Treat custom textfile metric timestamps as errors (#769)

This is clearer behavior and users will notice and fix their textfiles faster
than if we just output a warning.

1 files changed, 4 insertions, 0 deletions

diff --git a/collector/textfile_test.go b/collector/textfile_test.go
index 47e1832..fb1a700 100644
--- a/collector/textfile_test.go
+++ b/collector/textfile_test.go
@@ -63,6 +63,10 @@ func TestTextfileCollector(t *testing.T) {
                         out:  "fixtures/textfile/nonexistent_path.out",
                 },
                 {
+                        path: "fixtures/textfile/client_side_timestamp",
+                        out:  "fixtures/textfile/client_side_timestamp.out",
+                },
+                {
                         path: "fixtures/textfile/different_metric_types",
                         out:  "fixtures/textfile/different_metric_types.out",
                 },