JS: Remove parenthesized expressions from AST

javascript/downgrades/49e6663bb7d470c5f0e8e4bcef0ac01a8fb1a30a/upgrade.properties

@@ -0,0 +1,4 @@
+description: Remove parenthesized expression from AST, add has_parentheses relation
+compatibility: partial
+
+has_parentheses.rel: delete

javascript/extractor/src/com/semmle/js/extractor/ASTExtractor.java

@@ -1473,9 +1473,18 @@ public Label visit(SequenceExpression nd, Context c) {
 
     @Override
     public Label visit(ParenthesizedExpression nd, Context c) {
-      Label key = super.visit(nd, c);
-      visit(nd.getExpression(), key, 0, IdContext.VAR_BIND);
-      return key;
+      // Bypass the parenthesized expression node: visit the inner expression
+      // with the parent's context so it takes the place of the ParExpr in the tree.
+      // Count nested parentheses so that ((x)) results in depth 2.
+      int depth = 1;
+      Expression inner = nd.getExpression();
+      while (inner instanceof ParenthesizedExpression) {
+        depth++;
+        inner = ((ParenthesizedExpression) inner).getExpression();
+      }
+      Label innerLabel = inner.accept(this, c);
+      trapwriter.addTuple("has_parentheses", innerLabel, depth);
+      return innerLabel;
     }
 
     @Override

javascript/extractor/src/com/semmle/js/extractor/CFGExtractor.java

@@ -537,6 +537,11 @@ public Node visit(XMLDotDotExpression nd, Void c) {
       return nd.getLeft().accept(this, c);
     }
 
+    @Override
+    public Node visit(ParenthesizedExpression nd, Void c) {
+      return nd.getExpression().accept(this, c);
+    }
+
     public static Node of(Node nd) {
       return nd.accept(new First(), null);
     }
@@ -1299,7 +1304,7 @@ public Void visit(ExpressionStatement nd, SuccessorInfo i) {
 
     @Override
     public Void visit(ParenthesizedExpression nd, SuccessorInfo i) {
-      writeSuccessor(nd, First.of(nd.getExpression()));
+      // Bypass parenthesized expression - it has no DB entry, so just delegate to the inner expression
       return nd.getExpression().accept(this, i);
     }
 

