initial setup for view bindings

.gitignore

@@ -17,3 +17,5 @@ dev-resources/public/js/*.js
 *.*~
 .DS_Store
 dev-resources/.DS_Store
+testing/resources/public
+project/.generated

src/cljs/enfocus/bind.cljs

@@ -0,0 +1,30 @@
+(ns enfocus.bind
+  (:require
+   [enfocus.core :as ef :refer [from at set-attr get-attr]]))
+
+(defn- build-key [id]
+  (str "__EVB:" id))
+
+(defn bind-view-watch-fn [id render-func]
+  (fn [ctx ref oval nval]
+    (let [node (.getElementById js/document id)]
+      (if node
+        (render-func node nval)
+        (remove-watch ref (build-key id))))))
+
+
+
+(defn bind-view [atm render-func]
+  (fn [node]
+    (let [id (from node (get-attr :id))
+          nid (if (empty? id) (gensym "_EVB_") id)]
+      (when-not (= id nid) (at node (set-attr :id nid)))
+      (render-func node @atm)
+      (add-watch atm
+                 (build-key nid)
+                 (bind-view-watch-fn nid render-func)))))
+
+
+
+
+

test/cljs/enfocus/bind_test.cljs

@@ -0,0 +1,34 @@
+(ns enfocus.bind-test
+  (:require
+   [enfocus.core :as ef :refer [at from content get-text]]
+   [enfocus.bind :as bind :refer [bind-view]]
+   [cemerick.cljs.test :as t])
+  (:require-macros
+   [enfocus.macros :as em]
+   [cemerick.cljs.test :refer (is are deftest testing use-fixtures)]))
+
+(defn each-fixture [f]
+  ;; initialize the environment
+  (let [div (.createElement js/document "div")
+        pc (.createElement js/document "p")]
+    (.setAttribute div "id" "test-id")
+    (.setAttribute div "class" "test-class")
+    (.setAttribute pc "class" "test-class")
+    (.appendChild div pc)
+    (.appendChild (.-body js/document) div)
+    ;; execute the unit test
+    (f)
+    ;; clear the environment 
+    (.removeChild (.-body js/document) div)))
+
+(use-fixtures :each each-fixture)
+
+(deftest bind-view-test
+  (testing "binding a view to an atom"
+    (let [atm (atom "initial")]
+      (at "#test-id" (bind-view atm #(at %1 (content %2))))
+      (testing "initial value set"
+        (is (= "initial" (from "#test-id" (get-text)))))
+      (testing "updated value set"
+        (reset! atm "updated")
+        (is (= "updated" (from "#test-id" (get-text))))))))