Improve proc tree expand/collapse functionality

docs/content/usage/widgets/process.md

@@ -83,7 +83,7 @@ Pressing ++t++ or ++f5++ in the table toggles tree mode in the process widget, d
     <img src="../../../assets/screenshots/process/process_tree.webp" alt="A picture of tree mode in a process widget."/>
 </figure>
 
-A process in tree mode can also be "collapsed", hiding its children and any descendants, using either the ++minus++ or ++plus++ keys, or double clicking on an entry.
+A process in tree mode can also be "collapsed", hiding its children and any descendants, using either the ++minus++ or ++Left++ keys, or clicking on an entry.  To expand, use the ++plus++ or ++Right++ keys, or click on the entry again.
 
 Lastly, note that in tree mode, processes cannot be grouped together due to the behaviour of the two modes somewhat clashing.
 

src/app.rs

@@ -705,6 +705,9 @@ impl App {
                         }
                     }
                 }
+                BottomWidgetType::Proc => {
+                    self.toggle_collapsing_process_branch(Some(false));
+                }
                 _ => {}
             }
         } else if self.delete_dialog_state.is_showing_dd {
@@ -769,6 +772,9 @@ impl App {
                         }
                     }
                 }
+                BottomWidgetType::Proc => {
+                    self.toggle_collapsing_process_branch(Some(true));
+                }
                 _ => {}
             }
         } else if self.delete_dialog_state.is_showing_dd {
@@ -2138,7 +2144,7 @@ impl App {
     fn on_plus(&mut self) {
         if let BottomWidgetType::Proc = self.current_widget.widget_type {
             // Toggle collapsing if tree
-            self.toggle_collapsing_process_branch();
+            self.toggle_collapsing_process_branch(Some(true));
         } else {
             self.zoom_in();
         }
@@ -2147,20 +2153,20 @@ impl App {
     fn on_minus(&mut self) {
         if let BottomWidgetType::Proc = self.current_widget.widget_type {
             // Toggle collapsing if tree
-            self.toggle_collapsing_process_branch();
+            self.toggle_collapsing_process_branch(Some(false));
         } else {
             self.zoom_out();
         }
     }
 
-    fn toggle_collapsing_process_branch(&mut self) {
+    fn toggle_collapsing_process_branch(&mut self, force_expand: Option<bool>) {
         if let Some(pws) = self
             .states
             .proc_state
             .widget_states
             .get_mut(&self.current_widget.widget_id)
         {
-            pws.toggle_current_tree_branch_entry();
+            pws.toggle_current_tree_branch_entry(force_expand);
         }
     }
 
@@ -2579,7 +2585,7 @@ impl App {
                                             // the same entry as the already selected one - if it is,
                                             // then we minimize.
                                             if is_tree_mode && change == 0 {
-                                                self.toggle_collapsing_process_branch();
+                                                self.toggle_collapsing_process_branch(None);
                                             }
                                         }
                                     }

src/app/data_harvester/disks/unix/linux/partition.rs

@@ -110,7 +110,7 @@ impl FromStr for Partition {
         let mut parts = line.splitn(5, ' ');
 
         let device = match parts.next() {
-            Some(device) if device == "none" => None,
+            Some("none") => None,
             Some(device) => Some(device.to_string()),
             None => {
                 bail!("missing device");

src/constants.rs

@@ -327,7 +327,7 @@ pub const CPU_HELP_TEXT: [&str; 2] = [
     "Mouse scroll     Scrolling over an CPU core/average shows only that entry on the chart",
 ];
 
-pub const PROCESS_HELP_TEXT: [&str; 15] = [
+pub const PROCESS_HELP_TEXT: [&str; 16] = [
     "3 - Process widget",
     "dd, F9           Kill the selected process",
     "c                Sort by CPU usage, press again to reverse",
@@ -341,7 +341,8 @@ pub const PROCESS_HELP_TEXT: [&str; 15] = [
     "I                Invert current sort",
     "%                Toggle between values and percentages for memory usage",
     "t, F5            Toggle tree mode",
-    "+, -, click      Collapse/expand a branch while in tree mode",
+    "-, Left, click   Collapse a branch while in tree mode",
+    "+, Right, click  Expand a branch while in tree mode",
     "click on header  Sorts the entries by that column, click again to invert the sort",
 ];
 

src/widgets/process_table.rs

@@ -794,15 +794,29 @@ impl ProcWidgetState {
         }
     }
 
-    pub fn toggle_current_tree_branch_entry(&mut self) {
+    /// Change the state of a tree branch:
+    ///   None - toggle the branch between collapsed and expanded
+    ///   Some(true) - expand the branch, or do nothing if it's already expanded
+    ///   Some(false) - collapse the branch, or do nothing if it's already collapsed
+    pub fn toggle_current_tree_branch_entry(&mut self, force_expand: Option<bool>) {
         if let ProcWidgetMode::Tree { collapsed_pids } = &mut self.mode {
             if let Some(process) = self.table.current_item() {
                 let pid = process.pid;
 
-                if !collapsed_pids.remove(&pid) {
-                    collapsed_pids.insert(pid);
+                let refresh = match force_expand {
+                    Some(true) => collapsed_pids.remove(&pid),
+                    Some(false) => collapsed_pids.insert(pid),
+                    None => {
+                        if !collapsed_pids.remove(&pid) {
+                            collapsed_pids.insert(pid);
+                        }
+                        true
+                    }
+                };
+
+                if refresh {
+                    self.force_data_update();
                 }
-                self.force_data_update();
             }
         }
     }