ci_test.go

package main

import (
	"os"
	"reflect"
	"testing"
)

func TestCircleci(t *testing.T) {
	envs := []string{
		"CIRCLE_SHA1",
		"CIRCLE_BUILD_URL",
		"CIRCLE_PULL_REQUEST",
		"CI_PULL_REQUEST",
		"CIRCLE_PR_NUMBER",
	}
	saveEnvs := make(map[string]string)
	for _, key := range envs {
		saveEnvs[key] = os.Getenv(key)
		os.Unsetenv(key)
	}
	defer func() {
		for key, value := range saveEnvs {
			os.Setenv(key, value)
		}
	}()

	testCases := []struct {
		fn func()
		ci CI
		ok bool
	}{
		{
			fn: func() {
				os.Setenv("CIRCLE_SHA1", "abcdefg")
				os.Setenv("CIRCLE_BUILD_URL", "https://circleci.com/gh/owner/repo/1234")
				os.Setenv("CIRCLE_PULL_REQUEST", "")
				os.Setenv("CI_PULL_REQUEST", "")
				os.Setenv("CIRCLE_PR_NUMBER", "")
			},
			ci: CI{
				PR: PullRequest{
					Revision: "abcdefg",
					Number:   0,
				},
				URL: "https://circleci.com/gh/owner/repo/1234",
			},
			ok: true,
		},
		{
			fn: func() {
				os.Setenv("CIRCLE_SHA1", "abcdefg")
				os.Setenv("CIRCLE_BUILD_URL", "https://circleci.com/gh/owner/repo/1234")
				os.Setenv("CIRCLE_PULL_REQUEST", "https://github.com/owner/repo/pull/1")
				os.Setenv("CI_PULL_REQUEST", "")
				os.Setenv("CIRCLE_PR_NUMBER", "")
			},
			ci: CI{
				PR: PullRequest{
					Revision: "abcdefg",
					Number:   1,
				},
				URL: "https://circleci.com/gh/owner/repo/1234",
			},
			ok: true,
		},
		{
			fn: func() {
				os.Setenv("CIRCLE_SHA1", "abcdefg")
				os.Setenv("CIRCLE_BUILD_URL", "https://circleci.com/gh/owner/repo/1234")
				os.Setenv("CIRCLE_PULL_REQUEST", "")
				os.Setenv("CI_PULL_REQUEST", "2")
				os.Setenv("CIRCLE_PR_NUMBER", "")
			},
			ci: CI{
				PR: PullRequest{
					Revision: "abcdefg",
					Number:   2,
				},
				URL: "https://circleci.com/gh/owner/repo/1234",
			},
			ok: true,
		},
		{
			fn: func() {
				os.Setenv("CIRCLE_SHA1", "abcdefg")
				os.Setenv("CIRCLE_BUILD_URL", "https://circleci.com/gh/owner/repo/1234")
				os.Setenv("CIRCLE_PULL_REQUEST", "")
				os.Setenv("CI_PULL_REQUEST", "")
				os.Setenv("CIRCLE_PR_NUMBER", "3")
			},
			ci: CI{
				PR: PullRequest{
					Revision: "abcdefg",
					Number:   3,
				},
				URL: "https://circleci.com/gh/owner/repo/1234",
			},
			ok: true,
		},
		{
			fn: func() {
				os.Setenv("CIRCLE_SHA1", "")
				os.Setenv("CIRCLE_BUILD_URL", "https://circleci.com/gh/owner/repo/1234")
				os.Setenv("CIRCLE_PULL_REQUEST", "")
				os.Setenv("CI_PULL_REQUEST", "")
				os.Setenv("CIRCLE_PR_NUMBER", "")
			},
			ci: CI{
				PR: PullRequest{
					Revision: "",
					Number:   0,
				},
				URL: "https://circleci.com/gh/owner/repo/1234",
			},
			ok: true,
		},
		{
			fn: func() {
				os.Setenv("CIRCLE_SHA1", "")
				os.Setenv("CIRCLE_BUILD_URL", "https://circleci.com/gh/owner/repo/1234")
				os.Setenv("CIRCLE_PULL_REQUEST", "abcdefg")
				os.Setenv("CI_PULL_REQUEST", "")
				os.Setenv("CIRCLE_PR_NUMBER", "")
			},
			ci: CI{
				PR: PullRequest{
					Revision: "",
					Number:   0,
				},
				URL: "https://circleci.com/gh/owner/repo/1234",
			},
			ok: false,
		},
	}

