example/calculator_test.c - third_party/cmocka - Git at Google

 /*
  * Copyright 2008 Google Inc.
  *
  * 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.
  */
 #include <stdarg.h>
 #include <stddef.h>
 #include <setjmp.h>
 #include "cmocka.h"
 #include <stdio.h>

 #ifdef _WIN32
 /* Compatibility with the Windows standard C library. */
 #define vsnprintf _vsnprintf
 #endif /* _WIN32 */

 #define array_length(x) (sizeof(x) / sizeof((x)[0]))

 /* To simplify this code, these functions and data structures could have been
  * separated out from the application example.c into a header shared with
  * test application.  However, this example illustrates how it's possible to
  * test existing code with little modification. */

 typedef int (*BinaryOperator)(int a, int b);

 typedef struct OperatorFunction {
 	const char* operator;
 	BinaryOperator function;
 } OperatorFunction;

 extern int add(int a, int b);
 extern int subtract(int a, int b);
 extern int multiply(int a, int b);
 extern int divide(int a, int b);
 extern BinaryOperator find_operator_function_by_string(
         const size_t number_of_operator_functions,
         const OperatorFunction * const operator_functions,
         const char* const operator_string);
 extern int perform_operation(
         int number_of_arguments, char *arguments[],
         const size_t number_of_operator_functions,
         const OperatorFunction * const operator_functions,
         int * const number_of_intermediate_values,
         int ** const intermediate_values, int * const error_occurred);
 extern int example_main(int argc, char *argv[]);

 int example_test_fprintf(FILE* const file, const char *format, ...) CMOCKA_PRINTF_ATTRIBUTE(2, 3);
 int example_test_printf(const char *format, ...) CMOCKA_PRINTF_ATTRIBUTE(1, 2);

 static char temporary_buffer[256];

 /* A mock fprintf function that checks the value of strings printed to the
  * standard error stream. */
 int example_test_fprintf(FILE* const file, const char *format, ...) {
 	int return_value;
 	va_list args;
 	assert_true(file == stderr);
 	va_start(args, format);
 	return_value = vsnprintf(temporary_buffer, sizeof(temporary_buffer),
 	                         format, args);
 	check_expected(temporary_buffer);
 	va_end(args);
 	return return_value;
 }

 /* A mock printf function that checks the value of strings printed to the
  * standard output stream. */
 int example_test_printf(const char *format, ...) {
 	int return_value;
 	va_list args;
 	va_start(args, format);
 	return_value = vsnprintf(temporary_buffer, sizeof(temporary_buffer),
 	                         format, args);
 	check_expected(temporary_buffer);
 	va_end(args);
 	return return_value;
 }

 /* A mock binary operator function. */
 static int binary_operator(int a, int b) {
 	check_expected(a);
 	check_expected(b);
 	return (int)mock();
 }


 /* Ensure add() adds two integers correctly. */
 static void test_add(void **state) {
         (void) state; /* unused */

 	assert_int_equal(add(3, 3), 6);
 	assert_int_equal(add(3, -3), 0);
 }

 /* Ensure subtract() subtracts two integers correctly. */
 static void test_subtract(void **state) {
         (void) state; /* unused */

 	assert_int_equal(subtract(3, 3), 0);
 	assert_int_equal(subtract(3, -3), 6);
 }

 /* Ensure multiple() mulitplies two integers correctly. */
 static void test_multiply(void **state) {
         (void) state; /* unused */

 	assert_int_equal(multiply(3, 3), 9);
 	assert_int_equal(multiply(3, 0), 0);
 }

 /* Ensure divide() divides one integer by another correctly. */
 static void test_divide(void **state) {
         (void) state; /* unused */

 	assert_int_equal(divide(10, 2), 5);
 	assert_int_equal(divide(2, 10), 0);
 }

 /* Ensure divide() asserts when trying to divide by zero. */
 static void test_divide_by_zero(void **state) {
         (void) state; /* unused */

 	expect_assert_failure(divide(100, 0));
 }

 /* Ensure find_operator_function_by_string() asserts when a NULL pointer is
  * specified as the table to search. */
 static void test_find_operator_function_by_string_null_functions(void **state) {
         (void) state; /* unused */

 	expect_assert_failure(find_operator_function_by_string(1, NULL, "test"));
 }

 /* Ensure find_operator_function_by_string() asserts when a NULL pointer is
  * specified as the string to search for. */
 static void test_find_operator_function_by_string_null_string(void **state) {
 	const OperatorFunction operator_functions[] = {
 		{"+", binary_operator},
 	};

