From e4ff75b4d4eb793004e91279c82fde7766fc5a00 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Bla=C5=BE=20Hrastnik?= <blaz@mxxn.io>
Date: Wed, 12 May 2021 17:24:55 +0900
Subject: [PATCH] Add :fmt (formats the whole file).

---
 helix-lsp/src/lib.rs       |  2 ++
 helix-term/src/commands.rs | 31 +++++++++++++++++++++++++++++++
 2 files changed, 33 insertions(+)

diff --git a/helix-lsp/src/lib.rs b/helix-lsp/src/lib.rs
index 1dbd6529d..0a83c93a6 100644
--- a/helix-lsp/src/lib.rs
+++ b/helix-lsp/src/lib.rs
@@ -20,6 +20,8 @@ use serde::{Deserialize, Serialize};
 
 use tokio_stream::wrappers::UnboundedReceiverStream;
 
+pub use futures_executor::block_on;
+
 #[derive(Error, Debug)]
 pub enum Error {
     #[error("protocol error: {0}")]
diff --git a/helix-term/src/commands.rs b/helix-term/src/commands.rs
index e26dbbaad..4a42bbbae 100644
--- a/helix-term/src/commands.rs
+++ b/helix-term/src/commands.rs
@@ -888,10 +888,34 @@ mod cmd {
         }
         tokio::spawn(doc.save());
     }
+
     fn new_file(editor: &mut Editor, args: &[&str], event: PromptEvent) {
         editor.new_file(Action::Replace);
     }
 
+    fn format(editor: &mut Editor, args: &[&str], event: PromptEvent) {
+        let (view, doc) = editor.current();
+
+        if let Some(language_server) = doc.language_server() {
+            // TODO: await, no blocking
+            let transaction = helix_lsp::block_on(
+                language_server
+                    .text_document_formatting(doc.identifier(), lsp::FormattingOptions::default()),
+            )
+            .map(|edits| {
+                helix_lsp::util::generate_transaction_from_edits(
+                    doc.text(),
+                    edits,
+                    language_server.offset_encoding(),
+                )
+            });
+
+            if let Ok(transaction) = transaction {
+                doc.apply(&transaction, view.id);
+            }
+        }
+    }
+
     pub const COMMAND_LIST: &[Command] = &[
         Command {
             name: "quit",
@@ -928,6 +952,13 @@ mod cmd {
             fun: new_file,
             completer: Some(completers::filename),
         },
+        Command {
+            name: "format",
+            alias: Some("fmt"),
+            doc: "Format the file using a formatter.",
+            fun: format,
+            completer: None,
+        },
     ];
 
     pub static COMMANDS: Lazy<HashMap<&'static str, &'static Command>> = Lazy::new(|| {