emacs/code/elpa/lsp-mode-20240319.1043/lsp-clangd.el

319 lines
13 KiB
EmacsLisp

;;; lsp-clangd.el --- LSP clients for the C Languages Family -*- lexical-binding: t; -*-
;; Copyright (C) 2020 Daniel Martin & emacs-lsp maintainers
;; URL: https://github.com/emacs-lsp/lsp-mode
;; Keywords: languages, c, cpp, clang
;; This program 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.
;; This program 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 this program. If not, see <http://www.gnu.org/licenses/>.
;;; Commentary:
;; LSP clients for the C Languages Family.
;; ** Clang-tidy Flycheck integration (Clangd) **
;;
;; If you invoke `flycheck-display-error-explanation' on a
;; `clang-tidy' error (if Clangd is configured to show `clang-tidy'
;; diagnostics), Emacs will open a detailed explanation about the
;; message by querying the LLVM website. As an embedded web browser is
;; used to show the documentation, this feature requires that Emacs is
;; compiled with libxml2 support.
;;; Code:
(require 'lsp-mode)
(require 'cl-lib)
(require 'rx)
(require 'seq)
(require 'dom)
(eval-when-compile (require 'subr-x))
(require 'dash)
(require 's)
(defvar flycheck-explain-error-buffer)
(declare-function flycheck-error-id "ext:flycheck" (err) t)
(declare-function flycheck-error-group "ext:flycheck" (err) t)
(declare-function flycheck-error-message "ext:flycheck" (err) t)
(defcustom lsp-clangd-version "15.0.6"
"Clangd version to download.
It has to be set before `lsp-clangd.el' is loaded and it has to
be available here: https://github.com/clangd/clangd/releases/"
:type 'string
:group 'lsp-clangd
:package-version '(lsp-mode . "8.0.0"))
(defcustom lsp-clangd-download-url
(format (pcase system-type
('darwin "https://github.com/clangd/clangd/releases/download/%s/clangd-mac-%s.zip")
('windows-nt "https://github.com/clangd/clangd/releases/download/%s/clangd-windows-%s.zip")
(_ "https://github.com/clangd/clangd/releases/download/%s/clangd-linux-%s.zip"))
lsp-clangd-version
lsp-clangd-version)
"Automatic download url for clangd"
:type 'string
:group 'lsp-clangd
:package-version '(lsp-mode . "8.0.0"))
(defcustom lsp-clangd-binary-path
(f-join lsp-server-install-dir (format "clangd/clangd_%s/bin"
lsp-clangd-version)
(pcase system-type
('windows-nt "clangd.exe")
(_ "clangd")))
"The path to `clangd' binary."
:type 'file
:group 'lsp-clangd
:package-version '(lsp-mode . "8.0.0"))
(lsp-dependency
'clangd
`(:download :url lsp-clangd-download-url
:decompress :zip
:store-path ,(f-join lsp-server-install-dir "clangd" "clangd.zip")
:binary-path lsp-clangd-binary-path
:set-executable? t))
(defun lsp-cpp-flycheck-clang-tidy--skip-http-headers ()
"Position point just after HTTP headers."
(re-search-forward "^$"))
(defun lsp-cpp-flycheck-clang-tidy--narrow-to-http-body ()
"Narrow the current buffer to contain the body of an HTTP response."
(lsp-cpp-flycheck-clang-tidy--skip-http-headers)
(narrow-to-region (point) (point-max)))
(defun lsp-cpp-flycheck-clang-tidy--decode-region-as-utf8 (start end)
"Decode a region from START to END in UTF-8."
(condition-case nil
(decode-coding-region start end 'utf-8)
(coding-system-error nil)))
(defun lsp-cpp-flycheck-clang-tidy--remove-crlf ()
"Remove carriage return and line feeds from the current buffer."
(save-excursion
(while (re-search-forward "\r$" nil t)
(replace-match "" t t))))
(defun lsp-cpp-flycheck-clang-tidy--extract-relevant-doc-section ()
"Extract the parts of the LLVM clang-tidy documentation that are relevant.
This function assumes that the current buffer contains the result
of browsing `clang.llvm.org', as returned by `url-retrieve'.
