[COMMIT PROG-MODES] Added go-mode.el

APPROVE COMMIT NOTE: This patch has been committed. # HG changeset patch # User Mats Lidell <matsl(a)xemacs.org&gt; # Date 1336937625 -7200 # Node ID a246dff1f05567a1054fc4d870c9f7ea6db09705 # Parent 9a5e5e7332618c86410233a50441d7a58cc62848 Added go-mode.el diff -r 9a5e5e733261 -r a246dff1f055 ChangeLog --- a/ChangeLog Fri Dec 23 11:41:10 2011 -0500 +++ b/ChangeLog Sun May 13 21:33:45 2012 +0200 ＠＠ -1,3 +1,8 ＠＠ +2012-05-13 Mats Lidell <matsl(a)xemacs.org&gt; + + * prog-modes.texi (go-mode): New mode for Go source. + * go-mode.el: New. + 2011-12-22 Vin Shelton <acs(a)xemacs.org&gt; * verilog-mode.el (verilog-mode-version): diff -r 9a5e5e733261 -r a246dff1f055 Makefile --- a/Makefile Fri Dec 23 11:41:10 2011 -0500 +++ b/Makefile Sun May 13 21:33:45 2012 +0200 ＠＠ -34,7 +34,7 ＠＠ postscript.elc prolog.elc rexx-mode.elc simula.elc \ sql.elc tcl.elc teco.elc verilog-mode.elc vrml-mode.elc p4.elc \ old-c-mode.elc php-mode.elc javascript-mode.elc \ - rpm-spec-mode.elc uil-mode.elc + rpm-spec-mode.elc uil-mode.elc go-mode.elc STANDARD_DOCS = t diff -r 9a5e5e733261 -r a246dff1f055 go-mode.el --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/go-mode.el Sun May 13 21:33:45 2012 +0200 ＠＠ -0,0 +1,860 ＠＠ +;;; go-mode.el --- Major mode for the Go programming language + +;; Copyright (c) 2012 The Go Authors. All rights reserved. + +;; Redistribution and use in source and binary forms, with or without +;; modification, are permitted provided that the following conditions are +;; met: + +;; * Redistributions of source code must retain the above copyright +;; notice, this list of conditions and the following disclaimer. +;; * Redistributions in binary form must reproduce the above +;; copyright notice, this list of conditions and the following disclaimer +;; in the documentation and/or other materials provided with the +;; distribution. +;; * Neither the name of Google Inc. nor the names of its +;; contributors may be used to endorse or promote products derived from +;; this software without specific prior written permission. + +;; THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +;; "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +;; LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +;; A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +;; OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +;; SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +;; LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +;; DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +;; THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +;; (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +;; OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +;;; Synced up with: upstream go-mode.el 13182:9d6693456f93 + +;;; Commentary: + +;; For installation instructions, see go-mode-load.el + +;;; To do: + +;; * Indentation is *almost* identical to gofmt +;; ** We think struct literal keys are labels and outdent them +;; ** We disagree on the indentation of function literals in arguments +;; ** There are bugs with the close brace of struct literals +;; * Highlight identifiers according to their syntactic context: type, +;; variable, function call, or tag +;; * Command for adding an import +;; ** Check if it's already there +;; ** Factor/unfactor the import line +;; ** Alphabetize +;; * Remove unused imports +;; ** This is hard, since I have to be aware of shadowing to do it +;; right +;; * Format region using gofmt + +;;; Code: + +(eval-when-compile (require 'cl)) + +(defvar go-mode-syntax-table + (let ((st (make-syntax-table))) + ;; Add _ to :word: character class + (modify-syntax-entry ?_ "w" st) + + ;; Operators (punctuation) + (modify-syntax-entry ?+ "." st) + (modify-syntax-entry ?- "." st) + (modify-syntax-entry ?* ". 23" st) ; also part of comments + (modify-syntax-entry ?/ (if (featurep 'xemacs) ". 1456" ". 124b") st) ; ditto + (modify-syntax-entry ?% "." st) + (modify-syntax-entry ?& "." st) + (modify-syntax-entry ?| "." st) + (modify-syntax-entry ?^ "." st) + (modify-syntax-entry ?! "." st) + (modify-syntax-entry ?