Add colour to Python help

Author: hugovk

Lib/test/test_cmd_line.py

@@ -57,6 +57,7 @@ def verify_valid_flag(self, cmd_line):
         return out
 
     @support.cpython_only
+    @support.force_not_colorized
     def test_help(self):
         self.verify_valid_flag('-h')
         self.verify_valid_flag('-?')
@@ -68,6 +69,7 @@ def test_help(self):
         self.assertLess(len(lines), 50)
 
     @support.cpython_only
+    @support.force_not_colorized
     def test_help_env(self):
         out = self.verify_valid_flag('--help-env')
         self.assertIn(b'PYTHONHOME', out)
@@ -81,6 +83,7 @@ def test_help_env(self):
                              "env vars should be sorted alphabetically")
 
     @support.cpython_only
+    @support.force_not_colorized
     def test_help_xoptions(self):
         out = self.verify_valid_flag('--help-xoptions')
         self.assertIn(b'-X dev', out)
@@ -89,6 +92,7 @@ def test_help_xoptions(self):
                          "options should be sorted alphabetically")
 
     @support.cpython_only
+    @support.force_not_colorized
     def test_help_all(self):
         out = self.verify_valid_flag('--help-all')
         lines = out.splitlines()
@@ -100,6 +104,29 @@ def test_help_all(self):
         # but the rest should be ASCII-only
         b''.join(lines[1:]).decode('ascii')
 
+    @support.cpython_only
+    @support.force_colorized
+    def test_help_colorized(self):
+        rc, out, err = assert_python_ok("--help", FORCE_COLOR="1")
+        # Check ANSI color codes are present
+        self.assertIn(b'\x1b[', out)
+        # "usage:" heading in bold blue
+        self.assertIn(b'\x1b[1;34musage:\x1b[0m', out)
+        # Short option in bold green
+        self.assertIn(b'\x1b[1;32m-h\x1b[0m', out)
+        # Long option in bold cyan
+        self.assertIn(b'\x1b[1;36m--help-all\x1b[0m', out)
+        # Label in bold yellow
+        self.assertIn(b'\x1b[1;33mcmd\x1b[0m', out)
+        # Heading in bold blue
+        self.assertIn(b'\x1b[1;34mArguments:\x1b[0m', out)
+
+    @support.cpython_only
+    @support.force_not_colorized
+    def test_help_not_colorized(self):
+        rc, out, err = assert_python_ok("--help")
+        self.assertNotIn(b'\x1b[', out)
+
     def test_optimize(self):
         self.verify_valid_flag('-O')
         self.verify_valid_flag('-OO')
@@ -1063,6 +1090,7 @@ def test_argv0_normalization(self):
         self.assertEqual(proc.stdout.strip(), b'0')
 
     @support.cpython_only
+    @support.force_not_colorized
     def test_parsing_error(self):
         args = [sys.executable, '-I', '--unknown-option']
         proc = subprocess.run(args,