Tidy up multi_buffer:

* Improved tests
* Refactor some declaration material
* basic_multi_buffer::clear is public

and

* Fix flat_buffer::reserve
* flat_buffer::clear is public

CHANGELOG.md

@@ -16,6 +16,7 @@ Version 200
 * Fix ostream prepare calculation for low limits
 * Tidy up flat_static_buffer tests
 * Add more tests for dynamic buffers
+* Tidy up multi_buffer
 
 API Changes:
 

include/boost/beast/core/flat_buffer.hpp

@@ -83,7 +83,7 @@ class basic_flat_buffer
 
     static
     std::size_t
-    dist(char const* first, char const* last)
+    dist(char const* first, char const* last) noexcept
     {
         return static_cast<std::size_t>(last - first);
     }
@@ -370,6 +370,23 @@ public:
     void
     shrink_to_fit();
 
+    /** Deallocate the internal buffer and reduce capacity to zero.
+
+        This function deallocates the dynamically allocated
+        internal buffer, and reduces the capacity to zero without
+        affecting the maximum size. The readable and writable
+        bytes will be empty after the object is cleared.
+
+        Buffer sequences previously obtained using @ref data or
+        @ref prepare become invalid.
+
+        @par Exception Safety
+
+        No-throw guarantee.
+    */
+    void
+    clear() noexcept;
+
     /// Exchange two dynamic buffers
     template<class Alloc>
     friend
@@ -506,7 +523,6 @@ private:
     void swap(basic_flat_buffer&, std::true_type);
     void swap(basic_flat_buffer&, std::false_type);
     char* alloc(std::size_t n);
-    void clear();
 };
 
 /// A flat buffer which uses the default allocator.

include/boost/beast/core/impl/flat_buffer.hpp

@@ -254,7 +254,7 @@ reserve(std::size_t n)
 {
     if(max_ < n)
         max_ = n;
-    if(capacity() < n)
+    if(n > capacity())
         prepare(n - size());
 }
 
@@ -287,6 +287,20 @@ shrink_to_fit()
     end_ = out_;
 }
 
+template<class Allocator>
+void
+basic_flat_buffer<Allocator>::
+clear() noexcept
+{
+    alloc_traits::deallocate(
+        this->get(), begin_, size());
+    begin_ = nullptr;
+    in_ = nullptr;
+    out_ = nullptr;
+    last_ = nullptr;
+    end_ = nullptr;
+}
+
 //------------------------------------------------------------------------------
 
 template<class Allocator>
@@ -310,7 +324,11 @@ prepare(std::size_t n) ->
         // after a memmove,
         // existing capacity is sufficient
         if(len > 0)
+        {
+            BOOST_ASSERT(begin_);
+            BOOST_ASSERT(in_);
             std::memmove(begin_, in_, len);
+        }
         in_ = begin_;
         out_ = in_ + len;
         last_ = out_ + n;
@@ -375,7 +393,11 @@ copy_from(
     in_ = begin_;
     out_ = begin_ + n;
     last_ = begin_ + n;
-    std::memcpy(begin_, other.begin_, n);
+    if(begin_)
+    {
+        BOOST_ASSERT(other.begin_);
+        std::memcpy(begin_, other.begin_, n);
+    }
 }
 
 template<class Allocator>
@@ -495,20 +517,6 @@ alloc(std::size_t n)
     return alloc_traits::allocate(this->get(), n);
 }
 
-template<class Allocator>
-void
-basic_flat_buffer<Allocator>::
-clear()
-{
-    alloc_traits::deallocate(
-        this->get(), begin_, size());
-    begin_ = nullptr;
-    in_ = nullptr;
-    out_ = nullptr;
-    last_ = nullptr;
-    end_ = nullptr;
-}
-
 } // beast
 } // boost
 

include/boost/beast/core/impl/multi_buffer.hpp

@@ -148,10 +148,11 @@ class basic_multi_buffer<Allocator>::readable_bytes
     }
 
 public:
-    using value_type = typename std::conditional<
+    using value_type = typename
-        isMutable,
+        std::conditional<
-        net::mutable_buffer,
+            isMutable,
-        net::const_buffer>::type;
+            net::mutable_buffer,
+            net::const_buffer>::type;
 
     class const_iterator;
 
@@ -228,9 +229,7 @@ public:
         std::bidirectional_iterator_tag;
 
     const_iterator() = default;
-    const_iterator(const_iterator&& other) = default;
     const_iterator(const_iterator const& other) = default;
-    const_iterator& operator=(const_iterator&& other) = default;
     const_iterator& operator=(const_iterator const& other) = default;
 
     const_iterator(
@@ -314,7 +313,7 @@ class basic_multi_buffer<Allocator>::mutable_buffers_type
     }
 
 public:
-    using value_type = mutable_buffer;
+    using value_type = net::mutable_buffer;
 
     class const_iterator;
 
