Reword EOF in macro arm message

src/libsyntax/ext/tt/macro_rules.rs

@@ -59,7 +59,10 @@ impl<'a> ParserAnyMacro<'a> {
                 }
                 let msg = &e.message[0];
                 e.message[0] = (
-                    msg.0.replace(", found `<eof>`", ", found the end of the macro arm"),
+                    format!(
+                        "macro expansion ends with an incomplete expression: {}",
+                        msg.0.replace(", found `<eof>`", ""),
+                    ),
                     msg.1,
                 );
             }

src/test/ui/editions/edition-keywords-2018-2015-parsing.stderr

@@ -22,7 +22,7 @@ error: no rules expected the token `async`
 LL |     r#async = consumes_async_raw!(async); //~ ERROR no rules expected the token `async`
    |                                   ^^^^^ no rules expected this token in macro call
 
-error: expected one of `move`, `|`, or `||`, found the end of the macro arm
+error: macro expansion ends with an incomplete expression: expected one of `move`, `|`, or `||`
   --> <::edition_kw_macro_2015::passes_ident macros>:1:25
    |
 LL | ( $ i : ident ) => ( $ i )

src/test/ui/editions/edition-keywords-2018-2018-parsing.stderr

@@ -22,7 +22,7 @@ error: no rules expected the token `async`
 LL |     r#async = consumes_async_raw!(async); //~ ERROR no rules expected the token `async`
    |                                   ^^^^^ no rules expected this token in macro call
 
-error: expected one of `move`, `|`, or `||`, found the end of the macro arm
+error: macro expansion ends with an incomplete expression: expected one of `move`, `|`, or `||`
   --> <::edition_kw_macro_2018::passes_ident macros>:1:25
    |
 LL | ( $ i : ident ) => ( $ i )

src/test/ui/macros/macro-in-expression-context-2.stderr

@@ -1,4 +1,4 @@
-error: expected expression, found the end of the macro arm
+error: macro expansion ends with an incomplete expression: expected expression
   --> $DIR/macro-in-expression-context-2.rs:5:16
    |
 LL | macro_rules! empty { () => () }