Issue #1658 - Part 3: Implement support for optional chaining in JS reflection

Partially based on:
Bug 1610447 - Update Reflect to handle Optional Chaining operator
Bug 1657835 - Assertion failure: false, at js/src/builtin/ReflectParse.cpp:3168

2 files changed, 72 insertions, 17 deletions

diff --git a/js/src/builtin/ReflectParse.cpp b/js/src/builtin/ReflectParse.cpp
index 65bd16b270..7b230b07a0 100644
--- a/js/src/builtin/ReflectParse.cpp
+++ b/js/src/builtin/ReflectParse.cpp
@@ -576,10 +576,11 @@ class NodeBuilder
                                     MutableHandleValue dst);
 
     MOZ_MUST_USE bool callExpression(HandleValue callee, NodeVector& args, TokenPos* pos,
-                                     MutableHandleValue dst);
+                                     MutableHandleValue dst, bool isOptional = false);
 
     MOZ_MUST_USE bool memberExpression(bool computed, HandleValue expr, HandleValue member,
-                                       TokenPos* pos, MutableHandleValue dst);
+                                       TokenPos* pos, MutableHandleValue dst,
+                                       bool isOptional = false);
 
     MOZ_MUST_USE bool arrayExpression(NodeVector& elts, TokenPos* pos, MutableHandleValue dst);
 
@@ -593,6 +594,11 @@ class NodeBuilder
 
     MOZ_MUST_USE bool spreadExpression(HandleValue expr, TokenPos* pos, MutableHandleValue dst);
 
+    MOZ_MUST_USE bool optionalExpression(HandleValue expr, TokenPos* pos, MutableHandleValue dst);
+
+    MOZ_MUST_USE bool deleteOptionalExpression(HandleValue expr, TokenPos* pos,
+                                               MutableHandleValue dst);
+
     MOZ_MUST_USE bool computedName(HandleValue name, TokenPos* pos, MutableHandleValue dst);
 
     MOZ_MUST_USE bool objectExpression(NodeVector& elts, TokenPos* pos, MutableHandleValue dst);
@@ -1121,7 +1127,7 @@ NodeBuilder::sequenceExpression(NodeVector& elts, TokenPos* pos, MutableHandleVa
 
 bool
 NodeBuilder::callExpression(HandleValue callee, NodeVector& args, TokenPos* pos,
-                            MutableHandleValue dst)
+                            MutableHandleValue dst, bool isOptional)
 {
     RootedValue array(cx);
     if (!newArray(args, &array))
@@ -1131,9 +1137,12 @@ NodeBuilder::callExpression(HandleValue callee, NodeVector& args, TokenPos* pos,
     if (!cb.isNull())
         return callback(cb, callee, array, pos, dst);
 
-    return newNode(AST_CALL_EXPR, pos,
-                   "callee", callee,
-                   "arguments", array,
+    return newNode(isOptional ? AST_OPT_CALL_EXPR : AST_CALL_EXPR,
+                   pos,
+                   "callee",
+                   callee,
+                   "arguments",
+                   array,
                    dst);
 }
 
@@ -1157,7 +1166,7 @@ NodeBuilder::newExpression(HandleValue callee, NodeVector& args, TokenPos* pos,
 
 bool
 NodeBuilder::memberExpression(bool computed, HandleValue expr, HandleValue member, TokenPos* pos,
-                              MutableHandleValue dst)
+                              MutableHandleValue dst, bool isOptional)
 {
     RootedValue computedVal(cx, BooleanValue(computed));
 
@@ -1165,10 +1174,14 @@ NodeBuilder::memberExpression(bool computed, HandleValue expr, HandleValue membe
     if (!cb.isNull())
         return callback(cb, computedVal, expr, member, pos, dst);
 
-    return newNode(AST_MEMBER_EXPR, pos,
-                   "object", expr,
-                   "property", member,
-                   "computed", computedVal,
+    return newNode(isOptional ? AST_OPT_MEMBER_EXPR : AST_MEMBER_EXPR,
+                   pos,
+                   "object",
+                   expr,
+                   "property",
+                   member,
+                   "computed",
+                   computedVal,
                    dst);
 }
 
@@ -1232,6 +1245,22 @@ NodeBuilder::spreadExpression(HandleValue expr, TokenPos* pos, MutableHandleValu
 }
 
 bool
+NodeBuilder::optionalExpression(HandleValue expr, TokenPos* pos, MutableHandleValue dst)
+{
+  return newNode(AST_OPTIONAL_EXPR, pos,
+                 "expression", expr,
+                 dst);
+}
+
+bool
+NodeBuilder::deleteOptionalExpression(HandleValue expr, TokenPos* pos, MutableHandleValue dst)
+{
+  return newNode(AST_DELETE_OPTIONAL_EXPR, pos,
+                 "expression", expr,
+                 dst);
+}
+
+bool
 NodeBuilder::propertyPattern(HandleValue key, HandleValue patt, bool isShorthand, TokenPos* pos,
                              MutableHandleValue dst)
 {
@@ -2950,9 +2979,22 @@ ASTSerializer::expression(ParseNode* pn, MutableHandleValue dst)
       case PNK_GENEXP:
         return generatorExpression(pn->generatorExpr(), dst);
 
