fix main.c so that we check the is_error flag and only show an error …

…message and backtrace if we have an error. This fixes TT #1907. Add two tests for the test cause provided by Coke++ to show that it does indeed have an exit code of 3, but that it produces no error output

frontend/parrot/main.c

@@ -186,13 +186,14 @@ show_last_error_and_exit(Parrot_PMC interp)
     Parrot_Int exit_code, is_error;
     Parrot_PMC exception;
 
-    if (!(Parrot_api_get_result(interp, &is_error, &exception, &exit_code, &errmsg) &&
-          Parrot_api_get_exception_backtrace(interp, exception, &backtrace))) {
+    if (!Parrot_api_get_result(interp, &is_error, &exception, &exit_code, &errmsg))
         exit(EXIT_FAILURE);
-    }
-
-    print_parrot_string(interp, stderr, errmsg, 1);
+    if (is_error) {
+        if (!Parrot_api_get_exception_backtrace(interp, exception, &backtrace))
+            exit(EXIT_FAILURE);
+        print_parrot_string(interp, stderr, errmsg, 1);
     print_parrot_string(interp, stderr, backtrace, 0);
+    }
 
     exit(exit_code);
 }

src/embed/api.c

@@ -65,7 +65,9 @@ Parrot_api_get_result(Parrot_PMC interp_pmc, ARGOUT(Parrot_Int *is_error),
         *errmsg = STRINGNULL;
     }
     else {
-        *is_error = !interp->exit_code;
+        STRING * const severity_str = Parrot_str_new(interp, "severity", 0);
+        INTVAL severity = VTABLE_get_integer_keyed_str(interp, *exception, severity_str);
+        *is_error = (severity != EXCEPT_exit);
         *errmsg = VTABLE_get_string(interp, *exception);
     }
     interp->final_exception = PMCNULL;

t/op/exit.t

@@ -6,7 +6,7 @@ use warnings;
 use lib qw( . lib ../lib ../../lib );
 
 use Test::More;
-use Parrot::Test tests => 7;
+use Parrot::Test tests => 9;
 
 =head1 NAME
 
@@ -72,6 +72,16 @@ pir_exit_code_is( <<'CODE', 2, "pir exit code isn't exception type" );
 .end
 CODE
 
+my $exit_3_snippet = <<'CODE';
+.sub main :main
+    exit 3
+.end
+CODE
+
+pir_exit_code_is($exit_3_snippet, 3, "exit 3 causes exit code 3");
+pir_error_output_like($exit_3_snippet, '/^\s*$/', "exit opcode causes no error message to print");
+
+
 # Local Variables:
 #   mode: cperl
 #   cperl-indent-level: 4