FileCheck: fix a bug with multiple --check-prefix options. Similar to r194565

Summary:
Directives are being ignored, when they occur between a partial-word false
match and any match on another prefix.

For example, with FOO and BAR prefixes:
   _FOO
   FOO: foo
   BAR: bar
FileCheck incorrectly matches:
   fog
   bar

This happens because FOO falsely matched as a partial word at '_FOO' and was
ignored while BAR matched at 'BAR:'. The match of BAR is incorrectly returned
as the 'first match' causing the FOO directive to be discarded.

Fixed this the same way as r194565 (D2166) did for a similar test case.
The partial-word false match should be counted as a match for the purposes of
finding the first match of a prefix, but should be returned as a false match
using CheckTy::CheckNone so that it isn't treated as a directive.

Fixes PR17995

Reviewers: samsonov, arsenm

Reviewed By: samsonov

CC: llvm-commits

Differential Revision: http://llvm-reviews.chandlerc.com/D2228

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195248 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 10 insertions, 0 deletions

diff --git a/test/FileCheck/check-multiple-prefixes-nomatch-2.txt b/test/FileCheck/check-multiple-prefixes-nomatch-2.txt
new file mode 100644
index 0000000000..a1dc3d87b0
--- /dev/null
+++ b/test/FileCheck/check-multiple-prefixes-nomatch-2.txt
@@ -0,0 +1,10 @@
+; RUN: not FileCheck -input-file %s %s -check-prefix=FOO -check-prefix=BAR 2>&1 | FileCheck %s
+
+fog
+bar
+; _FOO not a valid check-line
+; FOO: fo{{o}}
+; BAR: ba{{r}}
+
+; CHECK: {{error: expected string not found in input}}
+; CHECK-NEXT: {{F}}OO: fo{{[{][{]o[}][}]}}