From c44f5b046b3f8e9a742c583880ae3a3f78828944 Mon Sep 17 00:00:00 2001 From: Samer Masterson Date: Wed, 8 Apr 2015 22:31:51 -0400 Subject: [PATCH] * lisp/eshell: Make backslash a no-op in front of normal chars Fixes: debbugs:8531 * lisp/eshell/esh-arg.el (eshell-parse-argument-hook): Update comment. (eshell-parse-backslash): Return escaped character after backslash if it is special. Otherwise, if the backslash is not in a quoted string, ignore the backslash and return the character after; if the backslash is in a quoted string, return the backslash and the character after. * test/automated/eshell.el (eshell-test/escape-nonspecial) (eshell-test/escape-nonspecial-unicode) (eshell-test/escape-nonspecial-quoted) (eshell-test/escape-special-quoted): Add tests for new `eshell-parse-backslash' behavior. --- lisp/eshell/esh-arg.el | 49 +++++++++++++++++----------------------- test/automated/eshell.el | 31 +++++++++++++++++++++++++ 2 files changed, 52 insertions(+), 28 deletions(-) diff --git a/lisp/eshell/esh-arg.el b/lisp/eshell/esh-arg.el index 5c7d7cae292..a5f697f037a 100644 --- a/lisp/eshell/esh-arg.el +++ b/lisp/eshell/esh-arg.el @@ -89,7 +89,7 @@ yield the values intended." (goto-char (match-end 0)) (eshell-finish-arg))))) - ;; backslash before a special character means escape it + ;; parse backslash and the character after 'eshell-parse-backslash ;; text beginning with ' is a literally quoted @@ -305,34 +305,27 @@ If the character is itself a backslash, it needs no escaping." (string ?\\ char))))) (defun eshell-parse-backslash () - "Parse a single backslash (\) character, which might mean escape. -It only means escape if the character immediately following is a -special character that is not itself a backslash." + "Parse a single backslash (\\) character and the character after. +If the character after the backslash is special, always ignore +the backslash and return the escaped character. + +Otherwise, if the backslash is not in quoted string, the +backslash is ignored and the character after is returned. If the +backslash is in a quoted string, the backslash and the character +after are both returned." (when (eq (char-after) ?\\) - (if (eshell-looking-at-backslash-return (point)) - (throw 'eshell-incomplete ?\\) - (if (and (not (eq (char-after (1+ (point))) ?\\)) - (if eshell-current-quoted - (memq (char-after (1+ (point))) - eshell-special-chars-inside-quoting) - (memq (char-after (1+ (point))) - eshell-special-chars-outside-quoting))) - (progn - (forward-char 2) - (list 'eshell-escape-arg - (char-to-string (char-before)))) - ;; allow \\ to mean a literal "\" character followed by a - ;; normal return, rather than a backslash followed by a line - ;; continuation (i.e., "\\ + \n" rather than "\ + \\n"). This - ;; is necessary because backslashes in Eshell are not special - ;; unless they either precede something special, or precede a - ;; backslash that precedes something special. (Mainly this is - ;; done to make using backslash on Windows systems more - ;; natural-feeling). - (if (eshell-looking-at-backslash-return (1+ (point))) - (forward-char)) - (forward-char) - "\\")))) + (when (eshell-looking-at-backslash-return (point)) + (throw 'eshell-incomplete ?\\)) + (forward-char 2) ; Move one char past the backslash. + ;; If the char is in a quote, backslash only has special meaning + ;; if it is escaping a special char. + (if eshell-current-quoted + (if (memq (char-before) eshell-special-chars-inside-quoting) + (list 'eshell-escape-arg (char-to-string (char-before))) + (concat "\\" (char-to-string (char-before)))) + (if (memq (char-before) eshell-special-chars-outside-quoting) + (list 'eshell-escape-arg (char-to-string (char-before))) + (char-to-string (char-before)))))) (defun eshell-parse-literal-quote () "Parse a literally quoted string. Nothing has special meaning!" diff --git a/test/automated/eshell.el b/test/automated/eshell.el index d51355fe5ca..81898db79a7 100644 --- a/test/automated/eshell.el +++ b/test/automated/eshell.el @@ -166,6 +166,37 @@ e.g. \"{(+ 1 2)} 3\" => 3" (eshell-command-result-p "+ 1 2; + $_ 4" "3\n6\n"))) +(ert-deftest eshell-test/escape-nonspecial () + "Test that \"\\c\" and \"c\" are equivalent when \"c\" is not a +special character." + (with-temp-eshell + (eshell-command-result-p "echo he\\llo" + "hello\n"))) + +(ert-deftest eshell-test/escape-nonspecial-unicode () + "Test that \"\\c\" and \"c\" are equivalent when \"c\" is a +unicode character (unicode characters are nonspecial by +definition)." + (with-temp-eshell + (eshell-command-result-p "echo Vid\\éos" + "Vidéos\n"))) + +(ert-deftest eshell-test/escape-nonspecial-quoted () + "Test that the backslash is preserved for escaped nonspecial +chars" + (with-temp-eshell + (eshell-command-result-p "echo \"h\\i\"" + ;; Backslashes are doubled for regexp. + "h\\\\i\n"))) + +(ert-deftest eshell-test/escape-special-quoted () + "Test that the backslash is not preserved for escaped special +chars" + (with-temp-eshell + (eshell-command-result-p "echo \"h\\\\i\"" + ;; Backslashes are doubled for regexp. + "h\\\\i\n"))) + (ert-deftest eshell-test/command-running-p () "Modeline should show no command running" (with-temp-eshell -- 2.39.2