internal/postgres/insert_module_test.go - pkgsite - Git at Google

 // Copyright 2019 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.

 package postgres

 import (
 	"context"
 	"database/sql"
 	"errors"
 	"fmt"
 	"io/ioutil"
 	"path/filepath"
 	"strings"
 	"sync"
 	"testing"
 	"time"

 	"github.com/google/go-cmp/cmp"
 	"github.com/google/go-cmp/cmp/cmpopts"
 	"github.com/google/safehtml"
 	"golang.org/x/pkgsite/internal"
 	"golang.org/x/pkgsite/internal/database"
 	"golang.org/x/pkgsite/internal/derrors"
 	"golang.org/x/pkgsite/internal/licenses"
 	"golang.org/x/pkgsite/internal/source"
 	"golang.org/x/pkgsite/internal/stdlib"
 	"golang.org/x/pkgsite/internal/testing/sample"
 )

 func TestInsertModule(t *testing.T) {
 	ctx, cancel := context.WithTimeout(context.Background(), testTimeout*2)
 	defer cancel()

 	for _, test := range []struct {
 		name   string
 		module *internal.Module
 	}{
 		{
 			name:   "valid test",
 			module: sample.LegacyDefaultModule(),
 		},
 		{
 			name:   "valid test with internal package",
 			module: sample.LegacyModule(sample.ModulePath, sample.VersionString, "internal/foo"),
 		},
 		{
 			name: "valid test with go.mod missing",
 			module: func() *internal.Module {
 				m := sample.LegacyDefaultModule()
 				m.HasGoMod = false
 				return m
 			}(),
 		},
 		{
 			name:   "stdlib",
 			module: sample.LegacyModule("std", "v1.12.5", "context"),
 		},
 	} {
 		t.Run(test.name, func(t *testing.T) {
 			defer ResetTestDB(testDB, t)

 			if err := testDB.InsertModule(ctx, test.module); err != nil {
 				t.Fatal(err)
 			}
 			// Test that insertion of duplicate primary key won't fail.
 			if err := testDB.InsertModule(ctx, test.module); err != nil {
 				t.Fatal(err)
 			}
 			checkModule(ctx, t, test.module)
 		})
 	}
 }

 func checkModule(ctx context.Context, t *testing.T, want *internal.Module) {
 	got, err := testDB.GetModuleInfo(ctx, want.ModulePath, want.Version)
 	if err != nil {
 		t.Fatal(err)
 	}
 	if diff := cmp.Diff(want.ModuleInfo, *got, cmp.AllowUnexported(source.Info{})); diff != "" {
 		t.Fatalf("testDB.GetModuleInfo(%q, %q) mismatch (-want +got):\n%s", want.ModulePath, want.Version, diff)
 	}

 	for _, wantu := range want.Units {
 		got, err := testDB.GetUnit(ctx, &wantu.UnitMeta, internal.AllFields)
 		if err != nil {
 			t.Fatal(err)
 		}
 		// TODO(golang/go#38513): remove once we start displaying
 		// READMEs for directories instead of the top-level module.
 		wantu.Readme = &internal.Readme{
 			Filepath: sample.ReadmeFilePath,
 			Contents: sample.ReadmeContents,
 		}
 		wantu.LicenseContents = sample.Licenses
 		var subdirectories []*internal.PackageMeta
 		for _, u := range want.Units {
 			if u.IsPackage() && (strings.HasPrefix(u.Path, wantu.Path) ||
 				wantu.Path == stdlib.ModulePath) {
 				subdirectories = append(subdirectories, sample.PackageMeta(u.Path))
 			}
 		}
 		wantu.Subdirectories = subdirectories
 		opts := cmp.Options{
 			cmpopts.IgnoreFields(licenses.Metadata{}, "Coverage"),
 			cmp.AllowUnexported(source.Info{}, safehtml.HTML{}),
 		}
 		if diff := cmp.Diff(wantu, got, opts); diff != "" {
 			t.Errorf("mismatch (-want +got):\n%s", diff)
 		}
 	}
 }

 func TestInsertModuleLicenseCheck(t *testing.T) {
 	ctx, cancel := context.WithTimeout(context.Background(), testTimeout)
 	defer cancel()

 	for _, bypass := range []bool{false, true} {
 		t.Run(fmt.Sprintf("bypass=%t", bypass), func(t *testing.T) {
 			defer ResetTestDB(testDB, t)
 			var db *DB
 			if bypass {
 				db = NewBypassingLicenseCheck(testDB.db)
 			} else {
 				db = testDB
 			}
 			checkHasRedistData := func(readme string, doc safehtml.HTML, want bool) {
 				t.Helper()
 				if got := readme != ""; got != want {
 					t.Errorf("readme: got %t, want %t", got, want)
 				}
 				if got := doc.String() != ""; got != want {
 					t.Errorf("doc: got %t, want %t", got, want)
 				}
 			}

