vim-patch:632fd8b: runtime(python): Highlight built-in constants in Python

Also add syntax tests for those newly constants.

closes: vim/vim#17788
closes: vim/vim#18922

https://github.com/vim/vim/commit/632fd8bb968b029d0a7c40a00101008ea5200b91

Co-authored-by: Rob B <github@0x7e.net>

runtime/doc/syntax.txt

@@ -2732,7 +2732,7 @@ Pascal.  Use this if you don't use assembly and Pascal: >
 
 PYTHON							*ft-python-syntax*
 
-There are six options to control Python syntax highlighting.
+There are seven options to control Python syntax highlighting.
 
 For highlighted numbers: >
 	:let python_no_number_highlight = 1
@@ -2752,14 +2752,17 @@ The first option implies the second one.
 For highlighted trailing whitespace and mix of spaces and tabs: >
 	:let python_space_error_highlight = 1
 
+For highlighted built-in constants distinguished from other keywords:
+	:let python_constant_highlight = 1
+
 If you want all possible Python highlighting: >
 	:let python_highlight_all = 1
-This has the same effect as setting python_space_error_highlight and
-unsetting all the other ones.
+This has the same effect as setting python_space_error_highlight,
+python_constant_highlight and unsetting all the other ones.
 
 If you use Python 2 or straddling code (Python 2 and 3 compatible),
 you can enforce the use of an older syntax file with support for
-Python 2 and up to Python 3.5.  >
+Python 2 and up to Python 3.5. >
 	:let python_use_python2_syntax = 1
 This option will exclude all modern Python 3.6 or higher features.
 

runtime/syntax/python.vim

@@ -4,6 +4,7 @@
 " Last Change:	2025 Sep 08
 " 2025 Sep 25 by Vim Project: fix wrong type highlighting #18394
 " 2025 Dec 03 by Vim Project: highlight t-strings #18679
+" 2026 Jan 26 by Vim Project: highlight constants #18922
 " Credits:	Neil Schemenauer <nas@python.ca>
 "		Dmitry Vasiliev
 "		Rob B
@@ -34,6 +35,7 @@
 "   let python_no_exception_highlight = 1
 "   let python_no_number_highlight = 1
 "   let python_space_error_highlight = 1
+"   let python_constant_highlight = 1
 "
 " All the options above can be switched on together.
 "
@@ -85,6 +87,7 @@ if exists("python_highlight_all")
     unlet python_no_number_highlight
   endif
   let python_space_error_highlight = 1
+  let python_constant_highlight = 1
 endif
 
 " Keep Python keywords in alphabetical order inside groups for easy
@@ -97,7 +100,8 @@ endif
 "
 " python3 -c 'import keyword, pprint; pprint.pprint(keyword.kwlist + keyword.softkwlist, compact=True)'
 "
-syn keyword pythonStatement	False None True
+syn keyword pythonBoolean	False True
+syn keyword pythonConstant	None
 syn keyword pythonStatement	as assert break continue del global
 syn keyword pythonStatement	lambda nonlocal pass return with yield
 syn keyword pythonStatement	class nextgroup=pythonClass skipwhite
@@ -296,8 +300,8 @@ endif
 if !exists("python_no_builtin_highlight")
   " built-in constants
   " 'False', 'True', and 'None' are also reserved words in Python 3
-  syn keyword pythonBuiltin	False True None
-  syn keyword pythonBuiltin	NotImplemented Ellipsis __debug__
+  syn keyword pythonBoolean	False True
+  syn keyword pythonConstant	None NotImplemented Ellipsis __debug__
   " constants added by the `site` module
   syn keyword pythonBuiltin	quit exit copyright credits license
   " built-in functions
@@ -391,6 +395,8 @@ endif
 syn sync match pythonSync grouphere NONE "^\%(def\|class\|async\s\+def\)\s\+\h\w*\s*[(:]"
 
 " The default highlight links.  Can be overridden later.
+hi def link pythonBoolean		Statement
+hi def link pythonConstant		Statement
 hi def link pythonStatement		Statement
 hi def link pythonConditional		Conditional
 hi def link pythonRepeat		Repeat
@@ -421,6 +427,8 @@ if !exists("python_no_number_highlight")
   hi def link pythonNumber		Number
 endif
 if !exists("python_no_builtin_highlight")
+  hi! def link pythonBoolean		Function
+  hi! def link pythonConstant		Function
   hi def link pythonBuiltin		Function
   hi def link pythonEllipsis		pythonBuiltin
 endif
@@ -434,6 +442,10 @@ if !exists("python_no_doctest_highlight")
   hi def link pythonDoctest		Special
   hi def link pythonDoctestValue	Define
 endif
+if exists("python_constant_highlight")
+  hi! def link pythonBoolean		Boolean
+  hi! def link pythonConstant		Constant
+endif
 
 let b:current_syntax = "python"