Fix Ruby 3.4 frozen string literal warning

README.md

@@ -71,8 +71,17 @@ Geohash.walk 'xn774c', [
 ```
 
 
+Development
+-----------
+
+```bash
+bundle install
+bundle exec rake test
+```
+
+
 License
 -------
 
-This project is copyright by [Creasty](http://www.creasty.com), released under the MIT lisence.  
+This project is copyright by [Creasty](http://www.creasty.com), released under the MIT license.
 See `LICENSE` file for details.

Rakefile

@@ -1,2 +1,9 @@
 require 'bundler/gem_tasks'
+require 'rake/testtask'
+
+Rake::TestTask.new do |t|
+  t.pattern = 'test/**/*_test.rb'
+end
+
+task default: :test
 

geohash_ruby.gemspec

@@ -18,6 +18,7 @@ Gem::Specification.new do |spec|
   spec.test_files    = spec.files.grep(%r{^(test|spec|features)/})
   spec.require_paths = ['lib']
 
-  spec.add_development_dependency 'bundler', '~> 1.6'
-  spec.add_development_dependency 'rake', '~> 10.3'
+  spec.add_development_dependency 'bundler'
+  spec.add_development_dependency 'rake'
+  spec.add_development_dependency 'minitest'
 end

lib/geohash_ruby.rb

@@ -79,7 +79,7 @@ def encode(latitude, longitude, precision = 12)
     mids = [latitude, longitude]
     bounds = [[-90.0, +90.0], [-180.0, +180.0]]
 
-    geohash = ''
+    geohash = []
 
     precision.times do |i|
       d = 0
@@ -95,7 +95,7 @@ def encode(latitude, longitude, precision = 12)
       geohash << BASE32[d]
     end
 
-    geohash
+    geohash.join
   end
 
   ###

test/geohash_ruby_test.rb

@@ -0,0 +1,8 @@
+require "minitest/autorun"
+require_relative "../lib/geohash_ruby"
+
+class GeohashRubyTest < Minitest::Test
+  def test_encode
+    assert_equal "xn76ggke6xs5", Geohash.encode(35.6581, 139.7414)
+  end
+end