Shuffle code around to avoid an allocation

crates/rust-analyzer/src/global_state.rs

@@ -25,7 +25,7 @@ use crate::{
     main_loop::Task,
     mem_docs::MemDocs,
     op_queue::OpQueue,
-    reload::SourceRootConfig,
+    reload::{self, SourceRootConfig},
     thread_pool::TaskPool,
     to_proto::url_from_abs_path,
     Result,
@@ -175,7 +175,8 @@ impl GlobalState {
     pub(crate) fn process_changes(&mut self) -> bool {
         let _p = profile::span("GlobalState::process_changes");
         let mut fs_changes = Vec::new();
-        let mut has_fs_changes = false;
+        // A file was added or deleted
+        let mut has_structure_changes = false;
 
         let change = {
             let mut change = Change::new();
@@ -187,9 +188,13 @@ impl GlobalState {
 
             for file in changed_files {
                 if let Some(path) = vfs.file_path(file.file_id).as_path() {
-                    fs_changes.push((path.to_path_buf(), file.change_kind));
+                    let path = path.to_path_buf();
+                    if reload::should_refresh_for_change(&path, file.change_kind) {
+                        self.fetch_workspaces_queue.request_op();
+                    }
+                    fs_changes.push((path, file.change_kind));
                     if file.is_created_or_deleted() {
-                        has_fs_changes = true;
+                        has_structure_changes = true;
                     }
                 }
 
@@ -208,7 +213,7 @@ impl GlobalState {
                 };
                 change.change_file(file.file_id, text);
             }
-            if has_fs_changes {
+            if has_structure_changes {
                 let roots = self.source_root_config.partition(vfs);
                 change.set_roots(roots);
             }
@@ -216,7 +221,6 @@ impl GlobalState {
         };
 
         self.analysis_host.apply_change(change);
-        self.maybe_refresh(&fs_changes);
         true
     }
 

crates/rust-analyzer/src/main_loop.rs

@@ -21,7 +21,7 @@ use crate::{
     handlers, lsp_ext,
     lsp_utils::{apply_document_changes, is_cancelled, notification_is, Progress},
     mem_docs::DocumentData,
-    reload::{BuildDataProgress, ProjectWorkspaceProgress},
+    reload::{self, BuildDataProgress, ProjectWorkspaceProgress},
     Result,
 };
 
@@ -693,7 +693,9 @@ impl GlobalState {
                     flycheck.update();
                 }
                 if let Ok(abs_path) = from_proto::abs_path(&params.text_document.uri) {
-                    this.maybe_refresh(&[(abs_path, ChangeKind::Modify)]);
+                    if reload::should_refresh_for_change(&abs_path, ChangeKind::Modify) {
+                        this.fetch_workspaces_queue.request_op();
+                    }
                 }
                 Ok(())
             })?

crates/rust-analyzer/src/reload.rs

@@ -58,58 +58,6 @@ impl GlobalState {
             .raw_database_mut()
             .set_enable_proc_attr_macros(self.config.expand_proc_attr_macros());
     }
-    pub(crate) fn maybe_refresh(&mut self, changes: &[(AbsPathBuf, ChangeKind)]) {
-        if !changes.iter().any(|(path, kind)| is_interesting(path, *kind)) {
-            return;
-        }
-        tracing::info!(
-            "Requesting workspace reload because of the following changes: {}",
-            itertools::join(
-                changes
-                    .iter()
-                    .filter(|(path, kind)| is_interesting(path, *kind))
-                    .map(|(path, kind)| format!("{}: {:?}", path.display(), kind)),
-                ", "
-            )
-        );
-        self.fetch_workspaces_queue.request_op();
-
-        fn is_interesting(path: &AbsPath, change_kind: ChangeKind) -> bool {
-            const IMPLICIT_TARGET_FILES: &[&str] = &["build.rs", "src/main.rs", "src/lib.rs"];
-            const IMPLICIT_TARGET_DIRS: &[&str] = &["src/bin", "examples", "tests", "benches"];
-            let file_name = path.file_name().unwrap_or_default();
-
-            if file_name == "Cargo.toml" || file_name == "Cargo.lock" {
-                return true;
-            }
-            if change_kind == ChangeKind::Modify {
-                return false;
-            }
-            if path.extension().unwrap_or_default() != "rs" {
-                return false;
-            }
-            if IMPLICIT_TARGET_FILES.iter().any(|it| path.as_ref().ends_with(it)) {
-                return true;
-            }
-            let parent = match path.parent() {
-                Some(it) => it,
-                None => return false,
-            };
-            if IMPLICIT_TARGET_DIRS.iter().any(|it| parent.as_ref().ends_with(it)) {
-                return true;
-            }
-            if file_name == "main.rs" {
-                let grand_parent = match parent.parent() {
-                    Some(it) => it,
-                    None => return false,
-                };
-                if IMPLICIT_TARGET_DIRS.iter().any(|it| grand_parent.as_ref().ends_with(it)) {
-                    return true;
-                }
-            }
-            false
-        }
-    }
 
     pub(crate) fn current_status(&self) -> lsp_ext::ServerStatusParams {
         let mut status = lsp_ext::ServerStatusParams {
@@ -617,3 +565,39 @@ pub(crate) fn load_proc_macro(client: Option<&ProcMacroServer>, path: &AbsPath)
         }
     }
 }
+
+pub(crate) fn should_refresh_for_change(path: &AbsPath, change_kind: ChangeKind) -> bool {
+    const IMPLICIT_TARGET_FILES: &[&str] = &["build.rs", "src/main.rs", "src/lib.rs"];
+    const IMPLICIT_TARGET_DIRS: &[&str] = &["src/bin", "examples", "tests", "benches"];
+    let file_name = path.file_name().unwrap_or_default();
+
+    if file_name == "Cargo.toml" || file_name == "Cargo.lock" {
+        return true;
+    }
+    if change_kind == ChangeKind::Modify {
+        return false;
+    }
+    if path.extension().unwrap_or_default() != "rs" {
+        return false;
+    }
+    if IMPLICIT_TARGET_FILES.iter().any(|it| path.as_ref().ends_with(it)) {
+        return true;
+    }
+    let parent = match path.parent() {
+        Some(it) => it,
+        None => return false,
+    };
+    if IMPLICIT_TARGET_DIRS.iter().any(|it| parent.as_ref().ends_with(it)) {
+        return true;
+    }
+    if file_name == "main.rs" {
+        let grand_parent = match parent.parent() {
+            Some(it) => it,
+            None => return false,
+        };
+        if IMPLICIT_TARGET_DIRS.iter().any(|it| grand_parent.as_ref().ends_with(it)) {
+            return true;
+        }
+    }
+    false
+}