micro_os_plus::micro_test_plus::detail::throws_op< Exception_T > Struct Template Reference

Operator struct template to check if an expression throws a specific exception. More...

#include "micro-os-plus/micro-test-plus.h"

Inheritance diagram for micro_os_plus::micro_test_plus::detail::throws_op< Exception_T >:

Public Types
using	op_type = op
	Marker identifying the framework expression types.

Public Member Functions
template<class Callable_T> requires std::invocable<Callable_T&>
	throws_op (Callable_T &&func)
	Constructs an exception checking operator for the given callable.
constexpr	operator bool () const
	Conversion operator to boolean.
throw_outcome	outcome (void) const noexcept
	Retrieves what the invocation threw.
const std::string &	what (void) const noexcept
	Retrieves the what() of the std::exception thrown.

Private Attributes
throw_outcome	outcome_ { throw_outcome::none }
	Stores what the invocation threw, when the check failed.
const bool	value_ {}
	Stores the result of the callable invocation.
std::string	what_ {}
	Stores the what() of the std::exception thrown, when the check failed.

Detailed Description

template<class Exception_T = void>
struct micro_os_plus::micro_test_plus::detail::throws_op< Exception_T >

This primary template checks whether invoking the given callable throws an exception of the specified type. The check is performed at construction time, with the result cached for reporting and composition. Use this when a test must verify that an operation raises an expected exception of a particular type.

The callable is used only by the constructor, so it is a parameter of the constructor, not of the struct; all checks of the same exception type share one struct, and one formatter instantiation.

Template Parameters

Exception_T

The type of the exception to check for (defaults to void for any exception).

Definition at line 1497 of file detail.h.

Member Typedef Documentation

op_type

using micro_os_plus::micro_test_plus::detail::op::op_type = op

inherited

Detected by the extension::is_op concept, and inherited by all types derived from op.

Definition at line 128 of file extension.h.

Constructor & Destructor Documentation

throws_op()

template<class Exception_T>
requires std::invocable<Callable_T&>

template<class Callable_T>
requires std::invocable<Callable_T&>

micro_os_plus::micro_test_plus::detail::throws_op< Exception_T >::throws_op ( Callable_T && func )

explicit

Template Parameters

Callable_T

The type of the callable object to be invoked; it must be invocable without arguments, as an lvalue, so a mutable lambda is accepted.

Parameters

func	The callable object to be invoked.

Invokes func inside a try/catch block. If func throws an exception of type Exception_T, the result is true; if it throws any other exception the result is false; if no exception is thrown the result is false. The result is passed to the callable_op base class constructor, with what was thrown, if the result is false, to be written in the report: nothing, a std::exception, with its what(), or another exception.

The failed_requirement thrown to stop the test case after a failed require() in func is not an exception of func, and is rethrown.

Definition at line 1188 of file detail-inlines.h.

        : callable_op{ [&func] () -> callable_result
      {
        try
          {
            func ();
          }
        catch (const failed_requirement&)
          {
            throw;
          }
        catch (const Exception_T&)
          {
            return { true, throw_outcome::none, {} };
          }
        catch (const std::exception& e)
          {
            return { false, throw_outcome::std_exception,
                     e.what () != nullptr ? e.what () : "" };
          }
        catch (...)
          {
            return { false, throw_outcome::unknown_exception, {} };
          }
        return { false, throw_outcome::none, {} };
      }() }
    {

References micro_os_plus::micro_test_plus::detail::callable_op::callable_op(), micro_os_plus::micro_test_plus::detail::none, micro_os_plus::micro_test_plus::detail::std_exception, and micro_os_plus::micro_test_plus::detail::unknown_exception.

Referenced by micro_os_plus::micro_test_plus::detail::throws_op< void >::throws_op().

Member Function Documentation

operator bool()

micro_os_plus::micro_test_plus::detail::callable_op::operator bool ( ) const

nodiscardconstexprinherited

Parameters

None.

Returns

The result of the callable invocation.

Returns the result computed by the constructor of the derived operator; the callable is not invoked again.

Definition at line 1136 of file detail-inlines.h.

    {
      return value_;

References value_.

outcome()

throw_outcome micro_os_plus::micro_test_plus::detail::callable_op::outcome ( void ) const

inlinenodiscardnoexceptinherited

Parameters

None.

Returns

The kind of the exception thrown, throw_outcome::none if the callable completed, or if the expected exception was thrown.

Returns what was recorded when the check failed.

Definition at line 1147 of file detail-inlines.h.

    {
      return outcome_;

References outcome_.

Referenced by callable_op().

what()

const std::string & micro_os_plus::micro_test_plus::detail::callable_op::what ( void ) const

inlinenodiscardnoexceptinherited

Parameters

None.

Returns

The text, empty unless the outcome is throw_outcome::std_exception.

Returns the text recorded when a std::exception was thrown.

Definition at line 1157 of file detail-inlines.h.

    {
      return what_;

References what_.

Referenced by callable_op().

Member Data Documentation

outcome_

throw_outcome micro_os_plus::micro_test_plus::detail::callable_op::outcome_ { throw_outcome::none }

privateinherited

Copied from the callable_result by the constructor.

Definition at line 1461 of file detail.h.

Referenced by callable_op(), and outcome().

value_

const bool micro_os_plus::micro_test_plus::detail::callable_op::value_ {}

privateinherited

Computed once, by the derived operator constructor, which invokes the callable.

Definition at line 1453 of file detail.h.

Referenced by callable_op(), and operator bool().

what_

std::string micro_os_plus::micro_test_plus::detail::callable_op::what_ {}

privateinherited

Moved from the callable_result by the constructor; empty in the usual case, so nothing is allocated.

Definition at line 1471 of file detail.h.

Referenced by callable_op(), and what().

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The documentation for this struct was generated from the following files:

• detail.h
• detail-inlines.h