@@ -335,8 +334,8 @@ class basic_multi_buffer<Allocator>::mutable_buffers_type::const_iterator
     typename list_type::const_iterator it_;
 
 public:
-    using value_type =
+    using value_type = typename
-        typename mutable_buffers_type::value_type;
+        mutable_buffers_type::value_type;
     using pointer = value_type const*;
     using reference = value_type;
     using difference_type = std::ptrdiff_t;
@@ -344,9 +343,7 @@ public:
         std::bidirectional_iterator_tag;
 
     const_iterator() = default;
-    const_iterator(const_iterator&& other) = default;
     const_iterator(const_iterator const& other) = default;
-    const_iterator& operator=(const_iterator&& other) = default;
     const_iterator& operator=(const_iterator const& other) = default;
 
     const_iterator(
@@ -468,6 +465,23 @@ basic_multi_buffer<Allocator>::
     delete_list();
 }
 
+template<class Allocator>
+basic_multi_buffer<Allocator>::
+basic_multi_buffer() noexcept(default_nothrow)
+    : max_(alloc_traits::max_size(this->get()))
+    , out_(list_.end())
+{
+}
+
+template<class Allocator>
+basic_multi_buffer<Allocator>::
+basic_multi_buffer(
+    std::size_t limit) noexcept(default_nothrow)
+    : max_(limit)
+    , out_(list_.end())
+{
+}
+
 template<class Allocator>
 basic_multi_buffer<Allocator>::
 basic_multi_buffer(
@@ -672,6 +686,8 @@ void
 basic_multi_buffer<Allocator>::
 reserve(std::size_t n)
 {
+    // VFALCO The amount needs to be adjusted for
+    //        the sizeof(element) plus padding
     if(n > alloc_traits::max_size(this->get()))
         BOOST_THROW_EXCEPTION(std::length_error(
             "A basic_multi_buffer exceeded the allocator's maximum size"));
@@ -683,16 +699,17 @@ reserve(std::size_t n)
         total += out_->size() - out_pos_;
         if(n <= total)
             return;
-        auto it = out_;
+        for(auto it = out_;;)
-        while(++it != list_.end())
         {
+            if(++it == list_.end())
+                break;
             total += it->size();
             if(n <= total)
                 return;
         }
     }
     BOOST_ASSERT(n > total);
-    (void)prepare(n - total);
+    (void)prepare(n - size());
 }
 
 template<class Allocator>
@@ -717,15 +734,29 @@ shrink_to_fit() noexcept
     }
 }
 
+template<class Allocator>
+void
+basic_multi_buffer<Allocator>::
+clear() noexcept
+{
+    delete_list();
+    list_.clear();
+    out_ = list_.end();
+    in_size_ = 0;
+    in_pos_ = 0;
+    out_pos_ = 0;
+    out_end_ = 0;
+}
+
 template<class Allocator>
 auto
 basic_multi_buffer<Allocator>::
 prepare(size_type n) ->
     mutable_buffers_type
 {
-    if(in_size_ + n > max_)
+    if(in_size_ > max_ || n > (max_ - in_size_))
         BOOST_THROW_EXCEPTION(std::length_error{
-            "A basic_multi_buffer exceeded its maximum size"});
+            "basic_multi_buffer too long"});
     list_type reuse;
     std::size_t total = in_size_;
     // put all empty buffers on reuse list
@@ -943,22 +974,6 @@ copy_from(basic_multi_buffer<OtherAlloc> const& other)
         prepare(other.size()), other.data()));
 }
 
-template<class Allocator>
-void
-basic_multi_buffer<Allocator>::
-move_assign(basic_multi_buffer& other, std::false_type)
-{
-    if(this->get() != other.get())
-    {
-        copy_from(other);
-        other.clear();
-    }
-    else
-    {
-        move_assign(other, std::true_type{});
-    }
-}
-
 template<class Allocator>
 void
 basic_multi_buffer<Allocator>::
@@ -983,6 +998,22 @@ move_assign(basic_multi_buffer& other, std::true_type) noexcept
     other.out_end_ = 0;
 }
 
