[nextest-runner] add TestInstanceId

This identifier is used as a sort key as well.

nextest-runner/src/list/test_list.rs

@@ -987,10 +987,14 @@ impl<'a> TestInstance<'a> {
         }
     }
 
-    /// Return a reasonable key for sorting. This is (binary ID, test name).
+    /// Return an identifier for test instances, including being able to sort
+    /// them.
     #[inline]
-    pub(crate) fn sort_key(&self) -> (&'a str, &'a str) {
-        ((self.suite_info.binary_id.as_str()), self.name)
+    pub(crate) fn id(&self) -> TestInstanceId<'a> {
+        TestInstanceId {
+            binary_id: &self.suite_info.binary_id,
+            test_name: self.name,
+        }
     }
 
     /// Returns the corresponding [`TestQuery`] for this `TestInstance`.
@@ -1052,6 +1056,18 @@ impl<'a> TestInstance<'a> {
     }
 }
 
+/// A key for identifying and sorting test instances.
+///
+/// Returned by [`TestInstance::id`].
+#[derive(Clone, Copy, Debug, Eq, PartialEq, Ord, PartialOrd)]
+pub(crate) struct TestInstanceId<'a> {
+    /// The binary ID.
+    pub binary_id: &'a RustBinaryId,
+
+    /// The name of the test.
+    pub test_name: &'a str,
+}
+
 /// Context required for test execution.
 #[derive(Clone, Debug)]
 pub struct TestExecuteContext<'a> {

nextest-runner/src/reporter/displayer.rs

@@ -1012,10 +1012,11 @@ impl<'a> TestReporterImpl<'a> {
                     // Sort the final outputs for a friendlier experience.
                     self.final_outputs
                         .sort_by_key(|(test_instance, final_output)| {
-                            // Use the final status level, reversed (i.e. failing tests are printed at the very end).
+                            // Use the final status level, reversed (i.e.
+                            // failing tests are printed at the very end).
                             (
                                 Reverse(final_output.final_status_level()),
-                                test_instance.sort_key(),
+                                test_instance.id(),
                             )
                         });