From f2a90afa4cd0c770aef51b14c6538f9d9a07f452 Mon Sep 17 00:00:00 2001
From: Alan Guo Xiang Tan <gxtan1990@gmail.com>
Date: Mon, 23 Oct 2023 07:41:40 +0800
Subject: [PATCH] DEV: Introduce `Theme#get_setting` (#24032)

Why this change?

Currently, we do not have a method to easily retrieve a theme setting's
value on the server side. Such a method can be useful in the test
environment where we need to retrieve the theme's setting and use its
value in assertions.

What does this change do?

This change introduces the `Theme#get_setting` instance method.
---
 app/models/theme.rb       | 20 ++++++++++++++++++++
 spec/models/theme_spec.rb | 31 +++++++++++++++++++++++++++++++
 2 files changed, 51 insertions(+)

diff --git a/app/models/theme.rb b/app/models/theme.rb
index 87b566c3073..bdba5fc67a3 100644
--- a/app/models/theme.rb
+++ b/app/models/theme.rb
@@ -699,6 +699,26 @@ class Theme < ActiveRecord::Base
     hash
   end
 
+  # Retrieves a theme setting
+  #
+  # @param setting_name [String, Symbol] The name of the setting to retrieve.
+  #
+  # @return [Object] The value of the setting that matches the provided name.
+  #
+  # @raise [Discourse::NotFound] If no setting is found with the provided name.
+  #
+  # @example
+  #   theme.get_setting("some_boolean") => True
+  #   theme.get_setting("some_string") => "hello"
+  #   theme.get_setting(:some_boolean) => True
+  #   theme.get_setting(:some_string) => "hello"
+  #
+  def get_setting(setting_name)
+    target_setting = settings.find { |setting| setting.name == setting_name.to_sym }
+    raise Discourse::NotFound unless target_setting
+    target_setting.value
+  end
+
   def update_setting(setting_name, new_value)
     target_setting = settings.find { |setting| setting.name == setting_name }
     raise Discourse::NotFound unless target_setting
diff --git a/spec/models/theme_spec.rb b/spec/models/theme_spec.rb
index 6ffa42b4fcf..27498852276 100644
--- a/spec/models/theme_spec.rb
+++ b/spec/models/theme_spec.rb
@@ -1040,6 +1040,37 @@ HTML
     end
   end
 
+  describe "get_setting" do
+    before do
+      theme.set_field(target: :settings, name: "yaml", value: <<~YAML)
+        enabled:
+          type: bool
+          default: false
+        some_value:
+          type: string
+          default: "hello"
+      YAML
+
+      ThemeSetting.create!(
+        theme: theme,
+        data_type: ThemeSetting.types[:bool],
+        name: "super_feature_enabled",
+      )
+
+      theme.save!
+    end
+
+    it "returns the value of the setting when given a string represeting the setting name" do
+      expect(theme.get_setting("enabled")).to eq(false)
+      expect(theme.get_setting("some_value")).to eq("hello")
+    end
+
+    it "returns the value of the setting when given a symbol represeting the setting name" do
+      expect(theme.get_setting(:enabled)).to eq(false)
+      expect(theme.get_setting(:some_value)).to eq("hello")
+    end
+  end
+
   describe "#update_setting" do
     it "requests clients to refresh if `refresh: true`" do
       theme.set_field(target: :settings, name: "yaml", value: <<~YAML)