diff --git a/Cargo.lock b/Cargo.lock
index 615825bd75..2e7997458e 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -4592,6 +4592,7 @@ dependencies = [
  "lsp",
  "parking_lot 0.11.2",
  "postage",
+ "pretty_assertions",
  "pulldown-cmark",
  "rand 0.8.5",
  "regex",
diff --git a/crates/project/Cargo.toml b/crates/project/Cargo.toml
index 949dbdf916..68dc57f614 100644
--- a/crates/project/Cargo.toml
+++ b/crates/project/Cargo.toml
@@ -57,6 +57,7 @@ thiserror = "1.0.29"
 toml = "0.5"
 
 [dev-dependencies]
+pretty_assertions = "1.3.0"
 client = { path = "../client", features = ["test-support"] }
 collections = { path = "../collections", features = ["test-support"] }
 db = { path = "../db", features = ["test-support"] }
diff --git a/crates/project/src/project_tests.rs b/crates/project/src/project_tests.rs
index 2f9f92af4e..ddcfed9dac 100644
--- a/crates/project/src/project_tests.rs
+++ b/crates/project/src/project_tests.rs
@@ -8,6 +8,7 @@ use language::{
     OffsetRangeExt, Point, ToPoint,
 };
 use lsp::Url;
+use pretty_assertions::assert_eq;
 use serde_json::json;
 use std::{cell::RefCell, os::unix, rc::Rc, task::Poll};
 use unindent::Unindent as _;
@@ -2846,7 +2847,7 @@ async fn test_grouped_diagnostics(cx: &mut gpui::TestAppContext) {
                 diagnostic: Diagnostic {
                     severity: DiagnosticSeverity::WARNING,
                     message: "error 1".to_string(),
-                    group_id: 0,
+                    group_id: 1,
                     is_primary: true,
                     ..Default::default()
                 }
@@ -2856,7 +2857,7 @@ async fn test_grouped_diagnostics(cx: &mut gpui::TestAppContext) {
                 diagnostic: Diagnostic {
                     severity: DiagnosticSeverity::HINT,
                     message: "error 1 hint 1".to_string(),
-                    group_id: 0,
+                    group_id: 1,
                     is_primary: false,
                     ..Default::default()
                 }
@@ -2866,7 +2867,7 @@ async fn test_grouped_diagnostics(cx: &mut gpui::TestAppContext) {
                 diagnostic: Diagnostic {
                     severity: DiagnosticSeverity::HINT,
                     message: "error 2 hint 1".to_string(),
-                    group_id: 1,
+                    group_id: 0,
                     is_primary: false,
                     ..Default::default()
                 }
@@ -2876,7 +2877,7 @@ async fn test_grouped_diagnostics(cx: &mut gpui::TestAppContext) {
                 diagnostic: Diagnostic {
                     severity: DiagnosticSeverity::HINT,
                     message: "error 2 hint 2".to_string(),
-                    group_id: 1,
+                    group_id: 0,
                     is_primary: false,
                     ..Default::default()
                 }
@@ -2886,7 +2887,7 @@ async fn test_grouped_diagnostics(cx: &mut gpui::TestAppContext) {
                 diagnostic: Diagnostic {
                     severity: DiagnosticSeverity::ERROR,
                     message: "error 2".to_string(),
-                    group_id: 1,
+                    group_id: 0,
                     is_primary: true,
                     ..Default::default()
                 }
@@ -2896,38 +2897,13 @@ async fn test_grouped_diagnostics(cx: &mut gpui::TestAppContext) {
 
     assert_eq!(
         buffer.diagnostic_group::<Point>(0).collect::<Vec<_>>(),
-        &[
-            DiagnosticEntry {
-                range: Point::new(1, 8)..Point::new(1, 9),
-                diagnostic: Diagnostic {
-                    severity: DiagnosticSeverity::WARNING,
-                    message: "error 1".to_string(),
-                    group_id: 0,
-                    is_primary: true,
-                    ..Default::default()
-                }
-            },
-            DiagnosticEntry {
-                range: Point::new(1, 8)..Point::new(1, 9),
-                diagnostic: Diagnostic {
-                    severity: DiagnosticSeverity::HINT,
-                    message: "error 1 hint 1".to_string(),
-                    group_id: 0,
-                    is_primary: false,
-                    ..Default::default()
-                }
-            },
-        ]
-    );
-    assert_eq!(
-        buffer.diagnostic_group::<Point>(1).collect::<Vec<_>>(),
         &[
             DiagnosticEntry {
                 range: Point::new(1, 13)..Point::new(1, 15),
                 diagnostic: Diagnostic {
                     severity: DiagnosticSeverity::HINT,
                     message: "error 2 hint 1".to_string(),
-                    group_id: 1,
+                    group_id: 0,
                     is_primary: false,
                     ..Default::default()
                 }
@@ -2937,7 +2913,7 @@ async fn test_grouped_diagnostics(cx: &mut gpui::TestAppContext) {
                 diagnostic: Diagnostic {
                     severity: DiagnosticSeverity::HINT,
                     message: "error 2 hint 2".to_string(),
-                    group_id: 1,
+                    group_id: 0,
                     is_primary: false,
                     ..Default::default()
                 }
@@ -2947,13 +2923,39 @@ async fn test_grouped_diagnostics(cx: &mut gpui::TestAppContext) {
                 diagnostic: Diagnostic {
                     severity: DiagnosticSeverity::ERROR,
                     message: "error 2".to_string(),
-                    group_id: 1,
+                    group_id: 0,
                     is_primary: true,
                     ..Default::default()
                 }
             }
         ]
     );
+
+    assert_eq!(
+        buffer.diagnostic_group::<Point>(1).collect::<Vec<_>>(),
+        &[
+            DiagnosticEntry {
+                range: Point::new(1, 8)..Point::new(1, 9),
+                diagnostic: Diagnostic {
+                    severity: DiagnosticSeverity::WARNING,
+                    message: "error 1".to_string(),
+                    group_id: 1,
+                    is_primary: true,
+                    ..Default::default()
+                }
+            },
+            DiagnosticEntry {
+                range: Point::new(1, 8)..Point::new(1, 9),
+                diagnostic: Diagnostic {
+                    severity: DiagnosticSeverity::HINT,
+                    message: "error 1 hint 1".to_string(),
+                    group_id: 1,
+                    is_primary: false,
+                    ..Default::default()
+                }
+            },
+        ]
+    );
 }
 
 #[gpui::test]