Fix PR#202520 - predicate called too many times in list::remove_if. Add tests for list, forward_list, and the std::remove_if algorithm

llvm-svn: 214736

libcxx/include/list

@@ -2046,6 +2046,8 @@ list<_Tp, _Alloc>::remove(const value_type& __x)
             for (; __j != __e && *__j == __x; ++__j)
                 ;
             __i = erase(__i, __j);
+            if (__i != __e)
+                __i = _VSTD::next(__i);
         }
         else
             ++__i;
@@ -2065,6 +2067,8 @@ list<_Tp, _Alloc>::remove_if(_Pred __pred)
             for (; __j != __e && __pred(*__j); ++__j)
                 ;
             __i = erase(__i, __j);
+            if (__i != __e)
+                __i = _VSTD::next(__i);
         }
         else
             ++__i;

libcxx/test/algorithms/alg.modifying.operations/alg.remove/remove_if.pass.cpp

@@ -23,6 +23,9 @@
 #endif
 
 #include "test_iterators.h"
+#include "counting_predicates.hpp"
+
+bool equal2 ( int i ) { return i == 2; }
 
 template <class Iter>
 void
@@ -30,7 +33,9 @@ test()
 {
     int ia[] = {0, 1, 2, 3, 4, 2, 3, 4, 2};
     const unsigned sa = sizeof(ia)/sizeof(ia[0]);
-    int* r = std::remove_if(ia, ia+sa, std::bind2nd(std::equal_to<int>(), 2));
+//     int* r = std::remove_if(ia, ia+sa, std::bind2nd(std::equal_to<int>(), 2));
+    unary_counting_predicate<bool(*)(int), int> cp(equal2);
+    int* r = std::remove_if(ia, ia+sa, std::ref(cp));
     assert(r == ia + sa-3);
     assert(ia[0] == 0);
     assert(ia[1] == 1);
@@ -38,6 +43,7 @@ test()
     assert(ia[3] == 4);
     assert(ia[4] == 3);
     assert(ia[5] == 4);
+    assert(cp.count() == sa);
 }
 
 #ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES

libcxx/test/containers/sequences/forwardlist/forwardlist.ops/remove_if.pass.cpp

@@ -16,6 +16,8 @@
 #include <cassert>
 
 #include "min_allocator.h"
+#include "counting_predicates.hpp"
+
 
 bool g(int i)
 {
@@ -26,98 +28,128 @@ int main()
 {
     {
         typedef int T;
+        typedef unary_counting_predicate<bool(*)(T), T> Predicate;
         typedef std::forward_list<T> C;
         const T t1[] = {0, 5, 5, 0, 0, 0, 5};
         const T t2[] = {5, 5, 5};
         C c1(std::begin(t1), std::end(t1));
         C c2(std::begin(t2), std::end(t2));
-        c1.remove_if(g);
+        Predicate cp(g);
+        c1.remove_if(std::ref(cp));
         assert(c1 == c2);
+        assert(cp.count() == std::distance(std::begin(t1), std::end(t1)));
     }
     {
         typedef int T;
+        typedef unary_counting_predicate<bool(*)(T), T> Predicate;
         typedef std::forward_list<T> C;
         const T t1[] = {0, 0, 0, 0};
         C c1(std::begin(t1), std::end(t1));
         C c2;
-        c1.remove_if(g);
+        Predicate cp(g);
+        c1.remove_if(std::ref(cp));
         assert(c1 == c2);
+        assert(cp.count() == std::distance(std::begin(t1), std::end(t1)));
     }
     {
         typedef int T;
+        typedef unary_counting_predicate<bool(*)(T), T> Predicate;
         typedef std::forward_list<T> C;
         const T t1[] = {5, 5, 5};
         const T t2[] = {5, 5, 5};
         C c1(std::begin(t1), std::end(t1));
         C c2(std::begin(t2), std::end(t2));
-        c1.remove_if(g);
+        Predicate cp(g);
+        c1.remove_if(std::ref(cp));
         assert(c1 == c2);
+        assert(cp.count() == std::distance(std::begin(t1), std::end(t1)));
     }
     {
         typedef int T;
+        typedef unary_counting_predicate<bool(*)(T), T> Predicate;
         typedef std::forward_list<T> C;
         C c1;
         C c2;
-        c1.remove_if(g);
+        Predicate cp(g);
+        c1.remove_if(std::ref(cp));
         assert(c1 == c2);
+        assert(cp.count() == 0);
     }
     {
         typedef int T;
+        typedef unary_counting_predicate<bool(*)(T), T> Predicate;
         typedef std::forward_list<T> C;
         const T t1[] = {5, 5, 5, 0};
         const T t2[] = {5, 5, 5};
         C c1(std::begin(t1), std::end(t1));
         C c2(std::begin(t2), std::end(t2));
-        c1.remove_if(g);
+        Predicate cp(g);
+        c1.remove_if(std::ref(cp));
         assert(c1 == c2);
+        assert(cp.count() == std::distance(std::begin(t1), std::end(t1)));
     }
 #if __cplusplus >= 201103L
     {
         typedef int T;
+        typedef unary_counting_predicate<bool(*)(T), T> Predicate;
         typedef std::forward_list<T, min_allocator<T>> C;
         const T t1[] = {0, 5, 5, 0, 0, 0, 5};
         const T t2[] = {5, 5, 5};
         C c1(std::begin(t1), std::end(t1));
         C c2(std::begin(t2), std::end(t2));
-        c1.remove_if(g);
+        Predicate cp(g);
+        c1.remove_if(std::ref(cp));
         assert(c1 == c2);
+        assert(cp.count() == std::distance(std::begin(t1), std::end(t1)));
     }
     {
         typedef int T;
+        typedef unary_counting_predicate<bool(*)(T), T> Predicate;
         typedef std::forward_list<T, min_allocator<T>> C;
         const T t1[] = {0, 0, 0, 0};
         C c1(std::begin(t1), std::end(t1));
         C c2;
-        c1.remove_if(g);
+        Predicate cp(g);
+        c1.remove_if(std::ref(cp));
         assert(c1 == c2);
+        assert(cp.count() == std::distance(std::begin(t1), std::end(t1)));
     }
     {
         typedef int T;
+        typedef unary_counting_predicate<bool(*)(T), T> Predicate;
         typedef std::forward_list<T, min_allocator<T>> C;
         const T t1[] = {5, 5, 5};
         const T t2[] = {5, 5, 5};
         C c1(std::begin(t1), std::end(t1));
         C c2(std::begin(t2), std::end(t2));
-        c1.remove_if(g);
+        Predicate cp(g);
+        c1.remove_if(std::ref(cp));
         assert(c1 == c2);
+        assert(cp.count() == std::distance(std::begin(t1), std::end(t1)));
     }
     {
         typedef int T;
+        typedef unary_counting_predicate<bool(*)(T), T> Predicate;
         typedef std::forward_list<T, min_allocator<T>> C;
         C c1;
         C c2;
-        c1.remove_if(g);
+        Predicate cp(g);
+        c1.remove_if(std::ref(cp));
         assert(c1 == c2);
+        assert(cp.count() == 0);
     }
     {
         typedef int T;
+        typedef unary_counting_predicate<bool(*)(T), T> Predicate;
         typedef std::forward_list<T, min_allocator<T>> C;
         const T t1[] = {5, 5, 5, 0};
         const T t2[] = {5, 5, 5};
         C c1(std::begin(t1), std::end(t1));
         C c2(std::begin(t2), std::end(t2));
-        c1.remove_if(g);
+        Predicate cp(g);
+        c1.remove_if(std::ref(cp));
         assert(c1 == c2);
+        assert(cp.count() == std::distance(std::begin(t1), std::end(t1)));
     }
 #endif
 }

