Merge pull request #260 from cole-miller/shell

Always use QUERY_SQL in the dqlite shell

driver/driver_test.go

@@ -567,6 +567,22 @@ func Test_ColumnTypesEnd(t *testing.T) {
 	assert.NoError(t, conn.Close())
 }
 
+func Test_ZeroColumns(t *testing.T) {
+	drv, cleanup := newDriver(t)
+	defer cleanup()
+
+	conn, err := drv.Open("test.db")
+	require.NoError(t, err)
+	queryer := conn.(driver.Queryer)
+
+	rows, err := queryer.Query("CREATE TABLE foo (bar INTEGER)", []driver.Value{})
+	require.NoError(t, err)
+	values := []driver.Value{}
+	require.Equal(t, io.EOF, rows.Next(values))
+
+	require.NoError(t, conn.Close())
+}
+
 func newDriver(t *testing.T) (*dqlitedriver.Driver, func()) {
 	t.Helper()
 

internal/protocol/message.go

@@ -478,6 +478,12 @@ func (r *Rows) columnTypes(save bool) ([]uint8, error) {
 		r.types = make([]uint8, len(r.Columns))
 	}
 
+	// If there are zero columns, no rows can be encoded or decoded,
+	// so we signal EOF immediately.
+	if len(r.types) == 0 {
+		return r.types, io.EOF
+	}
+
 	// Each column needs a 4 byte slot to store the column type. The row
 	// header must be padded to reach word boundary.
 	headerBits := len(r.types) * 4

internal/shell/shell.go

@@ -87,11 +87,7 @@ func (s *Shell) Process(ctx context.Context, line string) (string, error) {
 	if strings.HasPrefix(strings.ToLower(strings.TrimLeft(line, " ")), ".reconfigure") {
 		return s.processReconfigure(ctx, line)
 	}
-	if strings.HasPrefix(strings.ToUpper(strings.TrimLeft(line, " ")), "SELECT") {
-		return s.processSelect(ctx, line)
-	} else {
-		return "", s.processExec(ctx, line)
-	}
+	return s.processQuery(ctx, line)
 }
 
 func (s *Shell) processHelp() string {
@@ -317,7 +313,7 @@ func (s *Shell) processWeight(ctx context.Context, line string) (string, error)
 	return "", nil
 }
 
-func (s *Shell) processSelect(ctx context.Context, line string) (string, error) {
+func (s *Shell) processQuery(ctx context.Context, line string) (string, error) {
 	tx, err := s.db.BeginTx(ctx, nil)
 	if err != nil {
 		return "", fmt.Errorf("begin transaction: %w", err)