[typescript] Size-prefixed root accessors not taking into account size prefix (#5717)

* [typescript/javascript] Size-prefixed root accessor needs to account for the size prefix.

* [typescript] Add parentheses after "new" expression.

* Update generated test files

src/idl_gen_js_ts.cpp

@@ -600,6 +600,10 @@ class JsTsGenerator : public BaseGenerator {
     }
   }
 
+  std::string GenerateNewExpression(const std::string &object_name) {
+    return "new " + object_name + (lang_.language == IDLOptions::kTs ? "()" : "");
+  }
+
   void GenerateRootAccessor(StructDef &struct_def, std::string *code_ptr,
                             std::string &code, std::string &object_name,
                             bool size_prefixed) {
@@ -619,7 +623,10 @@ class JsTsGenerator : public BaseGenerator {
                 "Root" + Verbose(struct_def, "As");
         code += " = function(bb, obj) {\n";
       }
-      code += "  return (obj || new " + object_name;
+      if (size_prefixed) {
+        code += "  bb.setPosition(bb.position() + flatbuffers.SIZE_PREFIX_LENGTH);\n";
+      }
+      code += "  return (obj || " + GenerateNewExpression(object_name);
       code += ").__init(bb.readInt32(bb.position()) + bb.position(), bb);\n";
       code += "};\n\n";
     }
@@ -858,12 +865,12 @@ class JsTsGenerator : public BaseGenerator {
             }
 
             if (struct_def.fixed) {
-              code += "  return (obj || new " + type;
+              code += "  return (obj || " + GenerateNewExpression(type);
               code += ").__init(this.bb_pos";
               code +=
                   MaybeAdd(field.value.offset) + ", " + GenBBAccess() + ");\n";
             } else {
-              code += offset_prefix + "(obj || new " + type + ").__init(";
+              code += offset_prefix + "(obj || " + GenerateNewExpression(type) + ").__init(";
               code += field.value.type.struct_def->fixed
                           ? "this.bb_pos + offset"
                           : GenBBAccess() + ".__indirect(this.bb_pos + offset)";
@@ -945,7 +952,7 @@ class JsTsGenerator : public BaseGenerator {
             }
 
             if (vectortype.base_type == BASE_TYPE_STRUCT) {
-              code += offset_prefix + "(obj || new " + vectortypename;
+              code += offset_prefix + "(obj || " + GenerateNewExpression(vectortypename);
               code += ").__init(";
               code += vectortype.struct_def->fixed
                           ? index

tests/monster_test_generated.js

@@ -185,6 +185,7 @@ MyGame.InParentNamespace.getRootAsInParentNamespace = function(bb, obj) {
  * @returns {MyGame.InParentNamespace}
  */
 MyGame.InParentNamespace.getSizePrefixedRootAsInParentNamespace = function(bb, obj) {
+  bb.setPosition(bb.position() + flatbuffers.SIZE_PREFIX_LENGTH);
   return (obj || new MyGame.InParentNamespace).__init(bb.readInt32(bb.position()) + bb.position(), bb);
 };
 
@@ -254,6 +255,7 @@ MyGame.Example2.Monster.getRootAsMonster = function(bb, obj) {
  * @returns {MyGame.Example2.Monster}
  */
 MyGame.Example2.Monster.getSizePrefixedRootAsMonster = function(bb, obj) {
+  bb.setPosition(bb.position() + flatbuffers.SIZE_PREFIX_LENGTH);
   return (obj || new MyGame.Example2.Monster).__init(bb.readInt32(bb.position()) + bb.position(), bb);
 };
 
@@ -407,6 +409,7 @@ MyGame.Example.TestSimpleTableWithEnum.getRootAsTestSimpleTableWithEnum = functi
  * @returns {MyGame.Example.TestSimpleTableWithEnum}
  */
 MyGame.Example.TestSimpleTableWithEnum.getSizePrefixedRootAsTestSimpleTableWithEnum = function(bb, obj) {
+  bb.setPosition(bb.position() + flatbuffers.SIZE_PREFIX_LENGTH);
   return (obj || new MyGame.Example.TestSimpleTableWithEnum).__init(bb.readInt32(bb.position()) + bb.position(), bb);
 };
 