+template<class Allocator>
+void
+basic_multi_buffer<Allocator>::
+move_assign(basic_multi_buffer& other, std::false_type)
+{
+    if(this->get() != other.get())
+    {
+        copy_from(other);
+        other.clear();
+    }
+    else
+    {
+        move_assign(other, std::true_type{});
+    }
+}
+
 template<class Allocator>
 void
 basic_multi_buffer<Allocator>::
@@ -1093,20 +1124,6 @@ alloc(std::size_t n)
     return alloc_traits::allocate(this->get(), n);
 }
 
-template<class Allocator>
-void
-basic_multi_buffer<Allocator>::
-clear() noexcept
-{
-    delete_list();
-    list_.clear();
-    out_ = list_.end();
-    in_size_ = 0;
-    in_pos_ = 0;
-    out_pos_ = 0;
-    out_end_ = 0;
-}
-
 template<class Allocator>
 void
 basic_multi_buffer<Allocator>::

include/boost/beast/core/multi_buffer.hpp

@@ -40,7 +40,7 @@ namespace beast {
     desired size. The behavior and implementation of this
     container is most similar to `std::deque`.
 
-    Objects of this type meet the requirements of @b DynamicBuffer
+    Objects of this type meet the requirements of <em>DynamicBuffer</em>
     and have the following additional properties:
 
     @li A mutable buffer sequence representing the readable
@@ -90,8 +90,6 @@ class basic_multi_buffer
     using const_iter = typename list_type::const_iterator;
 
     using size_type = typename alloc_traits::size_type;
-    using const_buffer = net::const_buffer;
-    using mutable_buffer = net::mutable_buffer;
 
     using pocma = typename
         alloc_traits::propagate_on_container_move_assignment;
@@ -128,11 +126,7 @@ public:
         @ref max_size will return the largest value which may
         be passed to the allocator's `allocate` function.
     */
-    basic_multi_buffer() noexcept(default_nothrow)
+    basic_multi_buffer() noexcept(default_nothrow);
-        : max_(alloc_traits::max_size(this->get()))
-        , out_(list_.end())
-    {
-    }
 
     /** Constructor
 
@@ -143,11 +137,7 @@ public:
     */
     explicit
     basic_multi_buffer(
-        std::size_t limit) noexcept(default_nothrow)
+        std::size_t limit) noexcept(default_nothrow);
-        : max_(limit)
-        , out_(list_.end())
-    {
-    }
 
     /** Constructor
 
@@ -392,6 +382,23 @@ public:
     void
     shrink_to_fit() noexcept;
 
+    /** Deallocate all buffers and reduce capacity to zero.
+
+        This function deallocates all dynamically allocated
+        buffers, and reduces the capacity to zero without
+        affecting the maximum size. The readable and writable
+        bytes will be empty after the object is cleared.
+
+        Buffer sequences previously obtained using @ref data or
+        @ref prepare become invalid.
+
+        @par Exception Safety
+
+        No-throw guarantee.
+    */
+    void
+    clear() noexcept;
+
     /// Exchange two dynamic buffers
     template<class Alloc>
     friend
@@ -536,7 +543,6 @@ private:
     void swap(basic_multi_buffer&, std::false_type) noexcept;
     void delete_list() noexcept;
     char* alloc(std::size_t n);
-    void clear() noexcept;
     void debug_check() const;
 };
 

test/beast/core/buffer_test.hpp

@@ -103,88 +103,16 @@ public:
     }
 };
 
-//------------------------------------------------------------------------------
-
-namespace test {
-
-template<class DynamicBuffer>
-void
-write_buffer(DynamicBuffer& b, string_view s)
-{
-    b.commit(net::buffer_copy(
-        b.prepare(s.size()), net::buffer(
-            s.data(), s.size())));
-}
-
 template<class ConstBufferSequence>
-typename std::enable_if<
+std::size_t
-    net::is_const_buffer_sequence<ConstBufferSequence>::value,
+buffers_length(
-        std::size_t>::type
+    ConstBufferSequence const& buffers)
-buffer_count(ConstBufferSequence const& buffers)
 {
-    return std::distance(buffers.begin(), buffers.end());
+    return std::distance(
+        net::buffer_sequence_begin(buffers),
+        net::buffer_sequence_end(buffers));
 }
 