= "." st) + (modify-syntax-entry ?< "." st) + (modify-syntax-entry ?> "." st) + + ;; Strings and comments are font-locked separately. + (modify-syntax-entry ?\" "." st) + (modify-syntax-entry ?\' "." st) + (modify-syntax-entry ?` "." st) + (modify-syntax-entry ?\\ "." st) + + ;; Newline is a comment-ender. + (modify-syntax-entry ?\n "> b" st) + + st) + "Syntax table for Go mode.") + +(defvar go-mode-keywords + '("break" "default" "func" "interface" "select" + "case" "defer" "go" "map" "struct" + "chan" "else" "goto" "package" "switch" + "const" "fallthrough" "if" "range" "type" + "continue" "for" "import" "return" "var") + "All keywords in the Go language. Used for font locking and +some syntax analysis.") + +(defvar go-mode-font-lock-keywords + (let ((builtins '("append" "cap" "close" "complex" "copy" "delete" "imag" "len" + "make" "new" "panic" "print" "println" "real" "recover")) + (constants '("nil" "true" "false" "iota")) + (type-name "\\s *\\(?:[*(]\\s *\\)*\\(?:\\w+\\s *\\.\\s *\\)?\\(\\w+\\)") + ) + `((go-mode-font-lock-cs-comment 0 font-lock-comment-face t) + (go-mode-font-lock-cs-string 0 font-lock-string-face t) + (,(regexp-opt go-mode-keywords 'words) . font-lock-keyword-face) + (,(regexp-opt builtins 'words) . font-lock-builtin-face) + (,(regexp-opt constants 'words) . font-lock-constant-face) + ;; Function names in declarations + ("\\<func\\>\\s *\\(\\w+\\)" 1 font-lock-function-name-face) + ;; Function names in methods are handled by function call pattern + ;; Function names in calls + ;; XXX Doesn't match if function name is surrounded by parens + ("\\(\\w+\\)\\s *(" 1 font-lock-function-name-face) + ;; Type names + ("\\<type\\>\\s *\\(\\w+\\)" 1 font-lock-type-face) + (,(concat "\\<type\\>\\s *\\w+\\s *" type-name) 1 font-lock-type-face) + ;; Arrays/slices/map value type + ;; XXX Wrong. Marks 0 in expression "foo[0] * x" + ;; (,(concat "]" type-name) 1 font-lock-type-face) + ;; Map key type + (,(concat "\\<map\\s *\\[" type-name) 1 font-lock-type-face) + ;; Channel value type + (,(concat "\\<chan\\>\\s *\\(?:<-\\)?" type-name) 1 font-lock-type-face) + ;; new/make type + (,(concat "\\<\\(?:new\\|make\\)\\>\\(?:\\s \\|)\\)*(" type-name) 1 font-lock-type-face) + ;; Type conversion + (,(concat "\\.\\s *(" type-name) 1 font-lock-type-face) + ;; Method receiver type + (,(concat "\\<func\\>\\s *(\\w+\\s +" type-name) 1 font-lock-type-face) + ;; Labels + ;; XXX Not quite right. Also marks compound literal fields. + ("^\\s *\\(\\w+\\)\\s *:\\(\\S.\\|$\\)" 1 font-lock-constant-face) + ("\\<\\(goto\\|break\\|continue\\)\\>\\s *\\(\\w+\\)" 2 font-lock-constant-face))) + "Basic font lock keywords for Go mode. Highlights keywords, +built-ins, functions, and some types.") + +;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; +;; Key map +;; + +(defvar go-mode-map + (let ((m (make-sparse-keymap))) + (define-key m "}" #'go-mode-insert-and-indent) + (define-key m ")" #'go-mode-insert-and-indent) + (define-key m "," #'go-mode-insert-and-indent) + (define-key m ":" #'go-mode-delayed-electric) + ;; In case we get : indentation wrong, correct ourselves + (define-key m "=" #'go-mode-insert-and-indent) + m) + "Keymap used by Go mode to implement electric keys.") + +(defun go-mode-insert-and-indent (key) + "Invoke the global binding of KEY, then reindent the line." + + (interactive (list (this-command-keys))) + (call-interactively (lookup-key (current-global-map) key)) + (indent-according-to-mode)) + +(defvar go-mode-delayed-point nil + "The point following the previous insertion if the insertion +was a delayed electric key. Used to communicate between +`go-mode-delayed-electric' and `go-mode-delayed-electric-hook'.") +(make-variable-buffer-local 'go-mode-delayed-point) + +(defun go-mode-delayed-electric (p) + "Perform electric insertion, but delayed by one event. + +This inserts P into the buffer, as usual, then waits for another key. +If that second key causes a buffer modification starting at the +point after the insertion of P, reindents the line containing P." + + (interactive "p") + (self-insert-command