From e8add6f46d0f208c96407151276a985dd34fc93f Mon Sep 17 00:00:00 2001
From: A-Walrus <ofek.r.guy@gmail.com>
Date: Mon, 8 Aug 2022 22:04:41 +0300
Subject: [PATCH] Add error handling to set language command

If you type a nonexistant language an appropriate message will show,
and the language won't be changed.
---
 helix-term/src/commands/typed.rs | 11 ++++++++++-
 helix-view/src/document.rs       |  6 +++++-
 2 files changed, 15 insertions(+), 2 deletions(-)

diff --git a/helix-term/src/commands/typed.rs b/helix-term/src/commands/typed.rs
index f005d9bf6..127eea0dc 100644
--- a/helix-term/src/commands/typed.rs
+++ b/helix-term/src/commands/typed.rs
@@ -1253,7 +1253,16 @@ fn language(
     }
 
     let doc = doc_mut!(cx.editor);
-    doc.set_language_by_language_id(&args[0], cx.editor.syn_loader.clone());
+
+    let loader = cx.editor.syn_loader.clone();
+    if args[0] == "text" {
+        doc.set_language(None, Some(loader))
+    } else {
+        let ok = doc.set_language_by_language_id(&args[0], loader);
+        if !ok {
+            anyhow::bail!("invalid language: {}", args[0]);
+        }
+    }
     doc.detect_indent_and_line_ending();
 
     let id = doc.id();
diff --git a/helix-view/src/document.rs b/helix-view/src/document.rs
index a0d504407..84c92320c 100644
--- a/helix-view/src/document.rs
+++ b/helix-view/src/document.rs
@@ -683,9 +683,13 @@ pub fn set_language_by_language_id(
         &mut self,
         language_id: &str,
         config_loader: Arc<syntax::Loader>,
-    ) {
+    ) -> bool {
         let language_config = config_loader.language_config_for_language_id(language_id);
+        if language_config.is_none() {
+            return false;
+        }
         self.set_language(language_config, Some(config_loader));
+        true
     }
 
     /// Set the LSP.