Commit: runtime(syntax-tests): Rename test files on demand

[Christian Brabandt]

runtime(syntax-tests): Rename test files on demand

Commit: https://github.com/vim/vim/commit/ad8d21b14a107eb9ac438a93ed10a8e2be258219
Author: Aliaksei Budavei <0x00...@gmail.com>
Date: Sat Jun 13 18:45:58 2026 +0000

runtime(syntax-tests): Rename test files on demand

The current scheme for naming syntax plugin tests expects
a filetype name prefix and an associated filename extension.
However, many configurational filetypes, e.g. Gitignore,
lack any established filename extension. Factor out the
available file-renaming routine and offer a convenience
function to work around this limitation.

For example, put in a VIM_TEST_SETUP aware context:
------------------------------------------------------------
call DeferRenamingTestFileTo('.gitignore')
------------------------------------------------------------

closes: #20482

Signed-off-by: Aliaksei Budavei <0x00...@gmail.com>
Signed-off-by: Christian Brabandt <c...@256bit.org>

diff --git a/runtime/syntax/testdir/README.txt b/runtime/syntax/testdir/README.txt
index bd3730435..ecc023ac0 100644
--- a/runtime/syntax/testdir/README.txt
+++ b/runtime/syntax/testdir/README.txt
@@ -26,9 +26,12 @@ Creating a syntax plugin test
-----------------------------

Create a source file in the language you want to test in the "input"
-directory. Use the filetype name as the base and a file name extension
+directory. Use the filetype name as the base and a filename extension
matching the filetype. Let's use Java as an example. The file would then be
-"input/java.java".
+"input/java.java". As another example, consider Gitignore. Since there is no
+established filename extension for this filetype, use the filetype name for
+its base AND filename extension, "input/gitignore.gitignore", as the first
+step.

Make sure to include some interesting constructs with plenty of complicated
highlighting. Optionally, pre-configure the testing environment by including
@@ -48,6 +51,10 @@ Continuing the Java example:
// VIM_TEST_SETUP let g:java_minlines = 5
class Test { }

+Continuing the Gitignore example, give the file a valid name as the last step:
+
+ # VIM_TEST_SETUP call DeferRenamingTestFileTo('.gitignore')
+
As an alternative, setup commands can be included in an external Vim script
file in the "input/setup" directory. This script file must have the same base
name as the input file.
diff --git a/runtime/syntax/testdir/input/setup/java_module_info.vim b/runtime/syntax/testdir/input/setup/java_module_info.vim
index 2711c1a9a..73f812890 100644
--- a/runtime/syntax/testdir/input/setup/java_module_info.vim
+++ b/runtime/syntax/testdir/input/setup/java_module_info.vim
@@ -1,30 +1,3 @@
-vim9script
-
-# Test filenames are required to begin with the filetype name prefix,
-# whereas the name of a Java module declaration must be "module-info".
-const name_a: string = 'input/java_module_info.java'
-const name_b: string = 'input/module-info.java'
-
-def ChangeFilename()
- exec 'saveas! ' .. name_b
-enddef
-
-def RestoreFilename()
- exec 'saveas! ' .. name_a
- delete(name_b)
-enddef
-
-autocmd_add([{
- replace: true,
- group: 'java_syntax_tests',
- event: 'BufEnter',
- pattern: name_a,
- cmd: 'ChangeFilename()',
- once: true,
-}, {
- group: 'java_syntax_tests',
- event: ['BufLeave', 'ExitPre'],
- pattern: name_b,
- cmd: 'RestoreFilename()',
- once: true,
-}])
+" Test filenames are required to begin with the filetype name prefix,
+" whereas the name of a Java module declaration must be "module-info".
+call DeferRenamingTestFileTo('module-info.java')
diff --git a/runtime/syntax/testdir/runtest.vim b/runtime/syntax/testdir/runtest.vim
index b3a6612b7..86fbf0e06 100644
--- a/runtime/syntax/testdir/runtest.vim
+++ b/runtime/syntax/testdir/runtest.vim
@@ -253,6 +253,8 @@ func RunTest()
" Track the cursor progress through a syntax test file so that any
" degenerate input can be reported. Each file will have its own cursor.
let s:cursor = 1
+ " Give a new name to a file-associated buffer on demand.
+ let s:new_fname = ''

" extra info for shell variables
func ShellInfo()
@@ -294,14 +296,50 @@ func RunTest()
exe substitute(getline(lnum), '\C.*\<VIM_TEST_SETUP\>', '', '')
endfor
call cursor(1, 1)
+ let [old_name, new_name] = s:ResolveFilenames()
+ call s:ChangeFilenameTo(new_name)
" BEGIN [runtime/defaults.vim]
" Also, disable italic highlighting to avoid issues on some terminals.
set display=lastline ruler scrolloff=5 t_ZH= t_ZR=
syntax on
" END [runtime/defaults.vim]
+ call s:RestoreFilename(new_name, old_name)
redraw!
endfunc

+ def s:ChangeFilenameTo(name: string)
+ if !empty(name)
+ exe 'saveas! ' .. name
+ endif
+ enddef
+
+ def s:RestoreFilename(new_name: string, old_name: string)
+ if !empty(new_name) && !empty(old_name)
+ exe 'saveas! ' .. old_name
+ delete(new_name)
+ endif
+ enddef
+
+ def s:ResolveFilenames(): tuple<string, string>
+ if !empty(new_fname)
+ const old_name: string = fnamemodify(bufname(), ':.')
+ # Get a platform-independent pathname prefix, cf. "expand('%:p:h') .. '/'".
+ const new_name: string = strpart(
+ old_name,
+ 0,
+ strridx(old_name, fnamemodify(bufname(), ':t'))) ..
+ new_fname
+ return (old_name, new_name)
+ else
+ return ("", "")
+ endif
+ enddef
+
+ def DeferRenamingTestFileTo(name: string)
+ # Strip any leading pathname and mask the filenames of '.' and '..'.
+ new_fname = substitute(fnamemodify(name, ':t'), '^\.\.\=$', '', '')
+ enddef
+
def s:AssertCursorForwardProgress(): bool
const curnum: number = line('.')
if curnum <= cursor