception as e:
-            mlog.warning('Could not detect CUDA Toolkit version for {}: {}'.format(path, str(e)))
+            mlog.warning(f'Could not detect CUDA Toolkit version for {path}: {e!s}')
 
         return '0.0'
 
@@ -208,7 +208,7 @@ class CudaDependency(SystemDependency):
                 if m:
                     return self._strip_patch_version(m.group(1))
         except Exception as e:
-            mlog.debug('Could not read CUDA Toolkit\'s version file {}: {}'.format(version_file_path, str(e)))
+            mlog.debug(f'Could not read CUDA Toolkit\'s version file {version_file_path}: {e!s}')
 
         return None
 

mesonbuild/dependencies/misc.py

@@ -188,8 +188,7 @@ class Python3DependencySystem(SystemDependency):
             elif pycc.startswith(('i686', 'i386')):
                 return '32'
             else:
-                mlog.log('MinGW Python built with unknown CC {!r}, please file'
-                         'a bug'.format(pycc))
+                mlog.log(f'MinGW Python built with unknown CC {pycc!r}, please file a bug')
                 return None
         elif pyplat == 'win32':
             return '32'
@@ -399,8 +398,8 @@ class ShadercDependency(SystemDependency):
                 self.is_found = True
 
                 if self.static and lib != static_lib:
-                    mlog.warning('Static library {!r} not found for dependency {!r}, may '
-                                 'not be statically linked'.format(static_lib, self.name))
+                    mlog.warning(f'Static library {static_lib!r} not found for dependency '
+                                 f'{self.name!r}, may not be statically linked')
 
                 break
 

mesonbuild/environment.py

@@ -352,9 +352,9 @@ def detect_cpu_family(compilers: CompilersDict) -> str:
             trial = 'ppc64'
 
     if trial not in known_cpu_families:
-        mlog.warning('Unknown CPU family {!r}, please report this at '
+        mlog.warning(f'Unknown CPU family {trial!r}, please report this at '
                      'https://github.com/mesonbuild/meson/issues/new with the '
-                     'output of `uname -a` and `cat /proc/cpuinfo`'.format(trial))
+                     'output of `uname -a` and `cat /proc/cpuinfo`')
 
     return trial
 

mesonbuild/interpreter/interpreter.py

@@ -786,8 +786,7 @@ external dependencies (including libraries) must go to "dependencies".''')
             cmd = exelist[0]
             prog = ExternalProgram(cmd, silent=True)
             if not prog.found():
-                raise InterpreterException('Program {!r} not found '
-                                           'or not executable'.format(cmd))
+                raise InterpreterException(f'Program {cmd!r} not found or not executable')
             cmd = prog
             expanded_args = exelist[1:]
         else:
@@ -799,8 +798,7 @@ external dependencies (including libraries) must go to "dependencies".''')
             search_dir = os.path.join(srcdir, self.subdir)
             prog = ExternalProgram(cmd, silent=True, search_dir=search_dir)
             if not prog.found():
-                raise InterpreterException('Program or command {!r} not found '
-                                           'or not executable'.format(cmd))
+                raise InterpreterException(f'Program or command {cmd!r} not found or not executable')
             cmd = prog
         for a in listify(cargs):
             if isinstance(a, str):
@@ -1407,8 +1405,7 @@ external dependencies (including libraries) must go to "dependencies".''')
                 search_dir = source_dir
                 extra_search_dirs = search_dirs
             else:
-                raise InvalidArguments('find_program only accepts strings and '
-                                       'files, not {!r}'.format(exename))
+                raise InvalidArguments(f'find_program only accepts strings and files, not {exename!r}')
             extprog = ExternalProgram(exename, search_dir=search_dir,
                                       extra_search_dirs=extra_search_dirs,
                                       silent=True)
@@ -1433,11 +1430,9 @@ external dependencies (including libraries) must go to "dependencies".''')
 
