src/chromiumos/tast/common/genparams/params_test.go

// Copyright 2020 The Chromium OS Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

package genparams

import (
	"fmt"
	"io/ioutil"
	"os"
	"testing"

	"github.com/google/go-cmp/cmp"
	"github.com/kylelemons/godebug/diff"

	"chromiumos/tast/testutil"
)

// fakeTestingT is a fake implementation of TestingT.
// The zero value of fakeTestingT is ready to use.
type fakeTestingT struct {
	// Errors is a list of error messages reported so far.
	Errors []string
}

func (t *fakeTestingT) Helper() {}

func (t *fakeTestingT) Logf(format string, args ...interface{}) {}

func (t *fakeTestingT) Errorf(format string, args ...interface{}) {
	t.Errors = append(t.Errors, fmt.Sprintf(format, args...))
}

func (t *fakeTestingT) Fatalf(format string, args ...interface{}) {
	t.Errorf(format, args...)
	panic("fakeTestingT.Fatalf called")
}

// callEnsure is a helper function to call Ensure.
// It calls Ensure twice, without TAST_GENERATE_UPDATE and with
// TAST_GENERATE_UPDATE. It returns errors reported from the first call and
// generated code from the second call.
func callEnsure(t *testing.T, code, params string) (errors []string, newCode string) {
	// Create a temporary dir and chdir to it to make error messages deterministic.
	wd, err := os.Getwd()
	if err != nil {
		t.Fatal(err)
	}
	td := testutil.TempDir(t)
	defer os.RemoveAll(td)
	os.Chdir(td)
	defer os.Chdir(wd)

	const filename = "code.go"
	if err := testutil.WriteFiles(td, map[string]string{
		filename: code,
	}); err != nil {
		t.Fatal(t)
	}

	origEnv := os.Getenv(envName)
	defer os.Setenv(envName, origEnv)

	var ft0 fakeTestingT
	// Return errors even if ft0.Fatalf is called.
	defer func() {
		if recover() != nil {
			errors = ft0.Errors
		}
	}()

	// First, call Ensure in the check mode.
	os.Setenv(envName, "")
	Ensure(&ft0, filename, params)

	// Second, call Ensure in the update mode.
	var ft1 fakeTestingT
	os.Setenv(envName, "1")
	Ensure(&ft1, filename, params)
	if len(ft1.Errors) > 0 {
		t.Errorf("Ensure failed: %v", ft1.Errors)
	}

	newBytes, err := ioutil.ReadFile(filename)
	if err != nil {
		t.Fatal(err)
	}
	return ft0.Errors, string(newBytes)
}

const (
	testCode = `package example

import "chromiumos/tast/testing"

func init() {
	testing.AddTest(&testing.Test{
		Name: "Test",
		Params: []testing.Param{
			// Parameters generated by params_test.go. DO NOT EDIT.
			{Name: "a", Val: 1},
			{Name: "b", Val: 2},
		},
	})
}
`
	testParams = `{Name: "a", Val: 1},
{Name: "b", Val: 2},
`
)

func TestEnsureNoChange(t *testing.T) {
	errors, newCode := callEnsure(t, testCode, testParams)
	if diff := cmp.Diff(errors, []string(nil)); diff != "" {
		t.Errorf("Errors mismatch (-got +want):\n%s", diff)
	}
	if diff := diff.Diff(newCode, testCode); diff != "" {
		t.Errorf("Generated code mismatch (-got +want):\n%s", diff)
	}
}

func TestEnsureChange(t *testing.T) {
	const oldCode = `package example

import "chromiumos/tast/testing"

func init() {
	testing.AddTest(&testing.Test{
		Name: "Test",
		Params: []testing.Param{
			{Name: "x", Val: 28},
		},
	})
}
`
	errors, newCode := callEnsure(t, oldCode, testParams)
	wantErrors := []string{
		`code.go: Params is stale; run the following command to update:
TAST_GENERATE_UPDATE=1 ~/trunk/src/platform/tast/tools/go.sh test -count=1 chromiumos/tast/common/genparams`,
	}
	if diff := cmp.Diff(errors, wantErrors); diff != "" {
		t.Errorf("Errors mismatch (-got +want):\n%s", diff)
	}
	if diff := diff.Diff(newCode, testCode); diff != "" {
		t.Errorf("Generated code mismatch (-got +want):\n%s", diff)
	}
}

func TestEnsureMissingParams(t *testing.T) {
	const oldCode = `package example

import "chromiumos/tast/testing"

func init() {
	testing.AddTest(&testing.Test{
		Name: "Test",
	})
}
`
	errors, newCode := callEnsure(t, oldCode, testParams)
	wantErrors := []string{
		`code.go: Params is stale; run the following command to update:
TAST_GENERATE_UPDATE=1 ~/trunk/src/platform/tast/tools/go.sh test -count=1 chromiumos/tast/common/genparams`,
	}
	if diff := cmp.Diff(errors, wantErrors); diff != "" {
		t.Errorf("Errors mismatch (-got +want):\n%s", diff)
	}
	if diff := diff.Diff(newCode, testCode); diff != "" {
		t.Errorf("Generated code mismatch (-got +want):\n%s", diff)
	}
}

func TestEnsureNoRegistration(t *testing.T) {
	const oldCode = `package example

func init() {
	setUpSomething()
}
`
	errors, _ := callEnsure(t, oldCode, testParams)
	wantErrors := []string{
		"code.go: found 0 testing.AddTest calls; want 1",
	}
	if diff := cmp.Diff(errors, wantErrors); diff != "" {
		t.Errorf("Errors mismatch (-got +want):\n%s", diff)
	}
}

func TestEnsureDuplicatedRegistration(t *testing.T) {
	const oldCode = `package example

func init() {
	testing.AddTest(&testing.Test{
		Name: "Test1",
	})
	testing.AddTest(&testing.Test{
		Name: "Test2",
	})
}
`
	errors, _ := callEnsure(t, oldCode, testParams)
	wantErrors := []string{
		"code.go: found 2 testing.AddTest calls; want 1",
	}
	if diff := cmp.Diff(errors, wantErrors); diff != "" {
		t.Errorf("Errors mismatch (-got +want):\n%s", diff)
	}
}

func TestEnsureTestingAlias(t *testing.T) {
	const oldCode = `package example

import mytesting "chromiumos/tast/testing"

func init() {
	mytesting.AddTest(&mytesting.Test{
		Name: "Test",
	})
}
`
	errors, _ := callEnsure(t, oldCode, testParams)
	wantErrors := []string{
		"chromiumos/tast/testing must be imported without alias",
	}
	if diff := cmp.Diff(errors, wantErrors); diff != "" {
		t.Errorf("Errors mismatch (-got +want):\n%s", diff)
	}
}