 			mod := sample.LegacyModule(sample.ModulePath, sample.VersionString, "")
 			checkHasRedistData(mod.Units[0].Readme.Contents, mod.Units[0].Documentation.HTML, true)
 			mod.IsRedistributable = false
 			mod.Units[0].IsRedistributable = false

 			if err := db.InsertModule(ctx, mod); err != nil {
 				t.Fatal(err)
 			}

 			// New model
 			pathInfo := &internal.UnitMeta{
 				Path:       mod.ModulePath,
 				ModulePath: mod.ModulePath,
 				Version:    mod.Version,
 			}
 			u, err := db.GetUnit(ctx, pathInfo, internal.AllFields)
 			if err != nil {
 				t.Fatal(err)
 			}
 			var readme string
 			if u.Readme != nil {
 				readme = u.Readme.Contents
 			}
 			var doc safehtml.HTML
 			if u.Documentation != nil {
 				doc = u.Documentation.HTML
 			}
 			checkHasRedistData(readme, doc, bypass)
 		})
 	}
 }

 func TestUpsertModule(t *testing.T) {
 	ctx, cancel := context.WithTimeout(context.Background(), testTimeout)
 	defer cancel()
 	m := sample.LegacyModule("upsert.org", "v1.2.3", "dir/p")

 	// Insert the module.
 	if err := testDB.InsertModule(ctx, m); err != nil {
 		t.Fatal(err)
 	}
 	// Change the module, and re-insert.
 	m.IsRedistributable = !m.IsRedistributable
 	m.Licenses[0].Contents = append(m.Licenses[0].Contents, " and more"...)
 	// TODO(golang/go#38513): uncomment line below once we start displaying
 	// READMEs for directories instead of the top-level module.
 	// m.Units[0].Readme.Contents += " and more"

 	if err := testDB.InsertModule(ctx, m); err != nil {
 		t.Fatal(err)
 	}
 	// The changes should have been saved.
 	checkModule(ctx, t, m)
 }

 func TestInsertModuleErrors(t *testing.T) {
 	ctx, cancel := context.WithTimeout(context.Background(), testTimeout*2)
 	defer cancel()

 	testCases := []struct {
 		name string

 		module *internal.Module

 		// identifiers to use for fetch
 		wantModulePath, wantVersion, wantPkgPath string

 		// error conditions
 		wantWriteErr error
 		wantReadErr  bool
 	}{
 		{
 			name:           "nil version write error",
 			wantModulePath: sample.ModulePath,
 			wantVersion:    sample.VersionString,
 			wantWriteErr:   derrors.DBModuleInsertInvalid,
 		},
 		{
 			name:           "nonexistent version",
 			module:         sample.LegacyDefaultModule(),
 			wantModulePath: sample.ModulePath,
 			wantVersion:    "v1.2.3",
 		},
 		{
 			name:           "nonexistent module",
 			module:         sample.LegacyDefaultModule(),
 			wantModulePath: "nonexistent_module_path",
 			wantVersion:    "v1.0.0",
 			wantPkgPath:    sample.PackagePath,
 		},
 		{
 			name:           "missing module path",
 			module:         sample.LegacyModule("", sample.VersionString),
 			wantVersion:    sample.VersionString,
 			wantModulePath: sample.ModulePath,
 			wantWriteErr:   derrors.DBModuleInsertInvalid,
 		},
 		{
 			name: "missing version",
 			module: func() *internal.Module {
 				m := sample.LegacyDefaultModule()
 				m.Version = ""
 				return m
 			}(),
 			wantVersion:    sample.VersionString,
 			wantModulePath: sample.ModulePath,
 			wantWriteErr:   derrors.DBModuleInsertInvalid,
 		},
 		{
 			name: "empty commit time",
 			module: func() *internal.Module {
 				v := sample.LegacyDefaultModule()
 				v.CommitTime = time.Time{}
 				return v
 			}(),
 			wantVersion:    sample.VersionString,
 			wantModulePath: sample.ModulePath,
 			wantWriteErr:   derrors.BadModule,
 		},
 	}

 	for _, tc := range testCases {
 		t.Run(tc.name, func(t *testing.T) {
 			defer ResetTestDB(testDB, t)
 			if err := testDB.InsertModule(ctx, tc.module); !errors.Is(err, tc.wantWriteErr) {
 				t.Errorf("error: %v, want write error: %v", err, tc.wantWriteErr)
 			}
 		})
 	}
 }