libcxx/test/containers/sequences/list/list.ops/remove_if.pass.cpp

@@ -16,28 +16,49 @@
 #include <functional>
 
 #include "min_allocator.h"
+#include "counting_predicates.hpp"
+
+bool even(int i)
+{
+    return i % 2 == 0;
+}
 
 bool g(int i)
 {
     return i < 3;
 }
 
+typedef unary_counting_predicate<bool(*)(int), int> Predicate;
+
 int main()
 {
     {
     int a1[] = {1, 2, 3, 4};
     int a2[] = {3, 4};
     std::list<int> c(a1, a1+4);
-    c.remove_if(g);
+    Predicate cp(g);
+    c.remove_if(std::ref(cp));
     assert(c == std::list<int>(a2, a2+2));
+    assert(cp.count() == 4);
+    }
+    {
+    int a1[] = {1, 2, 3, 4};
+    int a2[] = {1, 3};
+    std::list<int> c(a1, a1+4);
+    Predicate cp(even);
+    c.remove_if(std::ref(cp));
+    assert(c == std::list<int>(a2, a2+2));
+    assert(cp.count() == 4);
     }
 #if __cplusplus >= 201103L
     {
     int a1[] = {1, 2, 3, 4};
     int a2[] = {3, 4};
     std::list<int, min_allocator<int>> c(a1, a1+4);
-    c.remove_if(g);
+    Predicate cp(g);
+    c.remove_if(std::ref(cp));
     assert((c == std::list<int, min_allocator<int>>(a2, a2+2)));
+    assert(cp.count() == 4);
     }
 #endif
 }

libcxx/test/support/counting_predicates.hpp

@@ -11,16 +11,13 @@
 #define __COUNTING_PREDICATES_H
 
 
-template <typename Predicate>
-struct unary_counting_predicate {
+template <typename Predicate, typename Arg>
+struct unary_counting_predicate : public std::unary_function<Arg, bool>  {
 public:
 	unary_counting_predicate(Predicate p) : p_(p), count_(0) {}
 	~unary_counting_predicate() {}
 	
-	typedef typename Predicate::argument_type argument_type;
-	typedef bool result_type;
-	
-	bool operator () (const argument_type &a) const { ++count_; return p_(a); }
+	bool operator () (const Arg &a) const { ++count_; return p_(a); }
 	size_t count() const { return count_; }
 	void reset() { count_ = 0; }