簡介
日常開發中, 測試是不能缺少的.
Go 標準庫中有一個叫做 testing 的測試框架, 可以用于單元測試和性能測試.
它是和命令 go test 集成使用的.
測試文件是以后綴 _test.go 命名的, 通常和被測試的文件放在同一個包中.
單元測試
單元測試的格式形如:
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func TestAbs(t *testing.T) { got := Abs(-1) if got != 1 { t.Errorf("Abs(-1) = %d; want 1", got) }} |
在 util 目錄下創建一個文件 util_test.go, 添加一個單元測試:
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package utilimport "testing"// 普通的測試func TestGenShortID(t *testing.T) { shortID, err := GenShortID() if shortID == "" || err != nil { t.Error("GenShortID failed") }} |
然后, 在根目錄下運行 go test -v ./util/, 測試結果如下:
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root@592402321ce7:/workspace# go test -v ./util/=== RUN TestGenShortID--- PASS: TestGenShortID (0.00s)PASSok tzh.com/web/util 0.006s |
性能測試
性能測試的結果形如:
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func BenchmarkHello(b *testing.B) { for i := 0; i < b.N; i++ { fmt.Sprintf("hello") }} |
在 util_test.go 添加性能測試:
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// 性能測試func BenchmarkGenShortID(b *testing.B) { for i := 0; i < b.N; i++ { GenShortID() }} |
運行結果如下(使用 --run=none 避免運行普通的測試函數, 因為一般不可能有函數名匹配 none):
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root@592402321ce7:/workspace# go test -v -bench="BenchmarkGenShortID$" --run=none ./util/goos: linuxgoarch: amd64pkg: tzh.com/web/utilBenchmarkGenShortID-2 507237 2352 ns/opPASSok tzh.com/web/util 1.229s |
這說明, 平均每次運行 GenShortID() 需要 2352 納秒.
性能分析
運行測試的時候, 可以指定一些參數, 生成性能文件 profile.
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-blockprofile block.out Write a goroutine blocking profile to the specified file when all tests are complete. Writes test binary as -c would.-blockprofilerate n Control the detail provided in goroutine blocking profiles by calling runtime.SetBlockProfileRate with n. See 'go doc runtime.SetBlockProfileRate'. The profiler aims to sample, on average, one blocking event every n nanoseconds the program spends blocked. By default, if -test.blockprofile is set without this flag, all blocking events are recorded, equivalent to -test.blockprofilerate=1.-coverprofile cover.out Write a coverage profile to the file after all tests have passed. Sets -cover.-cpuprofile cpu.out Write a CPU profile to the specified file before exiting. Writes test binary as -c would.-memprofile mem.out Write an allocation profile to the file after all tests have passed. Writes test binary as -c would.-memprofilerate n Enable more precise (and expensive) memory allocation profiles by setting runtime.MemProfileRate. See 'go doc runtime.MemProfileRate'. To profile all memory allocations, use -test.memprofilerate=1.-mutexprofile mutex.out Write a mutex contention profile to the specified file when all tests are complete. Writes test binary as -c would.-mutexprofilefraction n Sample 1 in n stack traces of goroutines holding a contended mutex. |
使用下面的命令, 生成 CPU 的 profile:
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go test -v -bench="BenchmarkGenShortID$" --run=none -cpuprofile cpu.out ./util/ |
當前目錄下, 應該會生成 cpu.out 文件和 util.test 文件.
使用下面的命令, 觀察耗時操作:
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# 進入交互模式go tool pprof cpu.outtop |
安裝 Graphviz 后可以生成可視化的分析圖.
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apt install graphvizgo tool pprof -http=":" cpu.out |
測試覆蓋率
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root@592402321ce7:/workspace# go test -v -coverprofile=cover.out ./util/=== RUN TestGenShortID--- PASS: TestGenShortID (0.00s)PASScoverage: 9.1% of statementsok tzh.com/web/util 0.005s coverage: 9.1% of statementsroot@592402321ce7:/workspace# go tool cover -func=cover.outtzh.com/web/util/util.go:12: GenShortID 100.0%tzh.com/web/util/util.go:17: GetReqID 0.0%tzh.com/web/util/util.go:22: TimeToStr 0.0%tzh.com/web/util/util.go:30: GetTag 0.0%total: (statements) 9.1% |
使用 -coverprofile=cover.out 選項可以統計測試覆蓋率.使用 go tool cover -func=cover.out 可以查看更加詳細的測試覆蓋率結果,
統計每個函數的測試覆蓋率.
總結
測試是開發中非常重要的一個環節, 用于保證軟件質量, 切不可偷懶.
當前部分的代碼
作為版本 v0.15.0
以上就是本文的全部內容，希望對大家的學習有所幫助，也希望大家多多支持服務器之家。
原文鏈接：https://juejin.im/post/5dc37eb8e51d452a066999bf
