do not merge; incredibly hacky fix for console-rs#451

src/multi.rs

@@ -187,6 +187,8 @@ pub(crate) struct MultiState {
     alignment: MultiProgressAlignment,
     /// Orphaned lines are carried over across draw operations
     orphan_lines: Vec<String>,
+    /// Number of lines from zombies that have been reaped
+    zombie_line_count: usize,
 }
 
 impl MultiState {
@@ -199,6 +201,7 @@ impl MultiState {
             move_cursor: false,
             alignment: Default::default(),
             orphan_lines: Vec::new(),
+            zombie_line_count: 0,
         }
     }
 
@@ -227,6 +230,7 @@ impl MultiState {
         // Adjust last line count so we don't clear too many lines
         if let Some(last_line_count) = self.draw_target.last_line_count() {
             *last_line_count -= adjust;
+            self.zombie_line_count += adjust;
         }
 
         let orphan_lines_count = self.orphan_lines.len();
@@ -343,10 +347,27 @@ impl MultiState {
     }
 
     fn clear(&mut self, now: Instant) -> io::Result<()> {
-        match self.draw_target.drawable(true, now) {
-            Some(drawable) => drawable.clear(),
+        let mut old_zombie_count = 0;
+        if let Some(last_line_count) = self.draw_target.last_line_count() {
+            *last_line_count += self.zombie_line_count;
+            old_zombie_count = self.zombie_line_count;
+            self.zombie_line_count = 0;
+        }
+
+        let ret = match self.draw_target.drawable(true, now) {
+            Some(drawable) => {
+                old_zombie_count = 0;
+                drawable.clear()
+            },
             None => Ok(()),
+        };
+
+        if let Some(last_line_count) = self.draw_target.last_line_count() {
+            *last_line_count -= old_zombie_count;
+            self.zombie_line_count = old_zombie_count;
         }
+
+        ret
     }
 
     fn remove_idx(&mut self, idx: usize) {