diff options
| -rw-r--r-- | compiler/rustc_typeck/src/check/upvar.rs | 43 |
1 files changed, 31 insertions, 12 deletions
diff --git a/compiler/rustc_typeck/src/check/upvar.rs b/compiler/rustc_typeck/src/check/upvar.rs index 124076a889b..cd93cbbe965 100644 --- a/compiler/rustc_typeck/src/check/upvar.rs +++ b/compiler/rustc_typeck/src/check/upvar.rs @@ -479,7 +479,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { ); if !need_migrations.is_empty() { - let migrations_text = migration_suggestion_for_2229(self.tcx, &need_migrations); + let (migration_string, migrated_variables_concat) = + migration_suggestion_for_2229(self.tcx, &need_migrations); let local_def_id = closure_def_id.expect_local(); let closure_hir_id = self.tcx.hir().local_def_id_to_hir_id(local_def_id); @@ -495,15 +496,20 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { let (sugg, app) = match self.tcx.sess.source_map().span_to_snippet(closure_body_span) { Ok(s) => ( - format!("{{ {} {} }}", migrations_text, s), + format!("{{ {}; {} }}", migration_string, s), Applicability::MachineApplicable, ), - Err(_) => (migrations_text.clone(), Applicability::HasPlaceholders), + Err(_) => (migration_string.clone(), Applicability::HasPlaceholders), }; + let diagnostic_msg = format!( + "`{}` causes {} to be fully captured", + migration_string, migrated_variables_concat + ); + diagnostics_builder.span_suggestion( closure_body_span, - &format!("You can restore original behavior adding `{}` to the closure/generator", migrations_text), + &diagnostic_msg, sugg, app, ); @@ -1537,16 +1543,29 @@ fn should_do_migration_analysis(tcx: TyCtxt<'_>, closure_id: hir::HirId) -> bool !matches!(level, lint::Level::Allow) } -fn migration_suggestion_for_2229(tcx: TyCtxt<'_>, need_migrations: &Vec<hir::HirId>) -> String { - let need_migrations_strings = - need_migrations.iter().map(|v| format!("&{}", var_name(tcx, *v))).collect::<Vec<_>>(); - let migrations_list_concat = need_migrations_strings.join(", "); +/// Return a two string tuple (s1, s2) +/// - s1: Line of code that is needed for the migration: eg: `let _ = (&x, ...)`. +/// - s2: Comma separated names of the variables being migrated. +fn migration_suggestion_for_2229( + tcx: TyCtxt<'_>, + need_migrations: &Vec<hir::HirId>, +) -> (String, String) { + let need_migrations_variables = + need_migrations.iter().map(|v| var_name(tcx, *v)).collect::<Vec<_>>(); + + let migration_ref_concat = + need_migrations_variables.iter().map(|v| format!("&{}", v)).collect::<Vec<_>>().join(", "); - if 1 == need_migrations.len() { - format!("let _ = {};", migrations_list_concat) + let migration_string = if 1 == need_migrations.len() { + format!("let _ = {}", migration_ref_concat) } else { - format!("let _ = ({});", migrations_list_concat) - } + format!("let _ = ({})", migration_ref_concat) + }; + + let migrated_variables_concat = + need_migrations_variables.iter().map(|v| format!("`{}`", v)).collect::<Vec<_>>().join(", "); + + (migration_string, migrated_variables_concat) } /// Helper function to determine if we need to escalate CaptureKind from |