More concretely, this function returns the main <div> element
with class `section', and also removes `headerlinks'."
(goto-char (point-min))
(lsp-cpp-flycheck-clang-tidy--narrow-to-http-body)
(lsp-cpp-flycheck-clang-tidy--decode-region-as-utf8 (point-min) (point-max))
(lsp-cpp-flycheck-clang-tidy--remove-crlf)
(let* ((dom (libxml-parse-html-region (point-min) (point-max)))
(section (dom-by-class dom "section")))
(dolist (headerlink (dom-by-class section "headerlink"))
(dom-remove-node section headerlink))
section))
(defun lsp-cpp-flycheck-clang-tidy--explain-error (explanation &rest args)
"Explain an error in the Flycheck error explanation buffer using EXPLANATION.
EXPLANATION is a function with optional ARGS that, when
evaluated, inserts the content in the appropriate Flycheck
buffer."
(with-current-buffer flycheck-explain-error-buffer
(let ((inhibit-read-only t)
(inhibit-modification-hooks t))
(erase-buffer)
(apply explanation args)
(goto-char (point-min)))))
(defun lsp-cpp-flycheck-clang-tidy--show-loading-status ()
"Show a loading string while clang-tidy documentation is fetched from llvm.org.
Recent versions of `flycheck' call `display-message-or-buffer' to
display error explanations. `display-message-or-buffer' displays
the documentation string either in the echo area or in a separate
window, depending on the string's height. This function forces to
always display it in a separate window by appending the required
number of newlines."
(let* ((num-lines-threshold
(round (if resize-mini-windows
(cond ((floatp max-mini-window-height)
(* (frame-height)
max-mini-window-height))
((integerp max-mini-window-height)
max-mini-window-height)
(t
1))
1)))
(extra-new-lines (make-string (1+ num-lines-threshold) ?\n)))
(concat "Loading documentation..." extra-new-lines)))
(defun lsp-cpp-flycheck-clang-tidy--show-documentation (error-id)
"Show clang-tidy documentation about ERROR-ID.
Information comes from the clang.llvm.org website."
;; Example error-id: modernize-loop-convert
;; Example url: https://clang.llvm.org/extra/clang-tidy/checks/modernize/loop-convert.html
(setq error-id (s-join "/" (s-split-up-to "-" error-id 1 t)))
(url-retrieve (format
"https://clang.llvm.org/extra/clang-tidy/checks/%s.html" error-id)
(lambda (status)
(if-let ((error-status (plist-get status :error)))
(lsp-cpp-flycheck-clang-tidy--explain-error
#'insert
(format
"Error accessing clang-tidy documentation: %s"
(error-message-string error-status)))
(let ((doc-contents
(lsp-cpp-flycheck-clang-tidy--extract-relevant-doc-section)))
(lsp-cpp-flycheck-clang-tidy--explain-error
#'shr-insert-document doc-contents)))))
(lsp-cpp-flycheck-clang-tidy--show-loading-status))
;;;###autoload
(defun lsp-cpp-flycheck-clang-tidy-error-explainer (error)
"Explain a clang-tidy ERROR by scraping documentation from llvm.org."
(unless (fboundp 'libxml-parse-html-region)
(error "This function requires Emacs to be compiled with libxml2"))
(if-let ((clang-tidy-error-id (flycheck-error-id error)))
(condition-case err
(lsp-cpp-flycheck-clang-tidy--show-documentation clang-tidy-error-id)
(error
(format
"Error accessing clang-tidy documentation: %s"
(error-message-string err))))
(error "The clang-tidy error message does not contain an [error-id]")))
;;; lsp-clangd
(defgroup lsp-clangd nil
"LSP support for C-family languages (C, C++, Objective-C, Objective-C++, CUDA), using clangd."
:group 'lsp-mode
:link '(url-link "https://clang.llvm.org/extra/clangd"))
(defcustom lsp-clients-clangd-executable nil
"The clangd executable to use.
When `'non-nil' use the name of the clangd executable file
available in your path to use. Otherwise the system will try to
find a suitable one. Set this variable before loading lsp."