p) + (setq go-mode-delayed-point (point))) + +(defun go-mode-delayed-electric-hook (b e l) + "An after-change-function that implements `go-mode-delayed-electric'." + + (when (and go-mode-delayed-point + (= go-mode-delayed-point b)) + (save-excursion + (save-match-data + (goto-char go-mode-delayed-point) + (indent-according-to-mode)))) + (setq go-mode-delayed-point nil)) + +;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; +;; Parser +;; + +(defvar go-mode-mark-cs-end 1 + "The point at which the comment/string cache ends. The buffer +will be marked from the beginning up to this point (that is, up +to and including character (1- go-mode-mark-cs-end)).") +(make-variable-buffer-local 'go-mode-mark-cs-end) + +(defvar go-mode-mark-string-end 1 + "The point at which the string cache ends. The buffer +will be marked from the beginning up to this point (that is, up +to and including character (1- go-mode-mark-string-end)).") +(make-variable-buffer-local 'go-mode-mark-string-end) + +(defvar go-mode-mark-comment-end 1 + "The point at which the comment cache ends. The buffer +will be marked from the beginning up to this point (that is, up +to and including character (1- go-mode-mark-comment-end)).") +(make-variable-buffer-local 'go-mode-mark-comment-end) + +(defvar go-mode-mark-nesting-end 1 + "The point at which the nesting cache ends. The buffer will be +marked from the beginning up to this point.") +(make-variable-buffer-local 'go-mode-mark-nesting-end) + +(defun go-mode-mark-clear-cache (b e) + "A before-change-function that clears the comment/string and +nesting caches from the modified point on." + + (save-restriction + (widen) + (when (<= b go-mode-mark-cs-end) + ;; Remove the property adjacent to the change position. + ;; It may contain positions pointing beyond the new end mark. + (let ((b (let ((cs (get-text-property (max 1 (1- b)) 'go-mode-cs))) + (if cs (car cs) b)))) + (remove-text-properties + b (min go-mode-mark-cs-end (point-max)) '(go-mode-cs nil)) + (setq go-mode-mark-cs-end b))) + + (when (<= b go-mode-mark-string-end) + ;; Remove the property adjacent to the change position. + ;; It may contain positions pointing beyond the new end mark. + (let ((b (let ((cs (get-text-property (max 1 (1- b)) 'go-mode-string))) + (if cs (car cs) b)))) + (remove-text-properties + b (min go-mode-mark-string-end (point-max)) '(go-mode-string nil)) + (setq go-mode-mark-string-end b))) + (when (<= b go-mode-mark-comment-end) + ;; Remove the property adjacent to the change position. + ;; It may contain positions pointing beyond the new end mark. + (let ((b (let ((cs (get-text-property (max 1 (1- b)) 'go-mode-comment))) + (if cs (car cs) b)))) + (remove-text-properties + b (min go-mode-mark-string-end (point-max)) '(go-mode-comment nil)) + (setq go-mode-mark-comment-end b))) + + (when (< b go-mode-mark-nesting-end) + (remove-text-properties b (min go-mode-mark-nesting-end (point-max)) '(go-mode-nesting nil)) + (setq go-mode-mark-nesting-end b)))) + +(defmacro go-mode-parser (&rest body) + "Evaluate BODY in an environment set up for parsers that use +text properties to mark text. This inhibits changes to the undo +list or the buffer's modification status and inhibits calls to +the modification hooks. It also saves the excursion and +restriction and widens the buffer, since most parsers are +context-sensitive." + + (let ((modified-var (make-symbol "modified"))) + `(let ((buffer-undo-list t) + (,modified-var (buffer-modified-p)) + (inhibit-modification-hooks t) + (inhibit-read-only t)) + (save-excursion + (save-restriction + (widen) + (unwind-protect + (progn ,＠body) + (set-buffer-modified-p ,modified-var))))))) + +(defun go-mode-cs (&optional pos) + "Return the comment/string state at point POS. If point is +inside a comment or string (including the delimiters), this +returns a pair (START . END) indicating the extents of the +comment or string." + + (unless pos + (setq pos (point))) + (when (> pos go-mode-mark-cs-end) + (go-mode-mark-cs pos)) + (get-text-property pos 'go-mode-cs)) + +(defun go-mode-mark-cs (end) + "Mark