-template<class ConstBufferSequence>
-typename std::enable_if<
-    net::is_const_buffer_sequence<ConstBufferSequence>::value,
-        std::size_t>::type
-size_pre(ConstBufferSequence const& buffers)
-{
-    std::size_t n = 0;
-    for(auto it = buffers.begin(); it != buffers.end(); ++it)
-    {
-        typename ConstBufferSequence::const_iterator it0(std::move(it));
-        typename ConstBufferSequence::const_iterator it1(it0);
-        typename ConstBufferSequence::const_iterator it2;
-        it2 = it1;
-        n += net::buffer_size(*it2);
-        it = std::move(it2);
-    }
-    return n;
-}
-
-template<class ConstBufferSequence>
-typename std::enable_if<
-    net::is_const_buffer_sequence<ConstBufferSequence>::value,
-        std::size_t>::type
-size_post(ConstBufferSequence const& buffers)
-{
-    std::size_t n = 0;
-    for(auto it = buffers.begin(); it != buffers.end(); it++)
-        n += net::buffer_size(*it);
-    return n;
-}
-
-template<class ConstBufferSequence>
-typename std::enable_if<
-    net::is_const_buffer_sequence<ConstBufferSequence>::value,
-        std::size_t>::type
-size_rev_pre(ConstBufferSequence const& buffers)
-{
-    std::size_t n = 0;
-    for(auto it = buffers.end(); it != buffers.begin();)
-        n += net::buffer_size(*--it);
-    return n;
-}
-
-template<class ConstBufferSequence>
-typename std::enable_if<
-    net::is_const_buffer_sequence<ConstBufferSequence>::value,
-        std::size_t>::type
-size_rev_post(ConstBufferSequence const& buffers)
-{
-    std::size_t n = 0;
-    for(auto it = buffers.end(); it != buffers.begin();)
-    {
-        it--;
-        n += net::buffer_size(*it);
-    }
-    return n;
-}
-
-} // test
-
 //------------------------------------------------------------------------------
 
 namespace detail {

test/beast/core/buffers_cat.cpp

@@ -28,17 +28,6 @@ namespace beast {
 class buffers_cat_test : public unit_test::suite
 {
 public:
-    template<class ConstBufferSequence>
-    static
-    std::size_t
-    buffers_length(
-        ConstBufferSequence const& buffers)
-    {
-        return std::distance(
-            net::buffer_sequence_begin(buffers),
-            net::buffer_sequence_end(buffers));
-    }
-
     void
     testDefaultIterators()
     {

test/beast/core/buffers_suffix.cpp

@@ -69,7 +69,6 @@ public:
 
         // in-place init
         {
-            using namespace test;
             buffers_suffix<buffers_cat_view<
                 net::const_buffer,
                 net::const_buffer>> cb(
@@ -106,8 +105,9 @@ public:
     bool
     eq(Buffers1 const& lhs, Buffers2 const& rhs)
     {
-        using namespace test;
+        return
-        return buffers_to_string(lhs) == buffers_to_string(rhs);
+            buffers_to_string(lhs) ==
+            buffers_to_string(rhs);
     }
 
     void

test/beast/core/multi_buffer.cpp

@@ -32,20 +32,8 @@ class multi_buffer_test : public beast::unit_test::suite
 {
 public:
     BOOST_STATIC_ASSERT(
-        net::is_dynamic_buffer<
+        is_mutable_dynamic_buffer<multi_buffer>::value);
-            multi_buffer>::value);
+
-    BOOST_STATIC_ASSERT(
-        net::is_const_buffer_sequence<
-            multi_buffer::const_buffers_type>::value);
-    BOOST_STATIC_ASSERT(
-        net::is_mutable_buffer_sequence<
-            multi_buffer::mutable_data_type>::value);
-    BOOST_STATIC_ASSERT(
-        net::is_mutable_buffer_sequence<
-            multi_buffer::mutable_buffers_type>::value);
-    BOOST_STATIC_ASSERT(std::is_convertible<
-        multi_buffer::mutable_data_type,
-        multi_buffer::const_buffers_type>::value);
 #if ! BOOST_WORKAROUND(BOOST_LIBSTDCXX_VERSION, < 50000) && \
     ! BOOST_WORKAROUND(BOOST_MSVC, < 1910)
     BOOST_STATIC_ASSERT(std::is_trivially_copyable<
@@ -57,214 +45,19 @@ public:
     template<class Alloc1, class Alloc2>
     static
     bool
-    eq(basic_multi_buffer<Alloc1> const& mb1,
+    eq( basic_multi_buffer<Alloc1> const& mb1,
         basic_multi_buffer<Alloc2> const& mb2)
     {
         return buffers_to_string(mb1.data()) ==
             buffers_to_string(mb2.data());
     }
 