	for _, testCase := range testCases {
		testCase.fn()
		ci, err := circleci()
		if !reflect.DeepEqual(ci, testCase.ci) {
			t.Errorf("got %q but want %q", ci, testCase.ci)
		}
		if (err == nil) != testCase.ok {
			t.Errorf("got error %q", err)
		}
	}
}

func TestTravisCI(t *testing.T) {
	envs := []string{
		"TRAVIS_PULL_REQUEST_SHA",
		"TRAVIS_PULL_REQUEST",
		"TRAVIS_COMMIT",
	}
	saveEnvs := make(map[string]string)
	for _, key := range envs {
		saveEnvs[key] = os.Getenv(key)
		os.Unsetenv(key)
	}
	defer func() {
		for key, value := range saveEnvs {
			os.Setenv(key, value)
		}
	}()

	// https://docs.travis-ci.com/user/environment-variables/
	testCases := []struct {
		fn func()
		ci CI
		ok bool
	}{
		{
			fn: func() {
				os.Setenv("TRAVIS_PULL_REQUEST_SHA", "abcdefg")
				os.Setenv("TRAVIS_PULL_REQUEST", "1")
				os.Setenv("TRAVIS_COMMIT", "hijklmn")
			},
			ci: CI{
				PR: PullRequest{
					Revision: "abcdefg",
					Number:   1,
				},
				URL: "",
			},
			ok: true,
		},
		{
			fn: func() {
				os.Setenv("TRAVIS_PULL_REQUEST_SHA", "abcdefg")
				os.Setenv("TRAVIS_PULL_REQUEST", "false")
				os.Setenv("TRAVIS_COMMIT", "hijklmn")
			},
			ci: CI{
				PR: PullRequest{
					Revision: "hijklmn",
					Number:   0,
				},
				URL: "",
			},
			ok: true,
		},
	}

	for _, testCase := range testCases {
		testCase.fn()
		ci, err := travisci()
		if !reflect.DeepEqual(ci, testCase.ci) {
			t.Errorf("got %q but want %q", ci, testCase.ci)
		}
		if (err == nil) != testCase.ok {
			t.Errorf("got error %q", err)
		}
	}
}

func TestTeamCityCI(t *testing.T) {
	envs := []string{
		"BUILD_VCS_NUMBER",
		"BUILD_NUMBER",
	}
	saveEnvs := make(map[string]string)
	for _, key := range envs {
		saveEnvs[key] = os.Getenv(key)
		os.Unsetenv(key)
	}
	defer func() {
		for key, value := range saveEnvs {
			os.Setenv(key, value)
		}
	}()

	// https://confluence.jetbrains.com/display/TCD18/Predefined+Build+Parameters
	testCases := []struct {
		fn func()
		ci CI
		ok bool
	}{
		{
			fn: func() {
				os.Setenv("BUILD_VCS_NUMBER", "fafef5adb5b9c39244027c8f16f7c3aa7e352b2e")
				os.Setenv("BUILD_NUMBER", "123")
			},
			ci: CI{
				PR: PullRequest{
					Revision: "fafef5adb5b9c39244027c8f16f7c3aa7e352b2e",
					Number:   123,
				},
				URL: "",
			},
			ok: true,
		},
		{
			fn: func() {
				os.Setenv("BUILD_VCS_NUMBER", "abcdefg")
				os.Setenv("BUILD_NUMBER", "false")
			},
			ci: CI{
				PR: PullRequest{
					Revision: "abcdefg",
					Number:   0,
				},
				URL: "",
			},
			ok: false,
		},
	}

