pylint: enable the bad_builtin checker

This finds uses of deny-listed functions, which defaults to map and
filter. These functions should be replaced by comprehensions in
idiomatic python because:
    1. comprehensions are more heavily optimized and are often faster
    2. They avoid the need for lambdas in some cases, which make them
       faster
    3. you can do the equivalent in one statement rather than two, which
       is faster
    4. They're easier to read
    5. if you need a concrete instance (ie, a list) then you don't have
       to convert the iterator to a list afterwards

.pylintrc

@@ -1,5 +1,7 @@
 [MASTER]
 jobs=0
+load-plugins=
+    pylint.extensions.bad_builtin,
 
 [REPORTS]
 score=no

mesonbuild/backend/ninjabackend.py

@@ -209,8 +209,8 @@ class NinjaRule:
             return NinjaCommandArg(c)
 
         self.name = rule
-        self.command = list(map(strToCommandArg, command))  # includes args which never go into a rspfile
-        self.args = list(map(strToCommandArg, args))  # args which will go into a rspfile, if used
+        self.command = [strToCommandArg(c) for c in command]  # includes args which never go into a rspfile
+        self.args = [strToCommandArg(a) for a in args]  # args which will go into a rspfile, if used
         self.description = description
         self.deps = deps  # depstyle 'gcc' or 'msvc'
         self.depfile = depfile

mesonbuild/backend/xcodebackend.py

@@ -541,7 +541,7 @@ class XCodeBackend(backends.Backend):
         self.custom_aggregate_targets = {}
         self.build_all_tdep_id = self.gen_id()
         # FIXME: filter out targets that are not built by default.
-        target_dependencies = list(map(lambda t: self.pbx_dep_map[t], self.build_targets))
+        target_dependencies = [self.pbx_dep_map[t] for t in self.build_targets]
         custom_target_dependencies = [self.pbx_custom_dep_map[t] for t in self.custom_targets]
         aggregated_targets = []
         aggregated_targets.append((self.all_id, 'ALL_BUILD',

mesonbuild/cmake/common.py

@@ -111,7 +111,7 @@ def _flags_to_list(raw: str) -> T.List[str]:
         else:
             curr += i
     res += [curr]
-    res = list(filter(lambda x: len(x) > 0, res))
+    res = [r for r in res if len(r) > 0]
     return res
 
 def cmake_get_generator_args(env: 'Environment') -> T.List[str]:

mesonbuild/cmake/traceparser.py

@@ -747,7 +747,7 @@ class CMakeTraceParser:
             func = mo_file_line.group(4)
             args = mo_file_line.group(5)
             argl = args.split(' ')
-            argl = list(map(lambda x: x.strip(), argl))
+            argl = [a.strip() for a in argl]
 
             yield CMakeTraceLine(file, int(line), func, argl)
 

mesonbuild/dependencies/cmake.py

@@ -510,7 +510,7 @@ class CMakeDependency(ExternalDependency):
 
             # Try to use old style variables if no module is specified
             if len(libs) > 0:
-                self.compile_args = list(map(lambda x: f'-I{x}', incDirs)) + defs
+                self.compile_args = [f'-I{x}' for x in incDirs] + defs
                 self.link_args = []
                 for j in libs:
                     rtgt = resolve_cmake_trace_targets(j, self.traceparser, self.env, clib_compiler=self.clib_compiler)

mesonbuild/interpreter/interpreter.py

@@ -2555,7 +2555,7 @@ class Interpreter(InterpreterBase, HoldableObject):
                     mesonlib.do_conf_file(inputs_abs[0], ofile_abs, conf,
                                           fmt, file_encoding)
                 if missing_variables:
-                    var_list = ", ".join(map(repr, sorted(missing_variables)))
+                    var_list = ", ".join(repr(m) for m in sorted(missing_variables))
                     mlog.warning(
                         f"The variable(s) {var_list} in the input file '{inputs[0]}' are not "
                         "present in the given configuration data.", location=node)

mesonbuild/interpreter/interpreterobjects.py

@@ -81,7 +81,7 @@ def extract_search_dirs(kwargs: 'kwargs.ExtractSearchDirs') -> T.List[str]:
             continue
         if not d.is_absolute():
             raise InvalidCode(f'Search directory {d} is not an absolute path.')
-    return list(map(str, search_dirs))
+    return [str(s) for s in search_dirs]
 
 class FeatureOptionHolder(ObjectHolder[coredata.UserFeatureOption]):
     def __init__(self, option: coredata.UserFeatureOption, interpreter: 'Interpreter'):

mesonbuild/mcompile.py

@@ -190,11 +190,9 @@ def get_parsed_args_vs(options: 'argparse.Namespace', builddir: Path) -> T.Tuple
 
     if options.targets:
         intro_data = parse_introspect_data(builddir)
-        has_run_target = any(map(
-            lambda t:
-                get_target_from_intro_data(ParsedTargetName(t), builddir, intro_data)['type'] == 'run',
-            options.targets
-        ))
+        has_run_target = any(
+            get_target_from_intro_data(ParsedTargetName(t), builddir, intro_data)['type'] == 'run'
+            for t in options.targets)
 
         if has_run_target:
             # `run` target can't be used the same way as other targets on `vs` backend.

mesonbuild/minit.py

@@ -97,7 +97,7 @@ def autodetect_options(options: 'argparse.Namespace', sample: bool = False) -> N
             raise SystemExit('No recognizable source files found.\n'
                              'Run meson init in an empty directory to create a sample project.')
         options.srcfiles = srcfiles
-        print("Detected source files: " + ' '.join(map(str, srcfiles)))
+        print("Detected source files: " + ' '.join(str(s) for s in srcfiles))
     options.srcfiles = [Path(f) for f in options.srcfiles]
     if not options.language:
         for f in options.srcfiles:

mesonbuild/modules/external_project.py

@@ -191,7 +191,7 @@ class ExternalProject(NewExtensionModule):
             missing.update(missing_vars)
             out.append(arg)
         if missing:
-            var_list = ", ".join(map(repr, sorted(missing)))
+            var_list = ", ".join(repr(m) for m in sorted(missing))
             raise EnvironmentException(
                 f"Variables {var_list} in configure options are missing.")
         return out

mesonbuild/utils/universal.py

@@ -26,7 +26,7 @@ import abc
 import platform, subprocess, operator, os, shlex, shutil, re
 import collections
 from functools import lru_cache, wraps, total_ordering
-from itertools import tee, filterfalse
+from itertools import tee
 from tempfile import TemporaryDirectory, NamedTemporaryFile
 import typing as T
 import textwrap
@@ -1399,7 +1399,7 @@ def partition(pred: T.Callable[[_T], object], iterable: T.Iterable[_T]) -> T.Tup
     ([0, 2, 4, 6, 8], [1, 3, 5, 7, 9])
     """
     t1, t2 = tee(iterable)
-    return filterfalse(pred, t1), filter(pred, t2)
+    return (t for t in t1 if not pred(t)), (t for t in t2 if pred(t))
 
 
 def Popen_safe(args: T.List[str], write: T.Optional[str] = None,