Removed Cause interface

fields.go

@@ -71,13 +71,6 @@ func (c *fields) Is(target error) bool {
 	return ok
 }
 
-// Cause returns the wrapped error which was the original
-// cause of the issue. We only support this because some code
-// depends on github.com/pkg/errors.Cause() returning the cause
-// of the error.
-// deprecated use error.Is() or error.As() instead
-func (c *fields) Cause() error { return c.wrapped }
-
 func (c *fields) Error() string {
 	return c.wrapped.Error()
 }

fields_test.go

@@ -31,7 +31,7 @@ func TestFields(t *testing.T) {
 
 		assert.Equal(t, "value1", m["key1"])
 		assert.Equal(t, "message: query error", m["err"])
-		assert.Len(t, m, 3)
+		assert.Len(t, m, 2)
 	})
 
 	t.Run("Can use errors.Is() from std `errors` package", func(t *testing.T) {
@@ -60,7 +60,6 @@ func TestFields(t *testing.T) {
 		out := fmt.Sprintf("%+v", wrap)
 		assert.Contains(t, out, `message: query error (key1=value1)`)
 
-		var f errors.HasFields
 		if errors.As(wrap, &f) {
 			slog.Error("this error has log fields", f.Fields()...)
 		}