 func TestPostgres_ReadAndWriteModuleOtherColumns(t *testing.T) {
 	// Verify that InsertModule correctly populates the columns in the versions
 	// table that are not in the LegacyModuleInfo struct.
 	defer ResetTestDB(testDB, t)
 	ctx := context.Background()

 	type other struct {
 		sortVersion, seriesPath string
 	}

 	v := sample.LegacyModule("github.com/user/repo/path/v2", "v1.2.3-beta.4.a", sample.Suffix)
 	want := other{
 		sortVersion: "1,2,3,~beta,4,~a",
 		seriesPath:  "github.com/user/repo/path",
 	}

 	if err := testDB.InsertModule(ctx, v); err != nil {
 		t.Fatal(err)
 	}
 	query := `
 	SELECT
 		sort_version, series_path
 	FROM
 		modules
 	WHERE
 		module_path = $1 AND version = $2`
 	row := testDB.db.QueryRow(ctx, query, v.ModulePath, v.Version)
 	var got other
 	if err := row.Scan(&got.sortVersion, &got.seriesPath); err != nil {
 		t.Fatal(err)
 	}
 	if got != want {
 		t.Errorf("\ngot  %+v\nwant %+v", got, want)
 	}
 }

 func TestLatestVersion(t *testing.T) {
 	defer ResetTestDB(testDB, t)
 	ctx := context.Background()

 	for _, mod := range []struct {
 		version    string
 		modulePath string
 	}{
 		{
 			version:    "v1.5.2",
 			modulePath: sample.ModulePath,
 		},
 		{
 			version:    "v2.0.0+incompatible",
 			modulePath: sample.ModulePath,
 		},
 		{
 			version:    "v2.0.1",
 			modulePath: sample.ModulePath + "/v2",
 		},
 		{
 			version:    "v3.0.1-rc9.0.20200212222136-a4a89636720b",
 			modulePath: sample.ModulePath + "/v3",
 		},
 		{
 			version:    "v3.0.1-rc9",
 			modulePath: sample.ModulePath + "/v3",
 		},
 	} {
 		m := sample.LegacyDefaultModule()
 		m.Version = mod.version
 		m.ModulePath = mod.modulePath

 		if err := testDB.InsertModule(ctx, m); err != nil {
 			t.Fatal(err)
 		}
 	}

 	for _, tc := range []struct {
 		name        string
 		modulePath  string
 		wantVersion string
 	}{
 		{
 			name:        "test v1 version",
 			modulePath:  sample.ModulePath,
 			wantVersion: "v1.5.2",
 		},
 		{
 			name:        "test v2 version",
 			modulePath:  sample.ModulePath + "/v2",
 			wantVersion: "v2.0.1",
 		},
 		{
 			name:        "test v3 version - prefer prerelease over pseudo",
 			modulePath:  sample.ModulePath + "/v3",
 			wantVersion: "v3.0.1-rc9",
 		},
 	} {
 		t.Run(tc.name, func(t *testing.T) {
 			isLatest, err := isLatestVersion(ctx, testDB.db, tc.modulePath, tc.wantVersion)
 			if err != nil {
 				t.Fatal(err)
 			}
 			if !isLatest {
 				t.Errorf("%s is not the latest version", tc.wantVersion)
 			}
 		})
 	}
 }

 func TestLatestVersion_PreferIncompatibleOverPrerelease(t *testing.T) {
 	defer ResetTestDB(testDB, t)
 	ctx := context.Background()

 	for _, mod := range []struct {
 		version    string
 		modulePath string
 	}{
 		{
 			version:    "v0.0.0-20201007032633-0806396f153e",
 			modulePath: sample.ModulePath,
 		},
 		{
 			version:    "v2.0.0+incompatible",
 			modulePath: sample.ModulePath,
 		},
 	} {
 		m := sample.LegacyDefaultModule()
 		m.Version = mod.version
 		m.ModulePath = mod.modulePath

 		if err := testDB.InsertModule(ctx, m); err != nil {
 			t.Fatal(err)
 		}
 	}

 	for _, tc := range []struct {
 		modulePath string
 		want       string
 	}{
 		{
 			modulePath: sample.ModulePath,
 			want:       "v2.0.0+incompatible",
 		},
 	} {
 		isLatest, err := isLatestVersion(ctx, testDB.db, tc.modulePath, tc.want)
 		if err != nil {
 			t.Fatal(err)
 		}
 		if !isLatest {
 			t.Errorf("%s is not the latest version", tc.want)
 		}
 	}
 }

 func TestDeleteModule(t *testing.T) {
 	ctx, cancel := context.WithTimeout(context.Background(), testTimeout)
 	defer cancel()
 	defer ResetTestDB(testDB, t)