@@ -764,6 +767,7 @@ MyGame.Example.Stat.getRootAsStat = function(bb, obj) {
  * @returns {MyGame.Example.Stat}
  */
 MyGame.Example.Stat.getSizePrefixedRootAsStat = function(bb, obj) {
+  bb.setPosition(bb.position() + flatbuffers.SIZE_PREFIX_LENGTH);
   return (obj || new MyGame.Example.Stat).__init(bb.readInt32(bb.position()) + bb.position(), bb);
 };
 
@@ -918,6 +922,7 @@ MyGame.Example.Referrable.getRootAsReferrable = function(bb, obj) {
  * @returns {MyGame.Example.Referrable}
  */
 MyGame.Example.Referrable.getSizePrefixedRootAsReferrable = function(bb, obj) {
+  bb.setPosition(bb.position() + flatbuffers.SIZE_PREFIX_LENGTH);
   return (obj || new MyGame.Example.Referrable).__init(bb.readInt32(bb.position()) + bb.position(), bb);
 };
 
@@ -1022,6 +1027,7 @@ MyGame.Example.Monster.getRootAsMonster = function(bb, obj) {
  * @returns {MyGame.Example.Monster}
  */
 MyGame.Example.Monster.getSizePrefixedRootAsMonster = function(bb, obj) {
+  bb.setPosition(bb.position() + flatbuffers.SIZE_PREFIX_LENGTH);
   return (obj || new MyGame.Example.Monster).__init(bb.readInt32(bb.position()) + bb.position(), bb);
 };
 
@@ -2833,6 +2839,7 @@ MyGame.Example.TypeAliases.getRootAsTypeAliases = function(bb, obj) {
  * @returns {MyGame.Example.TypeAliases}
  */
 MyGame.Example.TypeAliases.getSizePrefixedRootAsTypeAliases = function(bb, obj) {
+  bb.setPosition(bb.position() + flatbuffers.SIZE_PREFIX_LENGTH);
   return (obj || new MyGame.Example.TypeAliases).__init(bb.readInt32(bb.position()) + bb.position(), bb);
 };
 

tests/namespace_test/namespace_test1_generated.js

@@ -71,6 +71,7 @@ NamespaceA.NamespaceB.TableInNestedNS.getRootAsTableInNestedNS = function(bb, ob
  * @returns {NamespaceA.NamespaceB.TableInNestedNS}
  */
 NamespaceA.NamespaceB.TableInNestedNS.getSizePrefixedRootAsTableInNestedNS = function(bb, obj) {
+  bb.setPosition(bb.position() + flatbuffers.SIZE_PREFIX_LENGTH);
   return (obj || new NamespaceA.NamespaceB.TableInNestedNS).__init(bb.readInt32(bb.position()) + bb.position(), bb);
 };
 

tests/namespace_test/namespace_test1_generated.ts

@@ -35,7 +35,7 @@ __init(i:number, bb:flatbuffers.ByteBuffer):TableInNestedNS {
  * @returns TableInNestedNS
  */
 static getRootAsTableInNestedNS(bb:flatbuffers.ByteBuffer, obj?:TableInNestedNS):TableInNestedNS {
-  return (obj || new TableInNestedNS).__init(bb.readInt32(bb.position()) + bb.position(), bb);
+  return (obj || new TableInNestedNS()).__init(bb.readInt32(bb.position()) + bb.position(), bb);
 };
 
 /**
@@ -44,7 +44,8 @@ static getRootAsTableInNestedNS(bb:flatbuffers.ByteBuffer, obj?:TableInNestedNS)
  * @returns TableInNestedNS
  */
 static getSizePrefixedRootAsTableInNestedNS(bb:flatbuffers.ByteBuffer, obj?:TableInNestedNS):TableInNestedNS {
-  return (obj || new TableInNestedNS).__init(bb.readInt32(bb.position()) + bb.position(), bb);
+  bb.setPosition(bb.position() + flatbuffers.SIZE_PREFIX_LENGTH);
+  return (obj || new TableInNestedNS()).__init(bb.readInt32(bb.position()) + bb.position(), bb);
 };
 