         (void) state; /* unused */

 	expect_assert_failure(find_operator_function_by_string(
 	    array_length(operator_functions), operator_functions, NULL));
 }

 /* Ensure find_operator_function_by_string() returns NULL when a NULL pointer
  * is specified as the table to search when the table size is 0. */
 static void test_find_operator_function_by_string_valid_null_functions(void **state) {
         (void) state; /* unused */

   assert_int_equal(find_operator_function_by_string(0, NULL, "test"), NULL);
 }

 /* Ensure find_operator_function_by_string() returns NULL when searching for
  * an operator string that isn't in the specified table. */
 static void test_find_operator_function_by_string_not_found(void **state) {
 	const OperatorFunction operator_functions[] = {
 		{"+", binary_operator},
 		{"-", binary_operator},
 		{"/", binary_operator},
 	};

         (void) state; /* unused */

 	assert_int_equal(find_operator_function_by_string(
 	        array_length(operator_functions), operator_functions, "test"),
 	        NULL);
 }

 /* Ensure find_operator_function_by_string() returns the correct function when
  * searching for an operator string that is in the specified table. */
 static void test_find_operator_function_by_string_found(void **state) {
 	const OperatorFunction operator_functions[] = {
 		{"+", (BinaryOperator)0x12345678},
 		{"-", (BinaryOperator)0xDEADBEEF},
 		{"/", (BinaryOperator)0xABADCAFE},
 	};

         (void) state; /* unused */

 	assert_int_equal(find_operator_function_by_string(
 	        array_length(operator_functions), operator_functions, "-"),
 	    0xDEADBEEF);
 }

 /* Ensure perform_operation() asserts when a NULL arguments array is specified. */
 static void test_perform_operation_null_args(void **state) {
 	const OperatorFunction operator_functions[] = {
 		{"+", binary_operator},
 	};
 	int number_of_intermediate_values;
 	int *intermediate_values;
 	int error_occurred;

         (void) state; /* unused */

 	expect_assert_failure(perform_operation(
 	    1, NULL, array_length(operator_functions), operator_functions,
 	    &number_of_intermediate_values, &intermediate_values,
 	    &error_occurred));
 }

 /* Ensure perform_operation() asserts when a NULL operator_functions array is
  * specified. */
 static void test_perform_operation_null_operator_functions(void **state) {
 	const char *args[] = {
 		"1", "+", "2", "*", "4"
 	};
 	int number_of_intermediate_values;
 	int *intermediate_values;
 	int error_occurred;

         (void) state; /* unused */

 	expect_assert_failure(perform_operation(
 	    array_length(args), (char **) args, 1, NULL, &number_of_intermediate_values,
 	    &intermediate_values, &error_occurred));
 }

 /* Ensure perform_operation() asserts when a NULL pointer is specified for
  * number_of_intermediate_values. */
 static void test_perform_operation_null_number_of_intermediate_values(void **state) {
 	const OperatorFunction operator_functions[] = {
 		{"+", binary_operator},
 	};
 	const char *args[] = {
 		"1", "+", "2", "*", "4"
 	};
 	int *intermediate_values;
 	int error_occurred;

         (void) state; /* unused */

 	expect_assert_failure(perform_operation(
 	    array_length(args), (char **) args, 1, operator_functions, NULL,
 	    &intermediate_values, &error_occurred));
 }

 /* Ensure perform_operation() asserts when a NULL pointer is specified for
  * intermediate_values. */
 static void test_perform_operation_null_intermediate_values(void **state) {
 	const OperatorFunction operator_functions[] = {
 		{"+", binary_operator},
 	};
 	const char *args[] = {
 		"1", "+", "2", "*", "4"
 	};
 	int number_of_intermediate_values;
 	int error_occurred;

         (void) state; /* unused */

 	expect_assert_failure(perform_operation(
 	    array_length(args), (char **) args, array_length(operator_functions),
 	    operator_functions, &number_of_intermediate_values, NULL,
 	    &error_occurred));
 }

