Plumb through check_old_skool for expected/found

Author: Jonathan Turner

src/librustc/infer/error_reporting.rs

@@ -90,7 +90,7 @@ use std::cell::{Cell, RefCell};
 use std::char::from_u32;
 use std::fmt;
 use syntax::ast;
-use syntax::errors::DiagnosticBuilder;
+use syntax::errors::{DiagnosticBuilder, check_old_skool};
 use syntax::codemap::{self, Pos, Span};
 use syntax::parse::token;
 use syntax::ptr::P;
@@ -554,7 +554,7 @@ impl<'a, 'tcx> ErrorReporting<'tcx> for InferCtxt<'a, 'tcx> {
                                        "{}",
                                        trace.origin);
 
-        if !is_simple_error {
+        if !is_simple_error || check_old_skool() {
             err = err.note_expected_found(&"type", &expected, &found);
         }
 

src/libsyntax/errors/mod.rs

@@ -691,13 +691,13 @@ pub fn expect<T, M>(diag: &Handler, opt: Option<T>, msg: M) -> T where
 ///
 /// FIXME(#33240)
 #[cfg(not(test))]
-fn check_old_skool() -> bool {
+pub fn check_old_skool() -> bool {
     use std::env;
     env::var("RUST_NEW_ERROR_FORMAT").is_err()
 }
 
 /// For unit tests, use the new format.
 #[cfg(test)]
-fn check_old_skool() -> bool {
+pub fn check_old_skool() -> bool {
     false
 }