[libc++] Prepare string tests for constexpr

These are the last™ changes to the tests for constexpr preparation.

Reviewed By: Quuxplusone, #libc, Mordante

Spies: Mordante, EricWF, libcxx-commits

Differential Revision: https://reviews.llvm.org/D120951

libcxx/test/std/strings/basic.string/string.modifiers/robust_against_adl.pass.cpp

@@ -19,8 +19,8 @@ template<class T> struct Holder { T t; };
 template<class T>
 struct Charlike {
     char ch_;
-    Charlike(char ch) : ch_(ch) {}
-    operator char() const { return ch_; }
+    TEST_CONSTEXPR Charlike(char ch) : ch_(ch) {}
+    TEST_CONSTEXPR operator char() const { return ch_; }
 };
 
 bool test() {

libcxx/test/std/strings/basic.string/string.modifiers/string_append/T_size_size.pass.cpp

@@ -30,7 +30,7 @@ test(S s, SV sv, typename S::size_type pos, typename S::size_type n, S expected)
         assert(s == expected);
     }
 #ifndef TEST_HAS_NO_EXCEPTIONS
-    else
+    else if (!TEST_IS_CONSTANT_EVALUATED)
     {
         try
         {
@@ -56,7 +56,7 @@ test_npos(S s, SV sv, typename S::size_type pos, S expected)
         assert(s == expected);
     }
 #ifndef TEST_HAS_NO_EXCEPTIONS
-    else
+    else if (!TEST_IS_CONSTANT_EVALUATED)
     {
         try
         {

libcxx/test/std/strings/basic.string/string.modifiers/string_append/iterator.pass.cpp

@@ -172,7 +172,7 @@ bool test() {
   }
 #endif
 #ifndef TEST_HAS_NO_EXCEPTIONS
-  { // test iterator operations that throw
+  if (!TEST_IS_CONSTANT_EVALUATED) { // test iterator operations that throw
     typedef std::string S;
     typedef ThrowingIterator<char> TIter;
     typedef cpp17_input_iterator<TIter> IIter;
@@ -219,17 +219,20 @@ bool test() {
     std::string s_short = "hello";
     std::string s_long = "Lorem ipsum dolor sit amet, consectetur/";
     std::string s_othertype = "hello";
-    const unsigned char *first = reinterpret_cast<const unsigned char*>(s_othertype.data());
     std::string s_sneaky = "hello";
 
     test(s_short, s_short.data() + s_short.size(), s_short.data() + s_short.size() + 1,
          std::string("hello\0", 6));
     test(s_long, s_long.data() + s_long.size(), s_long.data() + s_long.size() + 1,
          std::string("Lorem ipsum dolor sit amet, consectetur/\0", 41));
-    test(s_othertype, first + 2, first + 5, std::string("hellollo"));
 
     s_sneaky.reserve(12);
     test(s_sneaky, s_sneaky.data(), s_sneaky.data() + 6, std::string("hellohello\0", 11));
+
+     if (!TEST_IS_CONSTANT_EVALUATED) {
+       const unsigned char *first = reinterpret_cast<const unsigned char*>(s_othertype.data());
+       test(s_othertype, first + 2, first + 5, std::string("hellollo"));
+     }
   }
 
   { // test with a move iterator that returns char&&

libcxx/test/std/strings/basic.string/string.modifiers/string_append/pointer.pass.cpp

@@ -18,7 +18,7 @@
 #include "min_allocator.h"
 
 template <class S>
-void
+TEST_CONSTEXPR_CXX20 void
 test(S s, const typename S::value_type* str, S expected)
 {
     s.append(str);

libcxx/test/std/strings/basic.string/string.modifiers/string_append/string_size_size.pass.cpp

@@ -30,7 +30,7 @@ test(S s, S str, typename S::size_type pos, typename S::size_type n, S expected)
         assert(s == expected);
     }
 #ifndef TEST_HAS_NO_EXCEPTIONS
-    else
+    else if (!TEST_IS_CONSTANT_EVALUATED)
     {
         try
         {
@@ -56,7 +56,7 @@ test_npos(S s, S str, typename S::size_type pos, S expected)
         assert(s == expected);
     }
 #ifndef TEST_HAS_NO_EXCEPTIONS
-    else
+    else if (!TEST_IS_CONSTANT_EVALUATED)
     {
         try
         {

libcxx/test/std/strings/basic.string/string.modifiers/string_assign/T_size_size.pass.cpp

@@ -19,7 +19,7 @@
 #include "min_allocator.h"
 
 template <class S, class SV>
-void
+TEST_CONSTEXPR_CXX20 void
 test(S s, SV sv, typename S::size_type pos, typename S::size_type n, S expected)
 {
     if (pos <= sv.size())
@@ -29,7 +29,7 @@ test(S s, SV sv, typename S::size_type pos, typename S::size_type n, S expected)
         assert(s == expected);
     }
 #ifndef TEST_HAS_NO_EXCEPTIONS
-    else
+    else if (!TEST_IS_CONSTANT_EVALUATED)
     {
         try
         {
@@ -45,7 +45,7 @@ test(S s, SV sv, typename S::size_type pos, typename S::size_type n, S expected)
 }
 
 template <class S, class SV>
-void
+TEST_CONSTEXPR_CXX20 void
 test_npos(S s, SV sv, typename S::size_type pos, S expected)
 {
     if (pos <= sv.size())
@@ -55,7 +55,7 @@ test_npos(S s, SV sv, typename S::size_type pos, S expected)
         assert(s == expected);
     }
 #ifndef TEST_HAS_NO_EXCEPTIONS
-    else
+    else if (!TEST_IS_CONSTANT_EVALUATED)
     {
         try
         {

libcxx/test/std/strings/basic.string/string.modifiers/string_assign/iterator.pass.cpp

@@ -19,7 +19,7 @@
 #include "min_allocator.h"
 
 template <class S, class It>
-void
+TEST_CONSTEXPR_CXX20 void
 test(S s, It first, It last, S expected)
 {
     s.assign(first, last);
@@ -172,7 +172,7 @@ bool test() {
   }
 #endif
 #ifndef TEST_HAS_NO_EXCEPTIONS
-  { // test iterator operations that throw
+  if (!TEST_IS_CONSTANT_EVALUATED) { // test iterator operations that throw
     typedef std::string S;
     typedef ThrowingIterator<char> TIter;
     typedef cpp17_input_iterator<TIter> IIter;