Avoid excessive backtracking when parsing unterminated strings

1 files changed, 20 insertions, 0 deletions

diff --git a/test/styles/parser/tokeniser.tests.js b/test/styles/parser/tokeniser.tests.js
index 16f3847..04c25e0 100644
--- a/test/styles/parser/tokeniser.tests.js
+++ b/test/styles/parser/tokeniser.tests.js
@@ -31,10 +31,30 @@ test("strings are tokenised", function() {
     assertTokens("'Tristan'", [isToken("string", "Tristan")]);
 });
 
+test("escaped string terminators in strings are tokenised", function() {
+    assertTokens("'Tristan\\''", [isToken("string", "Tristan\\'")]);
+});
+
+test("escape sequences in strings are tokenised", function() {
+    assertTokens("'Tristan\\\\'", [isToken("string", "Tristan\\\\")]);
+});
+
 test("unterminated strings are tokenised", function() {
     assertTokens("'Tristan", [isToken("unterminated-string", "Tristan")]);
 });
 
+test("unterminated strings ending with escaped string terminator are tokenised", function() {
+    assertTokens("'Tristan\\'", [isToken("unterminated-string", "Tristan\\'")]);
+});
+
+test("unterminated strings with unterminated escape are tokenised", function() {
+    assertTokens("'Tristan\\", [isToken("unterminated-string", "Tristan\\")]);
+});
+
+test("unterminated strings with many escape sequences do not cause excessive backtracking", function() {
+    assertTokens("'" + "\\a".repeat(50), [isToken("unterminated-string", "\\a".repeat(50))]);
+});
+
 test("arrows are tokenised", function() {
     assertTokens("=>", [isToken("arrow")]);
 });