	for _, testCase := range testCases {
		testCase.fn()
		ci, err := teamcity()
		if !reflect.DeepEqual(ci, testCase.ci) {
			t.Errorf("got %q but want %q", ci, testCase.ci)
		}
		if (err == nil) != testCase.ok {
			t.Errorf("got error %q", err)
		}
	}
}

func TestCodeBuild(t *testing.T) {
	envs := []string{
		"CODEBUILD_RESOLVED_SOURCE_VERSION",
		"CODEBUILD_SOURCE_VERSION",
		"CODEBUILD_BUILD_URL",
	}
	saveEnvs := make(map[string]string)
	for _, key := range envs {
		saveEnvs[key] = os.Getenv(key)
		os.Unsetenv(key)
	}
	defer func() {
		for key, value := range saveEnvs {
			os.Setenv(key, value)
		}
	}()

	// https://docs.aws.amazon.com/codebuild/latest/userguide/build-env-ref.html
	testCases := []struct {
		fn func()
		ci CI
		ok bool
	}{
		{
			fn: func() {
				os.Setenv("CODEBUILD_RESOLVED_SOURCE_VERSION", "abcdefg")
				os.Setenv("CODEBUILD_SOURCE_VERSION", "pr/123")
				os.Setenv("CODEBUILD_BUILD_URL", "https://ap-northeast-1.console.aws.amazon.com/codebuild/home?region=ap-northeast-1#/builds/test:f2ae4314-c2d6-4db6-83c2-eacbab1517b7/view/new")
			},
			ci: CI{
				PR: PullRequest{
					Revision: "abcdefg",
					Number:   123,
				},
				URL: "https://ap-northeast-1.console.aws.amazon.com/codebuild/home?region=ap-northeast-1#/builds/test:f2ae4314-c2d6-4db6-83c2-eacbab1517b7/view/new",
			},
			ok: true,
		},
		{
			fn: func() {
				os.Setenv("CODEBUILD_RESOLVED_SOURCE_VERSION", "abcdefg")
				os.Setenv("CODEBUILD_SOURCE_VERSION", "pr/1")
				os.Setenv("CODEBUILD_BUILD_URL", "https://ap-northeast-1.console.aws.amazon.com/codebuild/home?region=ap-northeast-1#/builds/test:f2ae4314-c2d6-4db6-83c2-eacbab1517b7/view/new")
			},
			ci: CI{
				PR: PullRequest{
					Revision: "abcdefg",
					Number:   1,
				},
				URL: "https://ap-northeast-1.console.aws.amazon.com/codebuild/home?region=ap-northeast-1#/builds/test:f2ae4314-c2d6-4db6-83c2-eacbab1517b7/view/new",
			},
			ok: true,
		},
		{
			fn: func() {
				os.Setenv("CODEBUILD_RESOLVED_SOURCE_VERSION", "")
				os.Setenv("CODEBUILD_SOURCE_VERSION", "")
				os.Setenv("CODEBUILD_BUILD_URL", "https://ap-northeast-1.console.aws.amazon.com/codebuild/home?region=ap-northeast-1#/builds/test:f2ae4314-c2d6-4db6-83c2-eacbab1517b7/view/new")
			},
			ci: CI{
				PR: PullRequest{
					Revision: "",
					Number:   0,
				},
				URL: "https://ap-northeast-1.console.aws.amazon.com/codebuild/home?region=ap-northeast-1#/builds/test:f2ae4314-c2d6-4db6-83c2-eacbab1517b7/view/new",
			},
			ok: true,
		},
		{
			fn: func() {
				os.Setenv("CODEBUILD_RESOLVED_SOURCE_VERSION", "")
				os.Setenv("CODEBUILD_SOURCE_VERSION", "pr/abc")
				os.Setenv("CODEBUILD_BUILD_URL", "https://ap-northeast-1.console.aws.amazon.com/codebuild/home?region=ap-northeast-1#/builds/test:f2ae4314-c2d6-4db6-83c2-eacbab1517b7/view/new")
			},
			ci: CI{
				PR: PullRequest{
					Revision: "",
					Number:   0,
				},
				URL: "https://ap-northeast-1.console.aws.amazon.com/codebuild/home?region=ap-northeast-1#/builds/test:f2ae4314-c2d6-4db6-83c2-eacbab1517b7/view/new",
			},
			ok: false,
		},
		{
			fn: func() {
				os.Setenv("CODEBUILD_RESOLVED_SOURCE_VERSION", "")
				os.Setenv("CODEBUILD_SOURCE_VERSION", "f3008ac30d28ac38ae2533c2b153f00041661f22")
				os.Setenv("CODEBUILD_BUILD_URL", "https://ap-northeast-1.console.aws.amazon.com/codebuild/home?region=ap-northeast-1#/builds/test:f2ae4314-c2d6-4db6-83c2-eacbab1517b7/view/new")
			},
			ci: CI{
				PR: PullRequest{
					Revision: "",
					Number:   0,
				},
				URL: "https://ap-northeast-1.console.aws.amazon.com/codebuild/home?region=ap-northeast-1#/builds/test:f2ae4314-c2d6-4db6-83c2-eacbab1517b7/view/new",
			},
			ok: true,
		},
	}

