get ReDoSUtil in sync for ruby

python/ql/lib/semmle/python/security/performance/ReDoSUtil.qll

@@ -218,7 +218,7 @@ private newtype TInputSymbol =
       recc instanceof RegExpCharacterClass and
       not recc.(RegExpCharacterClass).isUniversalClass()
       or
-      recc instanceof RegExpCharacterClassEscape
+      isEscapeClass(recc, _)
     )
   } or
   /** An input symbol representing all characters matched by `.`. */
@@ -340,13 +340,13 @@ private module CharacterClasses {
         char <= hi
       )
       or
-      exists(RegExpCharacterClassEscape escape | escape = child |
-        escape.getValue() = escape.getValue().toLowerCase() and
-        classEscapeMatches(escape.getValue(), char)
+      exists(string charClass | isEscapeClass(child, charClass) |
+        charClass.toLowerCase() = charClass and
+        classEscapeMatches(charClass, char)
         or
         char = getARelevantChar() and
-        escape.getValue() = escape.getValue().toUpperCase() and
-        not classEscapeMatches(escape.getValue().toLowerCase(), char)
+        charClass.toUpperCase() = charClass and
+        not classEscapeMatches(charClass, char)
       )
     )
   }
@@ -409,10 +409,10 @@ private module CharacterClasses {
       or
       child.(RegExpCharacterRange).isRange(_, result)
       or
-      exists(RegExpCharacterClassEscape escape | child = escape |
-        result = min(string s | classEscapeMatches(escape.getValue().toLowerCase(), s))
+      exists(string charClass | isEscapeClass(child, charClass) |
+        result = min(string s | classEscapeMatches(charClass.toLowerCase(), s))
         or
-        result = max(string s | classEscapeMatches(escape.getValue().toLowerCase(), s))
+        result = max(string s | classEscapeMatches(charClass.toLowerCase(), s))
       )
     )
   }
@@ -466,33 +466,36 @@ private module CharacterClasses {
    * An implementation of `CharacterClass` for \d, \s, and \w.
    */
   private class PositiveCharacterClassEscape extends CharacterClass {
-    RegExpCharacterClassEscape cc;
+    RegExpTerm cc;
+    string charClass;
 
     PositiveCharacterClassEscape() {
-      this = getCanonicalCharClass(cc) and cc.getValue() = ["d", "s", "w"]
+      isEscapeClass(cc, charClass) and
+      this = getCanonicalCharClass(cc) and
+      charClass = ["d", "s", "w"]
     }
 
     override string getARelevantChar() {
-      cc.getValue() = "d" and
+      charClass = "d" and
       result = ["0", "9"]
       or
-      cc.getValue() = "s" and
+      charClass = "s" and
       result = " "
       or
-      cc.getValue() = "w" and
+      charClass = "w" and
       result = ["a", "Z", "_", "0", "9"]
     }
 
-    override predicate matches(string char) { classEscapeMatches(cc.getValue(), char) }
+    override predicate matches(string char) { classEscapeMatches(charClass, char) }
 
     override string choose() {
-      cc.getValue() = "d" and
+      charClass = "d" and
       result = "9"
       or
-      cc.getValue() = "s" and
+      charClass = "s" and
       result = " "
       or
-      cc.getValue() = "w" and
+      charClass = "w" and
       result = "a"
     }
   }
@@ -501,26 +504,29 @@ private module CharacterClasses {
    * An implementation of `CharacterClass` for \D, \S, and \W.
    */
   private class NegativeCharacterClassEscape extends CharacterClass {
-    RegExpCharacterClassEscape cc;
+    RegExpTerm cc;
+    string charClass;
 
     NegativeCharacterClassEscape() {
-      this = getCanonicalCharClass(cc) and cc.getValue() = ["D", "S", "W"]
+      isEscapeClass(cc, charClass) and
+      this = getCanonicalCharClass(cc) and
+      charClass = ["D", "S", "W"]
     }
 
     override string getARelevantChar() {
-      cc.getValue() = "D" and
+      charClass = "D" and
       result = ["a", "Z", "!"]
       or
-      cc.getValue() = "S" and
+      charClass = "S" and
       result = ["a", "9", "!"]
       or
-      cc.getValue() = "W" and
+      charClass = "W" and
       result = [" ", "!"]
     }
 
     bindingset[char]
     override predicate matches(string char) {
-      not classEscapeMatches(cc.getValue().toLowerCase(), char)
+      not classEscapeMatches(charClass.toLowerCase(), char)
     }
   }
 }
@@ -599,7 +605,7 @@ predicate delta(State q1, EdgeLabel lbl, State q2) {
     q2 = after(cc)
   )
   or
-  exists(RegExpCharacterClassEscape cc |
+  exists(RegExpTerm cc | isEscapeClass(cc, _) |
     q1 = before(cc) and
     lbl = CharClass(cc.getRawValue() + "|" + getCanonicalizationFlags(cc.getRootTerm())) and
     q2 = after(cc)

python/ql/lib/semmle/python/security/performance/RegExpTreeView.qll

@@ -5,6 +5,14 @@
 import python
 import semmle.python.RegexTreeView
 
+/**
+ * Holds if `term` is an ecape class representing e.g. `\d`.
+ * `clazz` is which character class it represents, e.g. "d" for `\d`.
+ */
+predicate isEscapeClass(RegExpTerm term, string clazz) {
+  exists(RegExpCharacterClassEscape escape | term = escape | escape.getValue() = clazz)
+}
+
 /**
  * Holds if the regular expression should not be considered.
  *