comments and strings up to point END. Don't call this +directly; use `go-mode-cs'." + (setq end (min end (point-max))) + (go-mode-parser + (save-match-data + (let ((pos + ;; Back up to the last known state. + (let ((last-cs + (and (> go-mode-mark-cs-end 1) + (get-text-property (1- go-mode-mark-cs-end) + 'go-mode-cs)))) + (if last-cs + (car last-cs) + (max 1 (1- go-mode-mark-cs-end)))))) + (while (< pos end) + (goto-char pos) + (let ((cs-end ; end of the text property + (cond + ((looking-at "//") + (end-of-line) + (1+ (point))) + ((looking-at "/\\*") + (goto-char (+ pos 2)) + (if (search-forward "*/" (1+ end) t) + (point) + end)) + ((looking-at "\"") + (goto-char (1+ pos)) + (if (looking-at "[^\"\n\\\\]*\\(\\\\.[^\"\n\\\\]*\\)*\"") + (match-end 0) + (end-of-line) + (point))) + ((looking-at "'") + (goto-char (1+ pos)) + (if (looking-at "[^'\n\\\\]*\\(\\\\.[^'\n\\\\]*\\)*'") + (match-end 0) + (end-of-line) + (point))) + ((looking-at "`") + (goto-char (1+ pos)) + (while (if (search-forward "`" end t) + (if (eq (char-after) ?`) + (goto-char (1+ (point)))) + (goto-char end) + nil)) + (point))))) + (cond + (cs-end + (put-text-property pos cs-end 'go-mode-cs (cons pos cs-end)) + (setq pos cs-end)) + ((re-search-forward "[\"'`]\\|/[/*]" end t) + (setq pos (match-beginning 0))) + (t + (setq pos end))))) + (setq go-mode-mark-cs-end pos))))) + +(defun go-mode-in-comment (&optional pos) + "Return the comment/string state at point POS. If point is +inside a comment (including the delimiters), this +returns a pair (START . END) indicating the extents of the +comment or string." + + (unless pos + (setq pos (point))) + (when (> pos go-mode-mark-comment-end) + (go-mode-mark-comment pos)) + (get-text-property pos 'go-mode-comment)) + +(defun go-mode-mark-comment (end) + "Mark comments up to point END. Don't call this directly; use `go-mode-in-comment'." + (setq end (min end (point-max))) + (go-mode-parser + (save-match-data + (let ((pos + ;; Back up to the last known state. + (let ((last-comment + (and (> go-mode-mark-comment-end 1) + (get-text-property (1- go-mode-mark-comment-end) + 'go-mode-comment)))) + (if last-comment + (car last-comment) + (max 1 (1- go-mode-mark-comment-end)))))) + (while (< pos end) + (goto-char pos) + (let ((comment-end ; end of the text property + (cond + ((looking-at "//") + (end-of-line) + (1+ (point))) + ((looking-at "/\\*") + (goto-char (+ pos 2)) + (if (search-forward "*/" (1+ end) t) + (point) + end))))) + (cond + (comment-end + (put-text-property pos comment-end 'go-mode-comment (cons pos comment-end)) + (setq pos comment-end)) + ((re-search-forward "/[/*]" end t) + (setq pos (match-beginning 0))) + (t + (setq pos end))))) + (setq go-mode-mark-comment-end pos))))) + +(defun go-mode-in-string (&optional pos) + "Return the string state at point POS. If point is +inside a string (including the delimiters), this +returns a pair (START . END) indicating the extents of the +comment or string." + + (unless pos + (setq pos (point))) + (when (> pos go-mode-mark-string-end) + (go-mode-mark-string pos)) + (get-text-property pos 'go-mode-string)) + +(defun go-mode-mark-string (end) + "Mark strings up to point END. Don't call this +directly; use `go-mode-in-string'." + (setq end (min end (point-max))) + (go-mode-parser + (save-match-data + (let ((pos + ;; Back up to the last known state. + (let ((last-cs + (and (> go-mode-mark-string-end 1) + (get-text-property (1- go-mode-mark-string-end) + 'go-mode-string)))) + (if last-cs + (car last-cs) + (max 1 (1- go-mode-mark-string-end)))))) + (while (< pos end) + (goto-char pos) + (let ((cs-end ; end of the text property + (cond + ((looking-at "\"") + (goto-char (1+ pos)) + (if (looking-at "[^\"\n\\\\]*\\(\\\\.[^\"\n\\\\]*\\)*\"") + (match-end 0) + (end-of-line) + (point))) + ((looking-at "'") + (goto-char (1+ pos)) + (if (looking-at "[^'\n\\\\]*\\(\\\\.[^'\n\\\\]*\\)*'") + (match-end 0) + (end-of-line) + (point))) + ((looking-at "`") + (goto-char (1+ pos)) + (while (if (search-forward "`" end t) + (if (eq (char-after) ?