Swift: Improve RegexEvals.ql and summary regex reporting.

Author: geoffw0

swift/ql/src/queries/Summary/RegexEvals.ql

@@ -10,6 +10,11 @@
 import swift
 import codeql.swift.regex.Regex
 
-from RegexEval e
-select e,
-  "Regular expression evaluation with " + count(e.getARegex()).toString() + " associated regex(s)."
+from RegexEval e, string message, Expr regex
+where
+  message = "Regular expression evaluation with source $@." and regex = e.getARegex()
+  or
+  message = "Regular expression evaluation with no identified source." and
+  not exists(e.getARegex()) and
+  regex = e
+select e, message, regex, regex.toString()

swift/ql/src/queries/Summary/SummaryStats.ql

@@ -30,8 +30,8 @@ predicate statistic(string what, string value) {
   or
   what = "Regular expression evals" and value = count(RegexEval e).toString()
   or
-  what = "Regular expression evals with associated regex" and
-  value = count(RegexEval e | exists(e.getARegex())).toString()
+  what = "Regular expressions evaluated" and
+  value = count(RegexEval e | | e.getARegex()).toString()
 }
 
 from string what, string value