从测试，恐慌：sql：连接返回，永远不会出来

Question

我在测试的运行时遇到以下恐慌：

panic: sql: connection returned that was never out

考试

实际测试是test suite的一部分，因此定义如下：

func (suite *RowsSuite) TestReadFrom_SanityTest() {
    t := suite.T()

    rows := new(sql.Rows)
    *rows = suite.nonEmptyRows

    assert.True(t, rows.Next())
    // hit the function like it's supposed to be hit
    err := ReadFrom(rows,
        suite.fnStubFalse,
        suite.spots[0],
        suite.spots[1],
        suite.spots[2])

    // There better be no error
    if !assert.Nil(t, err) {
        t.Error(err.ToString(false))
    }

}

正在测试的代码

我负责测试这个功能：

// ReadFrom reads values from `rows` into `valuePlaceholders`
func ReadFrom(rows *sql.Rows,
    readerFunc func(rowIndex int, readValues ...interface{}) (bool, *errors.ErrorSt),
    valuePlaceholders ...interface{}) (err *errors.ErrorSt) {

    rowLine := 1
    for rows.Next() {
        if err := rows.Scan(valuePlaceholders...); err != nil {
            return errors.Database().AddDetails(err.Error(), valuePlaceholders)
        }
        if readerFunc != nil {
            skipRest, err := readerFunc(rowLine, valuePlaceholders...)
            if err != nil {
                return err
            }
            if skipRest {
                break
            }
        }
        rowLine++
    }
    if rowLine == 1 {
        return errors.Get(appErrors.ACNoRows)
    }
    return nil
}

建立

suite.fnStubFalse只是一个函数存根返回false,nil suite.spots只是一个大小为3的[]*interface{}。简单地说，它是Scan的三个点。

与测试相关的其余定义在此辅助方法中定义，该方法在套件设置中调用：

func (suite *RowsSuite) setupRowStates() {
    // for throwing fatal error right away
    t := suite.T()
    // fire up the mock
    suite.db, suite.mock, suite.err = sqlmock.New()
    // if there's an error, fatally throw it right away!
    if !assert.Nilf(t,
        suite.err,
        "Error with initializing a stub database connection") {
        t.Fatal()
    }

    // define the possible expectant result sets
    noRows := sqlmock.NewRows(suite.columns)
    nonEmptyRows := sqlmock.NewRows(suite.columns).
        AddRow(381, "Beans", 1.59).
        AddRow(34981, "Frozen Pizza", 5.49)

    // define our sql behavior
    regex := "^SELECT (.+) FROM items$"
    sql := "SELECT (item_id, item_name, item_price) FROM items"

    specificRegex := "^SELECT (.+) FROM items (.+)$"
    specificSQL := `
    SELECT (item_id, item_name, item_price) FROM items i
    INNER JOIN stock s
    ON s.item_id = i.item_id
    WHERE TIME_TO_SEC(s.stock_time) > TIME_TO_SEC(NOW())`

    // setup general query to return non-empty rows
    suite.mock.ExpectQuery(regex).
        WillReturnRows(nonEmptyRows)
    // setup specific query to return empty rows
    suite.mock.ExpectQuery(specificRegex).
        WillReturnRows(noRows)

    // hit both queries right now and store the state of their
    //  return values, terminating right away on any errors
    var err error
    rows, err := suite.db.Query(sql)
    if err != nil {
        t.Fatal(err.Error())
    }
    suite.nonEmptyRows = *rows
    emptyRows, err := suite.db.Query(specificSQL)
    if err != nil {
        t.Fatal(err.Error())
    }
    suite.noRows = *emptyRows

}

完整的错误

这种怪异：

Running tool: C:\Go\bin\go.exe test -timeout 30s ezsoft\apiserver_sdk\db -run ^TestRowsSuite$

panic: sql: connection returned that was never out

goroutine 22 [running]:
database/sql.(*DB).putConn(0xc04204d400, 0xc04212a080, 0x0, 0x0, 0xc04213de01)
    C:/Go/src/database/sql/sql.go:1158 +0x351
database/sql.(*driverConn).releaseConn(0xc04212a080, 0x0, 0x0)
    C:/Go/src/database/sql/sql.go:383 +0x53
database/sql.(*driverConn).(database/sql.releaseConn)-fm(0x0, 0x0)
    C:/Go/src/database/sql/sql.go:706 +0x45
database/sql.(*Rows).close(0xc04212a100, 0x899be0, 0xc042048380, 0x0, 0x0)
    C:/Go/src/database/sql/sql.go:2932 +0x159
database/sql.(*Rows).awaitDone(0xc04212a100, 0x89d260, 0xc042050b00, 0x0, 0x0)
    C:/Go/src/database/sql/sql.go:2588 +0x12f
created by database/sql.(*Rows).initContextClose
    C:/Go/src/database/sql/sql.go:2572 +0xa3
FAIL    ezsoft/apiserver_sdk/db 0.429s
Error: Tests failed.

使用第三方库

我使用testify和go-sqlmock（我可能只是通过使用它来简单地查询查询，因为我不得不在设置中跳过箍。）

我不知道造成这种失败的原因是什么。当我删除测试并运行套件时，一切正常

Answer 1

事实证明我正在过度思考这种情况。

我通过将两个行状态存储为指针来修复它，然后在RowsSuite.SetupTest中设置它们（在测试级别，而不是套件级别）。从那里开始，我只是在测试中获取其中一个状态，我很高兴。即，而不是这（在C ++中可以正常工作）：

func (suite *RowsSuite) TestReadFrom_SanityTest() {
    t := suite.T()

    rows := new(sql.Rows)
    *rows = suite.nonEmptyRows

    assert.True(t, rows.Next())
    // hit the function like it's supposed to be hit
    err := ReadFrom(rows,
        suite.fnStubFalse,
        suite.spots[0],
        suite.spots[1],
        suite.spots[2])

    // There better be no error
    if !assert.Nil(t, err) {
        t.Error(err.ToString(false))
    }

}

我这样做了：

func (suite *RowsSuite) TestReadFrom_SanityTest() {
    t := suite.T()

    rows := suite.nonEmptyRows

    // hit the function like it's supposed to be hit
    errSt := ReadFrom(rows,
        suite.fnStubFalse,
        suite.spots[0],
        suite.spots[1],
        suite.spots[2])

    // There better be no error
    if !assert.Nil(t, errSt) {
        t.Error(errSt.ToString(false))
    }

}

其中nonEmptyRows是在测试运行之前设置的状态之一