helix-term: introduce cdf / change-directory-to-current-file

This will set the current working directory to that of the current
file's parent.

book/src/generated/typable-cmd.md

@@ -41,6 +41,7 @@
 | `:primary-clipboard-paste-replace` | Replace selections with content of system primary clipboard. |
 | `:show-clipboard-provider` | Show clipboard provider name in status bar. |
 | `:change-current-directory`, `:cd` | Change the current working directory. |
+| `:change-directory-to-current-file`, `:cdf` | Change the current working directory to the parent of the current document if provided no arguments. |
 | `:show-directory`, `:pwd` | Show the current working directory. |
 | `:encoding` | Set encoding. Based on `https://encoding.spec.whatwg.org`. |
 | `:reload` | Discard changes and reload from the source file. |

helix-term/src/commands/typed.rs

@@ -929,41 +929,60 @@ fn show_clipboard_provider(
     Ok(())
 }
 
-fn change_current_directory(
+fn change_directory_impl(cx: &mut compositor::Context, dir: &Path) -> anyhow::Result<()> {
+    if let Err(e) = std::env::set_current_dir(dir) {
+        bail!("Couldn't change the current working directory: {}", e);
+    }
+
+    let cwd = std::env::current_dir().context("Couldn't get the new working directory")?;
+    cx.editor.set_status(format!(
+        "Current working directory is now {}",
+        cwd.display()
+    ));
+
+    Ok(())
+}
+
+fn change_directory_to_current_file(
     cx: &mut compositor::Context,
-    args: &[Cow<str>],
+    _args: &[Cow<str>],
     event: PromptEvent,
 ) -> anyhow::Result<()> {
     if event != PromptEvent::Validate {
         return Ok(());
     }
 
-    let dir = match args.first() {
-        Some(dir) => helix_core::path::expand_tilde(dir.as_ref().as_ref()),
+    let (_, doc) = current_ref!(cx.editor);
+    let dir = match doc.path() {
+        Some(path) => path
+            .parent()
+            .map(ToOwned::to_owned)
+            .context("Couldn't get parent of current document")?,
         None => {
-            let (_, doc) = current_ref!(cx.editor);
-            match doc.path() {
-                Some(path) => path
-                    .parent()
-                    .map(ToOwned::to_owned)
-                    .context("Couldn't get parent of current document")?,
-                None => {
-                    bail!("Current document has no path");
-                }
-            }
+            bail!("Current document has no path");
         }
     };
 
-    if let Err(e) = std::env::set_current_dir(dir) {
-        bail!("Couldn't change the current working directory: {}", e);
+    change_directory_impl(cx, &dir)
+}
+
+fn change_current_directory(
+    cx: &mut compositor::Context,
+    args: &[Cow<str>],
+    event: PromptEvent,
+) -> anyhow::Result<()> {
+    if event != PromptEvent::Validate {
+        return Ok(());
     }
 
-    let cwd = std::env::current_dir().context("Couldn't get the new working directory")?;
-    cx.editor.set_status(format!(
-        "Current working directory is now {}",
-        cwd.display()
-    ));
-    Ok(())
+    let dir = helix_core::path::expand_tilde(
+        args.first()
+            .context("target directory not provided")?
+            .as_ref()
+            .as_ref(),
+    );
+
+    change_directory_impl(cx, &dir)
 }
 
 fn show_current_directory(
@@ -1902,10 +1921,17 @@ pub const TYPABLE_COMMAND_LIST: &[TypableCommand] = &[
         TypableCommand {
             name: "change-current-directory",
             aliases: &["cd"],
-            doc: "Change the current working directory. Uses the parent of the current document if provided no arguments.",
+            doc: "Change the current working directory.",
             fun: change_current_directory,
             completer: Some(completers::directory),
         },
+        TypableCommand {
+            name: "change-directory-to-current-file",
+            aliases: &["cdf"],
+            doc: "Change the current working directory to the parent of the current document if provided no arguments.",
+            fun: change_directory_to_current_file,
+            completer: Some(completers::directory),
+        },
         TypableCommand {
             name: "show-directory",
             aliases: &["pwd"],