 /* Ensure perform_operation() returns 0 when no arguments are specified. */
 static void test_perform_operation_no_arguments(void **state) {
 	int number_of_intermediate_values;
 	int *intermediate_values;
 	int error_occurred;

         (void) state; /* unused */

 	assert_int_equal(perform_operation(
 	    0, NULL, 0, NULL, &number_of_intermediate_values, &intermediate_values,
 	    &error_occurred), 0);
 	assert_int_equal(error_occurred, 0);
 }

 /* Ensure perform_operation() returns an error if the first argument isn't
  * an integer string. */
 static void test_perform_operation_first_arg_not_integer(void **state) {
 	const OperatorFunction operator_functions[] = {
 		{"+", binary_operator},
 	};
 	const char *args[] = {
 		"test", "+", "2", "*", "4"
 	};
 	int number_of_intermediate_values;
 	int *intermediate_values;
 	int error_occurred;

         (void) state; /* unused */

 	expect_string(example_test_fprintf, temporary_buffer,
 	              "Unable to parse integer from argument test\n");

 	assert_int_equal(perform_operation(
 	    array_length(args), (char **) args, array_length(operator_functions),
 	    operator_functions, &number_of_intermediate_values,
 	    &intermediate_values, &error_occurred), 0);
 	assert_int_equal(error_occurred, 1);
 }

 /* Ensure perform_operation() returns an error when parsing an unknown
  * operator. */
 static void test_perform_operation_unknown_operator(void **state) {
 	const OperatorFunction operator_functions[] = {
 		{"+", binary_operator},
 	};
 	const char *args[] = {
 		"1", "*", "2", "*", "4"
 	};
 	int number_of_intermediate_values;
 	int *intermediate_values;
 	int error_occurred;

         (void) state; /* unused */

 	expect_string(example_test_fprintf, temporary_buffer,
 	              "Unknown operator *, argument 1\n");

 	assert_int_equal(perform_operation(
 	    array_length(args), (char **) args, array_length(operator_functions),
 	    operator_functions, &number_of_intermediate_values,
 	    &intermediate_values, &error_occurred), 0);
 	assert_int_equal(error_occurred, 1);
 }

 /* Ensure perform_operation() returns an error when nothing follows an
  * operator. */
 static void test_perform_operation_missing_argument(void **state) {
 	const OperatorFunction operator_functions[] = {
 		{"+", binary_operator},
 	};
 	const char *args[] = {
 		"1", "+",
 	};
 	int number_of_intermediate_values;
 	int *intermediate_values;
 	int error_occurred;

         (void) state; /* unused */

 	expect_string(example_test_fprintf, temporary_buffer,
 	              "Binary operator + missing argument\n");

 	assert_int_equal(perform_operation(
 	    array_length(args), (char **) args, array_length(operator_functions),
 	    operator_functions, &number_of_intermediate_values,
 	    &intermediate_values, &error_occurred), 0);
 	assert_int_equal(error_occurred, 1);
 }

 /* Ensure perform_operation() returns an error when an integer doesn't follow
  * an operator. */
 static void test_perform_operation_no_integer_after_operator(void **state) {
 	const OperatorFunction operator_functions[] = {
 		{"+", binary_operator},
 	};
 	const char *args[] = {
 		"1", "+", "test",
 	};
 	int number_of_intermediate_values;
 	int *intermediate_values;
 	int error_occurred;

         (void) state; /* unused */

 	expect_string(example_test_fprintf, temporary_buffer,
 	              "Unable to parse integer test of argument 2\n");

 	assert_int_equal(perform_operation(
 	    array_length(args), (char **) args, array_length(operator_functions),
 	    operator_functions, &number_of_intermediate_values,
 	    &intermediate_values, &error_occurred), 0);
 	assert_int_equal(error_occurred, 1);
 }


 /* Ensure perform_operation() succeeds given valid input parameters. */
 static void test_perform_operation(void **state) {
 	const OperatorFunction operator_functions[] = {
 		{"+", binary_operator},
 		{"*", binary_operator},
 	};
 	const char *args[] = {
 		"1", "+", "3", "*", "10",
 	};
 	int number_of_intermediate_values;
 	int *intermediate_values;
 	int error_occurred;

