Refactor language config loading (#1658)

helix-core/src/config.rs

@@ -0,0 +1,33 @@
+use crate::merge_toml_values;
+
+/// Default bultin-in languages.toml.
+pub fn default_lang_config() -> toml::Value {
+    toml::from_slice(include_bytes!("../../languages.toml"))
+        .expect("Could not parse bultin-in languages.toml to valid toml")
+}
+
+/// User configured languages.toml file, merged with the default config.
+pub fn user_lang_config() -> Result<toml::Value, toml::de::Error> {
+    let def_lang_conf = default_lang_config();
+    let data = std::fs::read(crate::config_dir().join("languages.toml"));
+    let user_lang_conf = match data {
+        Ok(raw) => {
+            let value = toml::from_slice(&raw)?;
+            merge_toml_values(def_lang_conf, value)
+        }
+        Err(_) => def_lang_conf,
+    };
+
+    Ok(user_lang_conf)
+}
+
+/// Syntax configuration loader based on built-in languages.toml.
+pub fn default_syntax_loader() -> crate::syntax::Configuration {
+    default_lang_config()
+        .try_into()
+        .expect("Could not serialize built-in language.toml")
+}
+/// Syntax configuration loader based on user configured languages.toml.
+pub fn user_syntax_loader() -> Result<crate::syntax::Configuration, toml::de::Error> {
+    user_lang_config()?.try_into()
+}

helix-core/src/lib.rs

@@ -3,6 +3,7 @@ pub use encoding_rs as encoding;
 pub mod auto_pairs;
 pub mod chars;
 pub mod comment;
+pub mod config;
 pub mod diagnostic;
 pub mod diff;
 pub mod graphemes;

helix-term/src/application.rs

@@ -1,4 +1,7 @@
-use helix_core::{merge_toml_values, pos_at_coords, syntax, Selection};
+use helix_core::{
+    config::{default_syntax_loader, user_syntax_loader},
+    pos_at_coords, syntax, Selection,
+};
 use helix_dap::{self as dap, Payload, Request};
 use helix_lsp::{lsp, util::lsp_pos_to_pos, LspProgressMap};
 use helix_view::{editor::Breakpoint, theme, Editor};
@@ -69,21 +72,6 @@ impl Application {
             std::sync::Arc::new(theme::Loader::new(&conf_dir, &helix_core::runtime_dir()));
 
         // load default and user config, and merge both
-        let builtin_err_msg =
-            "Could not parse built-in languages.toml, something must be very wrong";
-        let def_lang_conf: toml::Value =
-            toml::from_slice(include_bytes!("../../languages.toml")).expect(builtin_err_msg);
-        let def_syn_loader_conf: helix_core::syntax::Configuration =
-            def_lang_conf.clone().try_into().expect(builtin_err_msg);
-        let user_lang_conf = std::fs::read(conf_dir.join("languages.toml"))
-            .ok()
-            .map(|raw| toml::from_slice(&raw));
-        let lang_conf = match user_lang_conf {
-            Some(Ok(value)) => Ok(merge_toml_values(def_lang_conf, value)),
-            Some(err @ Err(_)) => err,
-            None => Ok(def_lang_conf),
-        };
-
         let true_color = config.editor.true_color || crate::true_color();
         let theme = config
             .theme
@@ -106,16 +94,14 @@ impl Application {
                 }
             });
 
-        let syn_loader_conf: helix_core::syntax::Configuration = lang_conf
-            .and_then(|conf| conf.try_into())
-            .unwrap_or_else(|err| {
-                eprintln!("Bad language config: {}", err);
-                eprintln!("Press <ENTER> to continue with default language config");
-                use std::io::Read;
-                // This waits for an enter press.
-                let _ = std::io::stdin().read(&mut []);
-                def_syn_loader_conf
-            });
+        let syn_loader_conf = user_syntax_loader().unwrap_or_else(|err| {
+            eprintln!("Bad language config: {}", err);
+            eprintln!("Press <ENTER> to continue with default language config");
+            use std::io::Read;
+            // This waits for an enter press.
+            let _ = std::io::stdin().read(&mut []);
+            default_syntax_loader()
+        });
         let syn_loader = std::sync::Arc::new(syntax::Loader::new(syn_loader_conf));
 
         let mut editor = Editor::new(