feat: Add editorconfig support

Fixes #8534

crates/language/Cargo.toml

@@ -30,6 +30,7 @@ async-trait.workspace = true
 async-watch.workspace = true
 clock.workspace = true
 collections.workspace = true
+ec4rs = "1.1"
 futures.workspace = true
 fuzzy.workspace = true
 git.workspace = true

crates/language/src/buffer.rs

@@ -2624,11 +2624,7 @@ impl BufferSnapshot {
     }
 
     /// Returns the settings for the language at the given location.
-    pub fn settings_at<'a, D: ToOffset>(
-        &self,
-        position: D,
-        cx: &'a AppContext,
-    ) -> &'a LanguageSettings {
+    pub fn settings_at<D: ToOffset>(&self, position: D, cx: &AppContext) -> LanguageSettings {
         language_settings(self.language_at(position), self.file.as_ref(), cx)
     }
 

crates/language/src/language_settings.rs

@@ -4,6 +4,7 @@ use crate::{File, Language, LanguageServerName};
 use anyhow::Result;
 use collections::{HashMap, HashSet};
 use core::slice;
+use ec4rs::property::{FinalNewline, IndentSize, IndentStyle, TabWidth, TrimTrailingWs};
 use globset::{Glob, GlobMatcher, GlobSet, GlobSetBuilder};
 use gpui::AppContext;
 use itertools::{Either, Itertools};
@@ -35,13 +36,75 @@ pub fn init(cx: &mut AppContext) {
 }
 
 /// Returns the settings for the specified language from the provided file.
-pub fn language_settings<'a>(
+pub fn language_settings(
     language: Option<&Arc<Language>>,
     file: Option<&Arc<dyn File>>,
-    cx: &'a AppContext,
-) -> &'a LanguageSettings {
+    cx: &AppContext,
+) -> LanguageSettings {
     let language_name = language.map(|l| l.name());
-    all_language_settings(file, cx).language(language_name.as_deref())
+    let mut settings = all_language_settings(file, cx)
+        .language(language_name.as_deref())
+        .clone();
+    let path = file
+        .and_then(|f| f.as_local())
+        .map(|f| f.abs_path(cx))
+        .unwrap_or_else(|| std::path::PathBuf::new());
+    let mut cfg = ec4rs::properties_of(path).unwrap();
+    cfg.use_fallbacks();
+    let editor_config_content = LanguageSettingsContent {
+        tab_size: cfg
+            .get::<IndentSize>()
+            .map(|v| match v {
+                IndentSize::Value(u) => NonZeroU32::new(u as u32),
+                IndentSize::UseTabWidth => cfg
+                    .get::<TabWidth>()
+                    .map(|w| match w {
+                        TabWidth::Value(u) => NonZeroU32::new(u as u32),
+                    })
+                    .ok()
+                    .flatten(),
+            })
+            .ok()
+            .flatten(),
+        hard_tabs: cfg
+            .get::<IndentStyle>()
+            .map(|v| v.eq(&IndentStyle::Tabs))
+            .ok(),
+        soft_wrap: None,
+        preferred_line_length: None,
+        show_wrap_guides: None,
+        wrap_guides: None,
+        format_on_save: None,
+        remove_trailing_whitespace_on_save: cfg
+            .get::<TrimTrailingWs>()
+            .map(|v| match v {
+                TrimTrailingWs::Value(b) => b,
+            })
+            .ok(),
+        ensure_final_newline_on_save: cfg
+            .get::<FinalNewline>()
+            .map(|v| match v {
+                FinalNewline::Value(b) => b,
+            })
+            .ok(),
+        formatter: None,
+        prettier: None,
+        enable_language_server: None,
+        show_whitespaces: None,
+        extend_comment_on_newline: None,
+        inlay_hints: None,
+        use_autoclose: None,
+        code_actions_on_format: None,
+        indent_guides: None,
+        language_servers: None,
+        show_inline_completions: None,
+        use_auto_surround: None,
+        always_treat_brackets_as_autoclosed: None,
+        linked_edits: None,
+        tasks: None,
+    };
+    merge_settings(&mut settings, &editor_config_content);
+    settings
 }
 
 /// Returns the settings for all languages from the provided file.

crates/multi_buffer/src/multi_buffer.rs

@@ -1721,11 +1721,7 @@ impl MultiBuffer {
             .and_then(|(buffer, offset, _)| buffer.read(cx).language_at(offset))
     }
 
-    pub fn settings_at<'a, T: ToOffset>(
-        &self,
-        point: T,
-        cx: &'a AppContext,
-    ) -> &'a LanguageSettings {
+    pub fn settings_at<T: ToOffset>(&self, point: T, cx: &AppContext) -> LanguageSettings {
         let mut language = None;
         let mut file = None;
         if let Some((buffer, offset, _)) = self.point_to_buffer_offset(point, cx) {
@@ -3461,7 +3457,7 @@ impl MultiBufferSnapshot {
         &'a self,
         point: T,
         cx: &'a AppContext,
-    ) -> &'a LanguageSettings {
+    ) -> LanguageSettings {
         let mut language = None;
         let mut file = None;
         if let Some((buffer, offset)) = self.point_to_buffer_offset(point) {

crates/project/src/lsp_command.rs

@@ -2278,7 +2278,7 @@ impl LspCommand for OnTypeFormatting {
             .await?;
 
         let options = buffer.update(&mut cx, |buffer, cx| {
-            lsp_formatting_options(language_settings(buffer.language(), buffer.file(), cx))
+            lsp_formatting_options(&language_settings(buffer.language(), buffer.file(), cx))
         })?;
 