`) + (goto-char (1+ (point)))) + (goto-char end) + nil)) + (point))))) + (cond + (cs-end + (put-text-property pos cs-end 'go-mode-string (cons pos cs-end)) + (setq pos cs-end)) + ((re-search-forward "[\"'`]" end t) + (setq pos (match-beginning 0))) + (t + (setq pos end))))) + (setq go-mode-mark-string-end pos))))) + +(defun go-mode-font-lock-cs (limit comment) + "Helper function for highlighting comment/strings. If COMMENT is t, +set match data to the next comment after point, and advance point +after it. If COMMENT is nil, use the next string. Returns nil +if no further tokens of the type exist." + ;; Ensures that `next-single-property-change' below will work properly. + (go-mode-cs limit) + (let (cs next (result 'scan)) + (while (eq result 'scan) + (if (or (>= (point) limit) (eobp)) + (setq result nil) + (setq cs (go-mode-cs)) + (if cs + (if (eq (= (char-after (car cs)) ?/) comment) + ;; If inside the expected comment/string, highlight it. + (progn + ;; If the match includes a "\n", we have a + ;; multi-line construct. Mark it as such. + (goto-char (car cs)) + (when (search-forward "\n" (cdr cs) t) + (put-text-property + (car cs) (cdr cs) 'font-lock-multline t)) + (set-match-data (list (car cs) (copy-marker (cdr cs)))) + (goto-char (cdr cs)) + (setq result t)) + ;; Wrong type. Look for next comment/string after this one. + (goto-char (cdr cs))) + ;; Not inside comment/string. Search for next comment/string. + (setq next (next-single-property-change + (point) 'go-mode-cs nil limit)) + (if (and next (< next limit)) + (goto-char next) + (setq result nil))))) + result)) + +(defun go-mode-font-lock-cs-string (limit) + "Font-lock iterator for strings." + (go-mode-font-lock-cs limit nil)) + +(defun go-mode-font-lock-cs-comment (limit) + "Font-lock iterator for comments." + (go-mode-font-lock-cs limit t)) + +(defsubst go-mode-nesting (&optional pos) + "Return the nesting at point POS. The nesting is a list +of (START . END) pairs for all braces, parens, and brackets +surrounding POS, starting at the inner-most nesting. START is +the location of the open character. END is the location of the +close character or nil if the nesting scanner has not yet +encountered the close character." + + (unless pos + (setq pos (point))) + (if (= pos 1) + '() + (when (> pos go-mode-mark-nesting-end) + (go-mode-mark-nesting pos)) + (get-text-property (- pos 1) 'go-mode-nesting))) + +(defun go-mode-mark-nesting (pos) + "Mark nesting up to point END. Don't call this directly; use +`go-mode-nesting'." + + (go-mode-cs pos) + (go-mode-parser + ;; Mark depth + (goto-char go-mode-mark-nesting-end) + (let ((nesting (go-mode-nesting)) + (last (point))) + (while (< last pos) + ;; Find the next depth-changing character + (skip-chars-forward "^(){}[]" pos) + ;; Mark everything up to this character with the current + ;; nesting + (put-text-property last (point) 'go-mode-nesting nesting) + (when nil + (let ((depth (length nesting))) + (put-text-property last (point) 'face + `((:background + ,(format "gray%d" (* depth 10))))))) + (setq last (point)) + ;; Update nesting + (unless (eobp) + (let ((ch (unless (go-mode-cs) (char-after)))) + (forward-char 1) + (case ch + ((?\( ?\{ ?\[) + (setq nesting (cons (cons (- (point) 1) nil) + nesting))) + ((?\) ?\} ?\]) + (when nesting + (setcdr (car nesting) (- (point) 1)) + (setq nesting (cdr nesting)))))))) + ;; Update state + (setq go-mode-mark-nesting-end last)))) + +;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; +;; Indentation +;; + +(defvar go-mode-non-terminating-keywords-regexp + (let* ((kws go-mode-keywords) + (kws (remove "break" kws)) + (kws (remove "continue" kws)) + (kws (remove "fallthrough" kws)) + (kws (remove "return" kws))) + (regexp-opt kws 'words)) + "Regular expression matching all Go keywords that *do not* +implicitly terminate a statement.") + +(defun go-mode-semicolon-p () + "True iff point immediately follows either an explicit or +implicit semicolon. Point should immediately follow the last +token on the line." + + ;; #Semicolons + (case (char-before) + ((?\;) t) + ;; String literal + ((?' ?\" ?`) t) + ;; One of the operators and delimiters ++, --, ), ], or } + ((?