Python: re, handle \Z

Author: yoff

python/ql/src/semmle/python/regex.qll

@@ -624,7 +624,8 @@ abstract class RegexString extends Expr {
         exists(int y | this.lastPart(start, y) |
             this.emptyMatchAtEndGroup(end, y) or
             this.qualifiedItem(end, y, true) or
-            this.specialCharacter(end, y, "$")
+            this.specialCharacter(end, y, "$") or
+            y = end+2 and this.escapingChar(end) and this.getChar(end+1) = "Z"
         )
         or
         exists(int x |

python/ql/test/query-tests/Expressions/Regex/DuplicateCharacterInSet.expected

@@ -1,3 +1,3 @@
-| test.py:44:12:44:18 | Str | This regular expression includes duplicate character 'A' in a set of characters. |
-| test.py:45:12:45:19 | Str | This regular expression includes duplicate character '0' in a set of characters. |
-| test.py:46:12:46:21 | Str | This regular expression includes duplicate character '-' in a set of characters. |
+| test.py:45:12:45:18 | Str | This regular expression includes duplicate character 'A' in a set of characters. |
+| test.py:46:12:46:19 | Str | This regular expression includes duplicate character '0' in a set of characters. |
+| test.py:47:12:47:21 | Str | This regular expression includes duplicate character '-' in a set of characters. |

python/ql/test/query-tests/Expressions/Regex/UnmatchableCaret.expected

@@ -1,4 +1,4 @@
 | test.py:4:12:4:19 | Str | This regular expression includes an unmatchable caret at offset 1. |
 | test.py:5:12:5:23 | Str | This regular expression includes an unmatchable caret at offset 5. |
 | test.py:6:12:6:21 | Str | This regular expression includes an unmatchable caret at offset 2. |
-| test.py:77:12:77:27 | Str | This regular expression includes an unmatchable caret at offset 8. |
+| test.py:78:12:78:27 | Str | This regular expression includes an unmatchable caret at offset 8. |

python/ql/test/query-tests/Expressions/Regex/UnmatchableDollar.expected

@@ -1,8 +1,4 @@
 | test.py:29:12:29:19 | Str | This regular expression includes an unmatchable dollar at offset 3. |
 | test.py:30:12:30:23 | Str | This regular expression includes an unmatchable dollar at offset 3. |
 | test.py:31:12:31:20 | Str | This regular expression includes an unmatchable dollar at offset 2. |
-| test.py:41:10:41:27 | Str | This regular expression includes an unmatchable dollar at offset 5. |
-| test.py:41:10:41:27 | Str | This regular expression includes an unmatchable dollar at offset 11. |
-| test.py:41:10:41:27 | Str | This regular expression includes an unmatchable dollar at offset 13. |
-| test.py:42:10:42:25 | Str | This regular expression includes an unmatchable dollar at offset 3. |
 | test.py:79:12:79:26 | Str | This regular expression includes an unmatchable dollar at offset 3. |