bsls_fuzztestpreconditionexception.h

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/// @file bsls_fuzztestpreconditionexception.h
///
/// The content of this file has been pre-processed for Doxygen.
///
 
 
// bsls_fuzztestpreconditionexception.h                               -*-C++-*-
#ifndef INCLUDED_BSLS_FUZZTESTPRECONDITIONEXCEPTION
#define INCLUDED_BSLS_FUZZTESTPRECONDITIONEXCEPTION
 
#include <bsls_ident.h>
BSLS_IDENT("$Id: $")
 
/// @defgroup bsls_fuzztestpreconditionexception bsls_fuzztestpreconditionexception
/// @brief  Provide an exception type for handling failed preconditions.
/// @addtogroup bsl
/// @{
/// @addtogroup bsls
/// @{
/// @addtogroup bsls_fuzztestpreconditionexception
/// @{
///
/// <h1> Outline </h1>
/// * <a href="#bsls_fuzztestpreconditionexception-purpose"> Purpose</a>
/// * <a href="#bsls_fuzztestpreconditionexception-classes"> Classes </a>
/// * <a href="#bsls_fuzztestpreconditionexception-description"> Description </a>
///   * <a href="#bsls_fuzztestpreconditionexception-usage"> Usage </a>
///
/// # Purpose {#bsls_fuzztestpreconditionexception-purpose}
/// Provide an exception type for handling failed preconditions.
///
/// # Classes {#bsls_fuzztestpreconditionexception-classes}
///
/// -  bsls::FuzzTestPreconditionException: type describing a failed precondition
///
/// @see  bsls_fuzztest
///
/// # Description {#bsls_fuzztestpreconditionexception-description}
/// This component implements an exception class,
/// `bsls::FuzzTestPreconditionException`, that provides a mechanism to convey
/// context information from a failing precondition to a test handler.  The
/// context that is captured consists of the program source of the failing
/// expression, the name of the file containing the assertion/review, the line
/// number within that file where the asserted/reviewed expression may be found,
/// and the level of the assertion/review that has failed.
///
/// ## Usage {#bsls_fuzztestpreconditionexception-usage}
///
///
/// First we write a macro to act as a precondition testing `assert` facility
/// that will throw an exception of type `bsls::FuzzTestPreconditionException`
/// if the asserted expression fails.  The thrown exception will capture the
/// source-code of the expression, the filename and line number of the failing
/// expression.
/// @code
/// #define TEST_PRECONDITION(EXPRESSION)                                    \$
///     if (!(EXPRESSION)) {                                                 \$
///         throw bsls::FuzzTestPreconditionException(#EXPRESSION, __FILE__, \$
///                                                   __LINE__, "LEVEL",     \$
///                                                   false);                \$
///     }
/// @endcode
/// Next we use the macro inside a try-block, so that we can catch the exception
/// thrown if the tested expression fails.
/// @code
///     try {
///         void *p = NULL;
///         TEST_PRECONDITION(0 != p);
///     }
/// @endcode
/// If the assertion fails, catch the exception and confirm that it correctly
/// recorded the context of where the assertion failed.
/// @code
///     catch (const bsls::FuzzTestPreconditionException& exception) {
///         assert(0     == strcmp("0 != p", exception.expression()));
///         assert(0     == strcmp(__FILE__, exception.filename()));
///         assert(9     == __LINE__ - exception.lineNumber());
///         assert(0     == strcmp("LEVEL",  exception.level()));
///         assert(false == exception.isReview());
///     }
/// @endcode
/// @}
/** @} */
/** @} */
 
/** @addtogroup bsl
 * @{
 */
/** @addtogroup bsls
 * @{
 */
/** @addtogroup bsls_fuzztestpreconditionexception
 * @{
 */
 
#include <bsls_assert.h>
#include <bsls_compilerfeatures.h>
#include <bsls_keyword.h>
#include <bsls_review.h>
 
 
 
namespace bsls {
 
                         // ===================================
                         // class FuzzTestPreconditionException
                         // ===================================
 
