Adding upstream version 0.28.1.

Signed-off-by: Daniel Baumann <daniel@debian.org>

core/db_retry_test.go

@@ -0,0 +1,66 @@
+package core
+
+import (
+	"errors"
+	"fmt"
+	"testing"
+)
+
+func TestGetDefaultRetryInterval(t *testing.T) {
+	t.Parallel()
+
+	if i := getDefaultRetryInterval(-1); i.Milliseconds() != 1000 {
+		t.Fatalf("Expected 1000ms, got %v", i)
+	}
+
+	if i := getDefaultRetryInterval(999); i.Milliseconds() != 1000 {
+		t.Fatalf("Expected 1000ms, got %v", i)
+	}
+
+	if i := getDefaultRetryInterval(3); i.Milliseconds() != 200 {
+		t.Fatalf("Expected 500ms, got %v", i)
+	}
+}
+
+func TestBaseLockRetry(t *testing.T) {
+	t.Parallel()
+
+	scenarios := []struct {
+		err              error
+		failUntilAttempt int
+		expectedAttempts int
+	}{
+		{nil, 3, 1},
+		{errors.New("test"), 3, 1},
+		{errors.New("database is locked"), 3, 3},
+		{errors.New("table is locked"), 3, 3},
+	}
+
+	for i, s := range scenarios {
+		t.Run(fmt.Sprintf("%d_%#v", i, s.err), func(t *testing.T) {
+			lastAttempt := 0
+
+			err := baseLockRetry(func(attempt int) error {
+				lastAttempt = attempt
+
+				if attempt < s.failUntilAttempt {
+					return s.err
+				}
+
+				return nil
+			}, s.failUntilAttempt+2)
+
+			if lastAttempt != s.expectedAttempts {
+				t.Errorf("Expected lastAttempt to be %d, got %d", s.expectedAttempts, lastAttempt)
+			}
+
+			if s.failUntilAttempt == s.expectedAttempts && err != nil {
+				t.Fatalf("Expected nil, got err %v", err)
+			}
+
+			if s.failUntilAttempt != s.expectedAttempts && s.err != nil && err == nil {
+				t.Fatalf("Expected error %q, got nil", s.err)
+			}
+		})
+	}
+}