 	v := sample.LegacyDefaultModule()

 	if err := testDB.InsertModule(ctx, v); err != nil {
 		t.Fatal(err)
 	}
 	if _, err := testDB.GetModuleInfo(ctx, v.ModulePath, v.Version); err != nil {
 		t.Fatal(err)
 	}

 	vm := sample.DefaultVersionMap()
 	if err := testDB.UpsertVersionMap(ctx, vm); err != nil {
 		t.Fatal(err)
 	}
 	if _, err := testDB.GetVersionMap(ctx, v.ModulePath, v.Version); err != nil {
 		t.Fatal(err)
 	}

 	if err := testDB.DeleteModule(ctx, v.ModulePath, v.Version); err != nil {
 		t.Fatal(err)
 	}
 	if _, err := testDB.GetModuleInfo(ctx, v.ModulePath, v.Version); !errors.Is(err, derrors.NotFound) {
 		t.Errorf("got %v, want NotFound", err)
 	}

 	var x int
 	err := testDB.Underlying().QueryRow(ctx, "SELECT 1 FROM imports_unique WHERE from_module_path = $1",
 		v.ModulePath).Scan(&x)
 	if err != sql.ErrNoRows {
 		t.Errorf("imports_unique: got %v, want ErrNoRows", err)
 	}
 	err = testDB.Underlying().QueryRow(
 		ctx,
 		"SELECT 1 FROM version_map WHERE module_path = $1 AND resolved_version = $2",
 		v.ModulePath, v.Version).Scan(&x)
 	if err != sql.ErrNoRows {
 		t.Errorf("version_map: got %v, want ErrNoRows", err)
 	}
 }

 func TestPostgres_NewerAlternative(t *testing.T) {
 	// Verify that packages are not added to search_documents if the module has a newer
 	// alternative version.
 	ctx, cancel := context.WithTimeout(context.Background(), testTimeout)
 	defer cancel()
 	defer ResetTestDB(testDB, t)

 	const (
 		modulePath = "example.com/Mod"
 		altVersion = "v1.2.0"
 		okVersion  = "v1.0.0"
 	)

 	err := testDB.UpsertModuleVersionState(ctx, modulePath, altVersion, "appVersion", time.Now(),
 		derrors.ToStatus(derrors.AlternativeModule), "example.com/mod", derrors.AlternativeModule, nil)
 	if err != nil {
 		t.Fatal(err)
 	}
 	m := sample.LegacyModule(modulePath, okVersion, "p")
 	if err := testDB.InsertModule(ctx, m); err != nil {
 		t.Fatal(err)
 	}
 	if _, _, found := GetFromSearchDocuments(ctx, t, testDB, m.Packages()[0].Path); found {
 		t.Fatal("found package after inserting")
 	}
 }

 func TestMakeValidUnicode(t *testing.T) {
 	ctx, cancel := context.WithTimeout(context.Background(), testTimeout)
 	defer cancel()

 	defer ResetTestDB(testDB, t)

 	db := testDB.Underlying()

 	if _, err := db.Exec(ctx, `CREATE TABLE IF NOT EXISTS valid_unicode (contents text)`); err != nil {
 		t.Fatal(err)
 	}
 	defer db.Exec(ctx, `DROP TABLE valid_unicode`)

 	insert := func(s string) error {
 		_, err := db.Exec(ctx, `INSERT INTO valid_unicode VALUES($1)`, s)
 		return err
 	}

 	check := func(filename string, okRaw bool) {
 		data, err := ioutil.ReadFile(filepath.Join("testdata", filename))
 		if err != nil {
 			t.Fatal(err)
 		}
 		raw := string(data)
 		err = insert(raw)
 		if (err == nil) != okRaw {
 			t.Errorf("%s, raw: got %v, want error: %t", filename, err, okRaw)
 		}
 		if err := insert(makeValidUnicode(string(data))); err != nil {
 			t.Errorf("%s, after making valid: %v", filename, err)
 		}
 	}

 	check("final-nulls", false)
 	check("gin-gonic", true)
 	check("subchord", true)
 }

 func TestLock(t *testing.T) {
 	// Verify that two transactions cannot both hold the same lock, but that every one
 	// that wants the lock eventually gets it.
 	ctx, cancel := context.WithTimeout(context.Background(), testTimeout)
 	defer cancel()
 	defer ResetTestDB(testDB, t)

 	db := testDB.Underlying()

 	const n = 4
 	errc := make(chan error)
 	var (
 		mu       sync.Mutex
 		lockHeld bool
 		count    int
 	)

