Use difftastic

lib/quickdraw.rb

@@ -1,5 +1,7 @@
 # frozen_string_literal: true
 
+require "difftastic"
+
 module Quickdraw
 	autoload :ArgumentError, "quickdraw/errors/argument_error"
 	autoload :Assertions, "quickdraw/assertions"

lib/quickdraw/assertions.rb

@@ -1,17 +1,40 @@
 # frozen_string_literal: true
 
 module Quickdraw::Assertions
+	DIFFER = Difftastic::Differ.new(
+		color: :always,
+		tab_width: 2,
+	)
+
 	def assert_equal(actual, expected)
 		assert(actual == expected) do
-			<<~MESSAGE
-				\e[34mExpected:\e[0m
+			diff = DIFFER.diff_objects(actual, expected)
 
-				#{actual.inspect}
+			"Expected objects to be equal (compared with `==`):\n\n#{diff}"
+		end
+	end
 
-				\e[34mto be == to:\e[0m
+	def assert_equal_sql(actual, expected)
+		unless String === actual && String === expected
+			raise ArgumentError.new("expected both actual and expected to be strings")
+		end
 
-				#{expected.inspect}
-			MESSAGE
+		assert(actual == expected) do
+			diff = DIFFER.diff_sql(actual, expected)
+
+			"Expected SQL strings to be equal (compared with `==`):\n\n#{diff}"
+		end
+	end
+
+	def assert_equal_html(actual, expected)
+		unless String === actual && String === expected
+			raise ArgumentError.new("expected both actual and expected to be strings")
+		end
+
+		assert(actual == expected) do
+			diff = DIFFER.diff_html(actual, expected)
+
+			"Expected HTML strings to be equal (compared with `==`):\n\n#{diff}"
 		end
 	end
 

lib/quickdraw/test.rb

@@ -4,7 +4,7 @@ class Quickdraw::Test
 	include Quickdraw::Assertions
 
 	def self.test(description = nil, skip: false, &block)
-		$quickdraw_runner << [self, description, skip, block]
+		$quickdraw_runner << [self, description, skip, block].freeze
 	end
 
 	def initialize(description:, skip:, block:)

quickdraw.gemspec

@@ -35,4 +35,5 @@ Gem::Specification.new do |spec|
 	spec.metadata["rubygems_mfa_required"] = "true"
 
 	spec.add_dependency "io-watch", "~> 0.6"
+	spec.add_dependency "difftastic", "~> 0.1"
 end