Fix some array function parsing and serialization issues

Quite similar to #256 and also uses its test, but also fixes the serializer and doesn't try to parse an untyped 'x => x'.

tests/parser/arrow-functions.ts

@@ -0,0 +1,10 @@
+// array function
+(x): i32 => x;
+(x: i32) => x;
+(x?) => x;
+(x?, y?) => x;
+(x?: i32) => x;
+
+// not an array function
+(b ? x : y);
+(b ? f : g)();

tests/parser/arrow-functions.ts.fixture.ts

@@ -0,0 +1,11 @@
+(x): i32 => x;
+(x: i32) => x;
+(x?) => x;
+(x?, y?) => x;
+(x?: i32) => x;
+(b ? x : y);
+(b ? f : g)();
+// ERROR 1110: "Type expected." in arrow-functions.ts:3:8
+// ERROR 1110: "Type expected." in arrow-functions.ts:4:4
+// ERROR 1110: "Type expected." in arrow-functions.ts:5:8
+// ERROR 1110: "Type expected." in arrow-functions.ts:6:9

tests/parser/class.ts.fixture.ts

@@ -9,8 +9,8 @@ export class Valid<T> {
 }
 export class Invalid<T> {
   constructor<T>() {}
-  instanceFunction():  {}
-  get instanceGetter<T>(a: i32):  {}
+  instanceFunction() {}
+  get instanceGetter<T>(a: i32) {}
   set instanceSetter<T>() {}
 }
 // ERROR 1092: "Type parameters cannot appear on a constructor declaration." in class.ts:13:13

tests/parser/constructor.ts.fixture.ts

@@ -4,5 +4,5 @@ class MyClass {
   constructor(a: i32, b: i32) {}
 }
 class MyClassImplicit {
-  constructor(public a: i32, private readonly b: i32 = 2, c: i32 = 3) {}
+  constructor(public a: i32, private readonly b?: i32 = 2, c?: i32 = 3) {}
 }

tests/parser/function.ts.fixture.ts

@@ -1,5 +1,5 @@
 function simple(): void {}
-function typeparams<T, V extends T>(a: V | null = null): void {}
+function typeparams<T, V extends T>(a?: V | null = null): void {}
 @decorator()
 function withdecorator(): void {}
 function withthis(this: i32): i32 {

tests/parser/parameter-order.ts.fixture.ts

@@ -2,7 +2,7 @@ function restValid(a: i32, ...b: Array<i32>): void {}
 function optionalValid(a: i32, b?: i32): void {}
 function restParameterMustBeLast(...a: Array<i32>, b: i32): void {}
 function optionalCannotPrecedeRequired(a?: i32, b: i32): void {}
-function optionalWithInitializerCannotPrecedeRequired(a: i32 = 1, b: i32): void {}
+function optionalWithInitializerCannotPrecedeRequired(a?: i32 = 1, b: i32): void {}
 // ERROR 1014: "A rest parameter must be last in a parameter list." in parameter-order.ts:5:36
 // ERROR 1016: "A required parameter cannot follow an optional parameter." in parameter-order.ts:8:48
 // ERROR 1016: "A required parameter cannot follow an optional parameter." in parameter-order.ts:11:66

tests/parser/string-binding.ts.fixture.ts

@@ -1,7 +1,7 @@
 @binding(BindingCall.NEW, [BindingType.STRING], BindingType.OBJECT_HANDLE)
 export class ExternalString {
   @binding(BindingCall.FUNCTION, [BindingType.U32, BindingType.U32], BindingType.OBJECT_HANDLE)
-  static fromCharCode(char: u16, schar: u16 = <u16>-1): String {
+  static fromCharCode(char: u16, schar?: u16 = <u16>-1): String {
     return unreachable();
   }
   @binding(BindingCall.FUNCTION, [BindingType.U32], BindingType.OBJECT_HANDLE)