 	for i := 0; i < n; i++ {
 		go func() {
 			errc <- db.Transact(ctx, sql.LevelDefault, func(tx *database.DB) error {
 				if err := lock(ctx, tx, sample.ModulePath); err != nil {
 					return err
 				}

 				mu.Lock()
 				h := lockHeld
 				lockHeld = true
 				count++
 				mu.Unlock()
 				if h {
 					return errors.New("lock already held")
 				}
 				time.Sleep(50 * time.Millisecond)
 				mu.Lock()
 				lockHeld = false
 				mu.Unlock()
 				return nil
 			})
 		}()
 	}
 	for i := 0; i < n; i++ {
 		if err := <-errc; err != nil {
 			t.Fatal(err)
 		}
 	}
 	if count != n {
 		t.Errorf("got %d, want %d", count, n)
 	}
 }
	// Copyright 2019 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.

	package postgres

	import (
	"context"
	"database/sql"
	"errors"
	"fmt"
	"io/ioutil"
	"path/filepath"
	"strings"
	"sync"
	"testing"
	"time"

	"github.com/google/go-cmp/cmp"
	"github.com/google/go-cmp/cmp/cmpopts"
	"github.com/google/safehtml"
	"golang.org/x/pkgsite/internal"
	"golang.org/x/pkgsite/internal/database"
	"golang.org/x/pkgsite/internal/derrors"
	"golang.org/x/pkgsite/internal/licenses"
	"golang.org/x/pkgsite/internal/source"
	"golang.org/x/pkgsite/internal/stdlib"
	"golang.org/x/pkgsite/internal/testing/sample"
	)

	func TestInsertModule(t *testing.T) {
	ctx, cancel := context.WithTimeout(context.Background(), testTimeout*2)
	defer cancel()

	for _, test := range []struct {
	name string
	module *internal.Module
	}{
	{
	name: "valid test",
	module: sample.LegacyDefaultModule(),
	},
	{
	name: "valid test with internal package",
	module: sample.LegacyModule(sample.ModulePath, sample.VersionString, "internal/foo"),
	},
	{
	name: "valid test with go.mod missing",
	module: func() *internal.Module {
	m := sample.LegacyDefaultModule()
	m.HasGoMod = false
	return m
	}(),
	},
	{
	name: "stdlib",
	module: sample.LegacyModule("std", "v1.12.5", "context"),
	},
	} {
	t.Run(test.name, func(t *testing.T) {
	defer ResetTestDB(testDB, t)

	if err := testDB.InsertModule(ctx, test.module); err != nil {
	t.Fatal(err)
	}
	// Test that insertion of duplicate primary key won't fail.
	if err := testDB.InsertModule(ctx, test.module); err != nil {
	t.Fatal(err)
	}
	checkModule(ctx, t, test.module)
	})
	}
	}

	func checkModule(ctx context.Context, t testing.T, want internal.Module) {
	got, err := testDB.GetModuleInfo(ctx, want.ModulePath, want.Version)
	if err != nil {
	t.Fatal(err)
	}
	if diff := cmp.Diff(want.ModuleInfo, *got, cmp.AllowUnexported(source.Info{})); diff != "" {
	t.Fatalf("testDB.GetModuleInfo(%q, %q) mismatch (-want +got):\n%s", want.ModulePath, want.Version, diff)
	}

	for _, wantu := range want.Units {
	got, err := testDB.GetUnit(ctx, &wantu.UnitMeta, internal.AllFields)
	if err != nil {
	t.Fatal(err)
	}
	// TODO(golang/go#38513): remove once we start displaying
	// READMEs for directories instead of the top-level module.
	wantu.Readme = &internal.Readme{
	Filepath: sample.ReadmeFilePath,
	Contents: sample.ReadmeContents,
	}
	wantu.LicenseContents = sample.Licenses
	var subdirectories []*internal.PackageMeta
	for _, u := range want.Units {
	if u.IsPackage() && (strings.HasPrefix(u.Path, wantu.Path) \|\|
	wantu.Path == stdlib.ModulePath) {
	subdirectories = append(subdirectories, sample.PackageMeta(u.Path))
	}
	}
	wantu.Subdirectories = subdirectories
	opts := cmp.Options{
	cmpopts.IgnoreFields(licenses.Metadata{}, "Coverage"),
	cmp.AllowUnexported(source.Info{}, safehtml.HTML{}),
	}
	if diff := cmp.Diff(wantu, got, opts); diff != "" {
	t.Errorf("mismatch (-want +got):\n%s", diff)
	}
	}
	}

	func TestInsertModuleLicenseCheck(t *testing.T) {
	ctx, cancel := context.WithTimeout(context.Background(), testTimeout)
	defer cancel()