+) (eq (char-before (1- (point))) ?+)) + ((?-) (eq (char-before (1- (point))) ?-)) + ((?\) ?\] ?\}) t) + ;; An identifier or one of the keywords break, continue, + ;; fallthrough, or return or a numeric literal + (otherwise + (save-excursion + (when (/= (skip-chars-backward "[:word:]_") 0) + (not (looking-at go-mode-non-terminating-keywords-regexp))))))) + +(defun go-mode-whitespace-p (char) + "Is newline, or char whitespace in the syntax table for go." + (or (eq char ?\n) + (= (char-syntax char) ?\ ))) + +(defun go-mode-backward-skip-comments () + "Skip backward over comments and whitespace." + ;; only proceed if point is in a comment or white space + (if (or (go-mode-in-comment) + (go-mode-whitespace-p (char-after (point)))) + (let ((loop-guard t)) + (while (and + loop-guard + (not (bobp))) + + (cond ((go-mode-whitespace-p (char-after (point))) + ;; moves point back over any whitespace + (re-search-backward "[^[:space:]]")) + + ((go-mode-in-comment) + ;; move point to char preceeding current comment + (goto-char (1- (car (go-mode-in-comment))))) + + ;; not in a comment or whitespace? we must be done. + (t (setq loop-guard nil) + (forward-char 1))))))) + +(defun go-mode-indentation () + "Compute the ideal indentation level of the current line. + +To the first order, this is the brace depth of the current line, +plus parens that follow certain keywords. case, default, and +labels are outdented one level, and continuation lines are +indented one level." + + (save-excursion + (back-to-indentation) + (let ((cs (go-mode-cs))) + ;; Treat comments and strings differently only if the beginning + ;; of the line is contained within them + (when (and cs (= (point) (car cs))) + (setq cs nil)) + ;; What type of context am I in? + (cond + ((and cs (save-excursion + (goto-char (car cs)) + (looking-at "\\s\""))) + ;; Inside a multi-line string. Don't mess with indentation. + nil) + (cs + ;; Inside a general comment + (goto-char (car cs)) + (forward-char 1) + (current-column)) + (t + ;; Not in a multi-line string or comment + (let ((indent 0) + (inside-indenting-paren nil)) + ;; Count every enclosing brace, plus parens that follow + ;; import, const, var, or type and indent according to + ;; depth. This simple rule does quite well, but also has a + ;; very large extent. It would be better if we could mimic + ;; some nearby indentation. + (save-excursion + (skip-chars-forward "})") + (let ((first t)) + (dolist (nest (go-mode-nesting)) + (case (char-after (car nest)) + ((?\{) + (incf indent tab-width)) + ((?\() + (goto-char (car nest)) + (go-mode-backward-skip-comments) + (backward-char) + ;; Really just want the token before + (when (looking-back "\\<import\\|const\\|var\\|type\\|package" + (max (- (point) 7) (point-min))) + (incf indent tab-width) + (when first + (setq inside-indenting-paren t))))) + (setq first nil)))) + + ;; case, default, and labels are outdented 1 level + (when (looking-at "\\<case\\>\\|\\<default\\>\\|\\w+\\s *:\\(\\S.\\|$\\)") + (decf indent tab-width)) + + (when (looking-at "\\w+\\s *:.+,\\s *$") + (incf indent tab-width)) + + ;; Continuation lines are indented 1 level + (beginning-of-line) ; back up to end of previous line + (backward-char) + (go-mode-backward-skip-comments) ; back up past any comments + (when (case (char-before) + ((nil ?\{ ?:) + ;; At the beginning of a block or the statement + ;; following a label. + nil) + ((?\() + ;; Usually a continuation line in an expression, + ;; unless this paren is part of a factored + ;; declaration. + (not inside-indenting-paren)) + ((?,) + ;; Could be inside a literal. We're a little + ;; conservative here and consider any comma within + ;; curly braces (as opposed to parens) to be a + ;; literal separator. This will fail to recognize + ;; line-breaks in parallel assignments as + ;; continuation lines. + (let ((depth (go-mode-nesting))) + (and depth + (not (eq (char-after (caar depth)) ?