     def add_find_program_override(self, name, exe):
         if name in self.build.searched_programs:
-            raise InterpreterException('Tried to override finding of executable "%s" which has already been found.'
-                                       % name)
+            raise InterpreterException(f'Tried to override finding of executable "{name}" which has already been found.')
         if name in self.build.find_overrides:
-            raise InterpreterException('Tried to override executable "%s" which has already been overridden.'
-                                       % name)
+            raise InterpreterException(f'Tried to override executable "{name}" which has already been overridden.')
         self.build.find_overrides[name] = exe
 
     def notfound_program(self, args):
@@ -2186,9 +2181,9 @@ This will become a hard error in the future.''' % kwargs['input'], location=self
                 if confdata_useless:
                     ifbase = os.path.basename(inputs_abs[0])
                     mlog.warning('Got an empty configuration_data() object and found no '
-                                 'substitutions in the input file {!r}. If you want to '
+                                 f'substitutions in the input file {ifbase!r}. If you want to '
                                  'copy a file to the build dir, use the \'copy:\' keyword '
-                                 'argument added in 0.47.0'.format(ifbase), location=node)
+                                 'argument added in 0.47.0', location=node)
             else:
                 mesonlib.dump_conf_header(ofile_abs, conf.conf_data, output_format)
             conf.mark_used()
@@ -2432,12 +2427,12 @@ This will become a hard error in the future.''' % kwargs['input'], location=self
     def _add_global_arguments(self, node: mparser.FunctionNode, argsdict: T.Dict[str, T.List[str]],
                               args: T.List[str], kwargs: 'kwargs.FuncAddProjectArgs') -> None:
         if self.is_subproject():
-            msg = 'Function \'{}\' cannot be used in subprojects because ' \
+            msg = f'Function \'{node.func_name}\' cannot be used in subprojects because ' \
                   'there is no way to make that reliable.\nPlease only call ' \
                   'this if is_subproject() returns false. Alternatively, ' \
                   'define a variable that\ncontains your language-specific ' \
                   'arguments and add it to the appropriate *_args kwarg ' \
-                  'in each target.'.format(node.func_name)
+                  'in each target.'
             raise InvalidCode(msg)
         frozen = self.project_args_frozen or self.global_args_frozen
         self._add_arguments(node, argsdict, frozen, args, kwargs)
@@ -2452,9 +2447,9 @@ This will become a hard error in the future.''' % kwargs['input'], location=self
     def _add_arguments(self, node: mparser.FunctionNode, argsdict: T.Dict[str, T.List[str]],
                        args_frozen: bool, args: T.List[str], kwargs: 'kwargs.FuncAddProjectArgs') -> None:
         if args_frozen:
-            msg = 'Tried to use \'{}\' after a build target has been declared.\n' \
+            msg = f'Tried to use \'{node.func_name}\' after a build target has been declared.\n' \
                   'This is not permitted. Please declare all ' \
-                  'arguments before your targets.'.format(node.func_name)
+                  'arguments before your targets.'
             raise InvalidCode(msg)
 
         self._warn_about_builtin_args(args)

mesonbuild/interpreter/interpreterobjects.py

@@ -340,10 +340,10 @@ class ConfigurationDataObject(MutableInterpreterObject, MesonInterpreterObject):
             raise InterpreterException("Can not set values on configuration object that has been used.")
         name, val = args
         if not isinstance(val, (int, str)):
-            msg = 'Setting a configuration data value to {!r} is invalid, ' \
+            msg = f'Setting a configuration data value to {val!r} is invalid, ' \
                   'and will fail at configure_file(). If you are using it ' \
                   'just to store some values, please use a dict instead.'
-            mlog.deprecation(msg.format(val), location=self.current_node)
+            mlog.deprecation(msg, location=self.current_node)
         desc = kwargs.get('description', None)
         if not isinstance(name, str):
             raise InterpreterException("First argument to set must be a string.")

