Consider merging exact key feature

lib/gpgme/key.rb

@@ -63,6 +63,26 @@ def find(secret, keys_or_names = nil, purposes = [])
         keys
       end
 
+      # Works similar as {.find}, however it restricts the way the keys are looked up.
+      # GPG has the issue that finding a key for bar@example.com, also returns a key
+      # for foobar@example.com.
+      # This can be restricted by adding <> around the address: <bar@example.com>.
+      # Hence {.find_exact} simply wraps <> around each email you passed to the method and delegates
+      # the rest to {.find}
+      #
+      # @example
+      #   GPGME::Key.find_exact(:public, "bar@example.com")
+      #   # => return the public key of bar@example.com, but not for
+      #   #    foobar@example.com
+      def find_exact(secret, keys_or_names = nil, purposes = [])
+        keys_or_names = [""] if keys_or_names.nil? || (keys_or_names.is_a?(Array) && keys_or_names.empty?)
+        find(
+          secret,
+          [keys_or_names].flatten.collect{|k| if k =~ /.*@.*/ && !(k =~ /<.*@.*>/) then "<#{k}>" else k end },
+          purposes
+        )
+      end
+
       def get(fingerprint)
         Ctx.new do |ctx|
           ctx.get_key(fingerprint)

test/key_test.rb

@@ -53,6 +53,28 @@
       assert keys.empty?
     end
   end
+
+  describe :find_exact do
+    it "wraps an email address with angle brackets" do
+      GPGME::Key.expects(:find).with(:public,['<bar@example.com>'],[])
+      GPGME::Key.find_exact(:public,'bar@example.com')
+    end
+
+    it "wraps multiple email addresses with angle brackets" do
+      GPGME::Key.expects(:find).with(:public,['<bar@example.com>','<foo@example.com>'],[])
+      GPGME::Key.find_exact(:public,['bar@example.com','foo@example.com'])
+    end
+
+    it "does not touch other strings than email addresses" do
+      GPGME::Key.expects(:find).with(:public,['Bar Example'],[])
+      GPGME::Key.find_exact(:public,'Bar Example')
+    end
+
+    it "does the same in mixed mode" do
+      GPGME::Key.expects(:find).with(:public,['<bar@example.com>','Foo Example'],[])
+      GPGME::Key.find_exact(:public,['bar@example.com','Foo Example'])
+    end
+  end
 
   describe :export do
     # Testing the lazy way with expectations. I think tests in