	for _, testCase := range testCases {
		testCase.fn()
		ci, err := codebuild()
		if !reflect.DeepEqual(ci, testCase.ci) {
			t.Errorf("got %q but want %q", ci, testCase.ci)
		}
		if (err == nil) != testCase.ok {
			t.Errorf("got error %q", err)
		}
	}
}

func TestDrone(t *testing.T) {
	envs := []string{
		"DRONE_COMMIT_SHA",
		"DRONE_PULL_REQUEST",
	}
	saveEnvs := make(map[string]string)
	for _, key := range envs {
		saveEnvs[key] = os.Getenv(key)
		os.Unsetenv(key)
	}
	defer func() {
		for key, value := range saveEnvs {
			os.Setenv(key, value)
		}
	}()

	// https://docs.drone.io/reference/environ/
	testCases := []struct {
		fn func()
		ci CI
		ok bool
	}{
		{
			fn: func() {
				os.Setenv("DRONE_COMMIT_SHA", "abcdefg")
				os.Setenv("DRONE_PULL_REQUEST", "1")
				os.Setenv("DRONE_BUILD_LINK", "https://cloud.drone.io/owner/repo/1")
			},
			ci: CI{
				PR: PullRequest{
					Revision: "abcdefg",
					Number:   1,
				},
				URL: "https://cloud.drone.io/owner/repo/1",
			},
			ok: true,
		},
		{
			fn: func() {
				os.Setenv("DRONE_COMMIT_SHA", "abcdefg")
				os.Setenv("DRONE_PULL_REQUEST", "")
				os.Setenv("DRONE_BUILD_LINK", "https://cloud.drone.io/owner/repo/1")
			},
			ci: CI{
				PR: PullRequest{
					Revision: "abcdefg",
					Number:   0,
				},
				URL: "https://cloud.drone.io/owner/repo/1",
			},
			ok: true,
		},
		{
			fn: func() {
				os.Setenv("DRONE_COMMIT_SHA", "abcdefg")
				os.Setenv("DRONE_PULL_REQUEST", "abc")
				os.Setenv("DRONE_BUILD_LINK", "https://cloud.drone.io/owner/repo/1")
			},
			ci: CI{
				PR: PullRequest{
					Revision: "abcdefg",
					Number:   0,
				},
				URL: "https://cloud.drone.io/owner/repo/1",
			},
			ok: false,
		},
	}

	for _, testCase := range testCases {
		testCase.fn()
		ci, err := drone()
		if !reflect.DeepEqual(ci, testCase.ci) {
			t.Errorf("got %q but want %q", ci, testCase.ci)
		}
		if (err == nil) != testCase.ok {
			t.Errorf("got error %q", err)
		}
	}
}

func TestJenkins(t *testing.T) {
	envs := []string{
		"GIT_COMMIT",
		"BUILD_URL",
		"PULL_REQUEST_NUMBER",
		"PULL_REQUEST_URL",
	}
	saveEnvs := make(map[string]string)
	for _, key := range envs {
		saveEnvs[key] = os.Getenv(key)
		os.Unsetenv(key)
	}
	defer func() {
		for key, value := range saveEnvs {
			os.Setenv(key, value)
		}
	}()