-    template<class ConstBufferSequence>
     void
-    expect_size(std::size_t n, ConstBufferSequence const& buffers)
+    testDynamicBuffer()
     {
-        BEAST_EXPECT(test::size_pre(buffers) == n);
+        multi_buffer b(30);
-        BEAST_EXPECT(test::size_post(buffers) == n);
+        BEAST_EXPECT(b.max_size() == 30);
-        BEAST_EXPECT(test::size_rev_pre(buffers) == n);
+        test_dynamic_buffer(*this, b);
-        BEAST_EXPECT(test::size_rev_post(buffers) == n);
-    }
-
-    template<class U, class V>
-    static
-    void
-    self_assign(U& u, V&& v)
-    {
-        u = std::forward<V>(v);
-    }
-
-    template<class DynamicBuffer>
-    void
-    testMutableData()
-    {
-        DynamicBuffer b;
-        DynamicBuffer const& cb = b;
-        ostream(b) << "Hello";
-        BOOST_STATIC_ASSERT(
-            net::is_const_buffer_sequence<
-                decltype(cb.data())>::value &&
-            ! net::is_mutable_buffer_sequence<
-                decltype(cb.data())>::value);
-        BOOST_STATIC_ASSERT(
-            net::is_const_buffer_sequence<
-                decltype(cb.cdata())>::value &&
-            ! net::is_mutable_buffer_sequence<
-                decltype(cb.cdata())>::value);
-        BOOST_STATIC_ASSERT(
-            net::is_mutable_buffer_sequence<
-                decltype(b.data())>::value);
-
-        std::for_each(
-            net::buffers_iterator<decltype(b.data())>::begin(b.data()),
-            net::buffers_iterator<decltype(b.data())>::end(b.data()),
-            [](char& c)
-            {
-                c = static_cast<char>(std::toupper(c));
-            });
-        BEAST_EXPECT(buffers_to_string(b.data()) == "HELLO");
-        BEAST_EXPECT(buffers_to_string(b.cdata()) == "HELLO");
-    }
-
-    void
-    testMatrix1()
-    {
-        using namespace test;
-        using net::buffer;
-        std::string const s = "Hello, world";
-        BEAST_EXPECT(s.size() == 12);
-        for(std::size_t i = 1; i < 12; ++i) {
-        for(std::size_t x = 1; x < 4; ++x) {
-        for(std::size_t y = 1; y < 4; ++y) {
-        std::size_t z = s.size() - (x + y);
-        {
-            multi_buffer b;
-            b.commit(buffer_copy(b.prepare(x), buffer(s.data(), x)));
-            b.commit(buffer_copy(b.prepare(y), buffer(s.data()+x, y)));
-            b.commit(buffer_copy(b.prepare(z), buffer(s.data()+x+y, z)));
-            BEAST_EXPECT(buffers_to_string(b.data()) == s);
-            {
-                multi_buffer mb2{b};
-                BEAST_EXPECT(eq(b, mb2));
-            }
-            {
-                multi_buffer mb2;
-                mb2 = b;
-                BEAST_EXPECT(eq(b, mb2));
-            }
-            {
-                multi_buffer mb2{std::move(b)};
-                BEAST_EXPECT(buffers_to_string(mb2.data()) == s);
-                expect_size(0, b.data());
-                b = std::move(mb2);
-                BEAST_EXPECT(buffers_to_string(b.data()) == s);
-                expect_size(0, mb2.data());
-            }
-            self_assign(b, b);
-            BEAST_EXPECT(buffers_to_string(b.data()) == s);
-            self_assign(b, std::move(b));
-            BEAST_EXPECT(buffers_to_string(b.data()) == s);
-        }
-        }}}
-    }
-
-    void
-    testMatrix2()
-    {
-        using namespace test;
-        using net::buffer;
-        using net::buffer_size;
-        std::string const s = "Hello, world";
-        BEAST_EXPECT(s.size() == 12);
-        for(std::size_t i = 1; i < 12; ++i) {
-        for(std::size_t x = 1; x < 4; ++x) {
-        for(std::size_t y = 1; y < 4; ++y) {
-        for(std::size_t t = 1; t < 4; ++ t) {
-        for(std::size_t u = 1; u < 4; ++ u) {
-        std::size_t z = s.size() - (x + y);
-        std::size_t v = s.size() - (t + u);
-        {
-            multi_buffer b;
-            {
-                auto d = b.prepare(z);
-                BEAST_EXPECT(buffer_size(d) == z);
-            }
-            {
-                auto d = b.prepare(0);
-                BEAST_EXPECT(buffer_size(d) == 0);
-            }
-            {
-                auto d = b.prepare(y);
-                BEAST_EXPECT(buffer_size(d) == y);
-            }
-            {
-                auto d = b.prepare(x);
-                BEAST_EXPECT(buffer_size(d) == x);
-                b.commit(buffer_copy(d, buffer(s.data(), x)));
-            }
-            BEAST_EXPECT(b.size() == x);
-            BEAST_EXPECT(buffer_size(b.data()) == b.size());
-            {
-                auto d = b.prepare(x);
-                BEAST_EXPECT(buffer_size(d) == x);
-            }
-            {
-                auto d = b.prepare(0);
-                BEAST_EXPECT(buffer_size(d) == 0);
-            }
-            {
-                auto d = b.prepare(z);
-                BEAST_EXPECT(buffer_size(d) == z);
-            }
-            {
-                auto d = b.prepare(y);
-                BEAST_EXPECT(buffer_size(d) == y);
-                b.commit(buffer_copy(d, buffer(s.data()+x, y)));
-            }
-            b.commit(1);
-            BEAST_EXPECT(b.size() == x + y);
-            BEAST_EXPECT(buffer_size(b.data()) == b.size());
-            {
-                auto d = b.prepare(x);
-                BEAST_EXPECT(buffer_size(d) == x);
-            }
-            {
-                auto d = b.prepare(y);
-                BEAST_EXPECT(buffer_size(d) == y);
-            }
-            {
-                auto d = b.prepare(0);
-                BEAST_EXPECT(buffer_size(d) == 0);
-            }
-            {
-                auto d = b.prepare(z);
-                BEAST_EXPECT(buffer_size(d) == z);
-                b.commit(buffer_copy(d, buffer(s.data()+x+y, z)));
-            }
-            b.commit(2);
-            BEAST_EXPECT(b.size() == x + y + z);
-            BEAST_EXPECT(buffer_size(b.data()) == b.size());
-            BEAST_EXPECT(buffers_to_string(b.data()) == s);
-            b.consume(t);
-            {
-                auto d = b.prepare(0);
-                BEAST_EXPECT(buffer_size(d) == 0);
-            }
-            BEAST_EXPECT(buffers_to_string(b.data()) == s.substr(t, std::string::npos));
-            b.consume(u);
-            BEAST_EXPECT(buffers_to_string(b.data()) == s.substr(t + u, std::string::npos));
-            b.consume(v);
-            BEAST_EXPECT(buffers_to_string(b.data()) == "");
-            b.consume(1);
-            {
-                auto d = b.prepare(0);
-                BEAST_EXPECT(buffer_size(d) == 0);
-            }
-        }
-        }}}}}
-    }
-
-    void
-    testIterators()
-    {
-        using net::buffer_size;
-        multi_buffer b;
-        b.prepare(1);
-        b.commit(1);
-        b.prepare(2);
-        b.commit(2);
-        expect_size(3, b.data());
-        b.prepare(1);
-        expect_size(3, b.prepare(3));
-        b.commit(2);
     }
 
