From b83638245708e426a8d48a1d80797d58b567d48f Mon Sep 17 00:00:00 2001
From: dcode <dcode@dcode.io>
Date: Tue, 9 Jun 2020 23:39:32 +0200
Subject: [PATCH] Implicitly resolve to callables when resolving call
 expressions

---
 src/resolver.ts                               |  11 +
 .../function-expression.optimized.wat         | 111 +++++++
 tests/compiler/function-expression.ts         |  39 +++
 .../function-expression.untouched.wat         | 274 +++++++++++++++++-
 4 files changed, 431 insertions(+), 4 deletions(-)

diff --git a/src/resolver.ts b/src/resolver.ts
index 551e893c23..3cef9ca2c1 100644
--- a/src/resolver.ts
+++ b/src/resolver.ts
@@ -2384,6 +2384,17 @@ export class Resolver extends DiagnosticEmitter {
         if (!instance) return null;
         return instance.signature.returnType;
       }
+      case ElementKind.GLOBAL:
+      case ElementKind.LOCAL:
+      case ElementKind.FIELD: {
+        let varType = (<VariableLikeElement>target).type;
+        let varElement = this.getElementOfType(varType);
+        if (!varElement || varElement.kind != ElementKind.FUNCTION_TARGET) {
+          break;
+        }
+        target = varElement;
+        // fall-through
+      }
       case ElementKind.FUNCTION_TARGET: {
         return (<FunctionTarget>target).signature.returnType;
       }
diff --git a/tests/compiler/function-expression.optimized.wat b/tests/compiler/function-expression.optimized.wat
index a0f1087d58..7d019dffa1 100644
--- a/tests/compiler/function-expression.optimized.wat
+++ b/tests/compiler/function-expression.optimized.wat
@@ -1,5 +1,116 @@
 (module
+ (type $none_=>_i32 (func (result i32)))
+ (type $i32_=>_i32 (func (param i32) (result i32)))
+ (type $i32_i32_=>_i32 (func (param i32 i32) (result i32)))
+ (type $none_=>_none (func))
+ (type $i32_i32_i32_i32_=>_none (func (param i32 i32 i32 i32)))
+ (import "env" "abort" (func $~lib/builtins/abort (param i32 i32 i32 i32)))
  (memory $0 1)
  (data (i32.const 1024) ",\00\00\00\01\00\00\00\01\00\00\00,\00\00\00f\00u\00n\00c\00t\00i\00o\00n\00-\00e\00x\00p\00r\00e\00s\00s\00i\00o\00n\00.\00t\00s")
+ (table $0 18 funcref)
+ (elem (i32.const 1) $start:function-expression~anonymous|0 $start:function-expression~anonymous|0 $start:function-expression~someName $start:function-expression~anonymous|2 $start:function-expression~anonymous|3 $start:function-expression~anonymous|4 $start:function-expression~anonymous|5 $start:function-expression~anonymous|3 $start:function-expression~anonymous|4 $start:function-expression~anonymous|5 $start:function-expression~anonymous|2 $function-expression/testGlobal~anonymous|0~anonymous|0 $function-expression/testGlobal~anonymous|0 $function-expression/testGlobal~anonymous|0~anonymous|0 $function-expression/testLocal~anonymous|0 $function-expression/testGlobal~anonymous|0~anonymous|0 $function-expression/testField~anonymous|0)
  (export "memory" (memory $0))
+ (start $~start)
+ (func $start:function-expression~anonymous|0 (param $0 i32) (result i32)
+  local.get $0
+ )
+ (func $start:function-expression~someName
+  nop
+ )
+ (func $start:function-expression~anonymous|2 (result i32)
+  i32.const 1
+ )
+ (func $start:function-expression~anonymous|3 (param $0 i32) (param $1 i32) (result i32)
+  local.get $0
+  local.get $1
+  i32.add
+ )
+ (func $start:function-expression~anonymous|4 (param $0 i32) (param $1 i32) (result i32)
+  local.get $0
+ )
+ (func $start:function-expression~anonymous|5 (param $0 i32) (param $1 i32) (result i32)
+  i32.const 42
+ )
