;;; semantic/symref/grep.el --- Symref implementation using find/grep -*- lexical-binding: t; -*-
;; Copyright (C) 2008-2024 Free Software Foundation, Inc.
;; Author: Eric M. Ludlam <zappo@gnu.org>
;; This file is part of GNU Emacs.
;; GNU Emacs is free software: you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation, either version 3 of the License, or
;; (at your option) any later version.
;; GNU Emacs is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
;; GNU General Public License for more details.
;; You should have received a copy of the GNU General Public License
;; along with GNU Emacs. If not, see <https://www.gnu.org/licenses/>.
;;; Commentary:
;;
;; Implement the symref tool API using the external tools find/grep.
;;
;; The symref GREP tool uses grep in a project to find symbol references.
;; This is a lowest-common-denominator tool with sucky performance that
;; can be used in small projects to find symbol references.
(require 'semantic/symref)
(require 'grep)
;;; Code:
;;; GREP
;;;###autoload
(defclass semantic-symref-tool-grep (semantic-symref-tool-baseclass)
(
)
"A symref tool implementation using grep.
This tool uses EDE to find the root of the project, then executes
`find-grep' in the project. The output is parsed for hits and
those hits returned.")
(defvar semantic-symref-filepattern-alist
'((c-mode "*.[ch]")
(c-ts-mode "*.[ch]")
(c++-mode "*.[chCH]" "*.[ch]pp" "*.cc" "*.hh")
(c++-ts-mode "*.[chCH]" "*.[ch]pp" "*.cc" "*.hh")
(html-mode "*.html" "*.shtml" "*.php")
(mhtml-mode "*.html" "*.shtml" "*.php") ; FIXME: remove
; duplication of
; HTML-related patterns.
; Maybe they belong in the
; major mode definition?
(ruby-mode "*.r[bu]" "*.rake" "*.gemspec" "*.erb" "*.haml"
"Rakefile" "Thorfile" "Capfile" "Guardfile" "Vagrantfile")
(ruby-ts-mode "*.r[bu]" "*.rake" "*.gemspec" "*.erb" "*.haml"
"Rakefile" "Thorfile" "Capfile" "Guardfile" "Vagrantfile")
(python-mode "*.py" "*.pyi" "*.pyw")
(python-ts-mode "*.py" "*.pyi" "*.pyw")
(perl-mode "*.pl" "*.PL")
(cperl-mode "*.pl" "*.PL")
(lisp-interaction-mode "*.el" "*.ede" ".emacs" "_emacs")
)
"List of major modes and file extension pattern.
See find -name man page for format.")
(defun semantic-symref-derive-find-filepatterns (&optional mode)
;; FIXME: This should be moved to grep.el, where it could be used
;; for "C-u M-x grep" as well.
"Derive a list of file (glob) patterns for the current buffer.
Looks first in `semantic-symref-filepattern-alist'. If it is not
there, it then looks in `auto-mode-alist', and attempts to derive something
from that.
Optional argument MODE specifies the `major-mode' to test."
;; First, try the filepattern alist.
(let* ((mode (or mode major-mode))
(pat (cdr (assoc mode semantic-symref-filepattern-alist))))
(when (not pat)
;; No hit, try auto-mode-alist.
(dolist (X auto-mode-alist)
(when (and (eq (cdr X) mode)
;; Only take in simple patterns, so try to convert this one.
(string-match "\\\\\\.\\([^\\'>]+\\)\\\\'" (car X)))
(push (concat "*." (match-string 1 (car X))) pat))))
;; Convert the list into some find-flags.
(if (null pat)
(error "Customize `semantic-symref-filepattern-alist' for %S"
major-mode)
(let ((args `("-name" ,(car pat))))
(if (null (cdr pat))
args
`("(" ,@args
,@(mapcan (lambda (s) `("-o" "-name" ,s)) (cdr pat))
")"))))))
(defvar semantic-symref-grep-flags)
(defvar semantic-symref-grep-expand-keywords
(condition-case nil
(let* ((kw (copy-alist grep-expand-keywords))
(C (assoc "<C>" kw)))
(setcdr C 'semantic-symref-grep-flags)
kw)
(error nil))
"Grep expand keywords used when expanding templates for symref.")
