Fix regex in CodeQL TextMate grammar that was silently failing

extensions/ql-vscode/CHANGELOG.md

@@ -3,6 +3,7 @@
 ## [UNRELEASED]
 
 - Remove support for CodeQL CLI versions older than 2.18.4. [#3895](https://github.com/github/vscode-codeql/pull/3895)
+- Fix regex in CodeQL TextMate grammar that was silently failing. [#3903](https://github.com/github/vscode-codeql/pull/3903)
 
 ## 1.7.0 - 20 December 2024
 

extensions/ql-vscode/syntaxes/ql.tmLanguage.yml

@@ -1065,7 +1065,7 @@ repository:
     beginPattern: '#as'
     # Ends after the first identifier we encounter.
     # REVIEW: Make similar to import-as-clause.
-    end: '(?<=(?#id-character)(?#end-of-id))'
+    end: '(?<=(?#id-character))(?#end-of-id)'
     match: meta.block.select-as-clause.ql
     patterns:
     - include: '#non-context-sensitive'

syntaxes/ql.tmLanguage.json

@@ -1469,7 +1469,7 @@
       }
     },
     "select-as-clause": {
-      "end": "(?x)(?<=(?:[0-9A-Za-z_])(?:(?!(?:[0-9A-Za-z_]))))",
+      "end": "(?x)(?<=(?:[0-9A-Za-z_]))(?:(?!(?:[0-9A-Za-z_])))",
       "match": "(?x)meta.block.select-as-clause.ql",
       "patterns": [
         {