[TS] Fix generation of struct members in object api (#7148)

* Fix C/C++ Create<Type>Direct with sorted vectors

If a struct has a key the vector has to be sorted. To sort the vector
you can't use "const".

* Changes due to code review

* Improve code readability

* Add generate of JSON schema to string to lib

* option indent_step is supported

* Remove unused variables

* Fix break in test

* Fix style to be consistent with rest of the code

* [TS] Fix reserved words as arguments (#6955)

* [TS] Fix generation of reserved words in object api (#7106)

* [TS] Fix generation of object api

* [TS] Fix MakeCamel -> ConvertCase

* [TS] Add test for struct of struct of struct

* Update generated files

* Add missing files

* [TS] Fix query of null/undefined fields in object api

tests/my-game/example/struct-of-structs-of-structs.ts

@@ -0,0 +1,74 @@
+// automatically generated by the FlatBuffers compiler, do not modify
+
+import * as flatbuffers from 'flatbuffers';
+
+import { StructOfStructs, StructOfStructsT } from '../../my-game/example/struct-of-structs';
+
+
+export class StructOfStructsOfStructs {
+  bb: flatbuffers.ByteBuffer|null = null;
+  bb_pos = 0;
+__init(i:number, bb:flatbuffers.ByteBuffer):StructOfStructsOfStructs {
+  this.bb_pos = i;
+  this.bb = bb;
+  return this;
+}
+
+a(obj?:StructOfStructs):StructOfStructs|null {
+  return (obj || new StructOfStructs()).__init(this.bb_pos, this.bb!);
+}
+
+static getFullyQualifiedName():string {
+  return 'MyGame.Example.StructOfStructsOfStructs';
+}
+
+static sizeOf():number {
+  return 20;
+}
+
+static createStructOfStructsOfStructs(builder:flatbuffers.Builder, a_a_id: number, a_a_distance: number, a_b_a: number, a_b_b: number, a_c_id: number, a_c_distance: number):flatbuffers.Offset {
+  builder.prep(4, 20);
+  builder.prep(4, 20);
+  builder.prep(4, 8);
+  builder.writeInt32(a_c_distance);
+  builder.writeInt32(a_c_id);
+  builder.prep(2, 4);
+  builder.pad(1);
+  builder.writeInt8(a_b_b);
+  builder.writeInt16(a_b_a);
+  builder.prep(4, 8);
+  builder.writeInt32(a_a_distance);
+  builder.writeInt32(a_a_id);
+  return builder.offset();
+}
+
+
+unpack(): StructOfStructsOfStructsT {
+  return new StructOfStructsOfStructsT(
+    (this.a() !== null ? this.a()!.unpack() : null)
+  );
+}
+
+
+unpackTo(_o: StructOfStructsOfStructsT): void {
+  _o.a = (this.a() !== null ? this.a()!.unpack() : null);
+}
+}
+
+export class StructOfStructsOfStructsT {
+constructor(
+  public a: StructOfStructsT|null = null
+){}
+
+
+pack(builder:flatbuffers.Builder): flatbuffers.Offset {
+  return StructOfStructsOfStructs.createStructOfStructsOfStructs(builder,
+    (this.a?.a?.id ?? 0),
+    (this.a?.a?.distance ?? 0),
+    (this.a?.b?.a ?? 0),
+    (this.a?.b?.b ?? 0),
+    (this.a?.c?.id ?? 0),
+    (this.a?.c?.distance ?? 0)
+  );
+}
+}

tests/my-game/example/struct-of-structs.ts

@@ -77,12 +77,12 @@ constructor(
 
 pack(builder:flatbuffers.Builder): flatbuffers.Offset {
   return StructOfStructs.createStructOfStructs(builder,
-    (this.a === null ? 0 : this.a.id!),
-    (this.a === null ? 0 : this.a.distance!),
-    (this.b === null ? 0 : this.b.a!),
-    (this.b === null ? 0 : this.b.b!),
-    (this.c === null ? 0 : this.c.id!),
-    (this.c === null ? 0 : this.c.distance!)
+    (this.a?.id ?? 0),
+    (this.a?.distance ?? 0),
+    (this.b?.a ?? 0),
+    (this.b?.b ?? 0),
+    (this.c?.id ?? 0),
+    (this.c?.distance ?? 0)
   );
 }
 }

tests/my-game/example/vec3.ts

@@ -130,8 +130,8 @@ pack(builder:flatbuffers.Builder): flatbuffers.Offset {
     this.z,
     this.test1,
     this.test2,
-    (this.test3 === null ? 0 : this.test3.a!),
-    (this.test3 === null ? 0 : this.test3.b!)
+    (this.test3?.a ?? 0),
+    (this.test3?.b ?? 0)
   );
 }
 }