From 5c12fe09f7ac710b2c2f279e0faa04be8652db0f Mon Sep 17 00:00:00 2001 From: Jim Porter Date: Thu, 16 Sep 2021 14:32:17 -0700 Subject: [PATCH] Improve behavior of 'electric-pair-mode' in 'cc-mode' This ensures that quotes are paired correctly within comments, allows for insertion of quote pairs immediately before another quote, and allows inserting quote pairs within a string (thus splitting the string in two). * lisp/progmodes/cc-mode.el (c-electric-pair-inhibit-predicate): Inhibit insertion of paired quote in fewer cases. * test/lisp/electric-tests.el (define-electric-pair-test): Add 'c-mode' to list of modes to test by default. --- lisp/progmodes/cc-mode.el | 22 +++++++++++++++------- test/lisp/electric-tests.el | 5 ++++- 2 files changed, 19 insertions(+), 8 deletions(-) diff --git a/lisp/progmodes/cc-mode.el b/lisp/progmodes/cc-mode.el index 8b30241449..80137590c7 100644 --- a/lisp/progmodes/cc-mode.el +++ b/lisp/progmodes/cc-mode.el @@ -2549,18 +2549,26 @@ c-electric-pair-inhibit-predicate At the time of call, point is just after the newly inserted CHAR. -When CHAR is \", t will be returned unless the \" is marked with -a string fence syntax-table text property. For other characters, -the default value of `electric-pair-inhibit-predicate' is called -and its value returned. +When CHAR is \" and not within a comment, t will be returned if +the quotes on the current line are already balanced (i.e. if the +last \" is not marked with a string fence syntax-table text +property). For other cases, the default value of +`electric-pair-inhibit-predicate' is called and its value +returned. This function is the appropriate value of `electric-pair-inhibit-predicate' for CC Mode modes, which mark invalid strings with such a syntax table text property on the opening \" and the next unescaped end of line." - (if (eq char ?\") - (not (equal (get-text-property (1- (point)) 'c-fl-syn-tab) '(15))) - (funcall (default-value 'electric-pair-inhibit-predicate) char))) + (or (and (eq char ?\") + (not (memq (cadr (c-semi-pp-to-literal (1- (point)))) '(c c++))) + (let ((last-quote (save-match-data + (save-excursion + (goto-char (c-point 'eoll)) + (search-backward "\""))))) + (not (equal (c-get-char-property last-quote 'c-fl-syn-tab) + '(15))))) + (funcall (default-value 'electric-pair-inhibit-predicate) char))) ;; Support for C diff --git a/test/lisp/electric-tests.el b/test/lisp/electric-tests.el index 4e7cbf5419..5eec058ede 100644 --- a/test/lisp/electric-tests.el +++ b/test/lisp/electric-tests.el @@ -32,6 +32,9 @@ (require 'elec-pair) (require 'cl-lib) +;; When running tests in c-mode, use single-line comments (//). +(add-hook 'c-mode-hook (lambda () (c-toggle-comment-style -1))) + (defun call-with-saved-electric-modes (fn) (let ((saved-electric (if electric-pair-mode 1 -1)) (saved-layout (if electric-layout-mode 1 -1)) @@ -174,7 +177,7 @@ define-electric-pair-test expected-string expected-point bindings - (modes '(quote (ruby-mode js-mode python-mode))) + (modes '(quote (ruby-mode js-mode python-mode c-mode))) (test-in-comments t) (test-in-strings t) (test-in-code t) -- 2.25.1