         Ok(Self {

crates/project/src/project.rs

@@ -7029,7 +7029,7 @@ impl Project {
         cx: &mut ModelContext<Self>,
     ) -> Task<Result<Option<Transaction>>> {
         let options = buffer.update(cx, |buffer, cx| {
-            lsp_command::lsp_formatting_options(language_settings(
+            lsp_command::lsp_formatting_options(&language_settings(
                 buffer.language_at(position).as_ref(),
                 buffer.file(),
                 cx,

crates/project/src/project_tests.rs

@@ -93,38 +93,46 @@ async fn test_symlinks(cx: &mut gpui::TestAppContext) {
 #[gpui::test]
 async fn test_managing_project_specific_settings(cx: &mut gpui::TestAppContext) {
     init_test(cx);
-
-    let fs = FakeFs::new(cx.executor());
-    fs.insert_tree(
-        "/the-root",
-        json!({
-            ".zed": {
-                "settings.json": r#"{ "tab_size": 8 }"#,
-                "tasks.json": r#"[{
+    let dir = temp_tree(json!({
+        ".zed": {
+            "settings.json": r#"{ "tab_size": 8, "ensure_final_newline_on_save": false }"#,
+            "tasks.json": r#"[{
                     "label": "cargo check",
                     "command": "cargo",
                     "args": ["check", "--all"]
                 },]"#,
-            },
-            "a": {
-                "a.rs": "fn a() {\n    A\n}"
-            },
-            "b": {
-                ".zed": {
-                    "settings.json": r#"{ "tab_size": 2 }"#,
-                    "tasks.json": r#"[{
+        },
+        ".editorconfig": r#"root = true
+			   [*.rs]
+			   insert_final_newline = true
+			"#,
+        "a": {
+            "a.rs": "fn a() {\n    A\n}"
+        },
+        "b": {
+            ".zed": {
+                "settings.json": r#"{ "tab_size": 2 }"#,
+                "tasks.json": r#"[{
                         "label": "cargo check",
                         "command": "cargo",
                         "args": ["check"]
                     },]"#,
-                },
-                "b.rs": "fn b() {\n  B\n}"
-            }
-        }),
-    )
-    .await;
+            },
+            "b.rs": "fn b() {\n  B\n}"
+        },
+        "c": {
+            "c.rs": "fn c() {\n  C\n}",
+            ".editorconfig": r#"[*.rs]
+                   indent_size = 4
+                "#,
+        }
+    }));
 
-    let project = Project::test(fs.clone(), ["/the-root".as_ref()], cx).await;
+    let path = dir.path().as_ref();
+    let fs = FakeFs::new(cx.executor());
+    fs.insert_tree_from_real_fs(path, path).await;
+
+    let project = Project::test(fs.clone(), [path], cx).await;
     let worktree = project.update(cx, |project, cx| project.worktrees(cx).next().unwrap());
     let task_context = TaskContext::default();
 
@@ -136,7 +144,7 @@ async fn test_managing_project_specific_settings(cx: &mut gpui::TestAppContext)
     });
     let global_task_source_kind = TaskSourceKind::Worktree {
         id: worktree_id,
-        abs_path: PathBuf::from("/the-root/.zed/tasks.json"),
+        abs_path: PathBuf::from(format!("{}/.zed/tasks.json", path.display())),
         id_base: "local_tasks_for_worktree".into(),
     };
 
@@ -194,7 +202,7 @@ async fn test_managing_project_specific_settings(cx: &mut gpui::TestAppContext)
             (
                 TaskSourceKind::Worktree {
                     id: worktree_id,
-                    abs_path: PathBuf::from("/the-root/b/.zed/tasks.json"),
+                    abs_path: PathBuf::from(format!("{}/b/.zed/tasks.json", path.display())),
                     id_base: "local_tasks_for_worktree".into(),
                 },
                 "cargo check".to_string(),
@@ -235,7 +243,10 @@ async fn test_managing_project_specific_settings(cx: &mut gpui::TestAppContext)
     cx.update(|cx| {
         project.update(cx, |project, cx| {
             project.task_inventory().update(cx, |inventory, cx| {
-                inventory.remove_local_static_source(Path::new("/the-root/.zed/tasks.json"));
+                inventory.remove_local_static_source(&PathBuf::from(format!(
+                    "{}/.zed/tasks.json",
+                    path.display()
+                )));
                 inventory.add_source(
                     global_task_source_kind.clone(),
                     |tx, cx| StaticSource::new(TrackedFile::new(rx, tx, cx)),
@@ -267,7 +278,7 @@ async fn test_managing_project_specific_settings(cx: &mut gpui::TestAppContext)
             (
                 TaskSourceKind::Worktree {
                     id: worktree_id,
-                    abs_path: PathBuf::from("/the-root/.zed/tasks.json"),
+                    abs_path: PathBuf::from(format!("{}/.zed/tasks.json", path.display())),
                     id_base: "local_tasks_for_worktree".into(),
                 },
                 "cargo check".to_string(),
@@ -284,7 +295,7 @@ async fn test_managing_project_specific_settings(cx: &mut gpui::TestAppContext)
             (
                 TaskSourceKind::Worktree {
                     id: worktree_id,
-                    abs_path: PathBuf::from("/the-root/b/.zed/tasks.json"),
+                    abs_path: PathBuf::from(format!("{}/b/.zed/tasks.json", path.display())),
                     id_base: "local_tasks_for_worktree".into(),
                 },
                 "cargo check".to_string(),