         (void) state; /* unused */

 	/* Setup return values of mock operator functions. */
 	/* Addition. */
 	expect_value(binary_operator, a, 1);
 	expect_value(binary_operator, b, 3);
 	will_return(binary_operator, 4);

 	/* Multiplication. */
 	expect_value(binary_operator, a, 4);
 	expect_value(binary_operator, b, 10);
 	will_return(binary_operator, 40);

 	assert_int_equal(perform_operation(
 	    array_length(args), (char **) args, array_length(operator_functions),
 	    operator_functions, &number_of_intermediate_values,
 	    &intermediate_values, &error_occurred), 40);
 	assert_int_equal(error_occurred, 0);

 	assert_true(intermediate_values);
 	assert_int_equal(intermediate_values[0], 4);
 	assert_int_equal(intermediate_values[1], 40);
 	test_free(intermediate_values);
 }


 /* Ensure main() in example.c succeeds given no arguments. */
 static void test_example_main_no_args(void **state) {
 	const char *args[] = {
 		"example",
 	};

         (void) state; /* unused */

 	assert_int_equal(example_main(array_length(args), (char **) args), 0);
 }


 /* Ensure main() in example.c succeeds given valid input arguments. */
 static void test_example_main(void **state) {
 	const char *args[] = {
 		"example", "1", "+", "3", "*", "10",
 	};

         (void) state; /* unused */

 	expect_string(example_test_printf, temporary_buffer, "1\n");
 	expect_string(example_test_printf, temporary_buffer, "  + 3 = 4\n");
 	expect_string(example_test_printf, temporary_buffer, "  * 10 = 40\n");
 	expect_string(example_test_printf, temporary_buffer, "= 40\n");

 	assert_int_equal(example_main(array_length(args), (char **) args), 0);
 }


 int main(void) {
 	UnitTest tests[] = {
 		unit_test(test_add),
 		unit_test(test_subtract),
 		unit_test(test_multiply),
 		unit_test(test_divide),
 		unit_test(test_divide_by_zero),
 		unit_test(test_find_operator_function_by_string_null_functions),
 		unit_test(test_find_operator_function_by_string_null_string),
 		unit_test(test_find_operator_function_by_string_valid_null_functions),
 		unit_test(test_find_operator_function_by_string_not_found),
 		unit_test(test_find_operator_function_by_string_found),
 		unit_test(test_perform_operation_null_args),
 		unit_test(test_perform_operation_null_operator_functions),
 		unit_test(test_perform_operation_null_number_of_intermediate_values),
 		unit_test(test_perform_operation_null_intermediate_values),
 		unit_test(test_perform_operation_no_arguments),
 		unit_test(test_perform_operation_first_arg_not_integer),
 		unit_test(test_perform_operation_unknown_operator),
 		unit_test(test_perform_operation_missing_argument),
 		unit_test(test_perform_operation_no_integer_after_operator),
 		unit_test(test_perform_operation),
 		unit_test(test_example_main_no_args),
 		unit_test(test_example_main),
 	};
 	return run_tests(tests);
 }
	/*
	* Copyright 2008 Google Inc.
	*
	* 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.
	*/
	#include <stdarg.h>
	#include <stddef.h>
	#include <setjmp.h>
	#include "cmocka.h"
	#include <stdio.h>

	#ifdef _WIN32
	/* Compatibility with the Windows standard C library. */
	#define vsnprintf _vsnprintf
	#endif /* _WIN32 */

	#define array_length(x) (sizeof(x) / sizeof((x)[0]))

	/* To simplify this code, these functions and data structures could have been
	* separated out from the application example.c into a header shared with
	* test application. However, this example illustrates how it's possible to
	* test existing code with little modification. */

	typedef int (*BinaryOperator)(int a, int b);

	typedef struct OperatorFunction {
	const char* operator;
	BinaryOperator function;
	} OperatorFunction;

	extern int add(int a, int b);
	extern int subtract(int a, int b);
	extern int multiply(int a, int b);
	extern int divide(int a, int b);
	extern BinaryOperator find_operator_function_by_string(
	const size_t number_of_operator_functions,
	const OperatorFunction * const operator_functions,
	const char* const operator_string);
	extern int perform_operation(
	int number_of_arguments, char *arguments[],
	const size_t number_of_operator_functions,
	const OperatorFunction * const operator_functions,
	int * const number_of_intermediate_values,
	int ** const intermediate_values, int * const error_occurred);
	extern int example_main(int argc, char *argv[]);

	int example_test_fprintf(FILE* const file, const char *format, ...) CMOCKA_PRINTF_ATTRIBUTE(2, 3);
	int example_test_printf(const char *format, ...) CMOCKA_PRINTF_ATTRIBUTE(1, 2);

	static char temporary_buffer[256];

