orzechowskid / flymake-eslint

Flymake backend for Javascript using eslint

flymake-eslint

Flymake backend for Javascript using eslint

Installation

0. Make sure eslint is installed and present on your emacs exec-path. For Linux systems exec-path usually equals your $PATH environment variable; for other systems, you're on your own.
1. Install:

• from MELPA: M-x package-install [RET] flymake-eslint [RET]
• manually: download and place inside ~/.emacs.d/lisp then edit ~/.emacs or equivalent:

(add-to-list 'load-path "~/.emacs.d/lisp")
(require "flymake-eslint.el")

2. Enable:

(add-hook 'web-mode-hook ; or whatever the mode-hook is for your mode of choice
  (lambda ()
    (flymake-eslint-enable)))

Customization

useful variables are members of the flymake-eslint group and can be viewed and modified with the command M-x customize-group [RET] flymake-eslint [RET].

(defcustom flymake-eslint-executable-name "eslint"
  "Name of executable to run when checker is called.  Must be present in variable `exec-path'."
  :type 'string
  :group 'flymake-eslint)

(defcustom flymake-eslint-executable-args nil
  "Extra arguments to pass to eslint."
  :type 'string
  :group 'flymake-eslint)

(defcustom flymake-eslint-show-rule-name t
  "Set to t to append rule name to end of warning or error message, nil otherwise."
  :type 'boolean
  :group 'flymake-eslint)
  
(defcustom flymake-eslint-defer-binary-check nil
  "Set to t to bypass the initial check which ensures eslint is present.

Useful when the value of variable `exec-path' is set dynamically and the location of eslint might not be known ahead of time."
  :type 'boolean
  :group 'flymake-eslint)

(defcustom flymake-eslint-project-root nil
  "Buffer-local.  Set to a filesystem path to use that path as the current working directory of the linting process."
  :type 'string
  :group 'flymake-eslint)
  
(defcustom flymake-eslint-prefer-json-diagnostics nil
  "Try to use the JSON diagnostic format when runnin ESLint.
This gives more accurate diagnostics but requires having an Emacs
version with JSON support."
  :type 'boolean
  :group 'flymake-eslint)

Bugs

yes

See Also

flymake-stylelint

License

MIT

flymake-eslint's Issues

Melpa?

Could you provide your package on melpa.org?

Thanks!

Can’t initialize automatically with EGLOT

With the setup below I get the following error in my *Messages* buffer: Error in process sentinel: Can’t find state for flymake-eslint—checker in ‘flymake—state’ [2 times]. I do not get this error when I run flymake-eslint-enable manually, though. Is there any workaround or reason as to why this is happening? I have eslint on my PATH and I am using Node version 16.15.1.

(use-package flymake-eslint
:config
    (add-hook 'js-mode-hook (lambda () (flymake-eslint-enable)))
    (add-hook ‘js-mode-hook (lambda () (eglot-ensure))) ;; this will be run first
)

The eglot-ensure will run first. If I try and switch the order, eglot decides to override the flymake backends, making eglot the only backend. I can then run flymake-eslint-enable, but that defeats the purpose of what I want…If I remove the eglot line altogether, then this package works as intended, still not what I want…I am enabling js-mode manually in all these tests.

When using a eslint binary installed locally with direnv it doesn't work

If by chance flymake-eslint-enable happens to execute before the hook that adds the direnv things to path it will fail to enable flymake-eslint. I have run into this where I add (eval . (flymake-eslint-enable)) to a .dir-locals.el file. At the time where the check for the binary is run it is not available yet. If I later run the command it will of course work. Perhaps it should be possible to add the checker to flymake-diagnostic-functions even though the binary is not available.

Either make this behavior configurable or perhaps add the check for the binary to a later stage, e.g. during the checking, as a pre-condition or similar.

temp files stick around after eslint is done

...I should do something about that.

flymake-eslint-executable-args doesn't do anything

Allow running ESLint using npx

Currently, ESLint needs to be in executable-path, which means that ESLint must be installed globally or executable-path has to be configured per project. It would be nice if flymake-eslint would offer the possibility to run ESLint through NPM's npx command instead (npx eslint), which would automatically pick up the ESLint version installed in the project's node_modules, and only runs the globally installed version as a fallback.

pipe input to eslint via stdin with --stdin

and figure out how to apply .eslintrc (and potentially babel-eslint) to it

Flymake crashes with "Unexpected report from disabled backend"

This is an incomplete bug report as I don't know what's causing the problem.

As soon as I'm causing a linting violation in a file (and save that file), the following is printed to *Messages*:

error in process sentinel: flymake-error: [Flymake] Unexpected report from disabled backend flymake-eslint--checker
error in process sentinel: [Flymake] Unexpected report from disabled backend flymake-eslint--checker

Trying to go to the next error fails with the following message:

user-error: No more Flymake diagnostics

flymake-eslint is in my package-selected-packages in my init file. I'm using the following config:

(setq exec-path (append exec-path '("/path/to/project/node_modules/eslint/bin")))
(setq flymake-eslint-executable-name "/path/to/project/node_modules/eslint/bin/eslint.js")
(add-hook 'js-mode-hook (lambda ()
                          (flymake-eslint-enable)))
(add-hook 'js-mode-hook
	      (lambda()
	        (local-set-key (kbd "C-c C-f") 'flymake-goto-next-error)))

I'm using [email protected] and node version v16.9.1 with GNU Emacs 27.2 on Manjaro. I'm not sure what additional information to provide. Please tell me.

`flymake-eslint-enable` works when enabled from minibuffer but fails when started from major mode hook

Here's my config

(use-package flymake
  :ensure flymake
  :demand
  :hook (prog-mode . flymake-mode)
  :defines
  flymake-mode
  :bind
  ("M-n"     . flymake-goto-next-error)
  ("M-p"     . flymake-goto-prev-error)
  ("<f12>"   . flymake-goto-next-error)
  ("C-<f12>" . flymake-goto-next-error)
  ("C-c !"   . flymake-show-buffer-diagnostics))

(use-package flymake-eslint
  :ensure flymake-eslint
  :after (flymake)
  :hook
  (js2-mode . flymake-eslint-enable)
  (web-mode . flymake-eslint-enable)
  (typescript-ts-mode .  (lambda () (flymake-eslint-enable)))
  (tsx-ts-mode . (lambda () (flymake-eslint-enable))))

If I open a ts or tsx file and then I do M-x flymake-eslint-enable it works
But as a hook trigger from the above config it fails

Note: It's now written with lambda as I hoped that would solve it but I get the same error if have hooks configured like

(mode . flymake-eslint-enable)

I'm using treesitter & eglot

Messages Log

error in process sentinel: flymake--handle-report: Can’t find state for flymake-proc-legacy-flymake in ‘flymake--state’
error in process sentinel: Can’t find state for flymake-proc-legacy-flymake in ‘flymake--state’
error in process sentinel: flymake--handle-report: Can’t find state for flymake-eslint--checker in ‘flymake--state’
error in process sentinel: Can’t find state for flymake-eslint--checker in ‘flymake--state’

Is it possible to run it from project's root?

My eslint configuration file has the parserOptions.project property defined to ./tsconfig.json.

This breaks when flymake-eslint runs eslint because, if I'm not mistaken, it does so from the directory containing the file the buffer is visiting as there's no ./tsconfig.json there (but some directories up).

Error reported when running flymake-eslint-enable is

/home/marcos/Projects/Sandbox/flymake-eslint-error/test/foo/bar/miau.ts
  0:0  error  Parsing error: File '/home/marcos/Projects/Sandbox/flymake-eslint-error/test/foo/bar/tsconfig.json' not found

✖ 1 problem (1 error, 0 warnings)```

Any hint on how to workaround it or fixing guidelines will be appreciated.

Thanks!

GPL?

Would like to know why the package is released under MIT?

Using `buffer-name` causes potential errors

buffer-name does not always return the actual file-name. If you have multiple buffers with the same conflicting name it could be renamed, as well as personally I have custom code displaying different buffer-name based on project.

E.g.

(defun +projectile-relative-buf-name ()
  (when (buffer-file-name)
    (let ((buffer-name (if (projectile-project-p)
                           (concat (projectile-project-name) "/" (file-relative-name (buffer-file-name) (projectile-project-root)))
                         (abbreviate-file-name (buffer-file-name)))))
      (rename-buffer buffer-name t))))
(add-hook 'find-file-hook #'+projectile-relative-buf-name)

In those cases you will get, since the buffer-name is passed as --stdin-filename:

Error: ENOENT: no such file or directory, scandir '/path/to/src/code'

One work-around is to instead use buffer-file-name which will give the absolute path to the file.

When eslint fails flymake highlights whole buffer in red

It should be probably only first line

project-root void error

On emacs 27.2 project-root function not available. Can be fixed by installing project package from GNU ELPA.