	for _, bypass := range []bool{false, true} {
	t.Run(fmt.Sprintf("bypass=%t", bypass), func(t *testing.T) {
	defer ResetTestDB(testDB, t)
	var db *DB
	if bypass {
	db = NewBypassingLicenseCheck(testDB.db)
	} else {
	db = testDB
	}
	checkHasRedistData := func(readme string, doc safehtml.HTML, want bool) {
	t.Helper()
	if got := readme != ""; got != want {
	t.Errorf("readme: got %t, want %t", got, want)
	}
	if got := doc.String() != ""; got != want {
	t.Errorf("doc: got %t, want %t", got, want)
	}
	}

	mod := sample.LegacyModule(sample.ModulePath, sample.VersionString, "")
	checkHasRedistData(mod.Units[0].Readme.Contents, mod.Units[0].Documentation.HTML, true)
	mod.IsRedistributable = false
	mod.Units[0].IsRedistributable = false

	if err := db.InsertModule(ctx, mod); err != nil {
	t.Fatal(err)
	}

	// New model
	pathInfo := &internal.UnitMeta{
	Path: mod.ModulePath,
	ModulePath: mod.ModulePath,
	Version: mod.Version,
	}
	u, err := db.GetUnit(ctx, pathInfo, internal.AllFields)
	if err != nil {
	t.Fatal(err)
	}
	var readme string
	if u.Readme != nil {
	readme = u.Readme.Contents
	}
	var doc safehtml.HTML
	if u.Documentation != nil {
	doc = u.Documentation.HTML
	}
	checkHasRedistData(readme, doc, bypass)
	})
	}
	}

	func TestUpsertModule(t *testing.T) {
	ctx, cancel := context.WithTimeout(context.Background(), testTimeout)
	defer cancel()
	m := sample.LegacyModule("upsert.org", "v1.2.3", "dir/p")

	// Insert the module.
	if err := testDB.InsertModule(ctx, m); err != nil {
	t.Fatal(err)
	}
	// Change the module, and re-insert.
	m.IsRedistributable = !m.IsRedistributable
	m.Licenses[0].Contents = append(m.Licenses[0].Contents, " and more"...)
	// TODO(golang/go#38513): uncomment line below once we start displaying
	// READMEs for directories instead of the top-level module.
	// m.Units[0].Readme.Contents += " and more"

	if err := testDB.InsertModule(ctx, m); err != nil {
	t.Fatal(err)
	}
	// The changes should have been saved.
	checkModule(ctx, t, m)
	}

	func TestInsertModuleErrors(t *testing.T) {
	ctx, cancel := context.WithTimeout(context.Background(), testTimeout*2)
	defer cancel()

	testCases := []struct {
	name string

	module *internal.Module

	// identifiers to use for fetch
	wantModulePath, wantVersion, wantPkgPath string

	// error conditions
	wantWriteErr error
	wantReadErr bool
	}{
	{
	name: "nil version write error",
	wantModulePath: sample.ModulePath,
	wantVersion: sample.VersionString,
	wantWriteErr: derrors.DBModuleInsertInvalid,
	},
	{
	name: "nonexistent version",
	module: sample.LegacyDefaultModule(),
	wantModulePath: sample.ModulePath,
	wantVersion: "v1.2.3",
	},
	{
	name: "nonexistent module",
	module: sample.LegacyDefaultModule(),
	wantModulePath: "nonexistent_module_path",
	wantVersion: "v1.0.0",
	wantPkgPath: sample.PackagePath,
	},
	{
	name: "missing module path",
	module: sample.LegacyModule("", sample.VersionString),
	wantVersion: sample.VersionString,
	wantModulePath: sample.ModulePath,
	wantWriteErr: derrors.DBModuleInsertInvalid,
	},
	{
	name: "missing version",
	module: func() *internal.Module {
	m := sample.LegacyDefaultModule()
	m.Version = ""
	return m
	}(),
	wantVersion: sample.VersionString,
	wantModulePath: sample.ModulePath,
	wantWriteErr: derrors.DBModuleInsertInvalid,
	},
	{
	name: "empty commit time",
	module: func() *internal.Module {
	v := sample.LegacyDefaultModule()
	v.CommitTime = time.Time{}
	return v
	}(),
	wantVersion: sample.VersionString,
	wantModulePath: sample.ModulePath,
	wantWriteErr: derrors.BadModule,
	},
	}

	for _, tc := range testCases {
	t.Run(tc.name, func(t *testing.T) {
	defer ResetTestDB(testDB, t)
	if err := testDB.InsertModule(ctx, tc.module); !errors.Is(err, tc.wantWriteErr) {
	t.Errorf("error: %v, want write error: %v", err, tc.wantWriteErr)
	}
	})
	}
	}

