Initial concept

lib/liquid.rb

@@ -75,6 +75,7 @@ require 'liquid/utils'
 require 'liquid/tokenizer'
 require 'liquid/parse_context'
 require 'liquid/partial_cache'
+require 'liquid/usage'
 
 # Load all the tags of the standard library
 #

lib/liquid/usage.rb

@@ -0,0 +1,19 @@
+module Liquid
+  # Usage is used to store
+  class Usage
+    @messages = {}
+    class << self
+      def enable
+        Dir["#{__dir__}/usages/*.rb"].each { |f| require f }
+      end
+
+      def track(message)
+        @messages[message] = true
+      end
+
+      def results
+        @messages
+      end
+    end
+  end
+end

lib/liquid/usages/usage_enabled.rb

@@ -0,0 +1 @@
+Liquid::Usage.track("Usage is enabled")

test/integration/usage_test.rb

@@ -0,0 +1,34 @@
+require 'test_helper'
+
+module Liquid
+  class TestUsage < Usage
+    @messages = {}
+    class << self
+      def enable
+        Dir["#{__dir__}/usages/*.rb"].each { |f| require f }
+      end
+    end
+  end
+end
+
+class UsageTest < Minitest::Test
+  include Liquid
+
+  Usage.enable
+
+  def test_test_usages
+    Dir["#{__dir__}/usages/*.rb"].each { |f| require f }
+
+    template = Template.parse(%({{test}}))
+    assert_equal 'worked', template.render!('test' => 'worked')
+    assert_equal 'worked wonderfully', template.render!('test' => 'worked wonderfully')
+    assert_equal true, Usage.results["Using try_variable_find_in_environment"]
+  end
+
+  def test_live_usages
+    template = Template.parse(%({{test}}))
+    assert_equal 'worked', template.render!('test' => 'worked')
+    assert_equal 'worked wonderfully', template.render!('test' => 'worked wonderfully')
+    assert_equal true, Usage.results["Usage is enabled"]
+  end
+end

test/integration/usages/try_variables.rb

@@ -0,0 +1,23 @@
+module Liquid
+  class Context
+    remove_method :try_variable_find_in_environments
+    def try_variable_find_in_environments(key, raise_on_not_found:)
+      Usage.track("Using try_variable_find_in_environment")
+      @environments.each do |environment|
+        found_variable = lookup_and_evaluate(environment, key, raise_on_not_found: raise_on_not_found)
+        if !found_variable.nil? || @strict_variables && raise_on_not_found
+          return found_variable
+        end
+        Usage.track("try_variable_find_in_environment reports Nil but responds to key") if environment.key?(key)
+      end
+      @static_environments.each do |environment|
+        found_variable = lookup_and_evaluate(environment, key, raise_on_not_found: raise_on_not_found)
+        if !found_variable.nil? || @strict_variables && raise_on_not_found
+          return found_variable
+        end
+        Usage.track("try_variable_find_in_environment reports Nil but responds to key") if environment.key?(key)
+      end
+      nil
+    end
+  end
+end