 /**

tests/namespace_test/namespace_test2_generated.js

@@ -59,6 +59,7 @@ NamespaceA.TableInFirstNS.getRootAsTableInFirstNS = function(bb, obj) {
  * @returns {NamespaceA.TableInFirstNS}
  */
 NamespaceA.TableInFirstNS.getSizePrefixedRootAsTableInFirstNS = function(bb, obj) {
+  bb.setPosition(bb.position() + flatbuffers.SIZE_PREFIX_LENGTH);
   return (obj || new NamespaceA.TableInFirstNS).__init(bb.readInt32(bb.position()) + bb.position(), bb);
 };
 
@@ -199,6 +200,7 @@ NamespaceC.TableInC.getRootAsTableInC = function(bb, obj) {
  * @returns {NamespaceC.TableInC}
  */
 NamespaceC.TableInC.getSizePrefixedRootAsTableInC = function(bb, obj) {
+  bb.setPosition(bb.position() + flatbuffers.SIZE_PREFIX_LENGTH);
   return (obj || new NamespaceC.TableInC).__init(bb.readInt32(bb.position()) + bb.position(), bb);
 };
 
@@ -306,6 +308,7 @@ NamespaceA.SecondTableInA.getRootAsSecondTableInA = function(bb, obj) {
  * @returns {NamespaceA.SecondTableInA}
  */
 NamespaceA.SecondTableInA.getSizePrefixedRootAsSecondTableInA = function(bb, obj) {
+  bb.setPosition(bb.position() + flatbuffers.SIZE_PREFIX_LENGTH);
   return (obj || new NamespaceA.SecondTableInA).__init(bb.readInt32(bb.position()) + bb.position(), bb);
 };
 

tests/namespace_test/namespace_test2_generated.ts

@@ -26,7 +26,7 @@ __init(i:number, bb:flatbuffers.ByteBuffer):TableInFirstNS {
  * @returns TableInFirstNS
  */
 static getRootAsTableInFirstNS(bb:flatbuffers.ByteBuffer, obj?:TableInFirstNS):TableInFirstNS {
-  return (obj || new TableInFirstNS).__init(bb.readInt32(bb.position()) + bb.position(), bb);
+  return (obj || new TableInFirstNS()).__init(bb.readInt32(bb.position()) + bb.position(), bb);
 };
 
 /**
@@ -35,7 +35,8 @@ static getRootAsTableInFirstNS(bb:flatbuffers.ByteBuffer, obj?:TableInFirstNS):T
  * @returns TableInFirstNS
  */
 static getSizePrefixedRootAsTableInFirstNS(bb:flatbuffers.ByteBuffer, obj?:TableInFirstNS):TableInFirstNS {
-  return (obj || new TableInFirstNS).__init(bb.readInt32(bb.position()) + bb.position(), bb);
+  bb.setPosition(bb.position() + flatbuffers.SIZE_PREFIX_LENGTH);
+  return (obj || new TableInFirstNS()).__init(bb.readInt32(bb.position()) + bb.position(), bb);
 };
 
 /**
@@ -44,7 +45,7 @@ static getSizePrefixedRootAsTableInFirstNS(bb:flatbuffers.ByteBuffer, obj?:Table
  */
 fooTable(obj?:NS8755221360535654258.NamespaceA.NamespaceB.TableInNestedNS):NS8755221360535654258.NamespaceA.NamespaceB.TableInNestedNS|null {
   var offset = this.bb!.__offset(this.bb_pos, 4);
-  return offset ? (obj || new NS8755221360535654258.NamespaceA.NamespaceB.TableInNestedNS).__init(this.bb!.__indirect(this.bb_pos + offset), this.bb!) : null;
+  return offset ? (obj || new NS8755221360535654258.NamespaceA.NamespaceB.TableInNestedNS()).__init(this.bb!.__indirect(this.bb_pos + offset), this.bb!) : null;
 };
 
