Don't panic if api_info doesn't exist on gui_event, make Option

[(Lyude: also, use map_or() for guessing channel ID for shutdown())]

Resolves #51
Closes #49

src/nvim/client.rs

@@ -104,13 +104,8 @@ impl NeovimClient {
         self.nvim.write().unwrap().replace(nvim);
     }
 
-    pub fn api_info(&self) -> Rc<NeovimApiInfo> {
-        self.state
-            .borrow()
-            .api_info
-            .as_ref()
-            .expect("API info should be initialized by the time this is called")
-            .clone()
+    pub fn api_info(&self) -> Option<Rc<NeovimApiInfo>> {
+        self.state.borrow().api_info.as_ref().cloned()
     }
 
     pub fn set_initialized(&self, api_info: NeovimApiInfo) {

src/nvim/redraw_handler.rs

@@ -239,18 +239,46 @@ pub fn call_gui_event(
             match opt_name.as_str() {
                 "Popupmenu" => set_ui_opt(
                     &nvim,
-                    &[("ext_popupmenu", api_info.ext_popupmenu)],
+                    &[(
+                        "ext_popupmenu",
+                        api_info
+                            .as_ref()
+                            .map(|api_info| api_info.ext_popupmenu)
+                            .unwrap_or_default(),
+                    )],
                     opt_value,
                 )?,
                 "Tabline" => {
-                    set_ui_opt(&nvim, &[("ext_tabline", api_info.ext_tabline)], opt_value)?;
+                    set_ui_opt(
+                        &nvim,
+                        &[(
+                            "ext_tabline",
+                            api_info
+                                .as_ref()
+                                .map(|api_info| api_info.ext_tabline)
+                                .unwrap_or_default(),
+                        )],
+                        opt_value,
+                    )?;
                     ui.set_tabline(opt_value);
                 }
                 "Cmdline" => set_ui_opt(
                     &nvim,
                     &[
-                        ("ext_cmdline", api_info.ext_cmdline),
-                        ("ext_wildmenu", api_info.ext_wildmenu),
+                        (
+                            "ext_cmdline",
+                            api_info
+                                .as_ref()
+                                .map(|api_info| api_info.ext_cmdline)
+                                .unwrap_or_default(),
+                        ),
+                        (
+                            "ext_wildmenu",
+                            api_info
+                                .as_ref()
+                                .map(|api_info| api_info.ext_wildmenu)
+                                .unwrap_or_default(),
+                        ),
                     ],
                     opt_value,
                 )?,

src/shell.rs

@@ -1227,12 +1227,12 @@ impl Shell {
     pub fn detach_ui(&self) {
         let state = self.state.borrow();
         let nvim_client = state.nvim.clone();
+        let api_info = nvim_client.api_info();
 
         if let Some(nvim) = nvim_client.nvim() {
-            let api_info = nvim_client.api_info();
             nvim_client.clear();
             nvim.block_timeout(nvim.ui_detach()).report_err();
-            nvim.block_on(nvim.shutdown(api_info.channel));
+            nvim.block_on(nvim.shutdown(api_info.map_or(1, |i| i.channel)));
         }
     }
 

src/ui.rs

@@ -405,7 +405,10 @@ impl Ui {
         let commands = commands.join("|");
         let nvim_client = shell.nvim_clone();
         let nvim = nvim_client.nvim().unwrap();
-        let channel_id = nvim_client.api_info().channel;
+        let channel_id = nvim_client
+            .api_info()
+            .expect("API info should be initialized by the time this is called")
+            .channel;
         nvim.clone().spawn(async move {
             let res = nvim.command(&commands).await;