From eba0bbda2ee10e9ba53f01f1d324d2c4c82229d2 Mon Sep 17 00:00:00 2001
From: Ivan Tham <pickfire@riseup.net>
Date: Sun, 18 Jul 2021 12:24:07 +0800
Subject: [PATCH] Resume last picker

Inspired by space ' in doom emacs.
---
 helix-term/src/commands.rs   | 14 ++++++++++++++
 helix-term/src/compositor.rs |  7 +++++--
 helix-term/src/ui/picker.rs  |  2 +-
 3 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/helix-term/src/commands.rs b/helix-term/src/commands.rs
index 5fc96cd9..9b72a8e9 100644
--- a/helix-term/src/commands.rs
+++ b/helix-term/src/commands.rs
@@ -217,6 +217,7 @@ impl Command {
         file_picker,
         buffer_picker,
         symbol_picker,
+        last_picker,
         prepend_to_line,
         append_to_line,
         open_below,
@@ -2091,6 +2092,17 @@ fn symbol_picker(cx: &mut Context) {
     )
 }
 
+fn last_picker(cx: &mut Context) {
+    // TODO: last picker does not seemed to work well with buffer_picker
+    cx.callback = Some(Box::new(|compositor: &mut Compositor| {
+        if let Some(picker) = compositor.last_picker.take() {
+            compositor.push(picker);
+        }
+        // XXX: figure out how to show error when no last picker lifetime
+        // cx.editor.set_error("no last picker".to_owned())
+    }));
+}
+
 // I inserts at the first nonwhitespace character of each line with a selection
 fn prepend_to_line(cx: &mut Context) {
     goto_first_nonwhitespace(cx);
@@ -3749,6 +3761,8 @@ macro_rules! mode_info {
 mode_info! {
     /// space mode
     space_mode, SPACE_MODE,
+    /// resume last picker
+    "'" => last_picker,
     /// file picker
     "f" => file_picker,
     /// buffer picker
diff --git a/helix-term/src/compositor.rs b/helix-term/src/compositor.rs
index 5fcb552a..c2cfa3a7 100644
--- a/helix-term/src/compositor.rs
+++ b/helix-term/src/compositor.rs
@@ -74,6 +74,8 @@ type Terminal = tui::terminal::Terminal<CrosstermBackend<std::io::Stdout>>;
 pub struct Compositor {
     layers: Vec<Box<dyn Component>>,
     terminal: Terminal,
+
+    pub(crate) last_picker: Option<Box<dyn Component>>,
 }
 
 impl Compositor {
@@ -83,6 +85,7 @@ impl Compositor {
         Ok(Self {
             layers: Vec::new(),
             terminal,
+            last_picker: None,
         })
     }
 
@@ -103,8 +106,8 @@ impl Compositor {
         self.layers.push(layer);
     }
 
-    pub fn pop(&mut self) {
-        self.layers.pop();
+    pub fn pop(&mut self) -> Option<Box<dyn Component>> {
+        self.layers.pop()
     }
 
     pub fn handle_event(&mut self, event: Event, cx: &mut Context) -> bool {
diff --git a/helix-term/src/ui/picker.rs b/helix-term/src/ui/picker.rs
index d7fc9d86..733be2fc 100644
--- a/helix-term/src/ui/picker.rs
+++ b/helix-term/src/ui/picker.rs
@@ -159,7 +159,7 @@ impl<T: 'static> Component for Picker<T> {
 
         let close_fn = EventResult::Consumed(Some(Box::new(|compositor: &mut Compositor| {
             // remove the layer
-            compositor.pop();
+            compositor.last_picker = compositor.pop();
         })));
 
         match key_event {