Zero blobs, tests, documentation

tests/parallel/parallel_test.go

@@ -0,0 +1,191 @@
+package tests
+
+import (
+	"errors"
+	"io"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"testing"
+
+	"golang.org/x/sync/errgroup"
+
+	"github.com/ncruces/go-sqlite3"
+	_ "github.com/ncruces/go-sqlite3/embed"
+)
+
+func TestParallel(t *testing.T) {
+	name := filepath.Join(t.TempDir(), "test.db")
+	testParallel(t, name, 100)
+	testIntegrity(t, name)
+}
+
+func TestMultiProcess(t *testing.T) {
+	if testing.Short() {
+		t.Skip()
+	}
+
+	name := filepath.Join(t.TempDir(), "test.db")
+	t.Setenv("TestMultiProcess_dbname", name)
+
+	cmd := exec.Command("go", "test", "-v", "-run", "TestChildProcess")
+	out, err := cmd.StdoutPipe()
+	if err != nil {
+		t.Fatal(err)
+	}
+	if err := cmd.Start(); err != nil {
+		t.Fatal(err)
+	}
+
+	var buf [3]byte
+	// Wait for child to start.
+	if _, err := io.ReadFull(out, buf[:]); err != nil || string(buf[:]) != "===" {
+		t.Fatal(err)
+	}
+
+	testParallel(t, name, 1000)
+	if err := cmd.Wait(); err != nil {
+		t.Error(err)
+		var eerr *exec.ExitError
+		if errors.As(err, &eerr) {
+			t.Error(eerr.Stderr)
+		}
+	}
+	testIntegrity(t, name)
+}
+
+func TestChildProcess(t *testing.T) {
+	name := os.Getenv("TestMultiProcess_dbname")
+	if name == "" || testing.Short() {
+		t.SkipNow()
+	}
+
+	testParallel(t, name, 1000)
+}
+
+func testParallel(t *testing.T, name string, n int) {
+	writer := func() error {
+		db, err := sqlite3.Open(name)
+		if err != nil {
+			return err
+		}
+		defer db.Close()
+
+		err = db.Exec(`
+			PRAGMA locking_mode = NORMAL;
+			PRAGMA busy_timeout = 10000;
+		`)
+		if err != nil {
+			return err
+		}
+
+		err = db.Exec(`CREATE TABLE IF NOT EXISTS users (id INT, name VARCHAR(10))`)
+		if err != nil {
+			return err
+		}
+
+		err = db.Exec(`INSERT INTO users(id, name) VALUES(0, 'go'), (1, 'zig'), (2, 'whatever')`)
+		if err != nil {
+			return err
+		}
+
+		return db.Close()
+	}
+
+	reader := func() error {
+		db, err := sqlite3.Open(name)
+		if err != nil {
+			return err
+		}
+		defer db.Close()
+
+		err = db.Exec(`
+			PRAGMA locking_mode = NORMAL;
+			PRAGMA busy_timeout = 10000;
+		`)
+		if err != nil {
+			return err
+		}
+
+		stmt, _, err := db.Prepare(`SELECT id, name FROM users`)
+		if err != nil {
+			return err
+		}
+		defer stmt.Close()
+
+		row := 0
+		for stmt.Step() {
+			row++
+		}
+		if err := stmt.Err(); err != nil {
+			return err
+		}
+		if row%3 != 0 {
+			t.Errorf("got %d rows, want multiple of 3", row)
+		}
+
+		err = stmt.Close()
+		if err != nil {
+			return err
+		}
+
+		return db.Close()
+	}
+
+	err := writer()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	var group errgroup.Group
+	group.SetLimit(4)
+	for i := 0; i < n; i++ {
+		if i&7 != 7 {
+			group.Go(reader)
+		} else {
+			group.Go(writer)
+		}
+	}
+	err = group.Wait()
+	if err != nil {
+		t.Fatal(err)
+	}
+}
+
+func testIntegrity(t *testing.T, name string) {
+	db, err := sqlite3.Open(name)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer db.Close()
+
+	test := `PRAGMA integrity_check`
+	if testing.Short() {
+		test = `PRAGMA quick_check`
+	}
+
+	stmt, _, err := db.Prepare(test)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer stmt.Close()
+
+	for stmt.Step() {
+		if row := stmt.ColumnText(0); row != "ok" {
+			t.Error(row)
+		}
+	}
+	if err := stmt.Err(); err != nil {
+		t.Fatal(err)
+	}
+
+	err = stmt.Close()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	err = db.Close()
+	if err != nil {
+		t.Fatal(err)
+	}
+}