:group 'lsp-clangd
:risky t
:type '(choice (file :tag "Path")
(const :tag "Auto" nil)))
(defvar lsp-clients--clangd-default-executable nil
"Clang default executable full path when found.
This must be set only once after loading the clang client.")
(defcustom lsp-clients-clangd-args '("--header-insertion-decorators=0")
"Extra arguments for the clangd executable."
:group 'lsp-clangd
:risky t
:type '(repeat string))
(defcustom lsp-clients-clangd-library-directories '("/usr")
"List of directories which will be considered to be libraries."
:risky t
:type '(repeat string)
:group 'lsp-clangd
:package-version '(lsp-mode . "8.0.1"))
(defun lsp-clients--clangd-command ()
"Generate the language server startup command."
(unless lsp-clients--clangd-default-executable
(setq lsp-clients--clangd-default-executable
(or (lsp-package-path 'clangd)
(-first #'executable-find
(-map (lambda (version)
(concat "clangd" version))
;; Prefer `clangd` without a version number appended.
(cl-list* "" (-map
(lambda (vernum) (format "-%d" vernum))
(number-sequence 17 6 -1)))))
(lsp-clients-executable-find "xcodebuild" "-find-executable" "clangd")
(lsp-clients-executable-find "xcrun" "--find" "clangd"))))
`(,(or lsp-clients-clangd-executable lsp-clients--clangd-default-executable "clangd")
,@lsp-clients-clangd-args))
(lsp-register-client
(make-lsp-client :new-connection (lsp-stdio-connection
'lsp-clients--clangd-command)
:activation-fn (lsp-activate-on "c" "cpp" "objective-c" "cuda")
:priority -1
:server-id 'clangd
:library-folders-fn (lambda (_workspace) lsp-clients-clangd-library-directories)
:download-server-fn (lambda (_client callback error-callback _update?)
(lsp-package-ensure 'clangd callback error-callback))))
(defun lsp-clangd-join-region (beg end)
"Apply join-line from BEG to END.
This function is useful when an indented function prototype needs
to be shown in a single line."
(save-excursion
(let ((end (copy-marker end)))
(goto-char beg)
(while (< (point) end)
(join-line 1)))
(s-trim (buffer-string))))
(cl-defmethod lsp-clients-extract-signature-on-hover (contents (_server-id (eql clangd)))
"Extract a representative line from clangd's CONTENTS, to show in the echo area.
This function tries to extract the type signature from CONTENTS,
or the first line if it cannot do so. A single line is always
returned to avoid that the echo area grows uncomfortably."
(with-temp-buffer
(-let [value (lsp:markup-content-value contents)]
(insert value)
(goto-char (point-min))
(if (re-search-forward (rx (seq "```cpp\n"
(opt (group "//"
(zero-or-more nonl)
"\n"))
(group
(one-or-more
(not (any "`")))
"\n")
"```")) nil t nil)
(progn (narrow-to-region (match-beginning 2) (match-end 2))
(lsp--render-element (lsp-make-marked-string
:language "cpp"
:value (lsp-clangd-join-region (point-min) (point-max)))))
(car (s-lines (lsp--render-element contents)))))))
(cl-defmethod lsp-diagnostics-flycheck-error-explainer (e (_server-id (eql clangd)))
"Explain a `flycheck-error' E that was generated by the Clangd language server."
(cond ((string-equal "clang-tidy" (flycheck-error-group e))
(lsp-cpp-flycheck-clang-tidy-error-explainer e))
(t (flycheck-error-message e))))
(defun lsp-clangd-find-other-file (&optional new-window)
"Switch between the corresponding C/C++ source and header file.
If NEW-WINDOW (interactively the prefix argument) is non-nil,
open in a new window.
Only works with clangd."
(interactive "P")
(let ((other (lsp-send-request (lsp-make-request
"textDocument/switchSourceHeader"
(lsp--text-document-identifier)))))
(unless (s-present? other)
(user-error "Could not find other file"))
(funcall (if new-window #'find-file-other-window #'find-file)
(lsp--uri-to-path other))))
(lsp-consistency-check lsp-clangd)
(provide 'lsp-clangd)
;;; lsp-clangd.el ends here