python: Re-land usage of source file path in toolchain picker (#31893)

This reverts commit 1e55e88c18.

Closes #ISSUE

Release Notes:

- Python toolchain selector now uses path to the closest pyproject.toml
as a basis for picking a toolchain. All files under the same
pyproject.toml (in filesystem hierarchy) will share a single virtual
environment. It is possible to have multiple Python virtual environments
selected for disjoint parts of the same project.

crates/language/src/language.rs

@@ -34,7 +34,7 @@ pub use highlight_map::HighlightMap;
 use http_client::HttpClient;
 pub use language_registry::{LanguageName, LoadedLanguage};
 use lsp::{CodeActionKind, InitializeParams, LanguageServerBinary, LanguageServerBinaryOptions};
-pub use manifest::{ManifestName, ManifestProvider, ManifestQuery};
+pub use manifest::{ManifestDelegate, ManifestName, ManifestProvider, ManifestQuery};
 use parking_lot::Mutex;
 use regex::Regex;
 use schemars::{
@@ -323,7 +323,6 @@ pub trait LspAdapterDelegate: Send + Sync {
     fn http_client(&self) -> Arc<dyn HttpClient>;
     fn worktree_id(&self) -> WorktreeId;
     fn worktree_root_path(&self) -> &Path;
-    fn exists(&self, path: &Path, is_dir: Option<bool>) -> bool;
     fn update_status(&self, language: LanguageServerName, status: BinaryStatus);
     fn registered_lsp_adapters(&self) -> Vec<Arc<dyn LspAdapter>>;
     async fn language_server_download_dir(&self, name: &LanguageServerName) -> Option<Arc<Path>>;

crates/language/src/manifest.rs

@@ -1,8 +1,7 @@
 use std::{borrow::Borrow, path::Path, sync::Arc};
 
 use gpui::SharedString;
-
-use crate::LspAdapterDelegate;
+use settings::WorktreeId;
 
 #[derive(Clone, Debug, PartialEq, Eq, Hash, PartialOrd, Ord)]
 pub struct ManifestName(SharedString);
@@ -39,10 +38,15 @@ pub struct ManifestQuery {
     /// Path to the file, relative to worktree root.
     pub path: Arc<Path>,
     pub depth: usize,
-    pub delegate: Arc<dyn LspAdapterDelegate>,
+    pub delegate: Arc<dyn ManifestDelegate>,
 }
 
 pub trait ManifestProvider {
     fn name(&self) -> ManifestName;
     fn search(&self, query: ManifestQuery) -> Option<Arc<Path>>;
 }
+
+pub trait ManifestDelegate: Send + Sync {
+    fn worktree_id(&self) -> WorktreeId;
+    fn exists(&self, path: &Path, is_dir: Option<bool>) -> bool;
+}

crates/language/src/toolchain.rs

@@ -14,7 +14,7 @@ use collections::HashMap;
 use gpui::{AsyncApp, SharedString};
 use settings::WorktreeId;
 
-use crate::LanguageName;
+use crate::{LanguageName, ManifestName};
 
 /// Represents a single toolchain.
 #[derive(Clone, Debug)]
@@ -44,10 +44,13 @@ pub trait ToolchainLister: Send + Sync {
     async fn list(
         &self,
         worktree_root: PathBuf,
+        subroot_relative_path: Option<Arc<Path>>,
         project_env: Option<HashMap<String, String>>,
     ) -> ToolchainList;
     // Returns a term which we should use in UI to refer to a toolchain.
     fn term(&self) -> SharedString;
+    /// Returns the name of the manifest file for this toolchain.
+    fn manifest_name(&self) -> ManifestName;
 }
 
 #[async_trait(?Send)]