fix: an async generator code gen issue

If an assign node's expr contains any awaits, the await code gen shall hapen before the left symbol resolution, or the symbol may not dominant all uses.
This fix simply fix this issue by resolve symbol twice, this is, of cource, ugly, but it's the simplest way I can think of.

Author: Chronostasys

planglib/std/task/http.pi

@@ -45,7 +45,7 @@ impl HttpClient {
         let ip = await resolver.resolve_async(domain);
         let status = await self.socket.connect_async(ip, 80 as i32);
         // 发送请求
-        await self.socket.write_async(bytes);
+        status = await self.socket.write_async(bytes);
 
         // 使用1k缓冲区读取header
         let response_buf = [u8*1024;];

src/ast/node/statement.rs

@@ -587,19 +587,19 @@ impl Node for AssignNode {
                     return Err(ctx.add_diag(self.var.range().new_err(ErrorCode::NOT_ASSIGNABLE)));
                 }
                 let rel = rel.unwrap();
-                let ptr = rel.get_value();
                 let lpltype = rel.get_ty();
                 // 要走转换逻辑，所以不和下方分支统一
                 let value = ctx
-                    .emit_with_expectation(
-                        &mut self.exp,
-                        lpltype.clone(),
-                        self.var.range(),
-                        builder,
-                    )?
+                    .emit_with_expectation(&mut self.exp, lpltype.clone(), var.range(), builder)?
                     .get_value()
                     .unwrap()
                     .get_value();
+                let rel = var.emit(ctx, builder)?.get_value();
+                if rel.is_none() {
+                    return Err(ctx.add_diag(self.var.range().new_err(ErrorCode::NOT_ASSIGNABLE)));
+                }
+                let rel = rel.unwrap();
+                let ptr = rel.get_value();
                 if rel.is_const() {
                     return Err(ctx.add_diag(self.range.new_err(ErrorCode::ASSIGN_CONST)));
                 }