solidity-mode.el

;;; solidity-mode.el --- Major mode for ethereum's solidity language

;; Copyright (C) 2015-2018  Lefteris Karapetsas

;; Author: Lefteris Karapetsas  <lefteris@refu.co>
;; Keywords: languages
;; Version: 0.1.8

;; 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:

;; Solidity is a high-level language whose syntax is similar to that
;; of Javascript and it is designed to compile to code for the
;; Ethereum Virtual Machine.

;; This package provides a major mode for writing Solidity code.

;;; Code:

(require 'cc-mode)
(require 'solidity-common)


;;; --- Customizable variables ---
(defgroup solidity nil
  "Major mode for ethereum's solidity language"
  :group 'languages ;; Emacs -> Programming -> Languages
  :prefix "solidity-"
  :link '(url-link :tag "Github" "https://github.com/ethereum/emacs-solidity"))

(defcustom solidity-mode-hook nil
  "Callback hook to execute whenever a solidity file is loaded."
  :group 'solidity)

(defcustom solidity-comment-style 'star
  "Denotes the style of comments to use for solidity when commenting.

This option will define what kind of comments will be input into the buffer by
commands like `comment-region'.  The default value is 'star.
Possible values are:

`star'
    Follow the same styling as C mode does by default having all comments
    obey the /* .. */ style.

`slash'
    All comments will start with //."
  :group 'solidity
  :type '(choice (const :tag "Commenting starts with /* and ends with */" star)
                 (const :tag "Commenting starts with //" slash))
  :package-version '(solidity . "0.1.7")
  :safe #'symbolp)

(defvar solidity-mode-map
  (let ((map (make-sparse-keymap)))
    (define-key map "\C-j" 'newline-and-indent)
    (define-key map (kbd "C-c C-g") 'solidity-estimate-gas-at-point)
    map)
  "Keymap for solidity major mode.")

(defvar solidity-checker t "The solidity flycheck syntax checker.")
(defvar solidity-mode t "The solidity major mode.")

;;;###autoload
(add-to-list 'auto-mode-alist '("\\.sol\\'" . solidity-mode))

(defun solidity-filter (condp lst)
  "A simple version of a list filter.  Depending on CONDP filter LST."
  (delq nil
        (mapcar (lambda (x) (and (funcall condp x) x)) lst)))

(defconst solidity-keywords
  '("after"
    "as"
    "assembly"
    "break"
    "constant"
    "anonymous"
    "continue"
    "contract"
    "default"
    "delete"
    "do"
    "else"
    "event"
    "external"
    "for"
    "function"
    "if"
    "import"
    "in"
    "is"
    "indexed"
    "library"
    "mapping"
    "modifier"
    "new"
    "pragma"
    "private"
    "public"
    "internal"
    "pure"
    "view"
    "return"
    "returns"
    "struct"
    "switch"
    "this"
    "using"
    "var"
    "while"
    "enum"
    "throw"
    "assert"
    "require"
    "revert"
    "storage"
    "memory"
    )
  "Keywords of the solidity language.")

(defconst solidity-tofontify-keywords
  (solidity-filter
   (lambda (x) (not (member x '("contract"
                                "library"))))
   solidity-keywords)
  "Keywords that will be fontified as they are and don't have special rules."
  )

(defconst solidity-constants
  '("true" "false"
    "wei"
    "szabo"
    "finney"
    "ether"
    "seconds"
    "minutes"
    "hours"
    "days"
    "weeks"
    "years"
    )
  "Constants in the solidity language.")

(defconst solidity-variable-modifier
  '("constant"
    "public"
    "indexed"
    "storage"
    "memory"
    )
  "Modifiers of variables in solidity.")

