Adding a struct to an existing struct incorrectly overwrites existing properties. Instead it should recursively add them.

[harrisont]

Repro:

.StructA =
[
  .ArrayOfStrings     = { 'String1', 'String2' }
  .String             = 'String'
]

.StructB =
[
  .ArrayOfStrings     = { 'String3' }
  .String             = '!'
]

.StructC = .StructA
         + .StructB

Actual .C result:

[
    .ArrayOfStrings = {
        'String3'
    }
    .String = '!'
]

Expected .C result:

[
    .ArrayOfStrings = {
        'String1',
        'String2',
        'String3'
    }
    .String = 'String!'
]

FASTBuild docs for adding structs

Problematic test case:

fastbuild-vscode/server/src/test/2-evaluator.test.ts

Lines 1235 to 1274 in b2c66c2

	it('should work on adding a struct to a struct', () => {
	const input = `
	.Struct1 = [
	.A=0
	.B=2
	]
	.Struct2 = [
	.A=1
	.C=3
	]
	.MyVar = .Struct1 + .Struct2
	`;
	const struct1ADefinition: VariableDefinition = { id: 1, range: createRange(2, 20, 22), name: 'A' };
	const struct1BDefinition: VariableDefinition = { id: 2, range: createRange(3, 20, 22), name: 'B' };
	const struct1 = Struct.from(Object.entries({
	A: new StructMember(0, [struct1ADefinition]),
	B: new StructMember(2, [struct1BDefinition]),
	}));
	const struct2ADefinition: VariableDefinition = { id: 4, range: createRange(6, 20, 22), name: 'A' };
	const struct2CDefinition: VariableDefinition = { id: 5, range: createRange(7, 20, 22), name: 'C' };
	const struct2 = Struct.from(Object.entries({
	A: new StructMember(1, [struct2ADefinition]),
	C: new StructMember(3, [struct2CDefinition]),
	}));
	assertEvaluatedVariablesValueEqual(input, [
	0,
	2,
	struct1,
	1,
	3,
	struct2,
	struct1,
	struct2,
	Struct.from(Object.entries({
	A: new StructMember(1, [struct2ADefinition]),
	B: new StructMember(2, [struct1BDefinition]),
	C: new StructMember(3, [struct2CDefinition]),
	}))
	]);
	});