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Use std::visit to exhaust std::variant possibilities. #30773

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49 changes: 24 additions & 25 deletions src/_backend_agg_wrapper.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -63,31 +63,30 @@ PyRendererAgg_draw_text_image(RendererAgg *self,
double angle,
GCAgg &gc)
{
int x, y;

if (auto value = std::get_if<double>(&vx)) {
auto api = py::module_::import("matplotlib._api");
auto warn = api.attr("warn_deprecated");
warn("since"_a="3.10", "name"_a="x", "obj_type"_a="parameter as float",
"alternative"_a="int(x)");
x = static_cast<int>(*value);
} else if (auto value = std::get_if<int>(&vx)) {
x = *value;
} else {
throw std::runtime_error("Should not happen");
}

if (auto value = std::get_if<double>(&vy)) {
auto api = py::module_::import("matplotlib._api");
auto warn = api.attr("warn_deprecated");
warn("since"_a="3.10", "name"_a="y", "obj_type"_a="parameter as float",
"alternative"_a="int(y)");
y = static_cast<int>(*value);
} else if (auto value = std::get_if<int>(&vy)) {
y = *value;
} else {
throw std::runtime_error("Should not happen");
}
int x = std::visit(overloaded {
[&](double value) {
auto api = py::module_::import("matplotlib._api");
auto warn = api.attr("warn_deprecated");
warn("since"_a="3.10", "name"_a="x", "obj_type"_a="parameter as float",
"alternative"_a="int(x)");
return static_cast<int>(value);
},
[](int value) {
return value;
}
}, vx);
int y = std::visit(overloaded {
[&](double value) {
auto api = py::module_::import("matplotlib._api");
auto warn = api.attr("warn_deprecated");
warn("since"_a="3.10", "name"_a="y", "obj_type"_a="parameter as float",
"alternative"_a="int(x)");
return static_cast<int>(value);
},
[](int value) {
return value;
}
}, vy);

// TODO: This really shouldn't be mutable, but Agg's renderer buffers aren't const.
auto image = image_obj.mutable_unchecked<2>();
Expand Down
166 changes: 72 additions & 94 deletions src/ft2font_wrapper.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -4,6 +4,7 @@
#include <pybind11/stl.h>

#include "ft2font.h"
#include "mplutils.h"
#include "_enums.h"

#include <set>
Expand All @@ -18,23 +19,20 @@ using double_or_ = std::variant<double, T>;

template <typename T>
static T
_double_to_(const char *name, double_or_<T> &var)
_double_to_(const char *name, double_or_<T> var)
{
if (auto value = std::get_if<double>(&var)) {
auto api = py::module_::import("matplotlib._api");
auto warn = api.attr("warn_deprecated");
warn("since"_a="3.10", "name"_a=name, "obj_type"_a="parameter as float",
"alternative"_a="int({})"_s.format(name));
return static_cast<T>(*value);
} else if (auto value = std::get_if<T>(&var)) {
return *value;
} else {
// pybind11 will have only allowed types that match the variant, so this `else`
// can't happen. We only have this case because older macOS doesn't support
// `std::get` and using the conditional `std::get_if` means an `else` to silence
// compiler warnings about "unhandled" cases.
throw std::runtime_error("Should not happen");
}
return std::visit(overloaded {
[&](double value) {
auto api = py::module_::import("matplotlib._api");
auto warn = api.attr("warn_deprecated");
warn("since"_a="3.10", "name"_a=name, "obj_type"_a="parameter as float",
"alternative"_a="int({})"_s.format(name));
return static_cast<T>(value);
},
[](T value) {
return value;
}
}, var);
}