+ (func $function-expression/testGlobal~anonymous|0~anonymous|0 (param $0 i32) (result i32)
+  local.get $0
+  i32.const 24
+  i32.add
+ )
+ (func $function-expression/testGlobal~anonymous|0 (result i32)
+  i32.const 12
+ )
+ (func $function-expression/testLocal~anonymous|0 (result i32)
+  i32.const 14
+ )
+ (func $function-expression/testField~anonymous|0 (result i32)
+  i32.const 16
+ )
+ (func $~start
+  (local $0 i32)
+  (local $1 i32)
+  i32.const 1120
+  memory.size
+  local.tee $1
+  i32.const 16
+  i32.shl
+  local.tee $0
+  i32.gt_u
+  if
+   local.get $1
+   i32.const 66655
+   local.get $0
+   i32.sub
+   i32.const -65536
+   i32.and
+   i32.const 16
+   i32.shr_u
+   local.tee $0
+   local.get $1
+   local.get $0
+   i32.gt_s
+   select
+   memory.grow
+   i32.const 0
+   i32.lt_s
+   if
+    local.get $0
+    memory.grow
+    i32.const 0
+    i32.lt_s
+    if
+     unreachable
+    end
+   end
+  end
+  i32.const 1088
+  i32.const 16
+  i32.store
+  i32.const 1092
+  i32.const 1
+  i32.store
+  i32.const 1096
+  i32.const 3
+  i32.store
+  i32.const 1100
+  i32.const 4
+  i32.store
+  i32.const 1104
+  i32.const 17
+  i32.store
+  i32.const 1
+  i32.const 1104
+  i32.load
+  call_indirect (type $none_=>_i32)
+  call_indirect (type $i32_=>_i32)
+  i32.const 25
+  i32.ne
+  if
+   i32.const 0
+   i32.const 1040
+   i32.const 82
+   i32.const 3
+   call $~lib/builtins/abort
+   unreachable
+  end
+ )
 )
diff --git a/tests/compiler/function-expression.ts b/tests/compiler/function-expression.ts
index 294eaee7bf..8fe0fdbf2e 100644
--- a/tests/compiler/function-expression.ts
+++ b/tests/compiler/function-expression.ts
@@ -43,3 +43,42 @@ function testNullable(b: boolean): (() => i32) | null {
   }
 }
 assert(testNullable(false) == null);
+
+// see: https://github.com/AssemblyScript/assemblyscript/issues/1289
+
+var globalFunc: () => (x: i32) => i32;
+function testGlobal(): void {
+  globalFunc = (): (x:i32) => i32 => {
+    let myFunc = (x: i32): i32 => {
+      return 24 + x;
+    };
+    return myFunc;
+  };
+  assert(globalFunc()(1) == 25);
+}
+testGlobal();
+
+function testLocal(): void {
+  let localFunc = (): (x:i32) => i32 => {
+    let myFunc = (x: i32): i32 => {
+      return 24 + x;
+    };
+    return myFunc;
+  };
+  assert(localFunc()(1) == 25);
+}
+testLocal();
+
+class FieldClass {
+  constructor(public fieldFunc: () => (x: i32) => i32) {}
+}
+function testField(): void {
+  let fieldInst = new FieldClass((): (x:i32) => i32 => {
+    let myFunc = (x: i32): i32 => {
+      return 24 + x;
+    };
+    return myFunc;
+  });
+  assert(fieldInst.fieldFunc()(1) == 25);
+}
+testField();
diff --git a/tests/compiler/function-expression.untouched.wat b/tests/compiler/function-expression.untouched.wat
index 32a6e38e23..4e8ee52c68 100644
--- a/tests/compiler/function-expression.untouched.wat
+++ b/tests/compiler/function-expression.untouched.wat
@@ -1,19 +1,24 @@
 (module
- (type $i32_i32_=>_i32 (func (param i32 i32) (result i32)))
- (type $none_=>_i32 (func (result i32)))
  (type $i32_=>_i32 (func (param i32) (result i32)))
+ (type $none_=>_i32 (func (result i32)))
+ (type $i32_i32_=>_i32 (func (param i32 i32) (result i32)))
  (type $none_=>_none (func))
+ (type $i32_=>_none (func (param i32)))
  (type $i32_i32_i32_i32_=>_none (func (param i32 i32 i32 i32)))
  (import "env" "abort" (func $~lib/builtins/abort (param i32 i32 i32 i32)))
  (memory $0 1)
  (data (i32.const 16) ",\00\00\00\01\00\00\00\01\00\00\00,\00\00\00f\00u\00n\00c\00t\00i\00o\00n\00-\00e\00x\00p\00r\00e\00s\00s\00i\00o\00n\00.\00t\00s\00")
