From: John Wiegley <johnw@newartisans.com>
Date: Fri, 26 Feb 2016 01:24:59 +0000 (-0800)
Subject: Add configuration variable `use-package-check-before-init'
X-Git-Tag: emacs-29.0.90~1306^2~15^2~304
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=6a90a9f16d;p=emacs.git

Add configuration variable `use-package-check-before-init'

Fixes https://github.com/jwiegley/use-package/issues/306
---

diff --git a/lisp/use-package/use-package.el b/lisp/use-package/use-package.el
index 619c6c3b3f3..617c523f8ff 100644
--- a/lisp/use-package/use-package.el
+++ b/lisp/use-package/use-package.el
@@ -66,9 +66,15 @@ then the expanded macros do their job silently."
   :type 'boolean
   :group 'use-package)
 
+(defcustom use-package-check-before-init nil
+  "If non-nil, check that package exists before executing its `:init' block.
+The check is performed by looking for the module using `locate-library'."
+  :type 'boolean
+  :group 'use-package)
+
 (defcustom use-package-always-defer nil
   "If non-nil, assume `:defer t` unless `:demand t` is given."
-  :type 'sexp
+  :type 'boolean
   :group 'use-package)
 
 (defcustom use-package-always-ensure nil
@@ -938,7 +944,13 @@ deferred until the prefix key sequence is pressed."
   (let ((body (use-package-process-keywords name rest state)))
     (use-package-concat
      ;; The user's initializations
-     (use-package-hook-injector (use-package-as-string name) :init arg)
+     (let ((init-body
+            (use-package-hook-injector (use-package-as-string name)
+                                       :init arg)))
+       (if use-package-check-before-init
+           `((if (locate-library ,(use-package-as-string name))
+                 ,(macroexp-progn init-body)))
+         init-body))
      body)))
 
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