(defconst solidity-builtin-types
  '("address"
    "bool"
    "bytes"
    "bytes0"
    "bytes1"
    "bytes2"
    "bytes3"
    "bytes4"
    "bytes5"
    "bytes6"
    "bytes7"
    "bytes8"
    "bytes9"
    "bytes10"
    "bytes11"
    "bytes12"
    "bytes13"
    "bytes14"
    "bytes15"
    "bytes16"
    "bytes17"
    "bytes18"
    "bytes19"
    "bytes20"
    "bytes21"
    "bytes22"
    "bytes23"
    "bytes24"
    "bytes25"
    "bytes26"
    "bytes27"
    "bytes28"
    "bytes29"
    "bytes30"
    "bytes31"
    "bytes32"
    "int"
    "int8"
    "int16"
    "int24"
    "int32"
    "int40"
    "int48"
    "int56"
    "int64"
    "int72"
    "int80"
    "int88"
    "int96"
    "int104"
    "int112"
    "int120"
    "int128"
    "int136"
    "int144"
    "int152"
    "int160"
    "int168"
    "int176"
    "int184"
    "int192"
    "int200"
    "int208"
    "int216"
    "int224"
    "int232"
    "int240"
    "int248"
    "int256"

    "mapping"
    "real"
    "string"
    "text"

    "uint"
    "uint8"
    "uint16"
    "uint24"
    "uint32"
    "uint40"
    "uint48"
    "uint56"
    "uint64"
    "uint72"
    "uint80"
    "uint88"
    "uint96"
    "uint104"
    "uint112"
    "uint120"
    "uint128"
    "uint136"
    "uint144"
    "uint152"
    "uint160"
    "uint168"
    "uint176"
    "uint184"
    "uint192"
    "uint200"
    "uint208"
    "uint216"
    "uint224"
    "uint232"
    "uint240"
    "uint248"
    "uint256"

    "ureal")
  "Built in data types of the solidity language.")

(defconst solidity-builtin-constructs
  '("msg"
    "block"
    "tx")
  "Built in constructs of the solidity language.")

(defvar solidity-identifier-regexp
  "\\([a-zA-z0-9]\\|_\\)+")

(defvar solidity-variable-attributes
  "\\(&\\|*\\|~\\)"
  "Variable attributes like references '&' e.t.c.")

;; Set font lock options.
;; For information on the various faces check here:
;; http://www.gnu.org/software/emacs/manual/html_node/ccmode/Faces.html
;; For examples on how to make advanced fontification based on the
;; language rules check C mode here:
;; http://cc-mode.sourceforge.net/src/cc-fonts.el
;;
;; Guide for Searh based fontification:
;; http://ergoemacs.org/emacs_manual/elisp/Search_002dbased-Fontification.html
;; General colouring guide:
;; http://ergoemacs.org/emacs/elisp_syntax_coloring.html
(defconst solidity-font-lock-keywords
  (list
   `(,(regexp-opt solidity-tofontify-keywords 'words) . font-lock-keyword-face)
   `(,(regexp-opt solidity-builtin-types 'words) . font-lock-type-face)
   `(,(regexp-opt solidity-builtin-constructs 'words) . font-lock-builtin-face)
   '(solidity-match-functions (1 font-lock-type-face)
                              (2 font-lock-function-name-face))
   '(solidity-match-mappings (1 font-lock-type-face)
                             (3 font-lock-function-name-face))
   '(solidity-match-pragma-stmt (1 font-lock-preprocessor-face)
                                 (2 font-lock-string-face))
   '(solidity-match-library-decl (1 font-lock-keyword-face)
                                 (2 font-lock-variable-name-face))
   '(solidity-match-contract-decl (1 font-lock-keyword-face)
                                  (2 font-lock-variable-name-face))
   '(solidity-match-modifier-decl (1 font-lock-keyword-face)
                                (2 font-lock-variable-name-face))
   '(solidity-match-struct-decl (1 font-lock-keyword-face)
                                (2 font-lock-variable-name-face))
   '(solidity-match-event-decl (1 font-lock-keyword-face)
                                  (2 font-lock-variable-name-face))
   '(solidity-match-variable-decls (1 font-lock-keyword-face)
                                   (4 font-lock-variable-name-face))
   `(,(regexp-opt solidity-constants 'words) . font-lock-constant-face))
  "The font lock options for solidity.")