	func TestPostgres_ReadAndWriteModuleOtherColumns(t *testing.T) {
	// Verify that InsertModule correctly populates the columns in the versions
	// table that are not in the LegacyModuleInfo struct.
	defer ResetTestDB(testDB, t)
	ctx := context.Background()

	type other struct {
	sortVersion, seriesPath string
	}

	v := sample.LegacyModule("github.com/user/repo/path/v2", "v1.2.3-beta.4.a", sample.Suffix)
	want := other{
	sortVersion: "1,2,3,~beta,4,~a",
	seriesPath: "github.com/user/repo/path",
	}

	if err := testDB.InsertModule(ctx, v); err != nil {
	t.Fatal(err)
	}
	query := `
	SELECT
	sort_version, series_path
	FROM
	modules
	WHERE
	module_path = $1 AND version = $2`
	row := testDB.db.QueryRow(ctx, query, v.ModulePath, v.Version)
	var got other
	if err := row.Scan(&got.sortVersion, &got.seriesPath); err != nil {
	t.Fatal(err)
	}
	if got != want {
	t.Errorf("\ngot %+v\nwant %+v", got, want)
	}
	}

	func TestLatestVersion(t *testing.T) {
	defer ResetTestDB(testDB, t)
	ctx := context.Background()

	for _, mod := range []struct {
	version string
	modulePath string
	}{
	{
	version: "v1.5.2",
	modulePath: sample.ModulePath,
	},
	{
	version: "v2.0.0+incompatible",
	modulePath: sample.ModulePath,
	},
	{
	version: "v2.0.1",
	modulePath: sample.ModulePath + "/v2",
	},
	{
	version: "v3.0.1-rc9.0.20200212222136-a4a89636720b",
	modulePath: sample.ModulePath + "/v3",
	},
	{
	version: "v3.0.1-rc9",
	modulePath: sample.ModulePath + "/v3",
	},
	} {
	m := sample.LegacyDefaultModule()
	m.Version = mod.version
	m.ModulePath = mod.modulePath

	if err := testDB.InsertModule(ctx, m); err != nil {
	t.Fatal(err)
	}
	}

	for _, tc := range []struct {
	name string
	modulePath string
	wantVersion string
	}{
	{
	name: "test v1 version",
	modulePath: sample.ModulePath,
	wantVersion: "v1.5.2",
	},
	{
	name: "test v2 version",
	modulePath: sample.ModulePath + "/v2",
	wantVersion: "v2.0.1",
	},
	{
	name: "test v3 version - prefer prerelease over pseudo",
	modulePath: sample.ModulePath + "/v3",
	wantVersion: "v3.0.1-rc9",
	},
	} {
	t.Run(tc.name, func(t *testing.T) {
	isLatest, err := isLatestVersion(ctx, testDB.db, tc.modulePath, tc.wantVersion)
	if err != nil {
	t.Fatal(err)
	}
	if !isLatest {
	t.Errorf("%s is not the latest version", tc.wantVersion)
	}
	})
	}
	}

	func TestLatestVersion_PreferIncompatibleOverPrerelease(t *testing.T) {
	defer ResetTestDB(testDB, t)
	ctx := context.Background()

	for _, mod := range []struct {
	version string
	modulePath string
	}{
	{
	version: "v0.0.0-20201007032633-0806396f153e",
	modulePath: sample.ModulePath,
	},
	{
	version: "v2.0.0+incompatible",
	modulePath: sample.ModulePath,
	},
	} {
	m := sample.LegacyDefaultModule()
	m.Version = mod.version
	m.ModulePath = mod.modulePath

	if err := testDB.InsertModule(ctx, m); err != nil {
	t.Fatal(err)
	}
	}

	for _, tc := range []struct {
	modulePath string
	want string
	}{
	{
	modulePath: sample.ModulePath,
	want: "v2.0.0+incompatible",
	},
	} {
	isLatest, err := isLatestVersion(ctx, testDB.db, tc.modulePath, tc.want)
	if err != nil {
	t.Fatal(err)
	}
	if !isLatest {
	t.Errorf("%s is not the latest version", tc.want)
	}
	}
	}

	func TestDeleteModule(t *testing.T) {
	ctx, cancel := context.WithTimeout(context.Background(), testTimeout)
	defer cancel()
	defer ResetTestDB(testDB, t)

	v := sample.LegacyDefaultModule()

	if err := testDB.InsertModule(ctx, v); err != nil {
	t.Fatal(err)
	}
	if _, err := testDB.GetModuleInfo(ctx, v.ModulePath, v.Version); err != nil {
	t.Fatal(err)
	}

