一、尽量用Convey将所有测试用例的Convey汇总
用Convey嵌套的方法，将所有测试用例的Convey用一个大的Convey包裹起来，每个测试函数下只有一个大的Convey。比如下面的示例代码：
Go
import (
"testing"
. "github.com/smartystreets/goconvey/convey"
)
func TestStringSliceEqual(t *testing.T) {
Convey("TestStringSliceEqual", t, func() {
Convey("should return true when a != nil && b != nil", func() {
a := []string{"hello", "goconvey"}
b := []string{"hello", "goconvey"}
So(StringSliceEqual(a, b), ShouldBeTrue)
})
Convey("should return true when a ＝= nil && b ＝= nil", func() {
So(StringSliceEqual(nil, nil), ShouldBeTrue)
})
Convey("should return false when a ＝= nil && b != nil", func() {
a := []string(nil)
b := []string{}
So(StringSliceEqual(a, b), ShouldBeFalse)
})
Convey("should return false when a != nil && b != nil", func() {
a := []string{"hello", "world"}
b := []string{"hello", "goconvey"}
So(StringSliceEqual(a, b), ShouldBeFalse)
})
})
}这样做的好处是，看单测结果更为清晰直观：
Go
=== RUN TestStringSliceEqual
TestStringSliceEqual
should return true when a != nil && b != nil ✔
should return true when a ＝= nil && b ＝= nil ✔
should return false when a ＝= nil && b != nil ✔
should return false when a != nil && b != nil ✔
4 total assertions
--- PASS: TestStringSliceEqual (0.00s)
PASS
ok infra/alg 0.006s二、用GWT结构来描述复杂的测试用例
GWT结构嵌套了三层Convey：最外层是Given层，用来给定测试用例需要的数据；中间一层是When层，用来执行被测试的函数方法，得到result；最内层是Then层，用So来对result进行断言，看结果是否满足期望。
1 示例代码
示例代码如下：
Go
func TestStringSliceEqualIfBothNil(t *testing.T) {
Convey("Given two string slice which are both nil", t, func() {
var a []string = nil
var b []string = nil
Convey("When the comparision is done", func() {
result := StringSliceEqual(a, b)
Convey("Then the result should be true", func() {
So(result, ShouldBeTrue)
})
})
})
}
func TestStringSliceNotEqualIfNotBothNil(t *testing.T) {
Convey("Given two string slice which are both nil", t, func() {
a := []string(nil)
b := []string{}
Convey("When the comparision is done", func() {
result := StringSliceEqual(a, b)
Convey("Then the result should be false", func() {
So(result, ShouldBeFalse)
})
})
})
}
func TestStringSliceNotEqualIfBothNotNil(t *testing.T) {
Convey("Given two string slice which are both not nil", t, func() {
a := []string{"hello", "world"}
b := []string{"hello", "goconvey"}
Convey("When the comparision is done", func() {
result := StringSliceEqual(a, b)
Convey("Then the result should be false", func() {
So(result, ShouldBeFalse)
})
})
})
}在实际运用中，可以结合第一条方法构成四层嵌套来描述一个测试用例：
Go
func TestStringSliceEqual(t *testing.T) {
Convey("TestStringSliceEqualIfBothNotNil", t, func() {
Convey("Given two string slice which are both not nil", func() {
a := []string{"hello", "goconvey"}
b := []string{"hello", "goconvey"}
Convey("When the comparision is done", func() {
result := StringSliceEqual(a, b)
Convey("Then the result should be true", func() {
So(result, ShouldBeTrue)
})
})
})
})
Convey("TestStringSliceEqualIfBothNil", t, func() {
Convey("Given two string slice which are both nil", func() {
var a []string = nil
var b []string = nil
Convey("When the comparision is done", func() {
result := StringSliceEqual(a, b)
Convey("Then the result should be true", func() {
So(result, ShouldBeTrue)
})
})
})
})
Convey("TestStringSliceNotEqualIfNotBothNil", t, func() {
Convey("Given two string slice which are both nil", func() {
a := []string(nil)
b := []string{}
Convey("When the comparision is done", func() {
result := StringSliceEqual(a, b)
Convey("Then the result should be false", func() {
So(result, ShouldBeFalse)
})
})
})
})
Convey("TestStringSliceNotEqualIfBothNotNil", t, func() {
Convey("Given two string slice which are both not nil", func() {
a := []string{"hello", "world"}
b := []string{"hello", "goconvey"}
Convey("When the comparision is done", func() {
result := StringSliceEqual(a, b)
Convey("Then the result should be false", func() {
So(result, ShouldBeFalse)
})
})
})
})
}2 大坑
注意！Given层中最好只有一个Then，因为多个Then会导致每执行完一个Then就会再次执行一遍被测试的函数方法，导致多次执行的结果可能并不相同从而导致意料之外的错误（比如上面示例中的"result := StringSliceEqual(a, b)"）。所以如果选择使用GWT的结构，那么就要保证W中只有一个T，最好也要保证G中只有一个W。
三、自定义断言函数
断言函数So中第二个参数Assertion类型定义：
Go
type Assertion func(actual interface{}, expected ...interface{}) string返回空字符串表示断言成功，否则就是断言失败了。
1 自定义断言函数
所以我们自定义断言函数时也要注意这点，下面是一个参考示例：
Go
func ShouldSummerBeComming(actual interface{}, expected ...interface{}) string {
if actual == "summer" && expected[0] == "comming" {
return ""
} else {
return "summer is not comming!"
}
}上述代码中，第一个条件表示断言成功，其它所有情况都是断言失败。
2 在So中使用自定义的断言函数
Go
func TestSummer(t *testing.T) {
Convey("TestSummer", t, func() {
So("summer", ShouldSummerBeComming, "comming")
So("winter", ShouldSummerBeComming, "comming")
})
}测试结果：
Go
=== RUN TestSummer
TestSummer ✔✘
Failures:
* /Users/zhangxiaolong/Desktop/D/go-workspace/src/infra/alg/slice_test.go
Line 52:
summer is not comming!
2 total assertions
--- FAIL: TestSummer (0.00s)
FAIL
exit status 1
FAIL infra/alg 0.006s