Find file (space .)

Based on doom emacs find-file but also wanted to show an alternative to
file explorer helix-editor#2377.

helix-term/src/commands.rs

@@ -259,6 +259,7 @@ impl MappableCommand {
         command_mode, "Enter command mode",
         file_picker, "Open file picker",
         file_picker_in_current_directory, "Open file picker at current working directory",
+        find_file_picker, "Find file",
         code_action, "Perform code action",
         buffer_picker, "Open buffer picker",
         symbol_picker, "Open symbol picker",
@@ -2095,6 +2096,12 @@ fn file_picker_in_current_directory(cx: &mut Context) {
     cx.push_layer(Box::new(overlayed(picker)));
 }
 
+fn find_file_picker(cx: &mut Context) {
+    let cwd = std::env::current_dir().unwrap_or_else(|_| PathBuf::from("./"));
+    let picker = ui::find_file_picker(cwd, &cx.editor.config());
+    cx.push_layer(Box::new(overlayed(picker)));
+}
+
 fn buffer_picker(cx: &mut Context) {
     let current = view!(cx.editor).doc;
 

helix-term/src/keymap/default.rs

@@ -197,6 +197,7 @@ pub fn default() -> HashMap<Mode, Keymap> {
         "space" => { "Space"
             "f" => file_picker,
             "F" => file_picker_in_current_directory,
+            "." => find_file_picker,
             "b" => buffer_picker,
             "s" => symbol_picker,
             "S" => workspace_symbol_picker,

helix-term/src/ui/mod.rs

@@ -24,6 +24,7 @@ use helix_core::regex::Regex;
 use helix_core::regex::RegexBuilder;
 use helix_view::{Document, Editor, View};
 
+use std::fs;
 use std::path::PathBuf;
 
 pub fn prompt(
@@ -188,6 +189,36 @@ pub fn file_picker(root: PathBuf, config: &helix_view::editor::Config) -> FilePi
     )
 }
 
+/// Based on find-file on doom emacs (SPC . or SPC f f).
+pub fn find_file_picker(dir: PathBuf, config: &helix_view::editor::Config) -> FilePicker<PathBuf> {
+    // switch to Result::flatten later
+    let files: Vec<_> = match fs::read_dir(&dir) {
+        Ok(dir) => dir
+            .flat_map(|entry| entry.map(|entry| entry.path()))
+            .collect(),
+        Err(_) => Vec::new(),
+    };
+    let config = config.clone();
+    FilePicker::new(
+        files,
+        move |path| {
+            let suffix = if path.is_dir() { "/" } else { "" };
+            path.strip_prefix(&dir).unwrap_or(path).to_string_lossy() + suffix
+        },
+        move |cx, path, action| {
+            if path.is_dir() {
+                let _picker = find_file_picker(path.to_path_buf(), &config);
+                todo!("recurse picker, probably need to change how handle_event close_fn works");
+            } else {
+                cx.editor
+                    .open(path.into(), action)
+                    .expect("editor.open failed");
+            }
+        },
+        |_editor, path| Some((path.clone(), None)),
+    )
+}
+
 pub mod completers {
     use crate::ui::prompt::Completion;
     use fuzzy_matcher::skim::SkimMatcherV2 as Matcher;

helix-term/src/ui/picker.rs

@@ -34,19 +34,6 @@ pub const MIN_AREA_WIDTH_FOR_PREVIEW: u16 = 72;
 /// Biggest file size to preview in bytes
 pub const MAX_FILE_SIZE_FOR_PREVIEW: u64 = 10 * 1024 * 1024;
 
-/// File path and range of lines (used to align and highlight lines)
-pub type FileLocation = (PathBuf, Option<(usize, usize)>);
-
-pub struct FilePicker<T> {
-    picker: Picker<T>,
-    pub truncate_start: bool,
-    /// Caches paths to documents
-    preview_cache: HashMap<PathBuf, CachedPreview>,
-    read_buffer: Vec<u8>,
-    /// Given an item in the picker, return the file path and line number to display.
-    file_fn: Box<dyn Fn(&Editor, &T) -> Option<FileLocation>>,
-}
-
 pub enum CachedPreview {
     Document(Box<Document>),
     Binary,
@@ -84,6 +71,19 @@ impl Preview<'_, '_> {
     }
 }
 
+/// File path and range of lines (used to align and highlight lines)
+pub type FileLocation = (PathBuf, Option<(usize, usize)>);
+
+pub struct FilePicker<T> {
+    picker: Picker<T>,
+    pub truncate_start: bool,
+    /// Caches paths to documents
+    preview_cache: HashMap<PathBuf, CachedPreview>,
+    read_buffer: Vec<u8>,
+    /// Given an item in the picker, return the file path and line number to display.
+    file_fn: Box<dyn Fn(&Editor, &T) -> Option<FileLocation>>,
+}
+
 impl<T> FilePicker<T> {
     pub fn new(
         options: Vec<T>,