Revert "Stop generating in the Agent panel when the user edits a previous message (#29915)" (#30092)

This reverts commit ce053c9bff.

Closes #ISSUE

Release Notes:

- N/A

crates/agent/src/active_thread.rs

@@ -1282,9 +1282,6 @@ impl ActiveThread {
             return;
         };
 
-        // Cancel any ongoing streaming when user starts editing a previous message
-        self.cancel_last_completion(window, cx);
-
         let editor = crate::message_editor::create_editor(
             self.workspace.clone(),
             self.context_store.downgrade(),
@@ -3583,152 +3580,3 @@ fn open_editor_at_position(
         }
     })
 }
-
-#[cfg(test)]
-mod tests {
-    use assistant_tool::{ToolRegistry, ToolWorkingSet};
-    use editor::EditorSettings;
-    use fs::FakeFs;
-    use gpui::{TestAppContext, VisualTestContext};
-    use language_model::{LanguageModel, fake_provider::FakeLanguageModel};
-    use project::Project;
-    use prompt_store::PromptBuilder;
-    use serde_json::json;
-    use settings::SettingsStore;
-    use util::path;
-
-    use crate::{ContextLoadResult, thread_store};
-
-    use super::*;
-
-    #[gpui::test]
-    async fn test_current_completion_cancelled_when_message_edited(cx: &mut TestAppContext) {
-        init_test_settings(cx);
-
-        let project = create_test_project(
-            cx,
-            json!({"code.rs": "fn main() {\n    println!(\"Hello, world!\");\n}"}),
-        )
-        .await;
-
-        let (cx, active_thread, thread, model) = setup_test_environment(cx, project.clone()).await;
-
-        // Insert user message without any context (empty context vector)
-        let message = thread.update(cx, |thread, cx| {
-            let message_id = thread.insert_user_message(
-                "What is the best way to learn Rust?",
-                ContextLoadResult::default(),
-                None,
-                vec![],
-                cx,
-            );
-            thread
-                .message(message_id)
-                .expect("message should exist")
-                .clone()
-        });
-
-        // Stream response to user message
-        thread.update(cx, |thread, cx| {
-            let request = thread.to_completion_request(model.clone(), cx);
-            thread.stream_completion(request, model, cx.active_window(), cx)
-        });
-        let generating = thread.update(cx, |thread, _cx| thread.is_generating());
-        assert!(generating, "There should be one pending completion");
-
-        // Edit the previous message
-        active_thread.update_in(cx, |active_thread, window, cx| {
-            active_thread.start_editing_message(message.id, &message.segments, window, cx);
-        });
-
-        // Check that the stream was cancelled
-        let generating = thread.update(cx, |thread, _cx| thread.is_generating());
-        assert!(!generating, "The completion should have been cancelled");
-    }
-
-    fn init_test_settings(cx: &mut TestAppContext) {
-        cx.update(|cx| {
-            let settings_store = SettingsStore::test(cx);
-            cx.set_global(settings_store);
-            language::init(cx);
-            Project::init_settings(cx);
-            AssistantSettings::register(cx);
-            prompt_store::init(cx);
-            thread_store::init(cx);
-            workspace::init_settings(cx);
-            language_model::init_settings(cx);
-            ThemeSettings::register(cx);
-            EditorSettings::register(cx);
-            ToolRegistry::default_global(cx);
-        });
-    }
-
-    // Helper to create a test project with test files
-    async fn create_test_project(
-        cx: &mut TestAppContext,
-        files: serde_json::Value,
-    ) -> Entity<Project> {
-        let fs = FakeFs::new(cx.executor());
-        fs.insert_tree(path!("/test"), files).await;
-        Project::test(fs, [path!("/test").as_ref()], cx).await
-    }
-
-    async fn setup_test_environment(
-        cx: &mut TestAppContext,
-        project: Entity<Project>,
-    ) -> (
-        &mut VisualTestContext,
-        Entity<ActiveThread>,
-        Entity<Thread>,
-        Arc<dyn LanguageModel>,
-    ) {
-        let (workspace, cx) =
-            cx.add_window_view(|window, cx| Workspace::test_new(project.clone(), window, cx));
-
-        let prompt_builder = Arc::new(PromptBuilder::new(None).unwrap());
-        let thread_store = cx
-            .update(|_, cx| {
-                ThreadStore::load(
-                    project.clone(),
-                    cx.new(|_| ToolWorkingSet::default()),
-                    None,
-                    prompt_builder.clone(),
-                    cx,
-                )
-            })
-            .await
-            .unwrap();
-        let text_thread_store = cx
-            .update(|_, cx| {
-                TextThreadStore::new(project.clone(), prompt_builder, Default::default(), cx)
-            })
-            .await
-            .unwrap();
-
-        let thread = thread_store.update(cx, |store, cx| store.create_thread(cx));
-        let context_store = cx.new(|_cx| ContextStore::new(project.downgrade(), None));
-
-        let model = FakeLanguageModel::default();
-        let model: Arc<dyn LanguageModel> = Arc::new(model);
-
-        let language_registry = LanguageRegistry::new(cx.executor());
-        let language_registry = Arc::new(language_registry);
-
-        let active_thread = cx.update(|window, cx| {
-            cx.new(|cx| {
-                ActiveThread::new(
-                    thread.clone(),
-                    thread_store.clone(),
-                    text_thread_store.clone(),
-                    context_store.clone(),
-                    language_registry.clone(),
-                    workspace.downgrade(),
-                    window,
-                    cx,
-                )
-            })
-        });
-
-        (cx, active_thread, thread, model)
-    }
-}