Unused local query: exclude mandatory declarations

Author: smowton

java/ql/src/Violations of Best Practice/Dead Code/UnusedLocal.ql

@@ -11,22 +11,13 @@
 import java
 import DeadLocals
 
-predicate exceptionVariable(LocalVariableDeclExpr ve) {
-  exists(CatchClause catch | catch.getVariable() = ve)
-}
-
-predicate enhancedForVariable(LocalVariableDeclExpr ve) {
-  exists(EnhancedForStmt for | for.getVariable() = ve)
-}
-
 from LocalVariableDeclExpr ve, LocalVariableDecl v
 where
   v = ve.getVariable() and
   not assigned(v) and
   not read(v) and
   (not exists(ve.getInit()) or exprHasNoEffect(ve.getInit())) and
-  // Remove contexts where Java forces a variable declaration: enhanced-for and catch clauses.
+  // Remove contexts where Java forces a variable declaration: enhanced-for, catch clauses and pattern cases.
   // Rules about catch clauses belong in an exception handling query
-  not exceptionVariable(ve) and
-  not enhancedForVariable(ve)
+  not ve.hasImplicitInit()
 select v, "Variable " + v.getName() + " is not used."