go/analysis/unitchecker/unitchecker_test.go

// Copyright 2018 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

// +build go1.12

package unitchecker_test

// This test depends on features such as
// go vet's support for vetx files (1.11) and
// the (*os.ProcessState).ExitCode method (1.12).

import (
	"flag"
	"os"
	"os/exec"
	"runtime"
	"strings"
	"testing"

	"golang.org/x/tools/go/analysis/analysistest"
	"golang.org/x/tools/go/analysis/passes/findcall"
	"golang.org/x/tools/go/analysis/passes/printf"
	"golang.org/x/tools/go/analysis/unitchecker"
)

func TestMain(m *testing.M) {
	if os.Getenv("UNITCHECKER_CHILD") == "1" {
		// child process
		main()
		panic("unreachable")
	}

	// test
	flag.Parse()
	os.Exit(m.Run())
}

func main() {
	unitchecker.Main(
		findcall.Analyzer,
		printf.Analyzer,
	)
}

// This is a very basic integration test of modular
// analysis with facts using unitchecker under "go vet".
// It fork/execs the main function above.
func TestIntegration(t *testing.T) {
	if runtime.GOOS != "linux" {
		t.Skipf("skipping fork/exec test on this platform")
	}

	testdata := analysistest.TestData()

	const wantA = `# a
testdata/src/a/a.go:4:11: call of MyFunc123(...)
`
	const wantB = `# b
testdata/src/b/b.go:6:13: call of MyFunc123(...)
testdata/src/b/b.go:7:11: call of MyFunc123(...)
`
	const wantAJSON = `# a
{
	"a": {
		"findcall": [
			{
				"posn": "$GOPATH/src/a/a.go:4:11",
				"message": "call of MyFunc123(...)"
			}
		]
	}
}
`

	for _, test := range []struct {
		args     string
		wantOut  string
		wantExit int
	}{
		{args: "a", wantOut: wantA, wantExit: 2},
		{args: "b", wantOut: wantB, wantExit: 2},
		{args: "a b", wantOut: wantA + wantB, wantExit: 2},
		{args: "-json a", wantOut: wantAJSON, wantExit: 0},
		{args: "-c=0 a", wantOut: wantA + "4		MyFunc123()\n", wantExit: 2},
	} {
		cmd := exec.Command("go", "vet", "-vettool="+os.Args[0], "-findcall.name=MyFunc123")
		cmd.Args = append(cmd.Args, strings.Fields(test.args)...)
		cmd.Env = append(os.Environ(),
			"UNITCHECKER_CHILD=1",
			"GOPATH="+testdata,
		)

		out, err := cmd.CombinedOutput()
		exitcode := 0
		if exitErr, ok := err.(*exec.ExitError); ok {
			exitcode = exitErr.ExitCode()
		}
		if exitcode != test.wantExit {
			t.Errorf("%s: got exit code %d, want %d", test.args, exitcode, test.wantExit)
		}
		got := strings.Replace(string(out), testdata, "$GOPATH", -1)

		if got != test.wantOut {
			t.Errorf("%s: got <<%s>>, want <<%s>>", test.args, got, test.wantOut)
		}
	}
}