Separate home service into PIM, dev env and graphical parts

This means we only instantiate Shepherd and mcron services if we really need
them, to avoid annoyance on servers.

1 files changed, 123 insertions, 0 deletions

diff --git a/tw/services/files/emacs-packages/flymake-guile.el b/tw/services/files/emacs-packages/flymake-guile.el
new file mode 100644
index 00000000..edfbce82
--- /dev/null
+++ b/tw/services/files/emacs-packages/flymake-guile.el
@@ -0,0 +1,123 @@
+;;; flymake-guile.el --- Flymake checker using `guild compile'  -*- lexical-binding: t -*-
+;;; Commentary:
+;;; "guild compile" compiles Guile code to bytecode and can output a few basic
+;;; warnings.  Let's use this as a linter!
+;;; Code:
+
+(require 'custom)
+(require 'flymake)
+(require 'geiser-impl)   ; for `geiser-active-implementations'
+
+(defcustom flymake-guile-guild-executable "guild"
+  "The guild executable to use.  This will be looked up in $PATH."
+  :type '(string)
+  :risky t
+  :group 'flymake-guile)
+
+(defvar-local flymake-guile--flymake-proc nil
+  "The latest invocation of guild compile.")
+
+(defvar-local flymake-guile--temp-file nil
+  "The temporary file name to pass to guild.")
+
+(defun flymake-guile--encode-filename (buffer-name)
+  "Create a safe temporary file name from BUFFER-NAME."
+  (concat "/tmp/flymake-guile-"
+          (string-replace
+           "/" "!"   ; we don't want to create subdirs under /tmp
+           (or buffer-name
+               (format "temp-%s.scm"
+                       (random most-positive-fixnum))))))
+
+;; See info node: (flymake)An annotated example backend.
+(defun flymake-guile (report-fn &rest _args)
+  "Run guild compile and report diagnostics from it using REPORT-FN.
+Any running invocations are killed before running another one."
+  (unless (executable-find flymake-guile-guild-executable)
+    (funcall report-fn :panic
+             :explanation "Cannot find `flymake-guile-guild-executable' program")
+    (error "Cannot find guild executable"))
+
+  (unless flymake-guile--temp-file
+    (setq-local flymake-guile--temp-file (flymake-guile--encode-filename (buffer-file-name))))
+
+  ;; Kill previous check, if it's still running.
+  (when (process-live-p flymake-guile--flymake-proc)
+    (kill-process flymake-guile--flymake-proc))
+
+  ;; This needs `lexical-binding'.
+  (let ((source (current-buffer))
+        ;; Copy `flymake-guile--temp-file' to a local var so that we can refer to it in the `lambda' below.
+        (temp-file flymake-guile--temp-file))
+    (save-restriction
+      (widen)
+      ;; Send the buffer to guild on stdin.
+      (with-temp-file flymake-guile--temp-file
+        (insert-buffer-substring-no-properties source))
+      (setq flymake-guile--flymake-proc
+            (make-process
+             :name "flymake-guild" :noquery t :connection-type 'pipe
+             ;; Direct output to a temporary buffer.
+             :buffer (generate-new-buffer " *flymake-guile*")
+             ;; Guild can't read from stdin; it needs a file.
+             :command (list flymake-guile-guild-executable "compile"
+                            ;; See "guild --warn=help" for details.
+                            ;; "--warn=unsupported-warning"  ; ignore unsupported warning types
+                            ;; "--warn=unused-variable"  ; too many false positives from macros
+                            "--warn=unused-toplevel"
+                            "--warn=shadowed-toplevel"
+                            "--warn=unbound-variable"
+                            "--warn=macro-use-before-definition"
+                            "--warn=use-before-definition"
+                            "--warn=non-idempotent-definition"
+                            "--warn=arity-mismatch"
+                            "--warn=duplicate-case-datum"
+                            "--warn=bad-case-datum"
+                            "--warn=format"
+                            "-L" (expand-file-name
+                                  (project-root (project-current nil (file-name-directory
+                                                                      (buffer-file-name source)))))
+                            flymake-guile--temp-file)
+             :sentinel
+             (lambda (proc _event)
+               "Parse diagnostic messages once the process PROC has exited."
+               ;; Check the process has actually exited, not just been suspended.
+               (when (memq (process-status proc) '(exit signal))
+                 (unwind-protect
+                     ;; Only proceed if we've got the "latest" process.
+                     (if (with-current-buffer source (not (eq proc flymake-guile--flymake-proc)))
+                         (flymake-log :warning "Canceling obsolete check %s" proc)
+                       (with-current-buffer (process-buffer proc)
+                         (goto-char (point-min))
+                         (cl-loop
+                          with msg-regexp = (rx bol (literal temp-file) ":"          ; filename
+                                                (group (+ digit)) ":"                ; line
+                                                (group (+ digit)) ": "               ; column
+                                                (group (or "warning" "error")) ": "  ; type
+                                                (group (+ not-newline)) eol)         ; message
+                          while (search-forward-regexp msg-regexp nil t)
+                          for (beg . end) = (flymake-diag-region
+                                             source   ; we filter for messages matching our buffer in the regexp
+                                             (string-to-number (match-string 1))
+                                             ;; guild outputs 0-based column numbers
+                                             (1+ (string-to-number (match-string 2))))
+                          for type = (pcase (match-string 3)
+                                       ("warning" :warning)
+                                       ("error" :error)
+                                       (type (error "Unknown guild error type %s" type)))
+                          collect (flymake-make-diagnostic source beg end type (match-string 4))
+                          into diags
+                          finally (funcall report-fn diags))))
+                   ;; Clean up temporary buffer.
+                   (kill-buffer (process-buffer proc))
+                   (delete-file temp-file)))))))))
+
+(defun flymake-guile-enable ()
+  "Set up the Guile checker for flymake, if in a Guile buffer."
+  (when (memq 'guile geiser-active-implementations)
+    (add-hook 'flymake-diagnostic-functions #'flymake-guile nil t)))
+
+(add-hook 'scheme-mode-hook #'flymake-guile-enable)
+
+(provide 'flymake-guile)
+;;; flymake-guile.el ends here