Add test for FixedStreamArrayIterator::operator->

The operator-> implementation comes from iterator_facade_base, so it should
just work given that the iterator has a tested operator*.  But r302257 showed
that required careful handling of for the const qualifier.  This patch ensures
the fix in r302257 doesn't regress.

Differential Revision: https://reviews.llvm.org/D33249

llvm-svn: 303215

llvm/unittests/Support/BinaryStreamTest.cpp

@@ -16,6 +16,7 @@
 #include "gtest/gtest.h"
 
 #include <unordered_map>
+#include <utility>
 
 using namespace llvm;
 using namespace llvm::support;
@@ -117,7 +118,7 @@ class BrokenStream : public WritableBinaryStream {
 
   // Buffer is organized like this:
   // -------------------------------------------------
-  // | N/2 | N/2+1 | ... | N-1 | 0 | 1 | ... | N-2-1 |
+  // | N/2 | N/2+1 | ... | N-1 | 0 | 1 | ... | N/2-1 |
   // -------------------------------------------------
   // So reads from the beginning actually come from the middle.
   MutableArrayRef<uint8_t> Data;
@@ -348,6 +349,30 @@ TEST_F(BinaryStreamTest, FixedStreamArray) {
   }
 }
 
+// Ensure FixedStreamArrayIterator::operator-> works.
+// Added for coverage of r302257.
+TEST_F(BinaryStreamTest, FixedStreamArrayIteratorArrow) {
+  std::vector<std::pair<uint32_t, uint32_t>> Pairs = {{867, 5309}, {555, 1212}};
+  ArrayRef<uint8_t> PairBytes(reinterpret_cast<uint8_t *>(Pairs.data()),
+    Pairs.size() * sizeof(Pairs[0]));
+
+  initializeInput(PairBytes, alignof(uint32_t));
+
+  for (auto &Stream : Streams) {
+    ASSERT_EQ(InputData.size(), Stream.Input->getLength());
+
+    const FixedStreamArray<std::pair<uint32_t, uint32_t>> Array(*Stream.Input);
+    auto Iter = Array.begin();
+    ASSERT_EQ(Pairs[0].first, Iter->first);
+    ASSERT_EQ(Pairs[0].second, Iter->second);
+    ++Iter;
+    ASSERT_EQ(Pairs[1].first, Iter->first);
+    ASSERT_EQ(Pairs[1].second, Iter->second);
+    ++Iter;
+    ASSERT_EQ(Array.end(), Iter);
+  }
+}
+
 // Test that VarStreamArray works correctly.
 TEST_F(BinaryStreamTest, VarStreamArray) {
   StringLiteral Strings("1. Test2. Longer Test3. Really Long Test4. Super "
@@ -686,7 +711,7 @@ TEST_F(BinaryStreamTest, BinaryItemStream) {
   std::vector<Foo> Foos = {{1, 1.0}, {2, 2.0}, {3, 3.0}};
   BumpPtrAllocator Allocator;
   for (const auto &F : Foos) {
-    uint8_t *Ptr = static_cast<uint8_t *>(Allocator.Allocate(sizeof(Foo), 
+    uint8_t *Ptr = static_cast<uint8_t *>(Allocator.Allocate(sizeof(Foo),
                                                              alignof(Foo)));
     MutableArrayRef<uint8_t> Buffer(Ptr, sizeof(Foo));
     MutableBinaryByteStream Stream(Buffer, llvm::support::big);