Merge hash instead of replacing the original value in user_context

lib/raven/instance.rb

@@ -177,7 +177,13 @@ def annotate_exception(exc, options = {})
     #   Raven.user_context('id' => 1, 'email' => 'foo@example.com')
     def user_context(options = nil)
       original_user_context = context.user
-      context.user = options || {}
+
+      if options
+        context.user.merge!(options)
+      else
+        context.user = {}
+      end
+
       yield if block_given?
       context.user
     ensure

spec/raven/instance_spec.rb

@@ -247,6 +247,12 @@ def ivars(object)
 
   describe "#user_context" do
     context "without a block" do
+      it "doesn't override previous data" do
+        subject.user_context(id: 1)
+        subject.user_context(email: "test@example.com")
+
+        expect(subject.context.user).to eq({ id: 1, email: "test@example.com" })
+      end
       it "empties the user context when called without options" do
         subject.context.user = { id: 1 }
         expect(subject.user_context).to eq({})
@@ -257,9 +263,9 @@ def ivars(object)
         expect(subject.user_context(nil)).to eq({})
       end
 
-      it "empties the user context when called with {}" do
+      it "doesn't empty the user context when called with {}" do
         subject.context.user = { id: 1 }
-        expect(subject.user_context({})).to eq({})
+        expect(subject.user_context({})).to eq({ id: 1 })
       end
 
       it "returns the user context when set" do