+      case PNK_DELETEOPTCHAIN: {
+        RootedValue expr(cx);
+        return expression(pn->pn_kid, &expr) &&
+               builder.deleteOptionalExpression(expr, &pn->pn_pos, dst);
+      }
+
+      case PNK_OPTCHAIN: {
+        RootedValue expr(cx);
+        return expression(pn->pn_kid, &expr) &&
+               builder.optionalExpression(expr, &pn->pn_pos, dst);
+      }
+
       case PNK_NEW:
       case PNK_TAGGED_TEMPLATE:
       case PNK_CALL:
+      case PNK_OPTCALL:
       case PNK_SUPERCALL:
       {
         ParseNode* next = pn->pn_head;
@@ -2984,13 +3026,15 @@ ASTSerializer::expression(ParseNode* pn, MutableHandleValue dst)
         if (pn->getKind() == PNK_TAGGED_TEMPLATE)
             return builder.taggedTemplate(callee, args, &pn->pn_pos, dst);
 
+        bool isOptional = pn->isKind(PNK_OPTCALL);
+
         // SUPERCALL is Call(super, args)
         return pn->isKind(PNK_NEW)
                ? builder.newExpression(callee, args, &pn->pn_pos, dst)
-
-            : builder.callExpression(callee, args, &pn->pn_pos, dst);
+               : builder.callExpression(callee, args, &pn->pn_pos, dst, isOptional);
       }
 
+      case PNK_OPTDOT:
       case PNK_DOT:
       {
         MOZ_ASSERT(pn->pn_pos.encloses(pn->pn_expr->pn_pos));
@@ -2999,7 +3043,7 @@ ASTSerializer::expression(ParseNode* pn, MutableHandleValue dst)
         RootedValue propname(cx);
         RootedAtom pnAtom(cx, pn->pn_atom);
 
-        if (pn->as<PropertyAccess>().isSuper()) {
+        if (pn->as<PropertyAccessBase>().isSuper()) {
             if (!builder.super(&pn->pn_expr->pn_pos, &expr))
                 return false;
         } else {
@@ -3007,10 +3051,14 @@ ASTSerializer::expression(ParseNode* pn, MutableHandleValue dst)
                 return false;
         }
 
+        bool isOptional = pn->isKind(PNK_OPTDOT);
+
         return identifier(pnAtom, nullptr, &propname) &&
-               builder.memberExpression(false, expr, propname, &pn->pn_pos, dst);
+               builder.memberExpression(false, expr, propname, &pn->pn_pos,
+                                        dst, isOptional);
       }
 
+      case PNK_OPTELEM:
       case PNK_ELEM:
       {
         MOZ_ASSERT(pn->pn_pos.encloses(pn->pn_left->pn_pos));
@@ -3018,7 +3066,7 @@ ASTSerializer::expression(ParseNode* pn, MutableHandleValue dst)
 
         RootedValue left(cx), right(cx);
 
-        if (pn->as<PropertyByValue>().isSuper()) {
+        if (pn->as<PropertyByValueBase>().isSuper()) {
             if (!builder.super(&pn->pn_left->pn_pos, &left))
                 return false;
         } else {
@@ -3026,8 +3074,11 @@ ASTSerializer::expression(ParseNode* pn, MutableHandleValue dst)
                 return false;
         }
 
+        bool isOptional = pn->isKind(PNK_OPTELEM);
+
         return expression(pn->pn_right, &right) &&
-               builder.memberExpression(true, left, right, &pn->pn_pos, dst);
+               builder.memberExpression(true, left, right, &pn->pn_pos, dst,
+                                        isOptional);
       }
 
       case PNK_CALLSITEOBJ:
diff --git a/js/src/jsast.tbl b/js/src/jsast.tbl
index a83ad74c6a..a50e31d7ba 100644
--- a/js/src/jsast.tbl
+++ b/js/src/jsast.tbl
@@ -27,10 +27,14 @@ ASTDEF(AST_LOGICAL_EXPR,          "LogicalExpression",              "logicalExpr
 ASTDEF(AST_UPDATE_EXPR,           "UpdateExpression",               "updateExpression")
 ASTDEF(AST_NEW_EXPR,              "NewExpression",                  "newExpression")
 ASTDEF(AST_CALL_EXPR,             "CallExpression",                 "callExpression")
+ASTDEF(AST_OPT_CALL_EXPR,         "OptionalCallExpression",         "optionalCallExpression")
 ASTDEF(AST_MEMBER_EXPR,           "MemberExpression",               "memberExpression")
+ASTDEF(AST_OPT_MEMBER_EXPR,       "OptionalMemberExpression",       "optionalMemberExpression")
 ASTDEF(AST_FUNC_EXPR,             "FunctionExpression",             "functionExpression")
 ASTDEF(AST_ARROW_EXPR,            "ArrowFunctionExpression",        "arrowFunctionExpression")
 ASTDEF(AST_ARRAY_EXPR,            "ArrayExpression",                "arrayExpression")
+ASTDEF(AST_DELETE_OPTIONAL_EXPR,  "DeleteOptionalExpression",       "deleteOptionalExpression")
+ASTDEF(AST_OPTIONAL_EXPR,         "OptionalExpression",             "optionalExpression")
 ASTDEF(AST_SPREAD_EXPR,           "SpreadExpression",               "spreadExpression")
 ASTDEF(AST_OBJECT_EXPR,           "ObjectExpression",               "objectExpression")
 ASTDEF(AST_THIS_EXPR,             "ThisExpression",                 "thisExpression")