From 4fd9c29a77a2bce334cd32fcd6d92763a8aaa7c1 Mon Sep 17 00:00:00 2001
From: Willem Wyndham <willem@cs.umd.edu>
Date: Tue, 7 Jul 2020 11:29:01 -0400
Subject: [PATCH] fix: Do not serialize `?` on optional parameters with
 initializer in ASTBuilder (#1377)

---
 src/extra/ast.ts                              | 2 +-
 tests/parser/constructor.ts.fixture.ts        | 2 +-
 tests/parser/function.ts.fixture.ts           | 2 +-
 tests/parser/parameter-optional.ts            | 1 +
 tests/parser/parameter-optional.ts.fixture.ts | 1 +
 tests/parser/parameter-order.ts.fixture.ts    | 2 +-
 tests/parser/string-binding.ts.fixture.ts     | 2 +-
 7 files changed, 7 insertions(+), 5 deletions(-)
 create mode 100644 tests/parser/parameter-optional.ts
 create mode 100644 tests/parser/parameter-optional.ts.fixture.ts

diff --git a/src/extra/ast.ts b/src/extra/ast.ts
index 9044ac7aae..9c0dfa26c1 100644
--- a/src/extra/ast.ts
+++ b/src/extra/ast.ts
@@ -1613,7 +1613,7 @@ export class ASTBuilder {
     var type = node.type;
     var initializer = node.initializer;
     if (type) {
-      if (kind == ParameterKind.OPTIONAL) sb.push("?");
+      if (kind == ParameterKind.OPTIONAL && !initializer) sb.push("?");
       if (!isTypeOmitted(type)) {
         sb.push(": ");
         this.visitTypeNode(type);
diff --git a/tests/parser/constructor.ts.fixture.ts b/tests/parser/constructor.ts.fixture.ts
index 8b80d9e70f..481863215c 100644
--- a/tests/parser/constructor.ts.fixture.ts
+++ b/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) {}
 }
diff --git a/tests/parser/function.ts.fixture.ts b/tests/parser/function.ts.fixture.ts
index 277b48a93f..be705e4334 100644
--- a/tests/parser/function.ts.fixture.ts
+++ b/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 {
diff --git a/tests/parser/parameter-optional.ts b/tests/parser/parameter-optional.ts
new file mode 100644
index 0000000000..6bcd8c3b06
--- /dev/null
+++ b/tests/parser/parameter-optional.ts
@@ -0,0 +1 @@
+function optionalParam(a: string = ""): void {}
diff --git a/tests/parser/parameter-optional.ts.fixture.ts b/tests/parser/parameter-optional.ts.fixture.ts
new file mode 100644
index 0000000000..6bcd8c3b06
--- /dev/null
+++ b/tests/parser/parameter-optional.ts.fixture.ts
@@ -0,0 +1 @@
+function optionalParam(a: string = ""): void {}
diff --git a/tests/parser/parameter-order.ts.fixture.ts b/tests/parser/parameter-order.ts.fixture.ts
index 5398bfffe2..e972dfe4d7 100644
--- a/tests/parser/parameter-order.ts.fixture.ts
+++ b/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(5,37+1)
 // ERROR 1016: "A required parameter cannot follow an optional parameter." in parameter-order.ts(8,49+1)
 // ERROR 1016: "A required parameter cannot follow an optional parameter." in parameter-order.ts(11,67+1)
diff --git a/tests/parser/string-binding.ts.fixture.ts b/tests/parser/string-binding.ts.fixture.ts
index 92f9e21a5c..373498726c 100644
--- a/tests/parser/string-binding.ts.fixture.ts
+++ b/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)