new failing tests for char escaping

lib/ymlr/encoder_test.exs

@@ -72,8 +72,9 @@ defmodule Ymlr.EncoderTest do
     end
 
     test "quoted strings - escape seq forces double quotes (tab char)" do
-      assert MUT.to_s!("a\tb") == ~s("a\tb")
-      assert MUT.to_s!("!a\tb") == ~s("!a\tb")
+      assert MUT.to_s!("a\tb") == ~S("a\tb")
+      assert MUT.to_s!("!a\tb") == ~S("!a\tb")
+      assert MUT.to_s!("a\tb\nc") == ~s("a\\tb\nc")
     end
 
     test "quoted strings - listy and mappy things" do
@@ -84,7 +85,18 @@ defmodule Ymlr.EncoderTest do
       assert MUT.to_s!("{}") == ~S('{}')
       assert MUT.to_s!("[{}]") == ~S('[{}]')
       # ... (use double quotes if string contains single quotes)
-      assert MUT.to_s!(~S(["I don't know!\nRea|\y?"])) == ~S("[\"I don't know!\\nRea|\\y?\"]")
+      assert MUT.to_s!(~S(["I don't know!\nRea|\y?"])) == ~S("[\"I don't know!\nRea|\\y?\"]")
+    end
+
+    test "quoted strings - handling backslashes" do
+      # double quotes because of single quote
+      assert MUT.to_s!(~s(a'bc\\w)) == ~S("a'bc\\w")
+      # double quotes because of tab
+      assert MUT.to_s!(~s(a\tbc\\w)) == ~S("a\tbc\\w")
+      # double quotes because of tab but with newline
+      assert MUT.to_s!(~s(a\tb\nc\\w)) == ~s("a\\tb\nc\\\\w")
+      # no double quotes
+      assert MUT.to_s!(~S(a\b)) == ~S(a\b)
     end
 
     test "quoted strings - in map key" do