如何测试执行过程

Question

This code is executing commands for binary and return std.out and std.error

func exe(bin string, args string, path string) (string, error string) {

    cmd := exec.Command(bin, strings.Split(args, " ")...)
    cmd.Dir = path
    stdoutBuf := &bytes.Buffer{}
    cmd.Stdout = stdoutBuf
    stdErrBuf := &bytes.Buffer{}
    cmd.Stderr = stdErrBuf
    cmd.Run()
    return stdoutBuf.String(), stdErrBuf.String()
}

The problem that I don't know how to run a good test for it which will be supported in each system e.g. if I try to run "echo" command the test run on Darwin and Linux but not on windows. how I should do it?

func Test_execute(t *testing.T) {
    type args struct {
        bin  string
        args string
        path string
    }
    tests := []struct {
        name       string
        args       args
        wantString string
        wantError  string
    }{
        // TODO: Add test cases.
    }
    for _, tt := range tests {
        t.Run(tt.name, func(t *testing.T) {
            gotString, gotError := exe(tt.args.bin, tt.args.args, tt.args.path)
            if gotString != tt.wantString {
                t.Errorf("exe() gotString = %v, want %v", gotString, tt.wantString)
            }
            if gotError != tt.wantError {
                t.Errorf("exe() gotError = %v, want %v", gotError, tt.wantError)
            }
        })
    }
}

I've searched on it and found this, https://www.joeshaw.org/testing-with-os-exec-and-testmain/ But now sure how to combine the env with my test...

Answer 1

Use Go build tags or file names. For example, for Linux and Windows:

a_linux_test.go (Linux file name):

package main

import "testing"

func TestLinuxA(t *testing.T) {
    t.Log("Linux A")
}

l_test.go (Linux build tag):

// +build linux

package main

import "testing"

func TestLinuxL(t *testing.T) {
    t.Log("Linux L")
}

a_windows_test.go (Windows file name):

package main

import "testing"

func TestWindowsA(t *testing.T) {
    t.Log("Windows A")
}

w_test.go (Windows build tag):

// +build windows

package main

import "testing"

func TestWindowsW(t *testing.T) {
    t.Log("Windows W")
}

Output (on Linux):

$ go test -v
=== RUN   TestLinuxA
--- PASS: TestLinuxA (0.00s)
    a_linux_test.go:6: Linux A
=== RUN   TestLinuxL
--- PASS: TestLinuxL (0.00s)
    l_test.go:8: Linux L
PASS
$ 

Output (on Windows):

>go test -v
=== RUN   TestWindowsA
--- PASS: TestWindowsA (0.00s)
    a_windows_test.go:6: Windows A
=== RUN   TestWindowsW
--- PASS: TestWindowsW (0.00s)
    w_test.go:8: Windows W
PASS
>

---

References:

Package build

Package testing

Command go