Try to find misuses of textui.Progress

 - Add a runtime-check to Progress to notice if we deadlocked or
   forgot to call .Done().

 - Add a runtime-check to Progress.Done() to panic if .Set() was never
   called (instead of the old behavior of deadlocking).

 - grep: Use `defer` when possible, to help remember to call .Done().

 - grep: Always either call .Set() right away, or right before calling
   .Done().

1 files changed, 3 insertions, 5 deletions

diff --git a/lib/btrfsutil/rebuilt_tree.go b/lib/btrfsutil/rebuilt_tree.go
index ffb2e5f..31a31be 100644
--- a/lib/btrfsutil/rebuilt_tree.go
+++ b/lib/btrfsutil/rebuilt_tree.go
@@ -259,11 +259,9 @@ func (tree *RebuiltTree) items(ctx context.Context, inc bool) containers.SortedM
 			progressWriter.Set(stats)
 		}
 	}
-	if stats.Leafs.N > 0 {
-		stats.Leafs.N = stats.Leafs.D
-		progressWriter.Set(stats)
-		progressWriter.Done()
-	}
+	stats.Leafs.N = stats.Leafs.D
+	progressWriter.Set(stats)
+	progressWriter.Done()
 
 	return index
 }