mesonbuild/interpreter/mesonmain.py

@@ -98,12 +98,12 @@ class MesonMain(MesonInterpreterObject):
                 new = True
             else:
                 raise InterpreterException(
-                    'Arguments to {} must be strings, Files, or CustomTargets, '
-                    'Indexes of CustomTargets'.format(name))
+                   f'Arguments to {name} must be strings, Files, or CustomTargets, '
+                    'Indexes of CustomTargets')
         if new:
             FeatureNew.single_use(
-                'Calling "{}" with File, CustomTaget, Index of CustomTarget, '
-                'Executable, or ExternalProgram'.format(name),
+                f'Calling "{name}" with File, CustomTaget, Index of CustomTarget, '
+                'Executable, or ExternalProgram',
                 '0.55.0', self.interpreter.subproject)
         return script_args
 

mesonbuild/interpreterbase/interpreterbase.py

@@ -675,13 +675,13 @@ The result of this is undefined and will become a hard error in a future Meson r
     @staticmethod
     def _get_one_string_posarg(posargs: T.List[TYPE_var], method_name: str) -> str:
         if len(posargs) > 1:
-            m = '{}() must have zero or one arguments'
-            raise InterpreterException(m.format(method_name))
+            m = f'{method_name}() must have zero or one arguments'
+            raise InterpreterException(m)
         elif len(posargs) == 1:
             s = posargs[0]
             if not isinstance(s, str):
-                m = '{}() argument must be a string'
-                raise InterpreterException(m.format(method_name))
+                m = f'{method_name}() argument must be a string'
+                raise InterpreterException(m)
             return s
         return None
 
@@ -820,8 +820,8 @@ The result of this is undefined and will become a hard error in a future Meson r
                     return self.evaluate_statement(fallback)
                 return fallback
             return obj[index]
-        m = 'Arrays do not have a method called {!r}.'
-        raise InterpreterException(m.format(method_name))
+        m = f'Arrays do not have a method called {method_name!r}.'
+        raise InterpreterException(m)
 
     @builtinMethodNoKwargs
     def dict_method_call(self,

mesonbuild/linkers/linkers.py

@@ -406,8 +406,8 @@ class DynamicLinker(metaclass=abc.ABCMeta):
         return []
 
     def has_multi_arguments(self, args: T.List[str], env: 'Environment') -> T.Tuple[bool, bool]:
-        m = 'Language {} does not support has_multi_link_arguments.'
-        raise mesonlib.EnvironmentException(m.format(self.id))
+        m = f'Language {self.id} does not support has_multi_link_arguments.'
+        raise mesonlib.EnvironmentException(m)
 
     def get_debugfile_name(self, targetfile: str) -> str:
         '''Name of debug file written out (see below)'''
@@ -432,8 +432,8 @@ class DynamicLinker(metaclass=abc.ABCMeta):
         # TODO: this really needs to take a boolean and return the args to
         # disable pie, otherwise it only acts to enable pie if pie *isn't* the
         # default.
-        m = 'Linker {} does not support position-independent executable'
-        raise mesonlib.EnvironmentException(m.format(self.id))
+        m = f'Linker {self.id} does not support position-independent executable'
+        raise mesonlib.EnvironmentException(m)
 
     def get_lto_args(self) -> T.List[str]:
         return []

mesonbuild/mcompile.py

@@ -38,10 +38,10 @@ def array_arg(value: str) -> T.List[str]:
 
 def validate_builddir(builddir: Path) -> None:
     if not (builddir / 'meson-private' / 'coredata.dat' ).is_file():
-        raise MesonException('Current directory is not a meson build directory: `{}`.\n'
+        raise MesonException(f'Current directory is not a meson build directory: `{builddir}`.\n'
                              'Please specify a valid build dir or change the working directory to it.\n'
                              'It is also possible that the build directory was generated with an old\n'
-                             'meson version. Please regenerate it in this case.'.format(builddir))
+                             'meson version. Please regenerate it in this case.')
 
