Only get draw_target-width when we actually draw

src/state.rs

@@ -183,26 +183,28 @@ impl BarState {
     }
 
     pub(crate) fn draw(&mut self, mut force_draw: bool, now: Instant) -> io::Result<()> {
-        let width = self.draw_target.width();
-
         // `|= self.is_finished()` should not be needed here, but we used to always draw for
         // finished progress bars, so it's kept as to not cause compatibility issues in weird cases.
         force_draw |= self.state.is_finished();
-        let mut drawable = match self.draw_target.drawable(force_draw, now) {
-            Some(drawable) => drawable,
-            None => return Ok(()),
-        };
 
-        let mut draw_state = drawable.state();
+        // First check whether there is something to be drawn.
+        if self.draw_target.drawable(force_draw, now).is_none() {
+            return Ok(());
+        }
+        // Then, get the target width.
+        // This is an expensive operation, and should only happen when we actually do some work.
+        let width = self.draw_target.width();
+
+        // Now actually get the drawable.
+        let mut drawable = self.draw_target.drawable(force_draw, now).unwrap();
 
         if let Some(width) = width {
             if !matches!(self.state.status, Status::DoneHidden) {
                 self.style
-                    .format_state(&self.state, &mut draw_state.lines, width);
+                    .format_state(&self.state, &mut drawable.state().lines, width);
             }
         }
 
-        drop(draw_state);
         drawable.draw()
     }
 }