Set transaction group interval to ZERO by default in tests

We were seeing non-deterministic behavior in randomized tests when
generating backtraces took enough time to cause transactions to group
in some cases, but not group in others.

Tests will need to explicitly opt into grouping if they want it by
setting the interval explicitly. We have tests in the text module that
currently test the history grouping explicitly, but I'm not sure
it's needed elsewhere.

crates/client/src/client.rs

@@ -851,7 +851,6 @@ impl Client {
             })
             .detach();
 
-        let t0 = Instant::now();
         let this = self.clone();
         let cx = cx.clone();
         cx.foreground()
@@ -868,12 +867,7 @@ impl Client {
                         }
                     }
                     Err(err) => {
-                        // TODO - remove. Make the test's non-determinism more apparent by
-                        // only sometimes formatting this stack trace.
-                        if Instant::now().duration_since(t0).as_nanos() % 2 == 0 {
-                            log::error!("connection error: {:?}", err);
-                        }
-
+                        log::error!("connection error: {:?}", err);
                         this.set_status(Status::ConnectionLost, &cx);
                     }
                 }

crates/collab/src/tests/randomized_integration_tests.rs

@@ -17,7 +17,7 @@ use project::{search::SearchQuery, Project};
 use rand::prelude::*;
 use std::{env, path::PathBuf, sync::Arc};
 
-#[gpui::test(iterations = 100, detect_nondeterminism = true)]
+#[gpui::test(iterations = 100)]
 async fn test_random_collaboration(
     cx: &mut TestAppContext,
     deterministic: Arc<Deterministic>,

crates/gpui/src/executor.rs

@@ -198,9 +198,7 @@ impl Deterministic {
         let unparker = self.parker.lock().unparker();
         let (runnable, task) = async_task::spawn_local(future, move |runnable| {
             let mut state = state.lock();
-            state
-                .poll_history
-                .push(ExecutorEvent::EnqueuRunnable { id });
+            state.push_to_history(ExecutorEvent::EnqueuRunnable { id });
             state
                 .scheduled_from_foreground
                 .entry(cx_id)

crates/text/src/tests.rs

@@ -45,7 +45,7 @@ fn test_random_edits(mut rng: StdRng) {
     let mut buffer = Buffer::new(0, 0, reference_string.clone());
     LineEnding::normalize(&mut reference_string);
 
-    buffer.history.group_interval = Duration::from_millis(rng.gen_range(0..=200));
+    buffer.set_group_interval(Duration::from_millis(rng.gen_range(0..=200)));
     let mut buffer_versions = Vec::new();
     log::info!(
         "buffer text {:?}, version: {:?}",
@@ -488,7 +488,7 @@ fn test_anchors_at_start_and_end() {
 fn test_undo_redo() {
     let mut buffer = Buffer::new(0, 0, "1234".into());
     // Set group interval to zero so as to not group edits in the undo stack.
-    buffer.history.group_interval = Duration::from_secs(0);
+    buffer.set_group_interval(Duration::from_secs(0));
 
     buffer.edit([(1..1, "abx")]);
     buffer.edit([(3..4, "yzef")]);
@@ -524,6 +524,7 @@ fn test_undo_redo() {
 fn test_history() {
     let mut now = Instant::now();
     let mut buffer = Buffer::new(0, 0, "123456".into());
+    buffer.set_group_interval(Duration::from_millis(300));
 
     let transaction_1 = buffer.start_transaction_at(now).unwrap();
     buffer.edit([(2..4, "cd")]);
@@ -535,7 +536,7 @@ fn test_history() {
     buffer.end_transaction_at(now).unwrap();
     assert_eq!(buffer.text(), "12cde6");
 
-    now += buffer.history.group_interval + Duration::from_millis(1);
+    now += buffer.transaction_group_interval() + Duration::from_millis(1);
     buffer.start_transaction_at(now);
     buffer.edit([(0..1, "a")]);
     buffer.edit([(1..1, "b")]);

crates/text/src/text.rs

@@ -115,6 +115,10 @@ impl History {
             undo_stack: Vec::new(),
             redo_stack: Vec::new(),
             transaction_depth: 0,
+            // Don't group transactions in tests unless we opt in, because it's a footgun.
+            #[cfg(any(test, feature = "test-support"))]
+            group_interval: Duration::ZERO,
+            #[cfg(not(any(test, feature = "test-support")))]
             group_interval: Duration::from_millis(300),
         }
     }