Added cause interface trait
diff --git a/errors.go b/errors.go
index 1c3c713..06e6f7e 100644
--- a/errors.go
+++ b/errors.go
@@ -33,3 +33,12 @@
}
return err
}
+
+// cause implements the interface required by Cause.
+type cause struct {
+ err error
+}
+
+func (c *cause) Cause() error {
+ return c.err
+}
diff --git a/errors_test.go b/errors_test.go
index 86a53a5..b88e016 100644
--- a/errors_test.go
+++ b/errors_test.go
@@ -38,11 +38,10 @@
func (nilError) Error() string { return "nil error" }
type causeError struct {
- err error
+ cause
}
func (e *causeError) Error() string { return "cause error" }
-func (e *causeError) Cause() error { return e.err }
func TestCause(t *testing.T) {
tests := []struct {
@@ -66,7 +65,7 @@
want: io.EOF,
}, {
// caused error returns cause
- err: &causeError{err: io.EOF},
+ err: &causeError{cause{err: io.EOF}},
want: io.EOF,
}}
