[clang-tools-extra] c57b8ca - [clang-tidy] Provide fine control of color in run-clang-tidy

[Nathan James via cfe-commits]

Author: Kesavan Yogeswaran
Date: 2022-02-20T22:00:28Z
New Revision: c57b8ca721dd2e88ed96b7df65a518fdab738445

URL: https://github.com/llvm/llvm-project/commit/c57b8ca721dd2e88ed96b7df65a518fdab738445
DIFF: https://github.com/llvm/llvm-project/commit/c57b8ca721dd2e88ed96b7df65a518fdab738445.diff

LOG: [clang-tidy] Provide fine control of color in run-clang-tidy

D90110 modified the behavior of `run-clang-tidy` to always pass the
`--use-color` option to clang-tidy, which enabled colored diagnostics
output regardless of TTY status or .clang-tidy settings. This left the
user with no option to disable the colored output.

This presents an issue when trying to parse the output of run-clang-tidy
programmaticall, as the output is polluted with ANSI escape characters.

This PR fixes this issue in two ways:
1. It restores the default behavior of `run-clang-tidy` to let
   `clang-tidy` decide whether to color output. This allows the user to
   configure color via the `UseColor` option in a .clang-tidy file.
2. It adds mutually exclusive, optional `-use-color` and `-no-use-color`
   argument flags that let the user explicitly set the color option via
   the invocation.

After this change the default behavior of `run-clang-tidy` when no
.clang-tidy file is available is now to show no color, presumably
because `clang-tidy` detects that the output is being piped and defaults
to not showing colored output. This seems like an acceptable tradeoff
to respect .clang-tidy configurations, as users can still use the
`-use-color` option to explicitly enable color.

Fixes #49441 (50097 in Bugzilla)

Reviewed By: njames93

Differential Revision: https://reviews.llvm.org/D119562

Added: 
    

Modified: 
    clang-tools-extra/clang-tidy/tool/run-clang-tidy.py

Removed: 
    


################################################################################
diff  --git a/clang-tools-extra/clang-tidy/tool/run-clang-tidy.py b/clang-tools-extra/clang-tidy/tool/run-clang-tidy.py
index 090646c1b061b..fa98c217e2381 100755
--- a/clang-tools-extra/clang-tidy/tool/run-clang-tidy.py
+++ b/clang-tools-extra/clang-tidy/tool/run-clang-tidy.py
@@ -62,6 +62,21 @@
     import queue as queue
 
 
+def strtobool(val):
+  """Convert a string representation of truth to a bool following LLVM's CLI argument parsing."""
+
+  val = val.lower()
+  if val in ['', 'true', '1']:
+    return True
+  elif val in ['false', '0']:
+    return False
+
+  # Return ArgumentTypeError so that argparse does not substitute its own error message
+  raise argparse.ArgumentTypeError(
+    "'{}' is invalid value for boolean argument! Try 0 or 1.".format(val)
+  )
+
+
 def find_compilation_database(path):
   """Adjusts the directory until a compilation database is found."""
   result = './'
@@ -82,15 +97,20 @@ def make_absolute(f, directory):
 def get_tidy_invocation(f, clang_tidy_binary, checks, tmpdir, build_path,
                         header_filter, allow_enabling_alpha_checkers,
                         extra_arg, extra_arg_before, quiet, config,
-                        line_filter):
+                        line_filter, use_color):
   """Gets a command line for clang-tidy."""
-  start = [clang_tidy_binary, '--use-color']
+  start = [clang_tidy_binary]
   if allow_enabling_alpha_checkers:
     start.append('-allow-enabling-analyzer-alpha-checkers')
   if header_filter is not None:
     start.append('-header-filter=' + header_filter)
   if line_filter is not None:
     start.append('-line-filter=' + line_filter)
+  if use_color is not None:
+    if use_color:
+      start.append('--use-color')
+    else:
+      start.append('--use-color=false')
   if checks:
     start.append('-checks=' + checks)
   if tmpdir is not None:
@@ -168,7 +188,8 @@ def run_tidy(args, tmpdir, build_path, queue, lock, failed_files):
                                      tmpdir, build_path, args.header_filter,
                                      args.allow_enabling_alpha_checkers,
                                      args.extra_arg, args.extra_arg_before,
-                                     args.quiet, args.config, args.line_filter)
+                                     args.quiet, args.config, args.line_filter,
+                                     args.use_color)
 
     proc = subprocess.Popen(invocation, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
     output, err = proc.communicate()
@@ -231,6 +252,10 @@ def main():
                       'after applying fixes')
   parser.add_argument('-style', default='file', help='The style of reformat '
                       'code after applying fixes')
+  parser.add_argument('-use-color', type=strtobool, nargs='?', const=True,
+                      help='Use colors in diagnostics, overriding clang-tidy\'s'
+                      ' default behavior. This option overrides the \'UseColor'
+                      '\' option in .clang-tidy file, if any.')
   parser.add_argument('-p', dest='build_path',
                       help='Path used to read a compile command database.')
   parser.add_argument('-extra-arg', dest='extra_arg',
@@ -258,7 +283,8 @@ def main():
                                      None, build_path, args.header_filter,
                                      args.allow_enabling_alpha_checkers,
                                      args.extra_arg, args.extra_arg_before,
-                                     args.quiet, args.config, args.line_filter)
+                                     args.quiet, args.config, args.line_filter,
+                                     args.use_color)
     invocation.append('-list-checks')
     invocation.append('-')
     if args.quiet: