Emacs clean up.

config/emacs/modules/build.el

@@ -2,16 +2,17 @@
 ;;; Commentary:
 ;; Loaded from init.el after Evil.
 ;;
-;;   :build        Run ./build.sh from the project root.
+;;   :build        Run ./build.sh from the nearest ancestor dir containing it.
 ;;   :build ARGS   Run ./build.sh ARGS, e.g. :build release -v
 ;;
+;; If no build.sh is found (or it isn't executable), report it and do nothing.
+;;
 ;; The compilation buffer opens at the bottom (45% height, full width) and
 ;; takes focus when the build starts. ANSI colours are rendered.
 ;; Kill a running build with M-x kill-compilation.
 ;;; Code:
 
-(setq compile-command "./build.sh"
-      compilation-read-command nil          ; run without prompting
+(setq compilation-read-command nil          ; run without prompting
       compilation-ask-about-save nil
       compilation-scroll-output t)
 
@@ -31,10 +32,15 @@
 
 ;; :build runs ./build.sh; :build ARGS appends ARGS.
 (evil-define-command my/ex-build (args)
-  "Run `./build.sh ARGS' from the project root."
+  "Run `./build.sh ARGS' from the nearest directory containing build.sh."
   (interactive "<a>")
-  (let ((compile-command (concat "./build.sh " args)))   ; nil args -> ""
-    (project-compile)))
+  (let ((root (locate-dominating-file default-directory "build.sh")))
+    (unless root
+      (user-error "No build.sh found"))
+    (let ((default-directory root))
+      (unless (file-executable-p "build.sh")
+        (user-error "build.sh is not executable"))
+      (compile (string-trim (concat "./build.sh " args))))))   ; nil args -> ""
 
 (evil-ex-define-cmd "build" #'my/ex-build)