// RUN: not FileCheck -check-prefix=FOO %s </dev/null 2>&1 | FileCheck -check-prefix=EMPTY-ERR %s
// RUN: not FileCheck -check-prefix=NOFOO %s </dev/null 2>&1 | FileCheck -check-prefix=EMPTY-ERR %s
// RUN: not FileCheck -check-prefix=FOO -allow-empty %s </dev/null 2>&1 | FileCheck -check-prefix=NO-EMPTY-ERR -check-prefix=NOT-FOUND %s
// RUN: FileCheck -check-prefix=NOFOO -allow-empty %s </dev/null 2>&1 | FileCheck -allow-empty -check-prefix=NO-EMPTY-ERR %s

; FOO: foo
; NOFOO-NOT: foo

; EMPTY-ERR: FileCheck error: '-' is empty.
; EMPTY-ERR-NEXT: FileCheck command line: {{.*}}FileCheck{{.*}}-check-prefix={{.*}}FOO {{.*}}check-empty.txt
; NO-EMPTY-ERR-NOT: FileCheck error: '-' is empty.
; NOT-FOUND: error: expected string not found in input