Question

我想测试golang命令行应用的输出，但我不太确定如何使用go的测试库。

我们说我有一个这样的程序：

package main

import (
    "flag"
    "fmt"
)

func main() {
    const (
        cityDefault = "San Francisco"
        cityDoc     = "the city you want the forecast for"
    )
    var city string
    flag.StringVar(&city, "city", cityDefault, cityDoc)
    flag.StringVar(&city, "c", cityDefault, cityDoc)
    flag.Parse()

    fmt.Println(city)
}

我想测试这两个：

$ ./myapp -c "Los Angeles"
$ ./myapp -city "Los Angeles"

...输出Lost Angeles。所以，我想问题是，你如何进行集成测试golang命令行应用程序的输出？

Answer 1

这是解析命令行参数的一个不好的例子，但它显示了我用来在我的应用程序中测试命令行参数的框架。

<强> main.go

float uvv, u, v, diffU, diffV, F, K, lapU, lapV;
float[] MINI = { 0.00, 0.01, 0.03, 0.005 }; 
float[] MAXI = { 0.15, 0.08, 0.11, 0.05 }; 

PImage reactionDiffusion (PImage img) {

  int W = img.width, H = img.height;  
  int[][] offsetW = new int[W][2], offsetH = new int[H][2];
  float[][]  U = new float[W][H],  V = new float[W][H];
  float time = millis();

  //  INITIALISATION
  for (int i = 0; i < W; ++i) {
    for (int j = 0; j < H; ++j) {
      U[i][j] = 0.15 ;
      V[i][j] = 0.7  ;
    }
  }  

  // init parameters
  float[][][] fkuv = new float[W][H][4];  

  for (int i = 0; i<W; ++i){
    for (int j = 0; j<H; ++j){
        fkuv[i][j][0] = map( i, 0, H, MINI[0], MAXI[0] );
        fkuv[i][j][1] = map( j, 0, W, MAXI[1], MINI[0] );  
        fkuv[i][j][2] = map(150,0,200,0,MAXI[2]);
        fkuv[i][j][3] = map(50,0,200,0,MAXI[3]);
    }
  }
  //Set up offsets
  for (int i=0; i < W; ++i) { offsetW[i][0] = i-1; offsetW[i][1] = i+1; }
  for (int i=0; i < H; ++i) { offsetH[i][0] = i-1; offsetH[i][1] = i+1; }
  offsetW[0][0] = 0; offsetW[W-1][1] = W-1;
  offsetH[0][0] = 0; offsetH[H-1][1] = H-1;

  for (int n = 0; n< 2000 ; ++n){ // itérations
    for (int i = 0; i < W; ++i) {
      for (int j = 0; j < H; ++j) {

        F = fkuv[i][j][0] ;
        K = fkuv[i][j][1] ;

        u = U[i][j];  
        v = V[i][j]; 

        uvv = u*v*v;
        lapU = U[offsetW[i][0]][j] +U[offsetW[i][1]][j] +U[i][offsetH[j][0]] +U[i][offsetH[j][1]] -4*u;
        lapV = V[offsetW[i][0]][j] +V[offsetW[i][1]][j] +V[i][offsetH[j][0]] +V[i][offsetH[j][1]] -4*v;

        U[i][j] += ( U*lapU - uvv + F*(1 - u) ) * 1.38 ;
        V[i][j] += ( V*lapV + uvv - (K+F)*v   ) * 0.63 ;
      } 
    }
  }
  img.loadPixels();
    int pShift;
    for (int i = 0; i < W; i++) {
      for (int j = 0; j < H; j++) {
        pShift = int( U[i][j]*255 ) ;
        img.pixels[j*W+i] = 0xff000000 | (pShift << 16) | (pShift << 8) | pShift  ;
      }
    }
  img.updatePixels();

  println("time : "+ ( millis()-time ) /1000) ; 

  return img;
}

<强> main_unit_test.go

package main

import (
    "log"
    "os"
)

func main() {
    var city string
    parseFlags(&city, os.Args)

    log.Println(city)
}

func parseFlags(result *string, args []string) {
    cityDefault := "San Francisco"

    switch len(args) {
    case 3:
        *result = args[2]
    default:
        *result = cityDefault
    }
}

我通常使用this package来解析所有应用中的命令行参数。我将按如下方式构建我的代码（测试未显示，但它们通常遵循上面显示的测试要点）：

<强> main.go

package main

import (
    "log"
    "testing"
)

// TestParseFlags - test our command line flags
func TestParseFlags(t *testing.T) {
    var parseFlagsTests = []struct {
        flags    []string // input flags to the command line
        expected string   // expected
    }{
        {[]string{"/fake/loc/main"}, "San Francisco"},
        {[]string{"/fake/loc/main", "-c", "Los Angeles"}, "Los Angeles"},
        {[]string{"/fake/loc/main", "--city", "Los Angeles"}, "Los Angeles"},
    }

    for _, tt := range parseFlagsTests {
        var output string
        parseFlags(&output, tt.flags)
        if output != tt.expected {
            t.Errorf("expected: %s, actual: %s", tt.expected, output)
        }
    }
}

<强> /myDir/cli.go

package main

import (
    "log"
    "os"

    "myDir/cli"
)

func main() {
    // Grab the user inputed CLI flags
    cliFlags := cli.FlagsStruct{}
    cliErr := cli.StartCLI(&cliFlags, os.Args)
    if cliErr != nil {
        log.Println("Error grabbing command line args")
        log.Fatal(cliErr)
    }

    // Do stuff ...
}

Answer 2

test "$(./myapp -c "Los Angeles")" = "Los Angeles"怎么样同样的 - 城市。这与Go无关，只需让您的集成测试套件进行测试即可。

你如何测试golang命令行输出

2 个答案: