allow @ and + characters for search

Library/Homebrew/search.rb

@@ -150,7 +150,7 @@ module Homebrew
     end
 
     def self.simplify_string(string)
-      string.downcase.gsub(/[^a-z\d]/i, "")
+      string.downcase.gsub(/[^a-z\d@+]/i, "")
     end
 
     def self.search_regex(selectable, regex)

Library/Homebrew/test/search_spec.rb

@@ -20,7 +20,7 @@ RSpec.describe Homebrew::Search do
   end
 
   describe "#search" do
-    let(:collection) { ["with-dashes"] }
+    let(:collection) { ["with-dashes", "with@alpha", "with+plus"] }
 
     context "when given a block" do
       let(:collection) { [["with-dashes", "withdashes"]] }
@@ -41,6 +41,11 @@ RSpec.describe Homebrew::Search do
       it "simplifies both the query and searched strings" do
         expect(described_class.search(collection, "with dashes")).to eq ["with-dashes"]
       end
+
+      it "does not simplify strings with @ and + characters" do
+        expect(described_class.search(collection, "with@alpha")).to eq ["with@alpha"]
+        expect(described_class.search(collection, "with+plus")).to eq ["with+plus"]
+      end
     end
 
     context "when searching a Hash" do