Rust: Handle string literals with line breaks

Author: paldepind

rust/ql/lib/codeql/rust/elements/internal/LiteralExprImpl.qll

@@ -68,7 +68,7 @@ module Impl {
    * [1]: https://doc.rust-lang.org/reference/tokens.html#string-literals
    */
   class StringLiteralExpr extends LiteralExpr {
-    StringLiteralExpr() { this.getTextValue().regexpMatch("r?#*\".*\"#*") }
+    StringLiteralExpr() { this.getTextValue().charAt(0) = ["\"", "r"] }
 
     override string getAPrimaryQlClass() { result = "StringLiteralExpr" }
   }

rust/ql/test/extractor-tests/literal/literal.expected

@@ -16,6 +16,8 @@ stringLiteral
 | literal.rs:21:5:21:8 | r"R" |
 | literal.rs:22:5:22:11 | "\\\\x52" |
 | literal.rs:23:5:23:11 | r"\\x52" |
+| literal.rs:25:5:29:5 | "\n    A normal string literal\n... |
+| literal.rs:31:5:34:6 | r#"\n    A raw string literal\n ... |
 integerLiteral
 | literal.rs:39:5:39:7 | 123 |  |
 | literal.rs:40:5:40:10 | 123i32 | i32 |