issue-37947-incorrect.go

package main

import (
	"context"
	"fmt"
	"go.mongodb.org/mongo-driver/bson"
	"go.mongodb.org/mongo-driver/mongo"
	"go.mongodb.org/mongo-driver/mongo/options"
)


func findAllValues() chan bson.M {
	connStr := "mongodb://localhost:27018"
	var mongoClient, _ = mongo.Connect(context.TODO(), options.Client().ApplyURI(connStr))

	items := mongoClient.Database("example").Collection("values")
	cursor, _ := items.Find(context.TODO(), bson.M{})

	channel := make(chan bson.M)
	go func() {
		for cursor.Next(context.TODO()) {
			var value bson.M
			cursor.Decode(&value)
			value = bson.M{"value": "ok"}
			channel <- value
		}
		close(channel)
	}()

	return channel
}

func main() {
	chnlWithRecords := findAllValues()
	for i := range chnlWithRecords {
		fmt.Println(i)
	}
}



// Output is correct because we get only map[value:ok] in output

go run works-well.go       
map[value:ok]
map[value:ok]
map[value:ok]
map[value:ok]
map[value:ok]
map[value:ok]
map[value:ok]
map[value:ok]
map[value:ok]
...