JS: make use of getUnderlyingValue in js/useless-assignment-to-local

Esben Sparre Andreasen · Esben Sparre Andreasen · commit 90c77134af36 · 2018-10-29T09:22:53.000+01:00
diff --git a/javascript/ql/src/Declarations/DeadStoreOfLocal.ql b/javascript/ql/src/Declarations/DeadStoreOfLocal.ql
@@ -38,9 +38,7 @@ predicate isDefaultInit(Expr e) {
   // initialising to an empty array or object literal, even if unnecessary,
   // can convey useful type information to the reader
   e.(ArrayExpr).getSize() = 0 or
-  e.(ObjectExpr).getNumProperty() = 0 or
-  // recursive case
-  isDefaultInit(e.(AssignExpr).getRhs())
+  e.(ObjectExpr).getNumProperty() = 0
 }
 
 from VarDef dead, PurelyLocalVariable v  // captured variables may be read by closures, so don't flag them
@@ -60,7 +58,7 @@ where deadStoreOfLocal(dead, v) and
       // don't flag overwrites with `null` or `undefined`
       not SyntacticConstants::isNullOrUndefined(dead.getSource()) and
       // don't flag default inits that are later overwritten
-      not (isDefaultInit(dead.getSource()) and dead.isOverwritten(v)) and
+      not (isDefaultInit(dead.getSource().(Expr).getUnderlyingValue()) and dead.isOverwritten(v)) and
       // don't flag assignments in externs
       not dead.(ASTNode).inExternsFile() and
       // don't flag exported variables
diff --git a/javascript/ql/test/query-tests/Declarations/DeadStoreOfLocal/DeadStoreOfLocal.expected b/javascript/ql/test/query-tests/Declarations/DeadStoreOfLocal/DeadStoreOfLocal.expected
@@ -7,4 +7,3 @@
 | tst.js:45:6:45:11 | x = 23 | This definition of x is useless, since its value is never read. |
 | tst.js:51:6:51:11 | x = 23 | This definition of x is useless, since its value is never read. |
 | tst.js:132:7:132:13 | {x} = o | This definition of x is useless, since its value is never read. |
-| tst.js:158:11:158:21 | a = (x, -1) | This definition of a is useless, since its value is never read. |
