Fix 'new' parsing precedence & allow omitting parenthesis

Author: dcodeIO

src/parser.ts

@@ -3266,7 +3266,7 @@ export class Parser extends DiagnosticEmitter {
 
       // NewExpression
       if (token == Token.NEW) {
-        operand = this.parseExpression(tn, Precedence.CALL);
+        operand = this.parseExpression(tn, Precedence.GROUPING);
         if (!operand) return null;
         if (operand.kind == NodeKind.CALL) {
           return Node.createNewExpression(
@@ -3275,6 +3275,11 @@ export class Parser extends DiagnosticEmitter {
             (<CallExpression>operand).arguments,
             tn.range(startPos, tn.pos)
           );
+        } else if (operand.kind == NodeKind.IDENTIFIER) { // new Class;
+          return Node.createNewExpression(
+            operand, null, [],
+            tn.range(startPos, tn.pos)
+          );
         } else {
           this.error(
             DiagnosticCode.This_expression_is_not_constructable,

tests/compiler/new.json

@@ -0,0 +1,5 @@
+{
+  "asc_flags": [
+    "--runtime none"
+  ]
+}

tests/compiler/new.optimized.wat

@@ -0,0 +1,108 @@
+(module
+ (type $FUNCSIG$vi (func (param i32)))
+ (type $FUNCSIG$v (func))
+ (type $FUNCSIG$ii (func (param i32) (result i32)))
+ (memory $0 0)
+ (global $new/ref (mut i32) (i32.const 0))
+ (global $~lib/rt/stub/startOffset (mut i32) (i32.const 0))
+ (global $~lib/rt/stub/offset (mut i32) (i32.const 0))
+ (global $new/gen (mut i32) (i32.const 0))
+ (export "memory" (memory $0))
+ (start $start)
+ (func $~lib/rt/stub/maybeGrowMemory (; 0 ;) (type $FUNCSIG$vi) (param $0 i32)
+  (local $1 i32)
+  (local $2 i32)
+  local.get $0
+  memory.size
+  local.tee $2
+  i32.const 16
+  i32.shl
+  local.tee $1
+  i32.gt_u
+  if
+   local.get $2
+   local.get $0
+   local.get $1
+   i32.sub
+   i32.const 65535
+   i32.add
+   i32.const -65536
+   i32.and
+   i32.const 16
+   i32.shr_u
+   local.tee $1
+   local.get $2
+   local.get $1
+   i32.gt_s
+   select
+   memory.grow
+   i32.const 0
+   i32.lt_s
+   if
+    local.get $1
+    memory.grow
+    i32.const 0
+    i32.lt_s
+    if
+     unreachable
+    end
+   end
+  end
+  local.get $0
+  global.set $~lib/rt/stub/offset
+ )
+ (func $~lib/rt/stub/__alloc (; 1 ;) (type $FUNCSIG$ii) (param $0 i32) (result i32)
+  (local $1 i32)
+  (local $2 i32)
+  global.get $~lib/rt/stub/offset
+  i32.const 16
+  i32.add
+  local.tee $2
+  i32.const 16
+  i32.add
+  call $~lib/rt/stub/maybeGrowMemory
+  local.get $2
+  i32.const 16
+  i32.sub
+  local.tee $1
+  i32.const 16
+  i32.store
+  local.get $1
+  i32.const -1
+  i32.store offset=4
+  local.get $1
+  local.get $0
+  i32.store offset=8
+  local.get $1
+  i32.const 0
+  i32.store offset=12
+  local.get $2
+ )
+ (func $start:new (; 2 ;) (type $FUNCSIG$v)
+  i32.const 16
+  global.set $~lib/rt/stub/startOffset
+  i32.const 16
+  global.set $~lib/rt/stub/offset
+  i32.const 3
+  call $~lib/rt/stub/__alloc
+  global.set $new/ref
+  i32.const 3
+  call $~lib/rt/stub/__alloc
+  global.set $new/ref
+  i32.const 3
+  call $~lib/rt/stub/__alloc
+  global.set $new/ref
+  i32.const 4
+  call $~lib/rt/stub/__alloc
+  global.set $new/gen
+  i32.const 4
+  call $~lib/rt/stub/__alloc
+  global.set $new/gen
+ )
+ (func $start (; 3 ;) (type $FUNCSIG$v)
+  call $start:new
+ )
+ (func $null (; 4 ;) (type $FUNCSIG$v)
+  nop
+ )
+)

tests/compiler/new.ts

@@ -0,0 +1,16 @@
+class Ref {
+  get ref(): Ref { return this; }
+}
+
+var ref: Ref;
+ref = new Ref();
+ref = new Ref;
+ref = new Ref().ref;
+
+class Gen<T> {
+  get gen(): Gen<T> { return this; }
+}
+
+var gen: Gen<i32>;
+gen = new Gen<i32>();
+gen = new Gen<i32>().gen;