JS: Simplify charpred of Match

asger-semmle · asger-semmle · commit 4680e3a89a4d · 2019-11-15T09:27:20.000Z
diff --git a/javascript/ql/src/Performance/ReDoS.ql b/javascript/ql/src/Performance/ReDoS.ql
@@ -269,7 +269,7 @@ newtype TState =
     (
       i = 0
       or
-      i = [ 1 .. t.(RegExpConstant).getValue().length() - 1 ]
+      exists(t.(RegExpConstant).getValue().charAt(i))
     )
   } or
   Accept(RegExpRoot l) { l.isRelevant() }

Original file line number	Diff line number	Diff line change
`@@ -269,7 +269,7 @@ newtype TState =`
`269`	`269`	`(`
`270`	`270`	`i = 0`
`271`	`271`	`or`
`272`		`- i = [ 1 .. t.(RegExpConstant).getValue().length() - 1 ]`
	`272`	`+ exists(t.(RegExpConstant).getValue().charAt(i))`
`273`	`273`	`)`
`274`	`274`	`} or`
`275`	`275`	`Accept(RegExpRoot l) { l.isRelevant() }`