	// https://wiki.jenkins.io/display/JENKINS/Building+a+software+project#Buildingasoftwareproject-belowJenkinsSetEnvironmentVariables
	testCases := []struct {
		fn func()
		ci CI
		ok bool
	}{
		{
			fn: func() {
				os.Setenv("GIT_COMMIT", "abcdefg")
				os.Setenv("PULL_REQUEST_NUMBER", "123")
				os.Setenv("BUILD_URL", "http://jenkins.example.com/jenkins/job/test-job/1")
			},
			ci: CI{
				PR: PullRequest{
					Revision: "abcdefg",
					Number:   123,
				},
				URL: "http://jenkins.example.com/jenkins/job/test-job/1",
			},
			ok: true,
		},
		{
			fn: func() {
				os.Setenv("GIT_COMMIT", "abcdefg")
				os.Setenv("PULL_REQUEST_NUMBER", "")
				os.Setenv("PULL_REQUEST_URL", "https://github.com/owner/repo/pull/1111")
				os.Setenv("BUILD_URL", "http://jenkins.example.com/jenkins/job/test-job/123")
			},
			ci: CI{
				PR: PullRequest{
					Revision: "abcdefg",
					Number:   1111,
				},
				URL: "http://jenkins.example.com/jenkins/job/test-job/123",
			},
			ok: true,
		},
		{
			fn: func() {
				os.Setenv("PULL_REQUEST_NUMBER", "")
				os.Setenv("PULL_REQUEST_URL", "")
				os.Setenv("GIT_COMMIT", "abcdefg")
				os.Setenv("BUILD_URL", "http://jenkins.example.com/jenkins/job/test-job/456")
			},
			ci: CI{
				PR: PullRequest{
					Revision: "abcdefg",
					Number:   0,
				},
				URL: "http://jenkins.example.com/jenkins/job/test-job/456",
			},
			ok: true,
		},
	}

	for _, testCase := range testCases {
		testCase.fn()
		ci, err := jenkins()
		if !reflect.DeepEqual(ci, testCase.ci) {
			t.Errorf("got %q but want %q", ci, testCase.ci)
		}
		if (err == nil) != testCase.ok {
			t.Errorf("got error %q", err)
		}
	}
}

func TestJenkinsGitLab(t *testing.T) {
	envs := []string{
		"BUILD_URL",
		"gitlabBefore",
		"gitlabMergeRequestIid",
	}
	saveEnvs := make(map[string]string)
	for _, key := range envs {
		saveEnvs[key] = os.Getenv(key)
		os.Unsetenv(key)
	}
	defer func() {
		for key, value := range saveEnvs {
			os.Setenv(key, value)
		}
	}()

	// https://wiki.jenkins.io/display/JENKINS/Building+a+software+project#Buildingasoftwareproject-belowJenkinsSetEnvironmentVariables
	testCases := []struct {
		fn func()
		ci CI
		ok bool
	}{
		{
			fn: func() {
				os.Setenv("gitlabBefore", "abcdefg")
				os.Setenv("gitlabMergeRequestIid", "123")
				os.Setenv("BUILD_URL", "http://jenkins.example.com/jenkins/job/test-job/1")
			},
			ci: CI{
				PR: PullRequest{
					Revision: "abcdefg",
					Number:   123,
				},
				URL: "http://jenkins.example.com/jenkins/job/test-job/1",
			},
			ok: true,
		},
		{
			fn: func() {
				os.Setenv("gitlabMergeRequestIid", "")
				os.Setenv("gitlabBefore", "abcdefg")
				os.Setenv("BUILD_URL", "http://jenkins.example.com/jenkins/job/test-job/456")
			},
			ci: CI{
				PR: PullRequest{
					Revision: "abcdefg",
					Number:   0,
				},
				URL: "http://jenkins.example.com/jenkins/job/test-job/456",
			},
			ok: true,
		},
	}