(defun solidity-match-regexp (re limit)
  "Generic regular expression matching wrapper for RE with a given LIMIT."
  (re-search-forward re
                     limit ; search bound
                     t     ; no error, return nil
                     nil   ; do not repeat
                     ))

(defun solidity-match-contract-decl (limit)
  "Search the buffer forward until LIMIT matching contract declarations.

First match should be a keyword and second an identifier."
  (solidity-match-regexp
   (concat
    " *\\(contract\\) +\\(" solidity-identifier-regexp "\\)")
   limit))

(defun solidity-match-library-decl (limit)
  "Search the buffer forward until LIMIT matching library declarations.

First match should be a keyword and second an identifier."
  (solidity-match-regexp
   (concat
    " *\\(library\\) +\\(" solidity-identifier-regexp "\\)")
   limit))

(defun solidity-match-pragma-stmt (limit)
  "Search the buffer forward until LIMIT matching pragma statements.

First match should be a keyword and second an identifier."
  (solidity-match-regexp
   (concat
    " *\\(pragma\\) +\\(.*\\);")
   limit))

(defun solidity-match-struct-decl (limit)
  "Search the buffer forward until LIMIT matching struct declarations.

First match should be a keyword and second an identifier."
  (solidity-match-regexp
   (concat
    " *\\(struct\\) +\\(" solidity-identifier-regexp "\\)")
   limit))

(defun solidity-match-functions (limit)
  "Search the buffer forward until LIMIT matching function names.

Highlight the 1st result."
  (solidity-match-regexp
   (concat
    " *\\(function\\) +\\(" solidity-identifier-regexp "\\)")
   limit))

(defun solidity-match-event-decl (limit)
  "Search the buffer forward until LIMIT matching function names.

Highlight the 1st result."
  (solidity-match-regexp
   (concat
    " *\\(event\\) +\\(" solidity-identifier-regexp "\\)")
   limit))

(defun solidity-match-modifier-decl (limit)
  "Search the buffer forward until LIMIT matching function names.

Highlight the 1st result."
  (solidity-match-regexp
   (concat
    " *\\(modifier\\) +\\(" solidity-identifier-regexp "\\)")
   limit))

(defun solidity-match-mappings (limit)
  "Search the buffer forward until LIMIT matching solidity mappings.

Highlight the 1st result."
  (solidity-match-regexp
   (concat
    " *\\(mapping\\) *(.*) *\\("(regexp-opt solidity-variable-modifier) " \\)*\\(" solidity-identifier-regexp "\\)")
   limit))

(defun solidity-match-variable-decls (limit)
  "Search the buffer forward until LIMIT matching variable declarations.

Highlight the 1st result."
  (solidity-match-regexp
   (concat
    " *\\(" (regexp-opt solidity-builtin-types) " *\\(\\[ *[0-9]*\\]\\)* *\\) " "\\("(regexp-opt solidity-variable-modifier) " \\)* *\\(" solidity-identifier-regexp "\\)")
   limit))

;; solidity syntax table
(defvar solidity-mode-syntax-table
  (let ((st (make-syntax-table)))
    ;; '_' underscore is a valid part of a word
    (modify-syntax-entry ?_ "w" st)
    ;; c++ style comments in the syntax table
    ;; more info on the syntax flags here:
    ;; http://www.gnu.org/software/emacs/manual/html_node/elisp/Syntax-Flags.html
    (modify-syntax-entry ?/ ". 124b" st)
    (modify-syntax-entry ?* ". 23" st)
    (modify-syntax-entry ?\n "> b" st)
    st)
  "Syntax table for the solidity language.")


(defun solidity--re-matches (regexp string count)
  "Get a list of all REGEXP match results in a STRING.