(defun semantic-symref-grep-use-template (rootdir filepattern flags pattern)
"Use the grep template expand feature to create a grep command.
ROOTDIR is the root location to run the `find' from.
FILEPATTERN is a string representing find flags for searching file patterns.
FLAGS are flags passed to Grep, such as -n or -l.
PATTERN is the pattern used by Grep."
;; We have grep-compute-defaults. Let's use it.
(grep-compute-defaults)
(let* ((semantic-symref-grep-flags flags)
(grep-expand-keywords semantic-symref-grep-expand-keywords)
(cmd (grep-expand-template
(if (memq system-type '(windows-nt ms-dos))
;; FIXME: Is this still needed?
;; grep-find uses '--color=always' on MS-Windows
;; because it wants the colorized output, to show
;; it to the user. By contrast, here we don't show
;; the output, and the SGR escapes get in the way
;; of parsing the output.
(replace-regexp-in-string "--color=always" ""
grep-find-template t t)
grep-find-template)
pattern
filepattern
rootdir)))
cmd))
(defcustom semantic-symref-grep-shell shell-file-name
"The shell command to use for executing find/grep.
This shell should support pipe redirect syntax."
:group 'semantic
:type 'string)
(defun semantic-symref-grep--quote-grep (string)
"Quote STRING as a grep-syntax regexp."
(replace-regexp-in-string (rx (in ".^$*[\\"))
(lambda (s) (concat "\\" s))
string nil t))
(defvar semantic-symref-grep--local-dir nil)
(cl-defmethod semantic-symref-perform-search ((tool semantic-symref-tool-grep))
"Perform a search with Grep."
;; Grep doesn't support some types of searches.
(let ((st (oref tool searchtype)))
(when (not (memq st '(symbol regexp)))
(error "Symref impl GREP does not support searchtype of %s" st))
)
;; Find the root of the project, and do a find-grep...
(let* (;; Find the file patterns to use.
(rootdir (semantic-symref-calculate-rootdir))
(filepatterns (semantic-symref-derive-find-filepatterns))
(filepattern (mapconcat #'shell-quote-argument filepatterns " "))
;; Grep based flags.
(grepflags (cond ((eq (oref tool resulttype) 'file)
"-l ")
((eq (oref tool searchtype) 'regexp)
"-nE ")
(t "-nw ")))
(searchfor (oref tool searchfor))
(greppat (if (eq (oref tool searchtype) 'regexp)
searchfor
(semantic-symref-grep--quote-grep searchfor)))
;; Misc
(b (get-buffer-create "*Semantic SymRef*"))
(ans nil)
)
(with-current-buffer b
(erase-buffer)
(setq default-directory rootdir)
(let ((cmd (semantic-symref-grep-use-template
"."
filepattern grepflags greppat)))
(process-file semantic-symref-grep-shell nil b nil
shell-command-switch cmd)))
(let ((semantic-symref-grep--local-dir (directory-file-name (file-local-name rootdir))))
(setq ans (semantic-symref-parse-tool-output tool b)))
;; Return the answer
ans))
(cl-defmethod semantic-symref-parse-tool-output-one-line ((tool semantic-symref-tool-grep))
"Parse one line of grep output, and return it as a match list.
Moves cursor to end of the match."
(pcase-let
((`(,grep-re ,file-group ,line-group . ,_) (car grep-regexp-alist)))
(cond ((eq (oref tool resulttype) 'file)
;; Search for files
(when (re-search-forward "^\\([^\n]+\\)$" nil t)
(match-string 1)))
((eq (oref tool resulttype) 'line-and-text)
(when (re-search-forward grep-re nil t)
(list (string-to-number (match-string line-group))
(concat semantic-symref-grep--local-dir (substring (match-string file-group) 1))
(buffer-substring-no-properties (point) (line-end-position)))))
(t
(when (re-search-forward grep-re nil t)
(cons (string-to-number (match-string line-group))
(concat semantic-symref-grep--local-dir (substring (match-string file-group) 1)))
)))))
(provide 'semantic/symref/grep)
;; Local variables:
;; generated-autoload-file: "../loaddefs.el"
;; generated-autoload-load-name: "semantic/symref/grep"
;; End:
;;; semantic/symref/grep.el ends here