Fix expansion of `~` (#284)

* Fix expansion of `~`, dont use directory relative to cwd.

* Add `expand_tilde`

* Bring back `canonicalize_path`, use `expand_tilde` to `normalize`

* Make `:open ~` completion work

* Fix clippy

* Fold home dir into tilde in Document `realitve_path`

2 files changed, 17 insertions, 7 deletions

diff --git a/helix-term/src/commands.rs b/helix-term/src/commands.rs
index dc4805a5..b2dd0d11 100644
--- a/helix-term/src/commands.rs
+++ b/helix-term/src/commands.rs
@@ -1188,8 +1188,8 @@ mod cmd {
             .filter(|doc| doc.is_modified())
             .map(|doc| {
                 doc.relative_path()
-                    .and_then(|path| path.to_str())
-                    .unwrap_or("[scratch]")
+                    .map(|path| path.to_string_lossy().to_string())
+                    .unwrap_or_else(|| "[scratch]".into())
             })
             .collect();
         if !modified.is_empty() {
@@ -1487,7 +1487,7 @@ fn buffer_picker(cx: &mut Context) {
         cx.editor
             .documents
             .iter()
-            .map(|(id, doc)| (id, doc.relative_path().map(Path::to_path_buf)))
+            .map(|(id, doc)| (id, doc.relative_path()))
             .collect(),
         move |(id, path): &(DocumentId, Option<PathBuf>)| {
             // format_fn
diff --git a/helix-term/src/ui/mod.rs b/helix-term/src/ui/mod.rs
index b2274d06..39e11cd6 100644
--- a/helix-term/src/ui/mod.rs
+++ b/helix-term/src/ui/mod.rs
@@ -126,10 +126,11 @@ pub mod completers {
         use ignore::WalkBuilder;
         use std::path::{Path, PathBuf};
 
-        let path = Path::new(input);
+        let is_tilde = input.starts_with('~') && input.len() == 1;
+        let path = helix_view::document::expand_tilde(Path::new(input));
 
         let (dir, file_name) = if input.ends_with('/') {
-            (path.into(), None)
+            (path, None)
         } else {
             let file_name = path
                 .file_name()
@@ -154,7 +155,16 @@ pub mod completers {
                     let is_dir = entry.file_type().map_or(false, |entry| entry.is_dir());
 
                     let path = entry.path();
-                    let mut path = path.strip_prefix(&dir).unwrap_or(path).to_path_buf();
+                    let mut path = if is_tilde {
+                        // if it's a single tilde an absolute path is displayed so that when `TAB` is pressed on
+                        // one of the directories the tilde will be replaced with a valid path not with a relative
+                        // home directory name.
+                        // ~ -> <TAB> -> /home/user
+                        // ~/ -> <TAB> -> ~/first_entry
+                        path.to_path_buf()
+                    } else {
+                        path.strip_prefix(&dir).unwrap_or(path).to_path_buf()
+                    };
 
                     if is_dir {
                         path.push("");
@@ -184,7 +194,7 @@ pub mod completers {
                 })
                 .collect();
 
-            let range = ((input.len() - file_name.len())..);
+            let range = ((input.len().saturating_sub(file_name.len()))..);
 
             matches.sort_unstable_by_key(|(_file, score)| Reverse(*score));
             files = matches