 def get_backend_from_coredata(builddir: Path) -> str:
     """

mesonbuild/mesonlib/universal.py

@@ -258,11 +258,11 @@ def check_direntry_issues(direntry_array: T.Union[T.List[T.Union[str, bytes]], s
         for de in direntry_array:
             if is_ascii_string(de):
                 continue
-            mlog.warning(textwrap.dedent('''
-                You are using {!r} which is not a Unicode-compatible
-                locale but you are trying to access a file system entry called {!r} which is
+            mlog.warning(textwrap.dedent(f'''
+                You are using {e!r} which is not a Unicode-compatible
+                locale but you are trying to access a file system entry called {de!r} which is
                 not pure ASCII. This may cause problems.
-                '''.format(e, de)), file=sys.stderr)
+                '''), file=sys.stderr)
 
 
 # Put this in objects that should not get dumped to pickle files
@@ -330,11 +330,11 @@ class FileMode:
             return -1
         eg = 'rwxr-xr-x'
         if not isinstance(perms_s, str):
-            msg = 'Install perms must be a string. For example, {!r}'
-            raise MesonException(msg.format(eg))
+            msg = f'Install perms must be a string. For example, {eg!r}'
+            raise MesonException(msg)
         if len(perms_s) != 9 or not cls.symbolic_perms_regex.match(perms_s):
-            msg = 'File perms {!r} must be exactly 9 chars. For example, {!r}'
-            raise MesonException(msg.format(perms_s, eg))
+            msg = f'File perms {perms_s!r} must be exactly 9 chars. For example, {eg!r}'
+            raise MesonException(msg)
         perms = 0
         # Owner perms
         if perms_s[0] == 'r':
@@ -1126,9 +1126,9 @@ def do_replacement(regex: T.Pattern[str], line: str, variable_format: str,
                 elif isinstance(var, int):
                     var_str = str(var)
                 else:
-                    msg = 'Tried to replace variable {!r} value with ' \
-                          'something other than a string or int: {!r}'
-                    raise MesonException(msg.format(varname, var))
+                    msg = f'Tried to replace variable {varname!r} value with ' \
+                          f'something other than a string or int: {var!r}'
+                    raise MesonException(msg)
             else:
                 missing_variables.add(varname)
             return var_str
@@ -1227,7 +1227,7 @@ def do_conf_file(src: str, dst: str, confdata: 'ConfigurationData', variable_for
         with open(src, encoding=encoding, newline='') as f:
             data = f.readlines()
     except Exception as e:
-        raise MesonException('Could not read input file {}: {}'.format(src, str(e)))
+        raise MesonException(f'Could not read input file {src}: {e!s}')
 
     (result, missing_variables, confdata_useless) = do_conf_str(src, data, confdata, variable_format, encoding)
     dst_tmp = dst + '~'
@@ -1235,7 +1235,7 @@ def do_conf_file(src: str, dst: str, confdata: 'ConfigurationData', variable_for
         with open(dst_tmp, 'w', encoding=encoding, newline='') as f:
             f.writelines(result)
     except Exception as e:
-        raise MesonException('Could not write output file {}: {}'.format(dst, str(e)))
+        raise MesonException(f'Could not write output file {dst}: {e!s}')
     shutil.copymode(src, dst_tmp)
     replace_if_different(dst, dst_tmp)
     return missing_variables, confdata_useless
@@ -1451,15 +1451,15 @@ def _substitute_values_check_errors(command: T.List[str], values: T.Dict[str, st
         # Error out if any input-derived templates are present in the command
         match = iter_regexin_iter(inregex, command)
         if match:
-            m = 'Command cannot have {!r}, since no input files were specified'
-            raise MesonException(m.format(match))
+            m = f'Command cannot have {match!r}, since no input files were specified'
+            raise MesonException(m)
     else:
         if len(values['@INPUT@']) > 1:
             # Error out if @PLAINNAME@ or @BASENAME@ is present in the command
             match = iter_regexin_iter(inregex[1:], command)
             if match:
-                raise MesonException('Command cannot have {!r} when there is '
-                                     'more than one input file'.format(match))
+                raise MesonException(f'Command cannot have {match!r} when there is '
+                                     'more than one input file')
         # Error out if an invalid @INPUTnn@ template was specified
         for each in command:
             if not isinstance(each, str):