[FileCheck] Implement --ignore-case option.

The FileCheck utility is enhanced to support a `--ignore-case`
option. This is useful in cases where the output of Unix tools
differs in case (e.g. case not specified by Posix).

Reviewers: Bigcheese, jakehehrlich, rupprecht, espindola, alexshap, jhenderson, MaskRay

Differential Revision: https://reviews.llvm.org/D68146

llvm-svn: 374538

1 files changed, 7 insertions, 2 deletions

diff --git a/llvm/lib/Support/FileCheck.cpp b/llvm/lib/Support/FileCheck.cpp
index c3f537b3524..841e406a7b6 100644
--- a/llvm/lib/Support/FileCheck.cpp
+++ b/llvm/lib/Support/FileCheck.cpp
@@ -320,6 +320,7 @@ bool FileCheckPattern::parsePattern(StringRef PatternStr, StringRef Prefix,
                                     SourceMgr &SM,
                                     const FileCheckRequest &Req) {
   bool MatchFullLinesHere = Req.MatchFullLines && CheckTy != Check::CheckNot;
+  IgnoreCase = Req.IgnoreCase;
 
   PatternLoc = SMLoc::getFromPointer(PatternStr.data());
 
@@ -619,7 +620,8 @@ Expected<size_t> FileCheckPattern::match(StringRef Buffer, size_t &MatchLen,
   // If this is a fixed string pattern, just match it now.
   if (!FixedStr.empty()) {
     MatchLen = FixedStr.size();
-    size_t Pos = Buffer.find(FixedStr);
+    size_t Pos = IgnoreCase ? Buffer.find_lower(FixedStr)
+                            : Buffer.find(FixedStr);
     if (Pos == StringRef::npos)
       return make_error<FileCheckNotFoundError>();
     return Pos;
@@ -657,7 +659,10 @@ Expected<size_t> FileCheckPattern::match(StringRef Buffer, size_t &MatchLen,
   }
 
   SmallVector<StringRef, 4> MatchInfo;
-  if (!Regex(RegExToMatch, Regex::Newline).match(Buffer, &MatchInfo))
+  unsigned int Flags = Regex::Newline;
+  if (IgnoreCase)
+    Flags |= Regex::IgnoreCase;
+  if (!Regex(RegExToMatch, Flags).match(Buffer, &MatchInfo))
     return make_error<FileCheckNotFoundError>();
 
   // Successful regex match.