	/* A mock fprintf function that checks the value of strings printed to the
	* standard error stream. */
	int example_test_fprintf(FILE* const file, const char *format, ...) {
	int return_value;
	va_list args;
	assert_true(file == stderr);
	va_start(args, format);
	return_value = vsnprintf(temporary_buffer, sizeof(temporary_buffer),
	format, args);
	check_expected(temporary_buffer);
	va_end(args);
	return return_value;
	}

	/* A mock printf function that checks the value of strings printed to the
	* standard output stream. */
	int example_test_printf(const char *format, ...) {
	int return_value;
	va_list args;
	va_start(args, format);
	return_value = vsnprintf(temporary_buffer, sizeof(temporary_buffer),
	format, args);
	check_expected(temporary_buffer);
	va_end(args);
	return return_value;
	}

	/* A mock binary operator function. */
	static int binary_operator(int a, int b) {
	check_expected(a);
	check_expected(b);
	return (int)mock();
	}


	/* Ensure add() adds two integers correctly. */
	static void test_add(void **state) {
	(void) state; /* unused */

	assert_int_equal(add(3, 3), 6);
	assert_int_equal(add(3, -3), 0);
	}

	/* Ensure subtract() subtracts two integers correctly. */
	static void test_subtract(void **state) {
	(void) state; /* unused */

	assert_int_equal(subtract(3, 3), 0);
	assert_int_equal(subtract(3, -3), 6);
	}

	/* Ensure multiple() mulitplies two integers correctly. */
	static void test_multiply(void **state) {
	(void) state; /* unused */

	assert_int_equal(multiply(3, 3), 9);
	assert_int_equal(multiply(3, 0), 0);
	}

	/* Ensure divide() divides one integer by another correctly. */
	static void test_divide(void **state) {
	(void) state; /* unused */

	assert_int_equal(divide(10, 2), 5);
	assert_int_equal(divide(2, 10), 0);
	}

	/* Ensure divide() asserts when trying to divide by zero. */
	static void test_divide_by_zero(void **state) {
	(void) state; /* unused */

	expect_assert_failure(divide(100, 0));
	}

	/* Ensure find_operator_function_by_string() asserts when a NULL pointer is
	* specified as the table to search. */
	static void test_find_operator_function_by_string_null_functions(void **state) {
	(void) state; /* unused */

	expect_assert_failure(find_operator_function_by_string(1, NULL, "test"));
	}

	/* Ensure find_operator_function_by_string() asserts when a NULL pointer is
	* specified as the string to search for. */
	static void test_find_operator_function_by_string_null_string(void **state) {
	const OperatorFunction operator_functions[] = {
	{"+", binary_operator},
	};

	(void) state; /* unused */

	expect_assert_failure(find_operator_function_by_string(
	array_length(operator_functions), operator_functions, NULL));
	}

	/* Ensure find_operator_function_by_string() returns NULL when a NULL pointer
	* is specified as the table to search when the table size is 0. */
	static void test_find_operator_function_by_string_valid_null_functions(void **state) {
	(void) state; /* unused */

	assert_int_equal(find_operator_function_by_string(0, NULL, "test"), NULL);
	}

	/* Ensure find_operator_function_by_string() returns NULL when searching for
	* an operator string that isn't in the specified table. */
	static void test_find_operator_function_by_string_not_found(void **state) {
	const OperatorFunction operator_functions[] = {
	{"+", binary_operator},
	{"-", binary_operator},
	{"/", binary_operator},
	};

	(void) state; /* unused */

	assert_int_equal(find_operator_function_by_string(
	array_length(operator_functions), operator_functions, "test"),
	NULL);
	}