	vm := sample.DefaultVersionMap()
	if err := testDB.UpsertVersionMap(ctx, vm); err != nil {
	t.Fatal(err)
	}
	if _, err := testDB.GetVersionMap(ctx, v.ModulePath, v.Version); err != nil {
	t.Fatal(err)
	}

	if err := testDB.DeleteModule(ctx, v.ModulePath, v.Version); err != nil {
	t.Fatal(err)
	}
	if _, err := testDB.GetModuleInfo(ctx, v.ModulePath, v.Version); !errors.Is(err, derrors.NotFound) {
	t.Errorf("got %v, want NotFound", err)
	}

	var x int
	err := testDB.Underlying().QueryRow(ctx, "SELECT 1 FROM imports_unique WHERE from_module_path = $1",
	v.ModulePath).Scan(&x)
	if err != sql.ErrNoRows {
	t.Errorf("imports_unique: got %v, want ErrNoRows", err)
	}
	err = testDB.Underlying().QueryRow(
	ctx,
	"SELECT 1 FROM version_map WHERE module_path = $1 AND resolved_version = $2",
	v.ModulePath, v.Version).Scan(&x)
	if err != sql.ErrNoRows {
	t.Errorf("version_map: got %v, want ErrNoRows", err)
	}
	}

	func TestPostgres_NewerAlternative(t *testing.T) {
	// Verify that packages are not added to search_documents if the module has a newer
	// alternative version.
	ctx, cancel := context.WithTimeout(context.Background(), testTimeout)
	defer cancel()
	defer ResetTestDB(testDB, t)

	const (
	modulePath = "example.com/Mod"
	altVersion = "v1.2.0"
	okVersion = "v1.0.0"
	)

	err := testDB.UpsertModuleVersionState(ctx, modulePath, altVersion, "appVersion", time.Now(),
	derrors.ToStatus(derrors.AlternativeModule), "example.com/mod", derrors.AlternativeModule, nil)
	if err != nil {
	t.Fatal(err)
	}
	m := sample.LegacyModule(modulePath, okVersion, "p")
	if err := testDB.InsertModule(ctx, m); err != nil {
	t.Fatal(err)
	}
	if _, _, found := GetFromSearchDocuments(ctx, t, testDB, m.Packages()[0].Path); found {
	t.Fatal("found package after inserting")
	}
	}

	func TestMakeValidUnicode(t *testing.T) {
	ctx, cancel := context.WithTimeout(context.Background(), testTimeout)
	defer cancel()

	defer ResetTestDB(testDB, t)

	db := testDB.Underlying()

	if _, err := db.Exec(ctx, `CREATE TABLE IF NOT EXISTS valid_unicode (contents text)`); err != nil {
	t.Fatal(err)
	}
	defer db.Exec(ctx, `DROP TABLE valid_unicode`)

	insert := func(s string) error {
	_, err := db.Exec(ctx, `INSERT INTO valid_unicode VALUES($1)`, s)
	return err
	}

	check := func(filename string, okRaw bool) {
	data, err := ioutil.ReadFile(filepath.Join("testdata", filename))
	if err != nil {
	t.Fatal(err)
	}
	raw := string(data)
	err = insert(raw)
	if (err == nil) != okRaw {
	t.Errorf("%s, raw: got %v, want error: %t", filename, err, okRaw)
	}
	if err := insert(makeValidUnicode(string(data))); err != nil {
	t.Errorf("%s, after making valid: %v", filename, err)
	}
	}

	check("final-nulls", false)
	check("gin-gonic", true)
	check("subchord", true)
	}

	func TestLock(t *testing.T) {
	// Verify that two transactions cannot both hold the same lock, but that every one
	// that wants the lock eventually gets it.
	ctx, cancel := context.WithTimeout(context.Background(), testTimeout)
	defer cancel()
	defer ResetTestDB(testDB, t)

	db := testDB.Underlying()

	const n = 4
	errc := make(chan error)
	var (
	mu sync.Mutex
	lockHeld bool
	count int
	)

	for i := 0; i < n; i++ {
	go func() {
	errc <- db.Transact(ctx, sql.LevelDefault, func(tx *database.DB) error {
	if err := lock(ctx, tx, sample.ModulePath); err != nil {
	return err
	}

	mu.Lock()
	h := lockHeld
	lockHeld = true
	count++
	mu.Unlock()
	if h {
	return errors.New("lock already held")
	}
	time.Sleep(50 * time.Millisecond)
	mu.Lock()
	lockHeld = false
	mu.Unlock()
	return nil
	})
	}()
	}
	for i := 0; i < n; i++ {
	if err := <-errc; err != nil {
	t.Fatal(err)
	}
	}
	if count != n {
	t.Errorf("got %d, want %d", count, n)
	}
	}