More test assert fixes

Follow up to prometheus/client_golang#1424

Signed-off-by: György Krajcsovits <gyorgy.krajcsovits@grafana.com>

Author: krajorama

pkg/compactor/blocks_cleaner_test.go

@@ -464,12 +464,7 @@ func TestBlocksCleaner_ShouldNotCleanupUserThatDoesntBelongToShardAnymore(t *tes
 	require.ElementsMatch(t, []string{"user-1", "user-2"}, cleaner.lastOwnedUsers)
 
 	// But there are no metrics for any user, because we did not in fact clean them.
-	assert.NoError(t, testutil.GatherAndCompare(reg, strings.NewReader(`
-		# HELP cortex_bucket_blocks_count Total number of blocks in the bucket. Includes blocks marked for deletion, but not partial blocks.
-		# TYPE cortex_bucket_blocks_count gauge
-	`),
-		"cortex_bucket_blocks_count",
-	))
+	assert.ErrorContains(t, testutil.GatherAndCompare(reg, strings.NewReader(""), "cortex_bucket_blocks_count"), "expected metric name(s) not found")
 
 	// Running cleanUsers again will see that users are no longer owned.
 	require.NoError(t, cleaner.runCleanupWithErr(ctx))

pkg/compactor/compactor_test.go

@@ -965,7 +965,6 @@ func TestMultitenantCompactor_ShouldNotCompactBlocksForUsersMarkedForDeletion(t
 		"cortex_compactor_runs_started_total", "cortex_compactor_runs_completed_total", "cortex_compactor_runs_failed_total",
 		"cortex_compactor_blocks_cleaned_total", "cortex_compactor_block_cleanup_failures_total", "cortex_compactor_blocks_marked_for_deletion_total",
 		"cortex_compactor_block_cleanup_started_total", "cortex_compactor_block_cleanup_completed_total", "cortex_compactor_block_cleanup_failed_total",
-		"cortex_bucket_blocks_count", "cortex_bucket_blocks_marked_for_deletion_count", "cortex_bucket_index_last_successful_update_timestamp_seconds",
 	}
 	assert.NoError(t, prom_testutil.GatherAndCompare(registry, strings.NewReader(`
 		# TYPE cortex_compactor_runs_started_total counter
@@ -1007,6 +1006,12 @@ func TestMultitenantCompactor_ShouldNotCompactBlocksForUsersMarkedForDeletion(t
 		# HELP cortex_compactor_block_cleanup_failed_total Total number of blocks cleanup runs failed.
 		cortex_compactor_block_cleanup_failed_total 0
 	`), testedMetrics...))
+	assert.ErrorContains(t, prom_testutil.GatherAndCompare(registry, strings.NewReader(""),
+		"cortex_bucket_blocks_count",
+		"cortex_bucket_blocks_marked_for_deletion_count",
+		"cortex_bucket_index_last_successful_update_timestamp_seconds"),
+		"expected metric name(s) not found",
+	)
 }
 
 func TestMultitenantCompactor_ShouldCompactAllUsersOnShardingEnabledButOnlyOneInstanceRunning(t *testing.T) {