Split console colourization into a separate function

Use it instead of making a direct call to mlog._windows_ansi().

mesonbuild/mesonlib.py

@@ -65,8 +65,7 @@ def git(cmd: T.List[str], workingdir: str, **kwargs) -> subprocess.CompletedProc
     # Sometimes git calls git recursively, such as `git submodule update
     # --recursive` which will be without the above workaround, so set the
     # console mode again just in case.
-    if platform.system().lower() == 'windows':
-        mlog._windows_ansi()
+    mlog.setup_console()
     return pc
 
 

mesonbuild/mlog.py

@@ -40,13 +40,15 @@ def _windows_ansi() -> bool:
     # original behavior
     return bool(kernel.SetConsoleMode(stdout, mode.value | 0x4) or os.environ.get('ANSICON'))
 
-try:
-    if platform.system().lower() == 'windows':
-        colorize_console = os.isatty(sys.stdout.fileno()) and _windows_ansi()  # type: bool
-    else:
-        colorize_console = os.isatty(sys.stdout.fileno()) and os.environ.get('TERM') != 'dumb'
-except Exception:
-    colorize_console = False
+def setup_console() -> bool:
+    try:
+        if platform.system().lower() == 'windows':
+            return os.isatty(sys.stdout.fileno()) and _windows_ansi()
+        return os.isatty(sys.stdout.fileno()) and os.environ.get('TERM') != 'dumb'
+    except Exception:
+        return False
+
+colorize_console = setup_console()
 log_dir = None               # type: T.Optional[str]
 log_file = None              # type: T.Optional[T.TextIO]
 log_fname = 'meson-log.txt'  # type: str