Improve clang-format's memoization behavior.

Deeply nested expressions basically break clang-format's memoization.
This patch slightly improves the situations and makes expressions like

  aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(
      aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(
          aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(
              aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(
                  aaaaa(aaaaa())))))))))))))))))))))))))))))))))))))));

work.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@180264 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/unittests/Format/FormatTest.cpp b/unittests/Format/FormatTest.cpp
index 97d4df8..055b9d1 100644
--- a/unittests/Format/FormatTest.cpp
+++ b/unittests/Format/FormatTest.cpp
@@ -1702,8 +1702,30 @@
                "    : aaaaa(aaaaaaaaaaaaaaaaaaaaaa, aaaaaaaaaaaaaaaaaaaaaa,\n"
                "            aaaaaaaaaaaaaaaaaaaaaa) {}",
                OnePerLine);
+}
+
+TEST_F(FormatTest, MemoizationTests) {
+  // This breaks if the memoization lookup does not take \c Indent and
+  // \c LastSpace into account.
+  verifyFormat(
+      "extern CFRunLoopTimerRef\n"
+      "CFRunLoopTimerCreate(CFAllocatorRef allocato, CFAbsoluteTime fireDate,\n"
+      "                     CFTimeInterval interval, CFOptionFlags flags,\n"
+      "                     CFIndex order, CFRunLoopTimerCallBack callout,\n"
+      "                     CFRunLoopTimerContext *context);");
+
+  // Deep nesting somewhat works around our memoization.
+  verifyFormat(
+      "aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(\n"
+      "    aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(\n"
+      "        aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(\n"
+      "            aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(aaaaa(\n"
+      "                aaaaa())))))))))))))))))))))))))))))))))))))));",
+      getLLVMStyleWithColumns(65));
 
   // This test takes VERY long when memoization is broken.
+  FormatStyle OnePerLine = getLLVMStyle();
+  OnePerLine.ConstructorInitializerAllOnOneLineOrOnePerLine = true;
   OnePerLine.BinPackParameters = false;
   std::string input = "Constructor()\n"
                       "    : aaaa(a,\n";