 /**
@@ -76,7 +77,7 @@ mutate_foo_enum(value:NS8755221360535654258.NamespaceA.NamespaceB.EnumInNestedNS
  */
 fooStruct(obj?:NS8755221360535654258.NamespaceA.NamespaceB.StructInNestedNS):NS8755221360535654258.NamespaceA.NamespaceB.StructInNestedNS|null {
   var offset = this.bb!.__offset(this.bb_pos, 8);
-  return offset ? (obj || new NS8755221360535654258.NamespaceA.NamespaceB.StructInNestedNS).__init(this.bb_pos + offset, this.bb!) : null;
+  return offset ? (obj || new NS8755221360535654258.NamespaceA.NamespaceB.StructInNestedNS()).__init(this.bb_pos + offset, this.bb!) : null;
 };
 
 /**
@@ -153,7 +154,7 @@ __init(i:number, bb:flatbuffers.ByteBuffer):TableInC {
  * @returns TableInC
  */
 static getRootAsTableInC(bb:flatbuffers.ByteBuffer, obj?:TableInC):TableInC {
-  return (obj || new TableInC).__init(bb.readInt32(bb.position()) + bb.position(), bb);
+  return (obj || new TableInC()).__init(bb.readInt32(bb.position()) + bb.position(), bb);
 };
 
 /**
@@ -162,7 +163,8 @@ static getRootAsTableInC(bb:flatbuffers.ByteBuffer, obj?:TableInC):TableInC {
  * @returns TableInC
  */
 static getSizePrefixedRootAsTableInC(bb:flatbuffers.ByteBuffer, obj?:TableInC):TableInC {
-  return (obj || new TableInC).__init(bb.readInt32(bb.position()) + bb.position(), bb);
+  bb.setPosition(bb.position() + flatbuffers.SIZE_PREFIX_LENGTH);
+  return (obj || new TableInC()).__init(bb.readInt32(bb.position()) + bb.position(), bb);
 };
 
 /**
@@ -171,7 +173,7 @@ static getSizePrefixedRootAsTableInC(bb:flatbuffers.ByteBuffer, obj?:TableInC):T
  */
 referToA1(obj?:NamespaceA.TableInFirstNS):NamespaceA.TableInFirstNS|null {
   var offset = this.bb!.__offset(this.bb_pos, 4);
-  return offset ? (obj || new NamespaceA.TableInFirstNS).__init(this.bb!.__indirect(this.bb_pos + offset), this.bb!) : null;
+  return offset ? (obj || new NamespaceA.TableInFirstNS()).__init(this.bb!.__indirect(this.bb_pos + offset), this.bb!) : null;
 };
 
 /**
@@ -180,7 +182,7 @@ referToA1(obj?:NamespaceA.TableInFirstNS):NamespaceA.TableInFirstNS|null {
  */
 referToA2(obj?:NamespaceA.SecondTableInA):NamespaceA.SecondTableInA|null {
   var offset = this.bb!.__offset(this.bb_pos, 6);
-  return offset ? (obj || new NamespaceA.SecondTableInA).__init(this.bb!.__indirect(this.bb_pos + offset), this.bb!) : null;
+  return offset ? (obj || new NamespaceA.SecondTableInA()).__init(this.bb!.__indirect(this.bb_pos + offset), this.bb!) : null;
 };
 
 /**
@@ -248,7 +250,7 @@ __init(i:number, bb:flatbuffers.ByteBuffer):SecondTableInA {
  * @returns SecondTableInA
  */
 static getRootAsSecondTableInA(bb:flatbuffers.ByteBuffer, obj?:SecondTableInA):SecondTableInA {
-  return (obj || new SecondTableInA).__init(bb.readInt32(bb.position()) + bb.position(), bb);
+  return (obj || new SecondTableInA()).__init(bb.readInt32(bb.position()) + bb.position(), bb);
 };
 
 /**
@@ -257,7 +259,8 @@ static getRootAsSecondTableInA(bb:flatbuffers.ByteBuffer, obj?:SecondTableInA):S
  * @returns SecondTableInA
  */
 static getSizePrefixedRootAsSecondTableInA(bb:flatbuffers.ByteBuffer, obj?:SecondTableInA):SecondTableInA {
-  return (obj || new SecondTableInA).__init(bb.readInt32(bb.position()) + bb.position(), bb);
+  bb.setPosition(bb.position() + flatbuffers.SIZE_PREFIX_LENGTH);
+  return (obj || new SecondTableInA()).__init(bb.readInt32(bb.position()) + bb.position(), bb);
 };
 
