From 4deabc97a17a4bc3857ee027c35493c9f8e59ad8 Mon Sep 17 00:00:00 2001
From: Billy Robert O'Neal III <bion@microsoft.com>
Date: Thu, 25 May 2017 19:01:14 +0000
Subject: [PATCH] Add asserts that the nullptr is maintained in string erase
 operations.

llvm-svn: 303899
---
 .../strings/basic.string/string.modifiers/string_erase/iter.pass.cpp   | 1 +
 .../basic.string/string.modifiers/string_erase/iter_iter.pass.cpp      | 1 +
 .../basic.string/string.modifiers/string_erase/pop_back.pass.cpp       | 1 +
 .../basic.string/string.modifiers/string_erase/size_size.pass.cpp      | 3 +++
 4 files changed, 6 insertions(+)

diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_erase/iter.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_erase/iter.pass.cpp
index 8de5fc7..31add9df 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_erase/iter.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_erase/iter.pass.cpp
@@ -24,6 +24,7 @@ test(S s, typename S::difference_type pos, S expected)
     typename S::const_iterator p = s.begin() + pos;
     typename S::iterator i = s.erase(p);
     LIBCPP_ASSERT(s.__invariants());
+    assert(s[s.size()] == typename S::value_type());
     assert(s == expected);
     assert(i - s.begin() == pos);
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_erase/iter_iter.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_erase/iter_iter.pass.cpp
index e4fe2cd..858d375 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_erase/iter_iter.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_erase/iter_iter.pass.cpp
@@ -25,6 +25,7 @@ test(S s, typename S::difference_type pos, typename S::difference_type n, S expe
     typename S::const_iterator last = s.cbegin() + pos + n;
     typename S::iterator i = s.erase(first, last);
     LIBCPP_ASSERT(s.__invariants());
+    assert(s[s.size()] == typename S::value_type());
     assert(s == expected);
     assert(i - s.begin() == pos);
 }
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_erase/pop_back.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_erase/pop_back.pass.cpp
index 64f8e50..8424b54 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_erase/pop_back.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_erase/pop_back.pass.cpp
@@ -23,6 +23,7 @@ test(S s, S expected)
 {
     s.pop_back();
     LIBCPP_ASSERT(s.__invariants());
+    assert(s[s.size()] == typename S::value_type());
     assert(s == expected);
 }
 
diff --git a/libcxx/test/std/strings/basic.string/string.modifiers/string_erase/size_size.pass.cpp b/libcxx/test/std/strings/basic.string/string.modifiers/string_erase/size_size.pass.cpp
index eb6be20..2c900bb 100644
--- a/libcxx/test/std/strings/basic.string/string.modifiers/string_erase/size_size.pass.cpp
+++ b/libcxx/test/std/strings/basic.string/string.modifiers/string_erase/size_size.pass.cpp
@@ -29,6 +29,7 @@ test(S s, typename S::size_type pos, typename S::size_type n, S expected)
     {
         s.erase(pos, n);
         LIBCPP_ASSERT(s.__invariants());
+        assert(s[s.size()] == typename S::value_type());
         assert(s == expected);
     }
 #ifndef TEST_HAS_NO_EXCEPTIONS
@@ -58,6 +59,7 @@ test(S s, typename S::size_type pos, S expected)
     {
         s.erase(pos);
         LIBCPP_ASSERT(s.__invariants());
+        assert(s[s.size()] == typename S::value_type());
         assert(s == expected);
     }
 #ifndef TEST_HAS_NO_EXCEPTIONS
@@ -83,6 +85,7 @@ test(S s, S expected)
 {
     s.erase();
     LIBCPP_ASSERT(s.__invariants());
+    assert(s[s.size()] == typename S::value_type());
     assert(s == expected);
 }
 
-- 
2.7.4