- (table $0 12 funcref)
- (elem (i32.const 1) $start:function-expression~anonymous|0 $start:function-expression~anonymous|1 $start:function-expression~someName $start:function-expression~anonymous|2 $start:function-expression~anonymous|3 $start:function-expression~anonymous|4 $start:function-expression~anonymous|5 $function-expression/testOmittedReturn1~anonymous|0 $function-expression/testOmittedReturn2~anonymous|0 $function-expression/testOmittedReturn3~anonymous|0 $function-expression/testNullable~anonymous|0)
+ (table $0 18 funcref)
+ (elem (i32.const 1) $start:function-expression~anonymous|0 $start:function-expression~anonymous|1 $start:function-expression~someName $start:function-expression~anonymous|2 $start:function-expression~anonymous|3 $start:function-expression~anonymous|4 $start:function-expression~anonymous|5 $function-expression/testOmittedReturn1~anonymous|0 $function-expression/testOmittedReturn2~anonymous|0 $function-expression/testOmittedReturn3~anonymous|0 $function-expression/testNullable~anonymous|0 $function-expression/testGlobal~anonymous|0~anonymous|0 $function-expression/testGlobal~anonymous|0 $function-expression/testLocal~anonymous|0~anonymous|0 $function-expression/testLocal~anonymous|0 $function-expression/testField~anonymous|0~anonymous|0 $function-expression/testField~anonymous|0)
  (global $function-expression/f1 (mut i32) (i32.const 1))
  (global $~argumentsLength (mut i32) (i32.const 0))
  (global $function-expression/f2 (mut i32) (i32.const 2))
  (global $function-expression/f3 (mut i32) (i32.const 3))
  (global $function-expression/f4 (mut i32) (i32.const 4))
+ (global $function-expression/globalFunc (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 $~lib/heap/__heap_base i32 (i32.const 76))
  (export "memory" (memory $0))
  (start $~start)
  (func $start:function-expression~anonymous|0 (param $0 i32) (result i32)
@@ -81,6 +86,254 @@
   end
   unreachable
  )
+ (func $function-expression/testGlobal~anonymous|0~anonymous|0 (param $0 i32) (result i32)
+  i32.const 24
+  local.get $0
+  i32.add
+ )
+ (func $function-expression/testGlobal~anonymous|0 (result i32)
+  (local $0 i32)
+  i32.const 12
+  local.set $0
+  local.get $0
+ )
+ (func $function-expression/testGlobal
+  (local $0 i32)
+  i32.const 13
+  global.set $function-expression/globalFunc
+  i32.const 1
+  i32.const 0
+  global.set $~argumentsLength
+  global.get $function-expression/globalFunc
+  call_indirect (type $none_=>_i32)
+  local.set $0
+  i32.const 1
+  global.set $~argumentsLength
+  local.get $0
+  call_indirect (type $i32_=>_i32)
+  i32.const 25
+  i32.eq
+  i32.eqz
+  if
+   i32.const 0
+   i32.const 32
+   i32.const 57
+   i32.const 3
+   call $~lib/builtins/abort
+   unreachable
+  end
+ )
+ (func $function-expression/testLocal~anonymous|0~anonymous|0 (param $0 i32) (result i32)
+  i32.const 24
+  local.get $0
+  i32.add
+ )
+ (func $function-expression/testLocal~anonymous|0 (result i32)
+  (local $0 i32)
+  i32.const 14
+  local.set $0
+  local.get $0
+ )
+ (func $function-expression/testLocal
+  (local $0 i32)
+  (local $1 i32)
+  i32.const 15
+  local.set $0
+  i32.const 1
+  i32.const 0
+  global.set $~argumentsLength
+  local.get $0
+  call_indirect (type $none_=>_i32)
+  local.set $1
+  i32.const 1
+  global.set $~argumentsLength
+  local.get $1
+  call_indirect (type $i32_=>_i32)
+  i32.const 25
+  i32.eq
+  i32.eqz
+  if
+   i32.const 0
+   i32.const 32
+   i32.const 68
+   i32.const 3
+   call $~lib/builtins/abort
+   unreachable
+  end
+ )
