Don't clobber any existing :custom-init configuration

Leiningen doesn't know how to merge this option - see technomancy/leiningen#878.
Instead, use ^:replace metadata to overwrite it completely with a form that
evaluates any existing value before evaluating our init code.

src/whidbey/plugin.clj

@@ -18,14 +18,17 @@
 
 (defn- whidbey-profile
  "Constructs a profile map for enabling the repl hooks."
- [version options]
- (->
- `{:dependencies [[mvxcvi/whidbey ~(or version "RELEASE")]]
- :repl-options {:custom-init (do (require 'whidbey.repl)
- (whidbey.repl/init! ~options))
- ;; :printer is nrepl 0.5.x only
- :nrepl-context {:interactive-eval {:printer whidbey.repl/render-str}}}}
- (vary-meta assoc :repl true)))
+ [project]
+ (let [version (find-plugin-version project 'mvxcvi/whidbey)
+ options (:whidbey project)
+ custom-init (get-in project [:repl-options :custom-init])]
+ (-> `{:dependencies [[mvxcvi/whidbey ~(or version "RELEASE")]]
+ :repl-options {:custom-init ^:replace (do ~custom-init
+ (require 'whidbey.repl)
+ (whidbey.repl/init! ~options))
+ ;; :printer is nrepl 0.5.x only
+ :nrepl-context {:interactive-eval {:printer whidbey.repl/render-str}}}}
+ (vary-meta assoc :repl true))))
 
 
 (defn repl-pprint
@@ -35,7 +38,5 @@
  [project]
  (if (:whidbey/repl (:profiles project))
  project
- (let [options (:whidbey project)
- version (find-plugin-version project 'mvxcvi/whidbey)
- profile (whidbey-profile version options)]
+ (let [profile (whidbey-profile project)]
  (project/add-profiles project {:whidbey/repl profile}))))