Fix a bunch of other low-hanging style lints (#36498)

- **Fix a bunch of low hanging style lints like unnecessary-return**
- **Fix single worktree violation**
- **And the rest**

Release Notes:

- N/A

crates/agent2/src/db.rs

@@ -184,7 +184,7 @@ impl DbThread {
 }
 
 pub static ZED_STATELESS: std::sync::LazyLock<bool> =
-    std::sync::LazyLock::new(|| std::env::var("ZED_STATELESS").map_or(false, |v| !v.is_empty()));
+    std::sync::LazyLock::new(|| std::env::var("ZED_STATELESS").is_ok_and(|v| !v.is_empty()));
 
 #[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
 pub enum DataType {

crates/agent2/src/tests/mod.rs

@@ -742,7 +742,7 @@ async fn expect_tool_call(events: &mut UnboundedReceiver<Result<ThreadEvent>>) -
         .expect("no tool call authorization event received")
         .unwrap();
     match event {
-        ThreadEvent::ToolCall(tool_call) => return tool_call,
+        ThreadEvent::ToolCall(tool_call) => tool_call,
         event => {
             panic!("Unexpected event {event:?}");
         }
@@ -758,9 +758,7 @@ async fn expect_tool_call_update_fields(
         .expect("no tool call authorization event received")
         .unwrap();
     match event {
-        ThreadEvent::ToolCallUpdate(acp_thread::ToolCallUpdate::UpdateFields(update)) => {
-            return update;
-        }
+        ThreadEvent::ToolCallUpdate(acp_thread::ToolCallUpdate::UpdateFields(update)) => update,
         event => {
             panic!("Unexpected event {event:?}");
         }

crates/agent2/src/thread.rs

@@ -1356,7 +1356,7 @@ impl Thread {
 
         // Ensure the last message ends in the current tool use
         let last_message = self.pending_message();
-        let push_new_tool_use = last_message.content.last_mut().map_or(true, |content| {
+        let push_new_tool_use = last_message.content.last_mut().is_none_or(|content| {
             if let AgentMessageContent::ToolUse(last_tool_use) = content {
                 if last_tool_use.id == tool_use.id {
                     *last_tool_use = tool_use.clone();
@@ -1408,7 +1408,7 @@ impl Thread {
             status: Some(acp::ToolCallStatus::InProgress),
             ..Default::default()
         });
-        let supports_images = self.model().map_or(false, |model| model.supports_images());
+        let supports_images = self.model().is_some_and(|model| model.supports_images());
         let tool_result = tool.run(tool_use.input, tool_event_stream, cx);
         log::info!("Running tool {}", tool_use.name);
         Some(cx.foreground_executor().spawn(async move {

crates/agent2/src/tools/read_file_tool.rs

@@ -175,7 +175,7 @@ impl AgentTool for ReadFileTool {
                 buffer
                     .file()
                     .as_ref()
-                    .map_or(true, |file| !file.disk_state().exists())
+                    .is_none_or(|file| !file.disk_state().exists())
             })? {
                 anyhow::bail!("{file_path} not found");
             }

crates/agent2/src/tools/terminal_tool.rs

@@ -271,7 +271,7 @@ fn working_dir(
     let project = project.read(cx);
     let cd = &input.cd;
 
-    if cd == "." || cd == "" {
+    if cd == "." || cd.is_empty() {
         // Accept "." or "" as meaning "the one worktree" if we only have one worktree.
         let mut worktrees = project.worktrees(cx);
 
@@ -296,10 +296,8 @@ fn working_dir(
             {
                 return Ok(Some(input_path.into()));
             }
-        } else {
-            if let Some(worktree) = project.worktree_for_root_name(cd, cx) {
-                return Ok(Some(worktree.read(cx).abs_path().to_path_buf()));
-            }
+        } else if let Some(worktree) = project.worktree_for_root_name(cd, cx) {
+            return Ok(Some(worktree.read(cx).abs_path().to_path_buf()));
         }
 
         anyhow::bail!("`cd` directory {cd:?} was not in any of the project's worktrees.");