internal: add Multistatus.Get test with HTTP error

References: https://github.com/emersion/go-webdav/issues/39

internal/elements_test.go

@@ -0,0 +1,34 @@
+package internal
+
+import (
+	"encoding/xml"
+	"strings"
+	"testing"
+)
+
+// https://tools.ietf.org/html/rfc4918#section-9.6.2
+const exampleDeleteMultistatusStr = `<?xml version="1.0" encoding="utf-8" ?>
+<d:multistatus xmlns:d="DAV:">
+  <d:response>
+    <d:href>http://www.example.com/container/resource3</d:href>
+    <d:status>HTTP/1.1 423 Locked</d:status>
+    <d:error><d:lock-token-submitted/></d:error>
+  </d:response>
+</d:multistatus>`
+
+func TestMultistatus_Get_error(t *testing.T) {
+	r := strings.NewReader(exampleDeleteMultistatusStr)
+	var ms Multistatus
+	if err := xml.NewDecoder(r).Decode(&ms); err != nil {
+		t.Fatalf("Decode() = %v", err)
+	}
+
+	_, err := ms.Get("/container/resource3")
+	if err == nil {
+		t.Errorf("Multistatus.Get() returned a nil error, expected non-nil")
+	} else if httpErr, ok := err.(*HTTPError); !ok {
+		t.Errorf("Multistatus.Get() = %T, expected an *HTTPError", err)
+	} else if httpErr.Code != 423 {
+		t.Errorf("HTTPError.Code = %v, expected 423", httpErr.Code)
+	}
+}