	for _, testCase := range testCases {
		testCase.fn()
		ci, err := jenkins()
		if !reflect.DeepEqual(ci, testCase.ci) {
			t.Errorf("got %q but want %q", ci, testCase.ci)
		}
		if (err == nil) != testCase.ok {
			t.Errorf("got error %q", err)
		}
	}
}

func TestGitLabCI(t *testing.T) {
	envs := []string{
		"CI_COMMIT_SHA",
		"CI_JOB_URL",
		"CI_MERGE_REQUEST_IID",
		"CI_MERGE_REQUEST_REF_PATH",
	}
	saveEnvs := make(map[string]string)
	for _, key := range envs {
		saveEnvs[key] = os.Getenv(key)
		os.Unsetenv(key)
	}
	defer func() {
		for key, value := range saveEnvs {
			os.Setenv(key, value)
		}
	}()

	// https://docs.gitlab.com/ee/ci/variables/README.html
	testCases := []struct {
		fn func()
		ci CI
		ok bool
	}{
		{
			fn: func() {
				os.Setenv("CI_COMMIT_SHA", "abcdefg")
				os.Setenv("CI_JOB_URL", "https://gitlab.com/owner/repo/-/jobs/111111111")
				os.Setenv("CI_MERGE_REQUEST_IID", "1")
				os.Setenv("CI_MERGE_REQUEST_REF_PATH", "refs/merge-requests/1/head")
			},
			ci: CI{
				PR: PullRequest{
					Revision: "abcdefg",
					Number:   1,
				},
				URL: "https://gitlab.com/owner/repo/-/jobs/111111111",
			},
			ok: true,
		},
		{
			fn: func() {
				os.Setenv("CI_COMMIT_SHA", "hijklmn")
				os.Setenv("CI_JOB_URL", "https://gitlab.com/owner/repo/-/jobs/222222222")
				os.Setenv("CI_MERGE_REQUEST_REF_PATH", "refs/merge-requests/123/head")
				os.Unsetenv("CI_MERGE_REQUEST_IID")
			},
			ci: CI{
				PR: PullRequest{
					Revision: "hijklmn",
					Number:   123,
				},
				URL: "https://gitlab.com/owner/repo/-/jobs/222222222",
			},
			ok: true,
		},
		{
			fn: func() {
				os.Setenv("CI_COMMIT_SHA", "hijklmn")
				os.Setenv("CI_JOB_URL", "https://gitlab.com/owner/repo/-/jobs/333333333")
				os.Unsetenv("CI_MERGE_REQUEST_IID")
				os.Unsetenv("CI_MERGE_REQUEST_REF_PATH")
			},
			ci: CI{
				PR: PullRequest{
					Revision: "hijklmn",
					Number:   0,
				},
				URL: "https://gitlab.com/owner/repo/-/jobs/333333333",
			},
			ok: true,
		},
	}

	for _, testCase := range testCases {
		testCase.fn()
		ci, err := gitlabci()
		if !reflect.DeepEqual(ci, testCase.ci) {
			t.Errorf("got %q but want %q", ci, testCase.ci)
		}
		if (err == nil) != testCase.ok {
			t.Errorf("got error %q", err)
		}
	}
}

func TestGitHubActions(t *testing.T) {
	envs := []string{
		"GITHUB_SHA",
		"GITHUB_REPOSITORY",
		"GITHUB_RUN_ID",
		"GITHUB_REF",
	}
	saveEnvs := make(map[string]string)
	for _, key := range envs {
		saveEnvs[key] = os.Getenv(key)
		os.Unsetenv(key)
	}
	defer func() {
		for key, value := range saveEnvs {
			os.Setenv(key, value)
		}
	}()