COUNT is the parenthentical subexpression for which to return matches.
If your provide 0 for COUNT then the entire regex match is returned."
  (save-match-data
    (let ((pos 0)
          matches)
      (while (string-match regexp string pos)
        (push (match-string-no-properties count string) matches)
        (setq pos (match-end 0)))
      matches)))

(defun solidity--handle-gasestimate-finish (process event)
  "Handle all events from the solc gas estimation PROCESS.
EVENT is isgnored."
  (when (memq (process-status process) '(signal exit))
    (let* ((buffer (process-buffer process))
           (funcname (process-get process 'solidity-gasestimate-for-function))
           (filename (process-get process 'solidity-gasestimate-for-filename))
           (output (with-current-buffer buffer (buffer-string)))
           (matches (solidity--re-matches (format "%s(.*?):.*?\\([0-9]+\\|infinite\\)" funcname) output 1))
           (result (car matches)))
      (kill-buffer buffer)
      (if (not result)
        (let* ((clearfilename (file-name-nondirectory filename))
               (ctor-matches (solidity--re-matches (format "=.*?%s:%s.*?=" clearfilename funcname) output 0)))
          (if ctor-matches
              (message "Gas estimate for '%s' constructor is %s" funcname (car (solidity--re-matches "construction:
.*?=.*?\\([0-9]+\\|infinite\\)" output 1)))
            ;;innermost else
            (message "No gas estimate found for '%s'" funcname)))
        ;; outermost else
        (message "Gas estimate for '%s' is %s" funcname result)))))


(defun solidity--start-gasestimate (func)
  "Start a gas estimation subprocess for FUNC.

Does not currently work for constructors."
  (let* ((filename (buffer-file-name))
         (command (format "%s --gas %s" solidity-solc-path filename))
         (process-name (format "solidity-command-%s" command))
         (process (start-process-shell-command
                   process-name
                   (format "*%s*" process-name)
                   command)))
    (set-process-query-on-exit-flag process nil)
    (set-process-sentinel process 'solidity--handle-gasestimate-finish)
    (process-put process 'solidity-gasestimate-for-function func)
    (process-put process 'solidity-gasestimate-for-filename filename)))

(defun solidity-estimate-gas-at-point ()
  "Estimate gas of the function at point.

Cursor must be at the function's name.  Does not currently work for constructors."
  (interactive)
  (solidity--start-gasestimate (thing-at-point 'symbol 'no-properties)))

;;;###autoload
(define-derived-mode solidity-mode c-mode "solidity"
  "Major mode for editing solidity language buffers."
  (set-syntax-table solidity-mode-syntax-table)
  ;; specify syntax highlighting
  (setq font-lock-defaults '(solidity-font-lock-keywords))

  ;; register indentation and other langue mode functions, basically the c-mode ones with some modifications
  (let ((start-value (if (eq solidity-comment-style 'star) "/* " "// "))
        (end-value (if (eq solidity-comment-style 'star) " */" "")))
    (set (make-local-variable 'comment-start) start-value)
    (set (make-local-variable 'comment-end) end-value))

  (make-local-variable 'comment-start-skip)

  (make-local-variable 'paragraph-start)
  (make-local-variable 'paragraph-separate)
  (make-local-variable 'paragraph-ignore-fill-prefix)
  (make-local-variable 'adaptive-fill-mode)
  (make-local-variable 'adaptive-fill-regexp)
  (make-local-variable 'fill-paragraph-handle-comment)

  ;; set values for some other variables
  (set (make-local-variable 'parse-sexp-ignore-comments) t)
  (set (make-local-variable 'indent-line-function) 'c-indent-line)
  (set (make-local-variable 'indent-region-function) 'c-indent-region)
  (set (make-local-variable 'normal-auto-fill-function) 'c-do-auto-fill)
  (set (make-local-variable 'comment-multi-line) t)
  (set (make-local-variable 'comment-line-break-function)
       'c-indent-new-comment-line)

  ;; set keymap
  (use-local-map solidity-mode-map)
  ;; set hooks
  (run-hooks 'solidity-mode-hook))

;;; --- interface with flycheck if existing ---
(when (require 'flycheck nil 'noerror)
  (require 'solidity-flycheck))

(provide 'solidity-mode)
;;; solidity-mode.el ends here