     void
@@ -297,6 +90,14 @@ public:
                 BEAST_EXPECT(b.get_allocator() == a1);
                 BEAST_EXPECT(b.get_allocator() != unequal_t{});
             }
+            {
+                unequal_t a1;
+                basic_multi_buffer<unequal_t> b{500, a1};
+                BEAST_EXPECT(b.capacity() == 0);
+                BEAST_EXPECT(b.max_size() == 500);
+                BEAST_EXPECT(b.get_allocator() == a1);
+                BEAST_EXPECT(b.get_allocator() != unequal_t{});
+            }
         }
 
         // move construction
@@ -384,6 +185,18 @@ public:
                 BEAST_EXPECT(b1.capacity() == 0);
                 BEAST_EXPECT(buffers_to_string(b2.data()) == "Hello");
             }
+            {
+                using na_t = test::test_allocator<char,
+                    false, true, false, true, true>;
+                basic_multi_buffer<na_t> b1;
+                ostream(b1) << "Hello";
+                basic_multi_buffer<na_t> b2;
+                b2 = std::move(b1);
+                BEAST_EXPECT(b1.get_allocator() != b2.get_allocator());
+                BEAST_EXPECT(b1.size() == 0);
+                BEAST_EXPECT(b1.capacity() == 0);
+                BEAST_EXPECT(buffers_to_string(b2.data()) == "Hello");
+            }
             {
                 // propagate_on_container_move_assignment : true
                 using pocma_t = test::test_allocator<char,
@@ -451,6 +264,34 @@ public:
             BEAST_EXPECT(b.max_size() == 32);
         }
 