	// https://help.github.com/ja/actions/configuring-and-managing-workflows/using-environment-variables
	testCases := []struct {
		fn func()
		ci CI
		ok bool
	}{
		{
			fn: func() {
				os.Setenv("GITHUB_SHA", "abcdefg")
				os.Setenv("GITHUB_REPOSITORY", "mercari/tfnotify")
				os.Setenv("GITHUB_RUN_ID", "12345")
			},
			ci: CI{
				PR: PullRequest{
					Revision: "abcdefg",
					Number:   0,
				},
				URL: "https://github.com/mercari/tfnotify/actions/runs/12345",
			},
			ok: true,
		},
		{
			fn: func() {
				os.Setenv("GITHUB_SHA", "abcdefg")
				os.Setenv("GITHUB_REPOSITORY", "mercari/tfnotify")
				os.Setenv("GITHUB_RUN_ID", "12345")
				os.Setenv("GITHUB_REF", "refs/pull/123/merge")
			},
			ci: CI{
				PR: PullRequest{
					Revision: "abcdefg",
					Number:   123,
				},
				URL: "https://github.com/mercari/tfnotify/actions/runs/12345",
			},
			ok: true,
		},
	}

	for _, testCase := range testCases {
		testCase.fn()
		ci, err := githubActions()
		if !reflect.DeepEqual(ci, testCase.ci) {
			t.Errorf("got %q but want %q", ci, testCase.ci)
		}
		if (err == nil) != testCase.ok {
			t.Errorf("got error %q", err)
		}
	}
}

func TestCloudBuild(t *testing.T) {
	envs := []string{
		"COMMIT_SHA",
		"BUILD_ID",
		"PROJECT_ID",
		"_PR_NUMBER",
		"REGION",
	}
	saveEnvs := make(map[string]string)
	for _, key := range envs {
		saveEnvs[key] = os.Getenv(key)
		os.Unsetenv(key)
	}
	defer func() {
		for key, value := range saveEnvs {
			os.Setenv(key, value)
		}
	}()

	// https://cloud.google.com/cloud-build/docs/configuring-builds/substitute-variable-values
	testCases := []struct {
		fn func()
		ci CI
		ok bool
	}{
		{
			fn: func() {
				os.Setenv("COMMIT_SHA", "abcdefg")
				os.Setenv("BUILD_ID", "build-id")
				os.Setenv("PROJECT_ID", "gcp-project-id")
				os.Setenv("_PR_NUMBER", "123")
				os.Setenv("_REGION", "asia-northeast1")
			},
			ci: CI{
				PR: PullRequest{
					Revision: "abcdefg",
					Number:   123,
				},
				URL: "https://console.cloud.google.com/cloud-build/builds;region=asia-northeast1/build-id?project=gcp-project-id",
			},
			ok: true,
		},
		{
			fn: func() {
				os.Setenv("COMMIT_SHA", "")
				os.Setenv("BUILD_ID", "build-id")
				os.Setenv("PROJECT_ID", "gcp-project-id")
				os.Setenv("_PR_NUMBER", "")
				os.Setenv("_REGION", "")
			},
			ci: CI{
				PR: PullRequest{
					Revision: "",
					Number:   0,
				},
				URL: "https://console.cloud.google.com/cloud-build/builds;region=global/build-id?project=gcp-project-id",
			},
			ok: true,
		},
		{
			fn: func() {
				os.Setenv("COMMIT_SHA", "")
				os.Setenv("BUILD_ID", "build-id")
				os.Setenv("PROJECT_ID", "gcp-project-id")
				os.Setenv("_PR_NUMBER", "abc")
			},
			ci: CI{
				PR: PullRequest{
					Revision: "",
					Number:   0,
				},
				URL: "https://console.cloud.google.com/cloud-build/builds;region=global/build-id?project=gcp-project-id",
			},
			ok: false,
		},
	}

	for _, testCase := range testCases {
		testCase.fn()
		ci, err := cloudbuild()
		if !reflect.DeepEqual(ci, testCase.ci) {
			t.Errorf("got %q but want %q", ci, testCase.ci)
		}
		if (err == nil) != testCase.ok {
			t.Errorf("got error %q", err)
		}
	}
}