Adjust comments

src/cargo/core/compiler/future_incompat.rs

@@ -254,9 +254,9 @@ fn render_report(per_package_reports: &[FutureIncompatReportPackage]) -> BTreeMa
     report
 }
 
-// Returns a pair (compatible_updates, incompatible_updates),
-// of semver-compatible and semver-incompatible update versions,
-// respectively.
+/// Returns a user-readable message explaining which of
+/// the packages in `package_ids` have updates available.
+/// This is best-effort - if an error occurs, `None` will be returned.
 fn get_updates(ws: &Workspace<'_>, package_ids: &BTreeSet<PackageId>) -> Option<String> {
     // This in general ignores all errors since this is opportunistic.
     let _lock = ws.config().acquire_package_cache_lock().ok()?;
@@ -312,7 +312,10 @@ fn get_updates(ws: &Workspace<'_>, package_ids: &BTreeSet<PackageId>) -> Option<
     Some(updates)
 }
 
-pub fn render_message(
+/// Writes a future-incompat report to disk, using the per-package
+/// reports gathered during the build. If requested by the user,
+/// a message is also displayed in the build output.
+pub fn save_and_display_report(
     bcx: &BuildContext<'_, '_>,
     per_package_future_incompat_reports: &[FutureIncompatReportPackage],
 ) {

src/cargo/core/compiler/job_queue.rs

@@ -871,7 +871,7 @@ impl<'cfg> DrainState<'cfg> {
             if !cx.bcx.build_config.build_plan {
                 // It doesn't really matter if this fails.
                 drop(cx.bcx.config.shell().status("Finished", message));
-                future_incompat::render_message(cx.bcx, &self.per_package_future_incompat_reports);
+                future_incompat::save_and_display_report(cx.bcx, &self.per_package_future_incompat_reports);
             }
 
             None

tests/testsuite/future_incompat_report.rs

@@ -269,7 +269,6 @@ fn test_multi_crate() {
         .exec_with_output()
         .unwrap();
     let output = std::str::from_utf8(&output.stdout).unwrap();
-    //if true { panic!("Got output: \n{}", output) }
     assert!(output.starts_with("The following warnings were discovered"));
     let mut lines = output
         .lines()