+ (func $~lib/rt/stub/maybeGrowMemory (param $0 i32)
+  (local $1 i32)
+  (local $2 i32)
+  (local $3 i32)
+  (local $4 i32)
+  (local $5 i32)
+  memory.size
+  local.set $1
+  local.get $1
+  i32.const 16
+  i32.shl
+  local.set $2
+  local.get $0
+  local.get $2
+  i32.gt_u
+  if
+   local.get $0
+   local.get $2
+   i32.sub
+   i32.const 65535
+   i32.add
+   i32.const 65535
+   i32.const -1
+   i32.xor
+   i32.and
+   i32.const 16
+   i32.shr_u
+   local.set $3
+   local.get $1
+   local.tee $4
+   local.get $3
+   local.tee $5
+   local.get $4
+   local.get $5
+   i32.gt_s
+   select
+   local.set $4
+   local.get $4
+   memory.grow
+   i32.const 0
+   i32.lt_s
+   if
+    local.get $3
+    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 (param $0 i32) (param $1 i32) (result i32)
+  (local $2 i32)
+  (local $3 i32)
+  (local $4 i32)
+  (local $5 i32)
+  (local $6 i32)
+  local.get $0
+  i32.const 1073741808
+  i32.gt_u
+  if
+   unreachable
+  end
+  global.get $~lib/rt/stub/offset
+  i32.const 16
+  i32.add
+  local.set $2
+  local.get $0
+  i32.const 15
+  i32.add
+  i32.const 15
+  i32.const -1
+  i32.xor
+  i32.and
+  local.tee $3
+  i32.const 16
+  local.tee $4
+  local.get $3
+  local.get $4
+  i32.gt_u
+  select
+  local.set $5
+  local.get $2
+  local.get $5
+  i32.add
+  call $~lib/rt/stub/maybeGrowMemory
+  local.get $2
+  i32.const 16
+  i32.sub
+  local.set $6
+  local.get $6
+  local.get $5
+  i32.store
+  i32.const 1
+  drop
+  local.get $6
+  i32.const 1
+  i32.store offset=4
+  local.get $6
+  local.get $1
+  i32.store offset=8
+  local.get $6
+  local.get $0
+  i32.store offset=12
+  local.get $2
+ )
+ (func $~lib/rt/stub/__retain (param $0 i32) (result i32)
+  local.get $0
+ )
+ (func $function-expression/FieldClass#constructor (param $0 i32) (param $1 i32) (result i32)
+  local.get $0
+  i32.eqz
+  if
+   i32.const 4
+   i32.const 3
+   call $~lib/rt/stub/__alloc
+   call $~lib/rt/stub/__retain
+   local.set $0
+  end
+  local.get $0
+  local.get $1
+  i32.store
+  local.get $0
+ )
+ (func $function-expression/testField~anonymous|0~anonymous|0 (param $0 i32) (result i32)
+  i32.const 24
+  local.get $0
+  i32.add
+ )
+ (func $function-expression/testField~anonymous|0 (result i32)
+  (local $0 i32)
+  i32.const 16
+  local.set $0
+  local.get $0
+ )
+ (func $~lib/rt/stub/__release (param $0 i32)
+  nop
+ )
+ (func $function-expression/testField
+  (local $0 i32)
+  (local $1 i32)
+  i32.const 0
+  i32.const 17
+  call $function-expression/FieldClass#constructor
+  local.set $0
+  i32.const 1
+  i32.const 0
+  global.set $~argumentsLength
+  local.get $0
+  i32.load
+  call_indirect (type $none_=>_i32)
+  local.set $1
+  i32.const 1
+  global.set $~argumentsLength
+  local.get $1
+  call_indirect (type $i32_=>_i32)
+  i32.const 25
+  i32.eq
+  i32.eqz
+  if
+   i32.const 0
+   i32.const 32
+   i32.const 82
+   i32.const 3
+   call $~lib/builtins/abort
+   unreachable
+  end
+  local.get $0
+  call $~lib/rt/stub/__release
+ )
  (func $start:function-expression
   i32.const 1
   i32.const 1
@@ -236,6 +489,19 @@
    call $~lib/builtins/abort
    unreachable
   end
+  call $function-expression/testGlobal
+  call $function-expression/testLocal
+  global.get $~lib/heap/__heap_base
+  i32.const 15
+  i32.add
+  i32.const 15
+  i32.const -1
+  i32.xor
+  i32.and
+  global.set $~lib/rt/stub/startOffset
+  global.get $~lib/rt/stub/startOffset
+  global.set $~lib/rt/stub/offset
+  call $function-expression/testField
  )
  (func $~start
   call $start:function-expression