Add localstorage implementation

adambeynon · adambeynon · commit eab45e24ed11 · 2014-01-14T09:21:52.000Z
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -5,6 +5,8 @@
 *   Add `Event` methods: `prevented?`, `prevent`, `stopped?` and `stop` to
     replace longer javascript names.
 
+*   Add `LocalStorage` implementation.
+
 ## 0.1.2 2013-12-01
 
 *   Support setting html content through `Element#html()`.
diff --git a/opal/opal-jquery/local_storage.rb b/opal/opal-jquery/local_storage.rb
@@ -0,0 +1,28 @@
+module DOM
+  class LocalStorage
+    def initialize(storage)
+      @storage = storage
+    end
+
+    def []=(key, value)
+      `#@storage.setItem(key, value)`
+    end
+
+    def [](key)
+      %x{
+        var value = #@storage.getItem(key);
+        return value == null ? nil : value;
+      }
+    end
+
+    def delete(key)
+      `#@storage.removeItem(key)`
+    end
+
+    def clear
+      `#@storage.clear()`
+    end
+  end
+end
+
+LocalStorage = DOM::LocalStorage.new(`window.localStorage`)
diff --git a/spec/local_storage_spec.rb b/spec/local_storage_spec.rb
@@ -0,0 +1,22 @@
+require 'spec_helper'
+require 'opal-jquery/local_storage'
+
+describe LocalStorage do
+  before { subject.clear }
+
+  it "returns nil for undefined values" do
+    expect(subject['foo']).to be_nil
+  end
+
+  it "should be able to create items" do
+    subject['foo'] = 'Ford Prefect'
+    expect(subject['foo']).to eq('Ford Prefect')
+  end
+
+  it "should be able to delete items" do
+    subject['name'] = 'Arthur'
+    subject.delete 'name'
+
+    expect(subject['name']).to be_nil
+  end
+end
