Add Julia (exercism#21)

* Add Julia

* Fix alignment

* Fix tests

Co-authored-by: Jeremy Walker <[email protected]>

Author: SaschaMann

lib/languages/julia.txt

@@ -0,0 +1 @@
+#

test/languages/julia_test.rb

@@ -0,0 +1,87 @@
+require "test_helper"
+
+module SnippetExtractor
+  module Languages
+    class JuliaTest < Minitest::Test
+      def test_long_example
+        code = <<~CODE
+          # Types
+          abstract type Pet end
+
+          struct Dog <: Pet
+              name::AbstractString
+          end
+
+          struct Cat <: Pet
+              name::AbstractString
+          end
+
+          """
+              encounter(a, b)
+
+          Simulate an encounter between `a` and `b`.
+          """
+          encounter(a, b) = "$(name(a)) meets $(name(b)) and $(meets(a, b))."
+
+          """
+
+        CODE
+
+        expected = <<~CODE
+          abstract type Pet end
+
+          struct Dog <: Pet
+              name::AbstractString
+          end
+
+          struct Cat <: Pet
+              name::AbstractString
+          end
+
+        CODE
+
+        assert_equal expected, ExtractSnippet.(code, :julia)
+      end
+
+      def test_short_example
+        code = <<~CODE
+          """
+              preptime(layers)
+
+          Return the preparation time in minutes.
+          """
+          preptime(layers) = 2 * layers
+
+          """
+              remaining_time(current_time)
+
+          Return the remaining oven time in minutes.
+          """
+          remaining_time(current_time) = 60 - current_time
+
+          """
+              total_working_time(layers, current_time)
+
+          Return the total working time in minutes.
+          """
+          total_working_time(layers, current_time) = preptime(layers) + current_time
+        CODE
+
+        expected = <<~CODE
+          """
+              preptime(layers)
+
+          Return the preparation time in minutes.
+          """
+          preptime(layers) = 2 * layers
+
+          """
+              remaining_time(current_time)
+
+        CODE
+
+        assert_equal expected, ExtractSnippet.(code, :julia)
+      end
+    end
+  end
+end