javascript/extractor/tests/cfg/output/trap/ternary.js.trap

@@ -96,125 +96,118 @@ hasLocation(#20032,#20033)
 enclosing_stmt(#20032,#20031)
 expr_containers(#20032,#20001)
 #20034=*
-exprs(#20034,63,#20032,0,"(a ? b || c : d)")
-#20035=@"loc,{#10000},1,1,1,16"
-locations_default(#20035,#10000,1,1,1,16)
+exprs(#20034,11,#20032,0,"a ? b || c : d")
+#20035=@"loc,{#10000},1,2,1,15"
+locations_default(#20035,#10000,1,2,1,15)
 hasLocation(#20034,#20035)
 enclosing_stmt(#20034,#20031)
 expr_containers(#20034,#20001)
 #20036=*
-exprs(#20036,11,#20034,0,"a ? b || c : d")
-#20037=@"loc,{#10000},1,2,1,15"
-locations_default(#20037,#10000,1,2,1,15)
-hasLocation(#20036,#20037)
+exprs(#20036,79,#20034,0,"a")
+hasLocation(#20036,#20007)
 enclosing_stmt(#20036,#20031)
 expr_containers(#20036,#20001)
+literals("a","a",#20036)
+#20037=@"var;{a};{#20000}"
+variables(#20037,"a",#20000)
+bind(#20036,#20037)
 #20038=*
-exprs(#20038,79,#20036,0,"a")
-hasLocation(#20038,#20007)
+exprs(#20038,45,#20034,1,"b || c")
+#20039=@"loc,{#10000},1,6,1,11"
+locations_default(#20039,#10000,1,6,1,11)
+hasLocation(#20038,#20039)
 enclosing_stmt(#20038,#20031)
 expr_containers(#20038,#20001)
-literals("a","a",#20038)
-#20039=@"var;{a};{#20000}"
-variables(#20039,"a",#20000)
-bind(#20038,#20039)
 #20040=*
-exprs(#20040,45,#20036,1,"b || c")
-#20041=@"loc,{#10000},1,6,1,11"
-locations_default(#20041,#10000,1,6,1,11)
-hasLocation(#20040,#20041)
+exprs(#20040,79,#20038,0,"b")
+hasLocation(#20040,#20011)
 enclosing_stmt(#20040,#20031)
 expr_containers(#20040,#20001)
+literals("b","b",#20040)
+#20041=@"var;{b};{#20000}"
+variables(#20041,"b",#20000)
+bind(#20040,#20041)
 #20042=*
-exprs(#20042,79,#20040,0,"b")
-hasLocation(#20042,#20011)
+exprs(#20042,79,#20038,1,"c")
+hasLocation(#20042,#20015)
 enclosing_stmt(#20042,#20031)
 expr_containers(#20042,#20001)
-literals("b","b",#20042)
-#20043=@"var;{b};{#20000}"
-variables(#20043,"b",#20000)
+literals("c","c",#20042)
+#20043=@"var;{c};{#20000}"
+variables(#20043,"c",#20000)
 bind(#20042,#20043)
 #20044=*
-exprs(#20044,79,#20040,1,"c")
-hasLocation(#20044,#20015)
+exprs(#20044,79,#20034,2,"d")
+hasLocation(#20044,#20019)
 enclosing_stmt(#20044,#20031)
 expr_containers(#20044,#20001)
-literals("c","c",#20044)
-#20045=@"var;{c};{#20000}"
-variables(#20045,"c",#20000)
+literals("d","d",#20044)
+#20045=@"var;{d};{#20000}"
+variables(#20045,"d",#20000)
 bind(#20044,#20045)
+has_parentheses(#20034,1)
 #20046=*
-exprs(#20046,79,#20036,2,"d")
-hasLocation(#20046,#20019)
+exprs(#20046,79,#20032,1,"e")
+hasLocation(#20046,#20025)
 enclosing_stmt(#20046,#20031)
 expr_containers(#20046,#20001)
-literals("d","d",#20046)
-#20047=@"var;{d};{#20000}"
-variables(#20047,"d",#20000)
+literals("e","e",#20046)
+#20047=@"var;{e};{#20000}"
+variables(#20047,"e",#20000)
 bind(#20046,#20047)
 #20048=*
-exprs(#20048,79,#20032,1,"e")
-hasLocation(#20048,#20025)
-enclosing_stmt(#20048,#20031)
-expr_containers(#20048,#20001)
-literals("e","e",#20048)
-#20049=@"var;{e};{#20000}"
-variables(#20049,"e",#20000)
-bind(#20048,#20049)
+entry_cfg_node(#20048,#20001)
+#20049=@"loc,{#10000},1,1,1,0"
+locations_default(#20049,#10000,1,1,1,0)
+hasLocation(#20048,#20049)
 #20050=*
-entry_cfg_node(#20050,#20001)
-#20051=@"loc,{#10000},1,1,1,0"
-locations_default(#20051,#10000,1,1,1,0)
-hasLocation(#20050,#20051)
-#20052=*
-exit_cfg_node(#20052,#20001)
-hasLocation(#20052,#20029)
+exit_cfg_node(#20050,#20001)
+hasLocation(#20050,#20029)
 successor(#20031,#20032)
 successor(#20032,#20034)
 successor(#20034,#20036)
-successor(#20036,#20038)
+#20051=*
+guard_node(#20051,1,#20036)
+hasLocation(#20051,#20007)
+successor(#20051,#20038)
+#20052=*
+guard_node(#20052,0,#20036)
+hasLocation(#20052,#20007)
+successor(#20052,#20044)
+successor(#20036,#20051)
+successor(#20036,#20052)
+successor(#20038,#20040)
 #20053=*
-guard_node(#20053,1,#20038)
-hasLocation(#20053,#20007)
-successor(#20053,#20040)
+guard_node(#20053,1,#20040)
+hasLocation(#20053,#20011)
+successor(#20053,#20050)
 #20054=*
-guard_node(#20054,0,#20038)
-hasLocation(#20054,#20007)
-successor(#20054,#20046)
-successor(#20038,#20053)
-successor(#20038,#20054)
-successor(#20040,#20042)
+guard_node(#20054,0,#20040)
+hasLocation(#20054,#20011)
+successor(#20054,#20042)
+successor(#20040,#20053)
+successor(#20040,#20054)
 #20055=*
 guard_node(#20055,1,#20042)
-hasLocation(#20055,#20011)
-successor(#20055,#20052)
+hasLocation(#20055,#20015)
+successor(#20055,#20050)
 #20056=*
 guard_node(#20056,0,#20042)
-hasLocation(#20056,#20011)
-successor(#20056,#20044)
+hasLocation(#20056,#20015)
+successor(#20056,#20046)
 successor(#20042,#20055)
 successor(#20042,#20056)
 #20057=*
 guard_node(#20057,1,#20044)
-hasLocation(#20057,#20015)
-successor(#20057,#20052)
+hasLocation(#20057,#20019)
+successor(#20057,#20050)
 #20058=*
 guard_node(#20058,0,#20044)
-hasLocation(#20058,#20015)
-successor(#20058,#20048)
+hasLocation(#20058,#20019)
+successor(#20058,#20046)
 successor(#20044,#20057)
 successor(#20044,#20058)
-#20059=*
-guard_node(#20059,1,#20046)
-hasLocation(#20059,#20019)
-successor(#20059,#20052)
-#20060=*
-guard_node(#20060,0,#20046)
-hasLocation(#20060,#20019)
-successor(#20060,#20048)
-successor(#20046,#20059)
-successor(#20046,#20060)
-successor(#20048,#20052)
-successor(#20050,#20031)
+successor(#20046,#20050)
+successor(#20048,#20031)
 numlines(#10000,1,1,0)
 filetype(#10000,"javascript")