Fix STL caster regression for containers with proxies

pybind · Sep 1, 2017 · a7cc2cc · a7cc2cc
1 parent 61f70fc
commit a7cc2cc
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Showing 4 changed files with 20 additions and 4 deletions.
diff --git a/docs/changelog.rst b/docs/changelog.rst
@@ -11,6 +11,14 @@ v2.3.0 (Not yet released)
 
 * TBD
 
+v2.2.1 (Not yet released)
+-----------------------------------------------------
+
+* Fixed a regression where the automatic ``std::vector<bool>`` caster would
+  fail to compile. The same fix also applies to any container which returns
+  element proxies instead of references.
+  `#1053 <https://github.com/pybind/pybind11/pull/1053>`_.
+
 v2.2.0 (August 31, 2017)
 -----------------------------------------------------
 

diff --git a/include/pybind11/stl.h b/include/pybind11/stl.h
@@ -83,7 +83,7 @@ template <typename Type, typename Key> struct set_caster {
     template <typename T>
     static handle cast(T &&src, return_value_policy policy, handle parent) {
         pybind11::set s;
-        for (auto &value: src) {
+        for (auto &&value : src) {
             auto value_ = reinterpret_steal<object>(key_conv::cast(forward_like<T>(value), policy, parent));
             if (!value_ || !s.add(value_))
                 return handle();
@@ -117,7 +117,7 @@ template <typename Type, typename Key, typename Value> struct map_caster {
     template <typename T>
     static handle cast(T &&src, return_value_policy policy, handle parent) {
         dict d;
-        for (auto &kv: src) {
+        for (auto &&kv : src) {
             auto key = reinterpret_steal<object>(key_conv::cast(forward_like<T>(kv.first), policy, parent));
             auto value = reinterpret_steal<object>(value_conv::cast(forward_like<T>(kv.second), policy, parent));
             if (!key || !value)
@@ -159,7 +159,7 @@ template <typename Type, typename Value> struct list_caster {
     static handle cast(T &&src, return_value_policy policy, handle parent) {
         list l(src.size());
         size_t index = 0;
-        for (auto &value: src) {
+        for (auto &&value : src) {
             auto value_ = reinterpret_steal<object>(value_conv::cast(forward_like<T>(value), policy, parent));
             if (!value_)
                 return handle();
@@ -213,7 +213,7 @@ template <typename ArrayType, typename Value, bool Resizable, size_t Size = 0> s
     static handle cast(T &&src, return_value_policy policy, handle parent) {
         list l(src.size());
         size_t index = 0;
-        for (auto &value: src) {
+        for (auto &&value : src) {
             auto value_ = reinterpret_steal<object>(value_conv::cast(forward_like<T>(value), policy, parent));
             if (!value_)
                 return handle();

diff --git a/tests/test_stl.cpp b/tests/test_stl.cpp
@@ -48,6 +48,11 @@ TEST_SUBMODULE(stl, m) {
     // test_vector
     m.def("cast_vector", []() { return std::vector<int>{1}; });
     m.def("load_vector", [](const std::vector<int> &v) { return v.at(0) == 1 && v.at(1) == 2; });
+    // `std::vector<bool>` is special because it returns a proxy object instead of reference
+    m.def("cast_bool_vector", []() { return std::vector<bool>{true, false}; });
+    m.def("load_bool_vector", [](const std::vector<bool> &v) {
+        return v.at(0) == true && v.at(1) == false;
+    });
     // Unnumbered regression (caused by #936): pointers to stl containers aren't castable
     static std::vector<RValueCaster> lvv{2};
     m.def("cast_ptr_vector", []() { return &lvv; });

diff --git a/tests/test_stl.py b/tests/test_stl.py
@@ -12,6 +12,9 @@ def test_vector(doc):
     assert m.load_vector(l)
     assert m.load_vector(tuple(l))
 
+    assert m.cast_bool_vector() == [True, False]
+    assert m.load_bool_vector([True, False])
+
     assert doc(m.cast_vector) == "cast_vector() -> List[int]"
     assert doc(m.load_vector) == "load_vector(arg0: List[int]) -> bool"