fix: issue with escaped placeholder at end of tag (#143)

Author: DylanPiercey

.changeset/afraid-monkeys-walk.md

@@ -0,0 +1,5 @@
+---
+"htmljs-parser": patch
+---
+
+Fix issue where and extra character was being consumed if an escaped placeholder was at the end of a tag.

src/__tests__/fixtures/placeholder-backslash/__snapshots__/placeholder-backslash.expected.txt

@@ -67,4 +67,14 @@
   │  │ │╰─ closeTagEnd(d)
   │  │ ╰─ closeTagName
   │  ├─ text "\n"
-  ╰─ ╰─ closeTagStart "</"
+  ╰─ ╰─ closeTagStart "</"
+16├─ 
+17╭─ <e>\${</e>
+  │  │││ │ │ │╰─ closeTagEnd(e)
+  │  │││ │ │ ╰─ closeTagName
+  │  │││ │ ╰─ closeTagStart "</"
+  │  │││ ╰─ text "${"
+  │  ││╰─ openTagEnd
+  │  │╰─ tagName
+  ╰─ ╰─ openTagStart
+18╰─ 

src/__tests__/fixtures/placeholder-backslash/input.marko

@@ -12,4 +12,6 @@
 </c>
 <d>
     \\$!{test}
-</d>
+</d>
+
+<e>\${</e>

src/states/PLACEHOLDER.ts

@@ -73,6 +73,8 @@ export function checkForPlaceholder(parser: Parser, code: number) {
     }
 
     if (curCode === CODE.OPEN_CURLY_BRACE) {
+      parser.forward = 0;
+
       if (ahead) {
         const remainder = ahead % 2;
         const extra = (ahead + remainder) / 2; // Number of backslashes to omit from output.
@@ -94,7 +96,6 @@ export function checkForPlaceholder(parser: Parser, code: number) {
       parser.endText();
       parser.enterState(PLACEHOLDER).escape = escape;
       parser.pos += escape ? 2 : 3; // skip ${ or $!{
-      parser.forward = 0;
       parser.enterState(STATE.EXPRESSION).shouldTerminate =
         matchesCloseCurlyBrace;
       return true;