Fix async function returning const number error · Pull Request !7894 · OpenHarmony/arkcompiler_ets_frontend

1. Fix async function returning const number error
---
### **Issue**
https://gitee.com/openharmony/arkcompiler_ets_frontend/issues/ICT0XV?from=project-issue

### **Reason**
Fix adds a check to determine whether the type inside the Promise is a number.

### **Description**
Original question:
1.In an async function, returning a const-declared number causes a compilation error.
```
async function test(): Promise<number> {  
    const n1: number = 1;
    return n1;
}    
TypeError: Type 'int' is not compatible with the enclosing method's return type 'Promise<Double> | Double' 
```
Error Cause:

```
    if (auto *preferredType =
            GetAppropriatePreferredType(expr->PreferredType(), [&](Type *tp) { return checker->CheckIfNumeric(tp); });
        preferredType != nullptr && !expr->IsFolded() &&
        CheckIfLiteralValueIsAppropriate(checker, preferredType, expr)) {
        type = preferredType->Clone(checker);
```

```
static Type *GetAppropriatePreferredType(Type *originalType, std::function<bool(Type *)> const &predicate)
{
    if (originalType == nullptr) {
        return nullptr;
    }

while (originalType->IsETSTypeAliasType()) {
        if (predicate(originalType)) {
            return originalType;
        }
        originalType = originalType->AsETSTypeAliasType()->GetTargetType();
    }

if (predicate(originalType)) {
        return originalType;
    }

```
The cause of the error is that, due to constant folding, number n1 is parsed as an int, while the function’s return type is parsed as a double, resulting in a type mismatch in subsequent checks. In the previous code, there was a call to GetAppropriatePreferredType, which could be used to determine whether the return value was of type number; if so, that type would be assigned to n1. However, in an async function, the return type is wrapped in a Promise, preventing it from being recognized as a number type, and thus making it impossible to convert the type of n1.

Fix:

```
    if (originalType->IsETSAsyncFuncReturnType() &&
        originalType->AsETSAsyncFuncReturnType()->GetPromiseTypeArg()->IsETSObjectType() &&
        predicate(
            originalType->AsETSAsyncFuncReturnType()->GetPromiseTypeArg()->AsETSObjectType()->GetOriginalBaseType())) {
        return originalType->AsETSAsyncFuncReturnType()->GetPromiseTypeArg()->AsETSObjectType()->GetOriginalBaseType();
    }
```
The solution is to extract the number type wrapped inside the return type’s Promise

### **Scheme**
Fix adds a check to determine whether the type inside the Promise is a number.

### **Tests**
ninja tests passed 
L0 tests passed

Change-Id:8348b403f7b22ee1aea8c3d562b77c63007ceae5

类型	指派人员	状态
审查	@egavrin 由 CODEOWNERS 文件第 18 行指派为审查者	进行中 (0/1人)
审查	godmiaozi zhuoli72 gavin1012_hw 徐城 Ilya Trubachev Urakov Alexandr Chernykh Sergey Vsevolod Pukhov	进行中 (0/1人)
测试	openharmony_ci 已测试通过	已完成 (1/1人)

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