/**********************************************************************
Expand Down Expand Up @@ -603,22 +601,18 @@ static int
PyFT2Font_get_kerning(PyFT2Font *self, FT_UInt left, FT_UInt right,
std::variant<FT_Kerning_Mode, FT_UInt> mode_or_int)
{
FT_Kerning_Mode mode;

if (auto value = std::get_if<FT_UInt>(&mode_or_int)) {
auto api = py::module_::import("matplotlib._api");
auto warn = api.attr("warn_deprecated");
warn("since"_a="3.10", "name"_a="mode", "obj_type"_a="parameter as int",
"alternative"_a="Kerning enum values");
mode = static_cast<FT_Kerning_Mode>(*value);
} else if (auto value = std::get_if<FT_Kerning_Mode>(&mode_or_int)) {
mode = *value;
} else {
// NOTE: this can never happen as pybind11 would have checked the type in the
// Python wrapper before calling this function, but we need to keep the
// std::get_if instead of std::get for macOS 10.12 compatibility.
throw py::type_error("mode must be Kerning or int");
}
FT_Kerning_Mode mode = std::visit(overloaded {
[&](FT_UInt value) {
auto api = py::module_::import("matplotlib._api");
auto warn = api.attr("warn_deprecated");
warn("since"_a="3.10", "name"_a="mode", "obj_type"_a="parameter as int",
"alternative"_a="Kerning enum values");
return static_cast<FT_Kerning_Mode>(value);
},
[](FT_Kerning_Mode value) {
return value;
}
}, mode_or_int);

return self->get_kerning(left, right, mode);
}
Expand Down Expand Up @@ -708,36 +702,28 @@ PyFT2Font_set_text(PyFT2Font *self, std::u32string_view text, double angle = 0.0
std::variant<FT2Font::LanguageType, std::string> languages_or_str = nullptr)
{
std::vector<double> xys;
LoadFlags flags;

if (auto value = std::get_if<FT_Int32>(&flags_or_int)) {
auto api = py::module_::import("matplotlib._api");
auto warn = api.attr("warn_deprecated");
warn("since"_a="3.10", "name"_a="flags", "obj_type"_a="parameter as int",
"alternative"_a="LoadFlags enum values");
flags = static_cast<LoadFlags>(*value);
} else if (auto value = std::get_if<LoadFlags>(&flags_or_int)) {
flags = *value;
} else {
// NOTE: this can never happen as pybind11 would have checked the type in the
// Python wrapper before calling this function, but we need to keep the
// std::get_if instead of std::get for macOS 10.12 compatibility.
throw py::type_error("flags must be LoadFlags or int");
}

FT2Font::LanguageType languages;
if (auto value = std::get_if<FT2Font::LanguageType>(&languages_or_str)) {
languages = std::move(*value);
} else if (auto value = std::get_if<std::string>(&languages_or_str)) {
languages = std::vector<FT2Font::LanguageRange>{
FT2Font::LanguageRange{*value, 0, text.size()}
};
} else {
// NOTE: this can never happen as pybind11 would have checked the type in the
// Python wrapper before calling this function, but we need to keep the
// std::get_if instead of std::get for macOS 10.12 compatibility.
throw py::type_error("languages must be str or list of tuple");
}
LoadFlags flags = std::visit(overloaded {
[&](FT_Int32 value) {
auto api = py::module_::import("matplotlib._api");
auto warn = api.attr("warn_deprecated");
warn("since"_a="3.10", "name"_a="flags", "obj_type"_a="parameter as int",
"alternative"_a="LoadFlags enum values");
return static_cast<LoadFlags>(value);
},
[](LoadFlags value) {
return value;
}
}, flags_or_int);

FT2Font::LanguageType languages = std::visit(overloaded {
[](FT2Font::LanguageType languages) {
return languages;
},
[&](std::string value) {
return FT2Font::LanguageType{{
FT2Font::LanguageRange{value, 0, text.size()}}};
}
}, languages_or_str);

self->set_text(text, angle, static_cast<FT_Int32>(flags), features, languages, xys);

Expand Down Expand Up @@ -783,22 +769,18 @@ PyFT2Font_load_char(PyFT2Font *self, long charcode,
{
bool fallback = true;
FT2Font *ft_object = nullptr;
LoadFlags flags;

