[clang-format] Preserve spaces before a percent in (text) protos

This makes sure that we do not change the meaning of pieces of text with
format specifiers.

llvm-svn: 329263

1 files changed, 4 insertions, 0 deletions

diff --git a/clang/lib/Format/TokenAnnotator.cpp b/clang/lib/Format/TokenAnnotator.cpp
index cdf921c3c65..c2d6875e0c3 100644
--- a/clang/lib/Format/TokenAnnotator.cpp
+++ b/clang/lib/Format/TokenAnnotator.cpp
@@ -2518,6 +2518,10 @@ bool TokenAnnotator::spaceRequiredBefore(const AnnotatedLine &Line,
     // A percent is probably part of a formatting specification, such as %lld.
     if (Left.is(tok::percent))
       return false;
+    // Preserve the existence of a space before a percent for cases like 0x%04x
+    // and "%d %d"
+    if (Left.is(tok::numeric_constant) && Right.is(tok::percent))
+      return Right.WhitespaceRange.getEnd() != Right.WhitespaceRange.getBegin();
   } else if (Style.Language == FormatStyle::LK_JavaScript) {
     if (Left.is(TT_JsFatArrow))
       return true;