Use ILIKE/LIKE for searching users

app/models/user.rb

@@ -286,8 +286,22 @@ class User < ActiveRecord::Base
       end
     end
 
+    # Searches users matching the given query.
+    #
+    # This method uses ILIKE on PostgreSQL and LIKE on MySQL.
+    #
+    # query - The search query as a String
+    #
+    # Returns an ActiveRecord::Relation.
     def search(query)
-      where("lower(name) LIKE :query OR lower(email) LIKE :query OR lower(username) LIKE :query", query: "%#{query.downcase}%")
+      table   = User.arel_table
+      pattern = "%#{query}%"
+
+      where(
+        table[:name].matches(pattern).
+          or(table[:email].matches(pattern)).
+          or(table[:username].matches(pattern))
+      )
     end
 
     def by_login(login)

spec/models/user_spec.rb

@@ -463,17 +463,43 @@ describe User, models: true do
     end
   end
 
-  describe 'search' do
-    let(:user1) { create(:user, username: 'James', email: 'james@testing.com') }
-    let(:user2) { create(:user, username: 'jameson', email: 'jameson@example.com') }
+  describe '.search' do
+    let(:user) { create(:user) }
 
-    it "should be case insensitive" do
-      expect(User.search(user1.username.upcase).to_a).to eq([user1])
-      expect(User.search(user1.username.downcase).to_a).to eq([user1])
-      expect(User.search(user2.username.upcase).to_a).to eq([user2])
-      expect(User.search(user2.username.downcase).to_a).to eq([user2])
-      expect(User.search(user1.username.downcase).to_a.size).to eq(2)
-      expect(User.search(user2.username.downcase).to_a.size).to eq(1)
+    it 'returns users with a matching name' do
+      expect(described_class.search(user.name)).to eq([user])
+    end
+
+    it 'returns users with a partially matching name' do
+      expect(described_class.search(user.name[0..2])).to eq([user])
+    end
+
+    it 'returns users with a matching name regarding of the casing' do
+      expect(described_class.search(user.name.upcase)).to eq([user])
+    end
+
+    it 'returns users with a matching Email' do
+      expect(described_class.search(user.email)).to eq([user])
+    end
+
+    it 'returns users with a partially matching Email' do
+      expect(described_class.search(user.email[0..2])).to eq([user])
+    end
+
+    it 'returns users with a matching Email regarding of the casing' do
+      expect(described_class.search(user.email.upcase)).to eq([user])
+    end
+
+    it 'returns users with a matching username' do
+      expect(described_class.search(user.username)).to eq([user])
+    end
+
+    it 'returns users with a partially matching username' do
+      expect(described_class.search(user.username[0..2])).to eq([user])
+    end
+
+    it 'returns users with a matching username regarding of the casing' do
+      expect(described_class.search(user.username.upcase)).to eq([user])
     end
   end