+        // allocator max_size
+        {
+            basic_multi_buffer<equal_t> b;
+            auto a = b.get_allocator();
+            BOOST_STATIC_ASSERT(
+                ! std::is_const<decltype(a)>::value);
+            a->max_size = 30;
+            try
+            {
+                b.prepare(1000);
+                fail("", __FILE__, __LINE__);
+            }
+            catch(std::length_error const&)
+            {
+                pass();
+            }
+            try
+            {
+                b.reserve(1000);
+                fail("", __FILE__, __LINE__);
+            }
+            catch(std::length_error const&)
+            {
+                pass();
+            }
+        }
+
+
         // prepare
         {
             {
@@ -527,6 +368,23 @@ public:
 
         // commit
         {
+            {
+                multi_buffer b;
+                b.prepare(16);
+                b.commit(16);
+                auto const n =
+                    b.capacity() - b.size();
+                b.prepare(n);
+                b.commit(n);
+                auto const size =
+                    b.size();
+                auto const capacity =
+                    b.capacity();
+                b.commit(1);
+                BEAST_EXPECT(b.size() == size);
+                BEAST_EXPECT(b.capacity() == capacity);
+            }
+
             multi_buffer b;
             b.prepare(1000);
             BEAST_EXPECT(b.capacity() >= 1000);
@@ -589,6 +447,21 @@ public:
             b.commit(20);
             b.reserve(50);
             BEAST_EXPECT(b.capacity() >= 50);
+            BEAST_EXPECT(b.size() > 1);
+            auto capacity = b.capacity();
+            b.reserve(b.size() - 1);
+            BEAST_EXPECT(b.capacity() == capacity);
+            b.reserve(b.capacity() + 1);
+            BEAST_EXPECT(b.capacity() > capacity);
+            capacity = b.capacity();
+            BEAST_EXPECT(buffers_length(
+                b.prepare(b.capacity() + 200)) > 1);
+            BEAST_EXPECT(b.capacity() > capacity);
+            b.reserve(b.capacity() + 2);
+            BEAST_EXPECT(b.capacity() > capacity);
+            capacity = b.capacity();
+            b.reserve(b.capacity());
+            BEAST_EXPECT(b.capacity() == capacity);
         }
 
         // shrink to fit
@@ -619,6 +492,23 @@ public:
             }
         }
 
+        // clear
+        {
+            multi_buffer b;
+            b.prepare(50);
+            BEAST_EXPECT(b.capacity() >= 50);
+            b.clear();
+            BEAST_EXPECT(b.size() == 0);
+            BEAST_EXPECT(b.capacity() == 0);
+            b.prepare(80);
+            b.commit(30);
+            BEAST_EXPECT(b.size() == 30);
+            BEAST_EXPECT(b.capacity() >= 80);
+            b.clear();
+            BEAST_EXPECT(b.size() == 0);
+            BEAST_EXPECT(b.capacity() == 0);
+        }
+
         // swap
         {
             {
@@ -683,14 +573,158 @@ public:
         }
     }
 
