From 42e0f0a225d0142eaea512fa4fecc08a2c1110ed Mon Sep 17 00:00:00 2001
From: Cole Helbling <cole.e.helbling@outlook.com>
Date: Tue, 23 Aug 2022 12:03:17 -0700
Subject: [PATCH] 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 |  1 +
 helix-term/src/commands/typed.rs  | 55 +++++++++++++++++++++++++------
 2 files changed, 46 insertions(+), 10 deletions(-)

diff --git a/book/src/generated/typable-cmd.md b/book/src/generated/typable-cmd.md
index 4cbff3061a440..296e9c9e9afdc 100644
--- a/book/src/generated/typable-cmd.md
+++ b/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. |
diff --git a/helix-term/src/commands/typed.rs b/helix-term/src/commands/typed.rs
index 96ff75c54a0f3..806e6fbaaef95 100644
--- a/helix-term/src/commands/typed.rs
+++ b/helix-term/src/commands/typed.rs
@@ -929,6 +929,43 @@ fn show_clipboard_provider(
     Ok(())
 }
 
+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>],
+    event: PromptEvent,
+) -> anyhow::Result<()> {
+    if event != PromptEvent::Validate {
+        return Ok(());
+    }
+
+    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 => {
+            bail!("Current document has no path");
+        }
+    };
+
+    change_directory_impl(cx, &dir)
+}
+
 fn change_current_directory(
     cx: &mut compositor::Context,
     args: &[Cow<str>],
@@ -945,16 +982,7 @@ fn change_current_directory(
             .as_ref(),
     );
 
-    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(())
+    change_directory_impl(cx, &dir)
 }
 
 fn show_current_directory(
@@ -1897,6 +1925,13 @@ pub const TYPABLE_COMMAND_LIST: &[TypableCommand] = &[
             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"],