bug#70657: [PATCH] Add go-ts-mode font-locking for function var decls

[Noah Peart <noah.v.peart@gmail.com>]

[-- Attachment #1.1: Type: text/plain, Size: 1451 bytes --]

Tags: patch


Adds font-locking for functions in go-ts-mode declared in var specs.

Currently, all the identifiers in var specs are given
font-lock-variable-name-face font-locking.

This patch adds a rule to give identifiers in var specs
font-lock-function-name-face when they are function types.

For example, the following test is included in the patch, showing where
font-lock-function-name is applied:

var x, y, z int
//    ^ font-lock-variable-name-face
//        ^ font-lock-variable-name-face
//                ^ font-lock-type-face
var foo, bar func(x int) int
//     ^ font-lock-function-name-face
//             ^ font-lock-function-name-face
//                         ^ font-lock-variable-name-face
//                             ^ font-lock-type-face
//                                   ^ font-lock-type-face


In GNU Emacs 30.0.50 (build 1, x86_64-pc-linux-gnu, GTK+ Version
3.24.33, cairo version 1.16.0) of 2024-04-29 built on noah-X580VD
Repository revision: 3000edc6179dfe0b5f24ae2e472826530809dfd1
Repository branch: master
Windowing system distributor 'The X.Org Foundation', version 11.0.12101004
System Description: Ubuntu 22.04.4 LTS

Configured using:
 'configure --prefix=/usr/local --with-modules --with-tree-sitter
--with-threads --with-x-toolkit=gtk3 --with-xwidgets --with-gnutls
--with-json --with-mailutils --with-jpeg --with-png --with-rsvg
--with-tiff --with-xml2 --with-xpm --with-imagemagick CC=gcc-12
CXX=gcc-12'

[-- Attachment #1.2: Type: text/html, Size: 1678 bytes --]

[-- Attachment #2: 0001-Add-go-ts-mode-font-locking-for-function-var-decls.patch --]
[-- Type: text/x-patch, Size: 2977 bytes --]

From f5825cb56b847512103bf441fff05d05474a512c Mon Sep 17 00:00:00 2001
From: Noah Peart <noah.v.peart@gmail.com>
Date: Mon, 29 Apr 2024 16:14:43 -0700
Subject: [PATCH] Add go-ts-mode font-locking for function var decls

* lisp/progmodes/go-ts-mode.el (go-ts-mode--font-lock-settings):
Add font-locking rule for go-ts-mode functions declared in
var_specs.
* test/lisp/progmodes/go-ts-mode-resources/font-lock.go: New file
with font-locking tests for go-ts-mode.
* test/lisp/progmodes/go-ts-mode-tests.el: Add go-ts-mode
font-locking tests.
---
 lisp/progmodes/go-ts-mode.el                          |  3 +++
 test/lisp/progmodes/go-ts-mode-resources/font-lock.go | 11 +++++++++++
 test/lisp/progmodes/go-ts-mode-tests.el               |  6 ++++++
 3 files changed, 20 insertions(+)
 create mode 100644 test/lisp/progmodes/go-ts-mode-resources/font-lock.go

diff --git a/lisp/progmodes/go-ts-mode.el b/lisp/progmodes/go-ts-mode.el
index aef224ab3fa..9c38985ff4e 100644
--- a/lisp/progmodes/go-ts-mode.el
+++ b/lisp/progmodes/go-ts-mode.el
@@ -179,6 +179,9 @@ go-ts-mode--font-lock-settings
       left: (expression_list
              (identifier) @font-lock-variable-name-face
              ("," (identifier) @font-lock-variable-name-face)*))
+     (var_spec name: (identifier) @font-lock-function-name-face
+               ("," name: (identifier) @font-lock-function-name-face)*
+               type: (function_type))
      (var_spec name: (identifier) @font-lock-variable-name-face
                ("," name: (identifier) @font-lock-variable-name-face)*))
 
diff --git a/test/lisp/progmodes/go-ts-mode-resources/font-lock.go b/test/lisp/progmodes/go-ts-mode-resources/font-lock.go
new file mode 100644
index 00000000000..8d8656f96e7
--- /dev/null
+++ b/test/lisp/progmodes/go-ts-mode-resources/font-lock.go
@@ -0,0 +1,11 @@
+package main
+var x, y, z int
+//  ^ font-lock-variable-name-face
+//     ^ font-lock-variable-name-face
+//           ^ font-lock-type-face
+var foo, bar func(x int) int
+//   ^ font-lock-function-name-face
+//        ^ font-lock-function-name-face
+//                ^ font-lock-variable-name-face
+//                    ^ font-lock-type-face
+//                        ^ font-lock-type-face
diff --git a/test/lisp/progmodes/go-ts-mode-tests.el b/test/lisp/progmodes/go-ts-mode-tests.el
index fd9b57e8691..761238e60a6 100644
--- a/test/lisp/progmodes/go-ts-mode-tests.el
+++ b/test/lisp/progmodes/go-ts-mode-tests.el
@@ -20,6 +20,7 @@
 ;;; Code:
 
 (require 'ert)
+(require 'ert-font-lock)
 (require 'ert-x)
 (require 'treesit)
 
@@ -27,5 +28,10 @@ go-ts-mode-test-indentation
   (skip-unless (treesit-ready-p 'go))
   (ert-test-erts-file (ert-resource-file "indent.erts")))
 
+(ert-deftest go-ts-test-font-lock ()
+  (skip-unless (treesit-ready-p 'go))
+  (let ((treesit-font-lock-level 4))
+    (ert-font-lock-test-file (ert-resource-file "font-lock.go") 'go-ts-mode)))
+
 (provide 'go-ts-mode-tests)
 ;;; go-ts-mode-tests.el ends here
-- 
2.34.1