if (auto value = std::get_if<FT_Int32>(&flags_or_int)) {
auto api = py::module_::import("matplotlib._api");
auto warn = api.attr("warn_deprecated");
warn("since"_a="3.10", "name"_a="flags", "obj_type"_a="parameter as int",
"alternative"_a="LoadFlags enum values");
flags = static_cast<LoadFlags>(*value);
} else if (auto value = std::get_if<LoadFlags>(&flags_or_int)) {
flags = *value;
} else {
// NOTE: this can never happen as pybind11 would have checked the type in the
// Python wrapper before calling this function, but we need to keep the
// std::get_if instead of std::get for macOS 10.12 compatibility.
throw py::type_error("flags must be LoadFlags or int");
}
LoadFlags flags = std::visit(overloaded {
[&](FT_Int32 value) {
auto api = py::module_::import("matplotlib._api");
auto warn = api.attr("warn_deprecated");
warn("since"_a="3.10", "name"_a="flags", "obj_type"_a="parameter as int",
"alternative"_a="LoadFlags enum values");
return static_cast<LoadFlags>(value);
},
[](LoadFlags value) {
return value;
}
}, flags_or_int);

self->load_char(charcode, static_cast<FT_Int32>(flags), ft_object, fallback);

Expand Down Expand Up @@ -835,22 +817,18 @@ static PyGlyph *
PyFT2Font_load_glyph(PyFT2Font *self, FT_UInt glyph_index,
std::variant<LoadFlags, FT_Int32> flags_or_int = LoadFlags::FORCE_AUTOHINT)
{
LoadFlags flags;

if (auto value = std::get_if<FT_Int32>(&flags_or_int)) {
auto api = py::module_::import("matplotlib._api");
auto warn = api.attr("warn_deprecated");
warn("since"_a="3.10", "name"_a="flags", "obj_type"_a="parameter as int",
"alternative"_a="LoadFlags enum values");
flags = static_cast<LoadFlags>(*value);
} else if (auto value = std::get_if<LoadFlags>(&flags_or_int)) {
flags = *value;
} else {
// NOTE: this can never happen as pybind11 would have checked the type in the
// Python wrapper before calling this function, but we need to keep the
// std::get_if instead of std::get for macOS 10.12 compatibility.
throw py::type_error("flags must be LoadFlags or int");
}
LoadFlags flags = std::visit(overloaded {
[&](FT_Int32 value) {
auto api = py::module_::import("matplotlib._api");
auto warn = api.attr("warn_deprecated");
warn("since"_a="3.10", "name"_a="flags", "obj_type"_a="parameter as int",
"alternative"_a="LoadFlags enum values");
return static_cast<LoadFlags>(value);
},
[](LoadFlags value) {
return value;
}
}, flags_or_int);

self->load_glyph(glyph_index, static_cast<FT_Int32>(flags));

Expand Down
15 changes: 9 additions & 6 deletions src/mplutils.h
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Original file line number Diff line number Diff line change
Expand Up @@ -49,14 +49,18 @@ enum {
};

#ifdef __cplusplus // not for macosx.m
// Check that array has shape (N, d1) or (N, d1, d2). We cast d1, d2 to longs
// so that we don't need to access the NPY_INTP_FMT macro here.
#include <pybind11/pybind11.h>
#include <pybind11/numpy.h>

namespace py = pybind11;
using namespace pybind11::literals;

// Helper for std::visit.
template<typename... Ts> struct overloaded : Ts... { using Ts::operator()...; };
template<typename... Ts> overloaded(Ts...) -> overloaded<Ts...>;

// Check that array has shape (N, d1) or (N, d1, d2). We cast d1, d2 to longs
// so that we don't need to access the NPY_INTP_FMT macro here.
template<typename T>
inline void check_trailing_shape(T array, char const* name, long d1)
{
Expand Down Expand Up @@ -95,11 +99,10 @@ inline void check_trailing_shape(T array, char const* name, long d1, long d2)
}
}

/* In most cases, code should use safe_first_shape(obj) instead of obj.shape(0), since
safe_first_shape(obj) == 0 when any dimension is 0. */
// In most cases, code should use safe_first_shape(obj) instead of
// obj.shape(0), since safe_first_shape(obj) == 0 when any dimension is 0.
template <typename T, py::ssize_t ND>
py::ssize_t
safe_first_shape(const py::detail::unchecked_reference<T, ND> &a)
py::ssize_t safe_first_shape(const py::detail::unchecked_reference<T, ND> &a)
{
bool empty = (ND == 0);
for (py::ssize_t i = 0; i < ND; i++) {
Expand Down
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