On X11, simplify available_monitors() impl

psychon · kchibisov · commit 87fc19826b09 · 2023-12-24T23:55:50.000+04:00
This code confused me. I tried to understand it. I tried to simplify it
while keeping the functional style. But in the end, this just seems too
complicated for its own good. Just doing the exact same thing with a
match statement and the question mark operator makes it sooo much more
obvious what is happening.

Signed-off-by: Uli Schlachter &lt;psychon@znc.in&gt;
diff --git a/src/platform_impl/linux/x11/monitor.rs b/src/platform_impl/linux/x11/monitor.rs
@@ -284,22 +284,16 @@ impl XConnection {
 
     pub fn available_monitors(&self) -> Result<Vec<MonitorHandle>, X11Error> {
         let mut monitors_lock = self.monitor_handles.lock().unwrap();
-        (*monitors_lock)
-            .as_ref()
-            .cloned()
-            .map(Ok)
-            .or_else(|| {
-                self.query_monitor_list()
-                    .map(|mon_list| {
-                        let monitors = Some(mon_list);
-                        if !DISABLE_MONITOR_LIST_CACHING {
-                            (*monitors_lock) = monitors.clone();
-                        }
-                        monitors
-                    })
-                    .transpose()
-            })
-            .unwrap()
+        match *monitors_lock {
+            Some(ref monitors) => Ok(monitors.clone()),
+            None => {
+                let monitors = self.query_monitor_list()?;
+                if !DISABLE_MONITOR_LIST_CACHING {
+                    *monitors_lock = Some(monitors.clone());
+                }
+                Ok(monitors)
+            }
+        }
     }
 
     #[inline]
