Merge pull request github#13009 from MathiasVP/fix-tostring-on-regex-literals

Swift: Fix TODO on regex literals's `toString`

Author: MathiasVP

swift/integration-tests/linux-only/RegexLiteralExpr/RegexLiteralExpr.expected

@@ -1,2 +1,2 @@
-| regex.swift:1:5:1:5 | ... | getType: | Regex<Substring> | getPattern: | a.*a | getVersion: | 1 |
-| regex.swift:2:5:2:5 | ... | getType: | Regex<(Substring, Substring)> | getPattern: | the number (\\d+) | getVersion: | 1 |
+| regex.swift:1:5:1:5 | a.*a | getType: | Regex<Substring> | getPattern: | a.*a | getVersion: | 1 |
+| regex.swift:2:5:2:5 | the number (\\d+) | getType: | Regex<(Substring, Substring)> | getPattern: | the number (\\d+) | getVersion: | 1 |

swift/ql/lib/codeql/swift/elements/expr/RegexLiteralExpr.qll

@@ -1,7 +1,5 @@
 private import codeql.swift.generated.expr.RegexLiteralExpr
 
 class RegexLiteralExpr extends Generated::RegexLiteralExpr {
-  override string toString() {
-    result = "..." // TODO: We can improve this once we extract the regex
-  }
+  override string toString() { result = this.getPattern() }
 }