 /**
@@ -266,7 +269,7 @@ static getSizePrefixedRootAsSecondTableInA(bb:flatbuffers.ByteBuffer, obj?:Secon
  */
 referToC(obj?:NamespaceC.TableInC):NamespaceC.TableInC|null {
   var offset = this.bb!.__offset(this.bb_pos, 4);
-  return offset ? (obj || new NamespaceC.TableInC).__init(this.bb!.__indirect(this.bb_pos + offset), this.bb!) : null;
+  return offset ? (obj || new NamespaceC.TableInC()).__init(this.bb!.__indirect(this.bb_pos + offset), this.bb!) : null;
 };
 
 /**

tests/union_vector/union_vector_generated.js

@@ -67,6 +67,7 @@ Attacker.getRootAsAttacker = function(bb, obj) {
  * @returns {Attacker}
  */
 Attacker.getSizePrefixedRootAsAttacker = function(bb, obj) {
+  bb.setPosition(bb.position() + flatbuffers.SIZE_PREFIX_LENGTH);
   return (obj || new Attacker).__init(bb.readInt32(bb.position()) + bb.position(), bb);
 };
 
@@ -287,6 +288,7 @@ Movie.getRootAsMovie = function(bb, obj) {
  * @returns {Movie}
  */
 Movie.getSizePrefixedRootAsMovie = function(bb, obj) {
+  bb.setPosition(bb.position() + flatbuffers.SIZE_PREFIX_LENGTH);
   return (obj || new Movie).__init(bb.readInt32(bb.position()) + bb.position(), bb);
 };
 

tests/union_vector/union_vector_generated.ts

@@ -37,7 +37,7 @@ __init(i:number, bb:flatbuffers.ByteBuffer):Attacker {
  * @returns Attacker
  */
 static getRootAsAttacker(bb:flatbuffers.ByteBuffer, obj?:Attacker):Attacker {
-  return (obj || new Attacker).__init(bb.readInt32(bb.position()) + bb.position(), bb);
+  return (obj || new Attacker()).__init(bb.readInt32(bb.position()) + bb.position(), bb);
 };
 
 /**
@@ -46,7 +46,8 @@ static getRootAsAttacker(bb:flatbuffers.ByteBuffer, obj?:Attacker):Attacker {
  * @returns Attacker
  */
 static getSizePrefixedRootAsAttacker(bb:flatbuffers.ByteBuffer, obj?:Attacker):Attacker {
-  return (obj || new Attacker).__init(bb.readInt32(bb.position()) + bb.position(), bb);
+  bb.setPosition(bb.position() + flatbuffers.SIZE_PREFIX_LENGTH);
+  return (obj || new Attacker()).__init(bb.readInt32(bb.position()) + bb.position(), bb);
 };
 
 /**
@@ -230,7 +231,7 @@ __init(i:number, bb:flatbuffers.ByteBuffer):Movie {
  * @returns Movie
  */
 static getRootAsMovie(bb:flatbuffers.ByteBuffer, obj?:Movie):Movie {
-  return (obj || new Movie).__init(bb.readInt32(bb.position()) + bb.position(), bb);
+  return (obj || new Movie()).__init(bb.readInt32(bb.position()) + bb.position(), bb);
 };
 
 /**
@@ -239,7 +240,8 @@ static getRootAsMovie(bb:flatbuffers.ByteBuffer, obj?:Movie):Movie {
  * @returns Movie
  */
 static getSizePrefixedRootAsMovie(bb:flatbuffers.ByteBuffer, obj?:Movie):Movie {
-  return (obj || new Movie).__init(bb.readInt32(bb.position()) + bb.position(), bb);
+  bb.setPosition(bb.position() + flatbuffers.SIZE_PREFIX_LENGTH);
+  return (obj || new Movie()).__init(bb.readInt32(bb.position()) + bb.position(), bb);
 };
 
 /**