From 48afa46adc4703302959a5adc93dbbfd27c78168 Mon Sep 17 00:00:00 2001
From: Ben Ashton <ben@n0m.org>
Date: Sun, 25 Sep 2022 16:48:14 -0600
Subject: [PATCH] Improved handling of escape sequences

---
 src/token_stream.mjs | 21 +++++++++++++++++++--
 1 file changed, 19 insertions(+), 2 deletions(-)

diff --git a/src/token_stream.mjs b/src/token_stream.mjs
index 3c835ad..6a150e1 100644
--- a/src/token_stream.mjs
+++ b/src/token_stream.mjs
@@ -65,7 +65,16 @@ export class TokenStream {
         // Skip shebang (can be used to execute templates directly with an
         // interpreter that first builds the template and then executes)
         this._skipShebang();
-      } else if (this._cs.isNext(TokenStream.ESCAPE)) {
+      } else if (this._isNextEscapedTag([
+        // Allow escaping of open and full-line tags
+        TokenStream.OPEN_STATEMENT,
+        TokenStream.OPEN_INLINE,
+        TokenStream.OPEN_INLINE_UNESCAPED,
+        TokenStream.OPEN_INLINE_STATEMENT,
+        TokenStream.OPEN_INLINE_STATEMENT_UNESCAPED,
+        TokenStream.STATEMENT,
+        TokenStream.COMMENT
+      ])) {
         // Skip escape
         this._cs.next(TokenStream.ESCAPE.length);
         // Treat everything as raw until next space
@@ -132,7 +141,7 @@ export class TokenStream {
     let value = '';
     while (!this._cs.eof() && !this._cs.isNext(closeTag)) {
       // Handle any escaped closing tag
-      if (this._cs.isNext(TokenStream.ESCAPE)) {
+      if (this._isNextEscapedTag([closeTag])) {
         // Skip escape
         this._cs.next(TokenStream.ESCAPE.length);
 
@@ -243,4 +252,12 @@ export class TokenStream {
   _isSpace(c) {
     return /[^\S\r\n]/.test(c);
   }
+
+  _isNextEscapedTag(possibleTags=[]) {
+    if (!this._cs.isNext(TokenStream.ESCAPE)) return false;
+
+    return !!possibleTags.find(tag =>
+      this._cs.isNext(TokenStream.ESCAPE + tag)
+    );
+  }
 }