\{))))) + (t + ;; We're in the middle of a block. Did the + ;; previous line end with an implicit or explicit + ;; semicolon? + (not (go-mode-semicolon-p)))) + (incf indent tab-width)) + + (max indent 0))))))) + +(defun go-mode-indent-line () + "Indent the current line according to `go-mode-indentation'." + (interactive) + + ;; turn off case folding to distinguish keywords from identifiers + ;; e.g. "default" is a keyword; "Default" can be a variable name. + (let ((case-fold-search nil)) + (let ((col (go-mode-indentation))) + (when col + (let ((offset (- (current-column) (current-indentation)))) + (indent-line-to col) + (when (> offset 0) + (forward-char offset))))))) + +;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; +;; Go mode +;; + +;;;###autoload +(define-derived-mode go-mode nil "Go" + "Major mode for editing Go source text. + +This provides basic syntax highlighting for keywords, built-ins, +functions, and some types. It also provides indentation that is +\(almost) identical to gofmt." + + ;; Font lock + (set (make-local-variable 'font-lock-defaults) + '(go-mode-font-lock-keywords nil nil nil nil)) + + ;; Remove stale text properties + (save-restriction + (widen) + (remove-text-properties 1 (point-max) + '(go-mode-cs nil go-mode-nesting nil))) + + ;; Reset the syntax mark caches + (setq go-mode-mark-cs-end 1 + go-mode-mark-nesting-end 1) + (add-hook 'before-change-functions #'go-mode-mark-clear-cache nil t) + + ;; Indentation + (set (make-local-variable 'indent-line-function) + #'go-mode-indent-line) + (add-hook 'after-change-functions #'go-mode-delayed-electric-hook nil t) + + ;; Comments + (set (make-local-variable 'comment-start) "// ") + (set (make-local-variable 'comment-end) "") + + ;; Go style + (setq indent-tabs-mode t)) + +;;;###autoload +(add-to-list 'auto-mode-alist (cons "\\.go$" #'go-mode)) + +(defun go-mode-reload () + "Reload go-mode.el and put the current buffer into Go mode. +Useful for development work." + + (interactive) + (unload-feature 'go-mode) + (require 'go-mode) + (go-mode)) + +;;;###autoload +(defun gofmt () + "Pipe the current buffer through the external tool `gofmt`. +Replace the current buffer on success; display errors on failure." + + (interactive) + (let ((currconf (current-window-configuration))) + (let ((srcbuf (current-buffer))) + (with-temp-buffer + (let ((outbuf (current-buffer)) + (errbuf (get-buffer-create "*Gofmt Errors*")) + (coding-system-for-read 'utf-8) ;; use utf-8 with subprocesses + (coding-system-for-write 'utf-8)) + (with-current-buffer errbuf (erase-buffer)) + (with-current-buffer srcbuf + (save-restriction + (let (deactivate-mark) + (widen) + (if (= 0 (shell-command-on-region (point-min) (point-max) "gofmt" + outbuf nil errbuf)) + ;; restore window config + ;; gofmt succeeded: replace the current buffer with outbuf, + ;; restore the mark and point, and discard errbuf. + (let ((old-mark (mark t)) + (old-point (point)) + (old-start (window-start))) + (erase-buffer) + (insert-buffer-substring outbuf) + (set-window-configuration currconf) + (set-window-start (selected-window) (min old-start (point-max))) + (goto-char (min old-point (point-max))) + (if old-mark (push-mark (min old-mark (point-max)) t)) + (kill-buffer errbuf)) + + ;; gofmt failed: display the errors + (display-buffer errbuf))))) + + ;; Collapse any window opened on outbuf if shell-command-on-region + ;; displayed it. + (delete-windows-on outbuf)))))) + +;;;###autoload +(defun gofmt-before-save () + "Add this to .emacs to run gofmt on the current buffer when saving: + (add-hook 'before-save-hook #'gofmt-before-save)" + + (interactive) + (when (eq major-mode 'go-mode) (gofmt))) + +(defun godoc-read-query () + "Read a godoc query from the minibuffer." + ;; Compute the default query as the symbol under the cursor. + ;; TODO: This does the wrong thing for e.g. multipart.NewReader (it only grabs + ;; half) but I see no way to disambiguate that from e.g. foobar.SomeMethod. + (let* ((bounds (bounds-of-thing-at-point 'symbol)) + (symbol (if bounds + (buffer-substring-no-properties (car bounds) + (cdr bounds))))) + (read-string (if symbol + (format "godoc (default %s): " symbol) + "godoc: ") + nil nil symbol))) + +(defun godoc-get-buffer (query) + "Get an empty