/// This class is an implementation detail of the `bsls` fuzz testing
/// framework and should not be used directly in user code.  It implements
/// an immutable mechanism to communicate to a test-case handler information
/// about the context of a precondition that fails.
///
/// See @ref bsls_fuzztestpreconditionexception 
class FuzzTestPreconditionException {
 
  private:
    // DATA
    const char *d_expression;  // expression that failed to assert as `true`
    const char *d_filename;    // name of file where the assert failed
    const bool  d_isReview;    // flag indicating if the failure is a review
    const char *d_level;       // level of failed assertion or review
    const int   d_lineNumber;  // line number in file where the assert failed
 
  private:
    // NOT IMPLEMENTED
    FuzzTestPreconditionException& operator=(
                    const FuzzTestPreconditionException&) BSLS_KEYWORD_DELETED;
 
  public:
    // CREATORS
 
    /// Create a `FuzzTestPreconditionException` object with the specified
    /// `expression`, `filename`, `lineNumber`, `level`, and `isReview`. 
    /// 
    /// \pre The behavior is undefined   unless `0 < line` and all of `expression`,
    /// `filename`, and `level` point to valid null-terminated character
    /// strings that will remain unmodified for the lifetime of this object
    /// (e.g., string literals).
    explicit BSLS_KEYWORD_CONSTEXPR
    FuzzTestPreconditionException(const char *expression,
                                  const char *filename,
                                  int         lineNumber,
                                  const char *level = "UNKNOWN",
                                  const bool  isReview = false);
 
#ifdef BSLS_COMPILERFEATURES_SUPPORT_DEFAULTED_FUNCTIONS
    // To avoid warnings about future incompatibility due to the deleted copy
    // assignment operator we declare the copy constructor as implicitly
    // generated.  For consistency the destructor was also placed here and
    // declared to be explicitly generated.
 
    /// Create a `FuzzTestPreconditionException` object that is a copy of
    /// the specified `original`, having the same values for the
    /// `expression`, `filename`, `lineNumber`, `level`, and `isReview` attributes.  
    /// 
    /// \note Note that   this trivial constructor's definition is
    /// compiler generated.
    FuzzTestPreconditionException(
                      const FuzzTestPreconditionException& original) = default;
 
    /// Destroy this object.  
    /// \note Note that  this trivial destructor's definition
    /// is compiler generated.
    ~FuzzTestPreconditionException() = default;
#endif
 
    // ACCESSORS
 
    /// Return a string containing the program source of the assertion that has
    /// failed.
    const char *expression() const;
 
    /// Return a string containing the filename of the source file containing
    /// the assertion that has failed.
    const char *filename() const;
 
    /// Return a string containing a representation of the level of assertion
    /// or review macro that failed.
    const char *level() const;
 
    /// Return a flag indicating if the failure is a review.
    bool isReview() const;
 
    /// Return the number of the line within the file `filename` containing the
    /// assertion that failed.
    int lineNumber() const;
};
 
// ============================================================================
//                      INLINE FUNCTION DEFINITIONS
// ============================================================================
 
                    // ===================================
                    // class FuzzTestPreconditionException
                    // ===================================
 
// CREATORS
BSLS_KEYWORD_CONSTEXPR
inline
FuzzTestPreconditionException::FuzzTestPreconditionException(
                                        const char *expression,
                                        const char *filename,
                                        const int   lineNumber,
                                        const char *level,
                                        const bool  isReview)
: d_expression(expression)
, d_filename(filename)
, d_isReview(isReview)
, d_level(level)
, d_lineNumber(lineNumber)
{
}
 
// ACCESSORS
inline
const char *FuzzTestPreconditionException::expression() const
{
    return d_expression;
}
 
inline
const char *FuzzTestPreconditionException::filename() const
{
    return d_filename;
}
 
inline
const char *FuzzTestPreconditionException::level() const
{
    return d_level;
}
 
inline
bool  FuzzTestPreconditionException::isReview() const
{
    return d_isReview;
}
 
inline
int FuzzTestPreconditionException::lineNumber() const
{
    return d_lineNumber;
}
 
}  // close package namespace
 
 
#endif
 
// ----------------------------------------------------------------------------
// Copyright 2022 Bloomberg Finance L.P.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// ----------------------------- END-OF-FILE ----------------------------------
 
/** @} */
/** @} */
/** @} */