From 36eb08a8c7667b8bf5447cbfccebff95b33920af Mon Sep 17 00:00:00 2001
From: vu-hoang-kaligo <vu.hoang@kaligo.com>
Date: Mon, 13 Jan 2025 08:15:34 +0700
Subject: [PATCH] Support testing by mocking MockRedis#evalsha

---
 Gemfile.lock                       |  2 +-
 README.md                          | 11 +++++++++++
 lib/idempotency/testing/helpers.rb | 29 +++++++++++++++++++++++++++++
 lib/idempotency/version.rb         |  2 +-
 4 files changed, 42 insertions(+), 2 deletions(-)
 create mode 100644 lib/idempotency/testing/helpers.rb

diff --git a/Gemfile.lock b/Gemfile.lock
index d15265e..7191e9e 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -1,7 +1,7 @@
 PATH
   remote: .
   specs:
-    idempotency (0.1.2)
+    idempotency (0.1.3)
       base64
       dry-configurable
       msgpack
diff --git a/README.md b/README.md
index a787551..a29d961 100644
--- a/README.md
+++ b/README.md
@@ -89,3 +89,14 @@ end
 
 # Render your response
 ```
+
+### Testing
+
+For those using `mock_redis` gem, some methods that `idempotency` gem uses are not implemented (e.g. eval, evalsha), and this could cause test cases to fail. To get around this, the gem has a monkeypatch over `mock_redis` gem to override the missing methods. To use it, simply add following lines to your `spec_helper.rb`:
+
+```ruby
+RSpec.configure do |config|
+  config.include Idempotency::Testing::Helpers
+end
+```
+
diff --git a/lib/idempotency/testing/helpers.rb b/lib/idempotency/testing/helpers.rb
new file mode 100644
index 0000000..655a99b
--- /dev/null
+++ b/lib/idempotency/testing/helpers.rb
@@ -0,0 +1,29 @@
+# frozen_string_literal: true
+
+require 'idempotency/cache'
+
+class Idempotency
+  module Testing
+    module Helpers
+      def self.included(_base)
+        return unless defined?(MockRedis)
+
+        MockRedis.class_eval do
+          def evalsha(sha, keys:, argv:)
+            return unless sha == Idempotency::Cache::COMPARE_AND_DEL_SCRIPT_SHA
+
+            value = argv[0]
+            cached_value = get(keys[0])
+
+            if value == cached_value
+              del(keys[0])
+              value
+            else
+              cached_value
+            end
+          end
+        end
+      end
+    end
+  end
+end
diff --git a/lib/idempotency/version.rb b/lib/idempotency/version.rb
index 7220cf3..d8744e3 100644
--- a/lib/idempotency/version.rb
+++ b/lib/idempotency/version.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
 
 class Idempotency
-  VERSION = '0.1.2'
+  VERSION = '0.1.3'
 end