buffer for a godoc query." + (let* ((buffer-name (concat "*godoc " query "*")) + (buffer (get-buffer buffer-name))) + ;; Kill the existing buffer if it already exists. + (when buffer (kill-buffer buffer)) + (get-buffer-create buffer-name))) + +(defun godoc-buffer-sentinel (proc event) + "Sentinel function run when godoc command completes." + (with-current-buffer (process-buffer proc) + (cond ((string= event "finished\n") ;; Successful exit. + (goto-char (point-min)) + (display-buffer (current-buffer) 'not-this-window)) + ((not (= (process-exit-status proc) 0)) ;; Error exit. + (let ((output (buffer-string))) + (kill-buffer (current-buffer)) + (message (concat "godoc: " output))))))) + +;;;###autoload +(defun godoc (query) + "Show go documentation for a query, much like M-x man." + (interactive (list (godoc-read-query))) + (unless (string= query "") + (set-process-sentinel + (start-process-shell-command "godoc" (godoc-get-buffer query) + (concat "godoc " query)) + 'godoc-buffer-sentinel) + nil)) + +(provide 'go-mode) diff -r 9a5e5e733261 -r a246dff1f055 prog-modes.texi --- a/prog-modes.texi Fri Dec 23 11:41:10 2011 -0500 +++ b/prog-modes.texi Sun May 13 21:33:45 2012 +0200 ＠＠ -3,6 +3,7 ＠＠ ＠c Copyright (C) 2002, 2003 Free Software Foundation, Inc. ＠c Copyright (C) 2003 Jake Colman <jake.colman(a)xemacs.org&gt; ＠c Copyright (C) 2004 Ville Skytt~ <scop(a)xemacs.org&gt; +＠c Copyright (C) 2012 Mats Lidell <matsl(a)xemacs.org&gt; ＠c ＠c ＠setfilename prog-modes.info ＠settitle Programming Modes for XEmacs ＠＠ -67,6 +68,7 ＠＠ * cvs:: Light CVS Support * diff-mode:: Viewing and Editing Context Diffs * eiffel:: Editing Eiffel Code +* go-mode:: Editing Go Code * icon:: Editing Icon Code * javascript-mode:: Editing JavaScript Code * ksh-mode:: Editing Shell Script (sh, ksh, bash) Code ＠＠ -388,7 +390,7 ＠＠ M-x customize-group RET diff-mode RET ＠end example -＠node eiffel, icon, diff-mode, Top +＠node eiffel, go-mode, diff-mode, Top ＠chapter Editing Eiffel Code This mode is used for editing Eiffel code. It is automatically invoked for ＠＠ -433,7 +435,61 ＠＠ ＠uref{http://www.engin.umd.umich.edu/CIS/course.des/cis400/eiffel/eiffel.html,the Eiffel Web Site}. -＠node icon, javascript-mode, eiffel, Top +＠node go-mode, icon, eiffel, Top + +＠chapter Editing Go Code + +This mode is used for editing Go code. It is automatically invoked for +buffers visiting any file ending in an extension of ＠file{.go}. + +Turning on Go mode runs the hook ＠code{go-mode-hook} at the end of +initialization. + +The mode provides the following features: + +＠itemize ＠bullet +＠item Basic syntax highlighting for keywords, built-ins, functions and +some types +＠item Tab indents for Go code. Identation is almost identical to gofmt +＠end itemize + +The following key mappings are defined: + +＠multitable {M-backspace } {backward-delete-char-untabify} +＠item ＠code{)} ＠tab go-mode-insert-and-indent +＠item ＠code{,} ＠tab go-mode-insert-and-indent +＠item ＠code{:} ＠tab go-mode-delayed-electric +＠item ＠code{=} ＠tab go-mode-insert-and-indent +＠item ＠code{＠}} ＠tab go-mode-insert-and-indent +＠end multitable + +Other useful functions are: + +＠table ＠code +＠item gofmt +Uses the gofmt tool to format the current buffer. The current buffer +is replaced on success. On failure an error message is displayed. + +＠item godoc +Show Go documentation for a query in a style similar to M-x man. + +＠end table + +＠menu +* About Go: about-go. +＠end menu + +＠node about-go, , go-mode, go-mode +＠section About Go + +Go is a high-level, general-purpose programming language that is +compiled, uses garbage collection and has strong support for +concurrent programming. It is open source and developed by Google Inc. + +For more information on Go see +＠uref{http://www.golang.org,The Go Programming Language}. + +＠node icon, javascript-mode, go-mode, Top ＠chapter Editing Icon Code This mode is used for editing Icon code. It is automatically invoked for Yours -- %% Mats _______________________________________________ XEmacs-Patches mailing list XEmacs-Patches(a)xemacs.org http://lists.xemacs.org/mailman/listinfo/xemacs-patches