+    void
+    testMatrix1()
+    {
+        using net::buffer_size;
+
+        string_view s = "Hello, world";
+        BEAST_EXPECT(s.size() == 12);
+        for(std::size_t i = 1; i < 12; ++i) {
+        for(std::size_t x = 1; x < 4; ++x) {
+        for(std::size_t y = 1; y < 4; ++y) {
+        std::size_t z = s.size() - (x + y);
+        {
+            multi_buffer b;
+            b.commit(net::buffer_copy(
+                b.prepare(x), net::buffer(s.data(), x)));
+            b.commit(net::buffer_copy(
+                b.prepare(y), net::buffer(s.data()+x, y)));
+            b.commit(net::buffer_copy(
+                b.prepare(z), net::buffer(s.data()+x+y, z)));
+            BEAST_EXPECT(buffers_to_string(b.data()) == s);
+            {
+                multi_buffer mb2{b};
+                BEAST_EXPECT(eq(b, mb2));
+            }
+            {
+                multi_buffer mb2;
+                mb2 = b;
+                BEAST_EXPECT(eq(b, mb2));
+            }
+            {
+                multi_buffer mb2{std::move(b)};
+                BEAST_EXPECT(buffers_to_string(mb2.data()) == s);
+                BEAST_EXPECT(b.size() == 0);
+                BEAST_EXPECT(buffer_size(b.data()) == 0);
+                b = std::move(mb2);
+                BEAST_EXPECT(buffers_to_string(b.data()) == s);
+                BEAST_EXPECT(mb2.size() == 0);
+                BEAST_EXPECT(buffer_size(mb2.data()) == 0);
+            }
+        }
+        }}}
+    }
+
+    void
+    testMatrix2()
+    {
+        using namespace test;
+        using net::buffer;
+        using net::buffer_size;
+        std::string const s = "Hello, world";
+        BEAST_EXPECT(s.size() == 12);
+        for(std::size_t i = 1; i < 12; ++i) {
+        for(std::size_t x = 1; x < 4; ++x) {
+        for(std::size_t y = 1; y < 4; ++y) {
+        for(std::size_t t = 1; t < 4; ++ t) {
+        for(std::size_t u = 1; u < 4; ++ u) {
+        std::size_t z = s.size() - (x + y);
+        std::size_t v = s.size() - (t + u);
+        {
+            multi_buffer b;
+            {
+                auto d = b.prepare(z);
+                BEAST_EXPECT(buffer_size(d) == z);
+            }
+            {
+                auto d = b.prepare(0);
+                BEAST_EXPECT(buffer_size(d) == 0);
+            }
+            {
+                auto d = b.prepare(y);
+                BEAST_EXPECT(buffer_size(d) == y);
+            }
+            {
+                auto d = b.prepare(x);
+                BEAST_EXPECT(buffer_size(d) == x);
+                b.commit(buffer_copy(d, buffer(s.data(), x)));
+            }
+            BEAST_EXPECT(b.size() == x);
+            BEAST_EXPECT(buffer_size(b.data()) == b.size());
+            {
+                auto d = b.prepare(x);
+                BEAST_EXPECT(buffer_size(d) == x);
+            }
+            {
+                auto d = b.prepare(0);
+                BEAST_EXPECT(buffer_size(d) == 0);
+            }
+            {
+                auto d = b.prepare(z);
+                BEAST_EXPECT(buffer_size(d) == z);
+            }
+            {
+                auto d = b.prepare(y);
+                BEAST_EXPECT(buffer_size(d) == y);
+                b.commit(buffer_copy(d, buffer(s.data()+x, y)));
+            }
+            b.commit(1);
+            BEAST_EXPECT(b.size() == x + y);
+            BEAST_EXPECT(buffer_size(b.data()) == b.size());
+            {
+                auto d = b.prepare(x);
+                BEAST_EXPECT(buffer_size(d) == x);
+            }
+            {
+                auto d = b.prepare(y);
+                BEAST_EXPECT(buffer_size(d) == y);
+            }
+            {
+                auto d = b.prepare(0);
+                BEAST_EXPECT(buffer_size(d) == 0);
+            }
+            {
+                auto d = b.prepare(z);
+                BEAST_EXPECT(buffer_size(d) == z);
+                b.commit(buffer_copy(d, buffer(s.data()+x+y, z)));
+            }
+            b.commit(2);
+            BEAST_EXPECT(b.size() == x + y + z);
+            BEAST_EXPECT(buffer_size(b.data()) == b.size());
+            BEAST_EXPECT(buffers_to_string(b.data()) == s);
+            b.consume(t);
+            {
+                auto d = b.prepare(0);
+                BEAST_EXPECT(buffer_size(d) == 0);
+            }
+            BEAST_EXPECT(buffers_to_string(b.data()) ==
+                s.substr(t, std::string::npos));
+            b.consume(u);
+            BEAST_EXPECT(buffers_to_string(b.data()) ==
+                s.substr(t + u, std::string::npos));
+            b.consume(v);
+            BEAST_EXPECT(buffers_to_string(b.data()).empty());
+            b.consume(1);
+            {
+                auto d = b.prepare(0);
+                BEAST_EXPECT(buffer_size(d) == 0);
+            }
+        }
+        }}}}}
+    }
+
     void
     run() override
     {
+        testDynamicBuffer();
+        testMembers();
         testMatrix1();
         testMatrix2();
+#if 0
         testIterators();
-        testMembers();
         testMutableData<multi_buffer>();
+#endif
     }
 };
 

test/beast/core/static_buffer.cpp

@@ -87,7 +87,6 @@ public:
     void
     testStaticBuffer()
     {
-        using namespace test;
         using net::buffer;
         using net::buffer_size;
         char buf[12];
@@ -195,7 +194,6 @@ public:
     void
     testBuffer()
     {
-        using namespace test;
         string_view const s = "Hello, world!";
         
         // static_buffer_base
@@ -234,9 +232,9 @@ public:
         // cause memmove
         {
             static_buffer<10> b;
-            write_buffer(b, "12345");
+            ostream(b) << "12345";
             b.consume(3);
-            write_buffer(b, "67890123");
+            ostream(b) << "67890123";
             BEAST_EXPECT(buffers_to_string(b.data()) == "4567890123");
             try
             {