	/* Ensure find_operator_function_by_string() returns the correct function when
	* searching for an operator string that is in the specified table. */
	static void test_find_operator_function_by_string_found(void **state) {
	const OperatorFunction operator_functions[] = {
	{"+", (BinaryOperator)0x12345678},
	{"-", (BinaryOperator)0xDEADBEEF},
	{"/", (BinaryOperator)0xABADCAFE},
	};

	(void) state; /* unused */

	assert_int_equal(find_operator_function_by_string(
	array_length(operator_functions), operator_functions, "-"),
	0xDEADBEEF);
	}

	/* Ensure perform_operation() asserts when a NULL arguments array is specified. */
	static void test_perform_operation_null_args(void **state) {
	const OperatorFunction operator_functions[] = {
	{"+", binary_operator},
	};
	int number_of_intermediate_values;
	int *intermediate_values;
	int error_occurred;

	(void) state; /* unused */

	expect_assert_failure(perform_operation(
	1, NULL, array_length(operator_functions), operator_functions,
	&number_of_intermediate_values, &intermediate_values,
	&error_occurred));
	}

	/* Ensure perform_operation() asserts when a NULL operator_functions array is
	* specified. */
	static void test_perform_operation_null_operator_functions(void **state) {
	const char *args[] = {
	"1", "+", "2", "*", "4"
	};
	int number_of_intermediate_values;
	int *intermediate_values;
	int error_occurred;

	(void) state; /* unused */

	expect_assert_failure(perform_operation(
	array_length(args), (char **) args, 1, NULL, &number_of_intermediate_values,
	&intermediate_values, &error_occurred));
	}

	/* Ensure perform_operation() asserts when a NULL pointer is specified for
	* number_of_intermediate_values. */
	static void test_perform_operation_null_number_of_intermediate_values(void **state) {
	const OperatorFunction operator_functions[] = {
	{"+", binary_operator},
	};
	const char *args[] = {
	"1", "+", "2", "*", "4"
	};
	int *intermediate_values;
	int error_occurred;

	(void) state; /* unused */

	expect_assert_failure(perform_operation(
	array_length(args), (char **) args, 1, operator_functions, NULL,
	&intermediate_values, &error_occurred));
	}

	/* Ensure perform_operation() asserts when a NULL pointer is specified for
	* intermediate_values. */
	static void test_perform_operation_null_intermediate_values(void **state) {
	const OperatorFunction operator_functions[] = {
	{"+", binary_operator},
	};
	const char *args[] = {
	"1", "+", "2", "*", "4"
	};
	int number_of_intermediate_values;
	int error_occurred;

	(void) state; /* unused */

	expect_assert_failure(perform_operation(
	array_length(args), (char **) args, array_length(operator_functions),
	operator_functions, &number_of_intermediate_values, NULL,
	&error_occurred));
	}

	/* Ensure perform_operation() returns 0 when no arguments are specified. */
	static void test_perform_operation_no_arguments(void **state) {
	int number_of_intermediate_values;
	int *intermediate_values;
	int error_occurred;

	(void) state; /* unused */

	assert_int_equal(perform_operation(
	0, NULL, 0, NULL, &number_of_intermediate_values, &intermediate_values,
	&error_occurred), 0);
	assert_int_equal(error_occurred, 0);
	}

	/* Ensure perform_operation() returns an error if the first argument isn't
	* an integer string. */
	static void test_perform_operation_first_arg_not_integer(void **state) {
	const OperatorFunction operator_functions[] = {
	{"+", binary_operator},
	};
	const char *args[] = {
	"test", "+", "2", "*", "4"
	};
	int number_of_intermediate_values;
	int *intermediate_values;
	int error_occurred;

	(void) state; /* unused */

	expect_string(example_test_fprintf, temporary_buffer,
	"Unable to parse integer from argument test\n");

	assert_int_equal(perform_operation(
	array_length(args), (char **) args, array_length(operator_functions),
	operator_functions, &number_of_intermediate_values,
	&intermediate_values, &error_occurred), 0);
	assert_int_equal(error_occurred, 1);
	}

	/* Ensure perform_operation() returns an error when parsing an unknown
	* operator. */
	static void test_perform_operation_unknown_operator(void **state) {
	const OperatorFunction operator_functions[] = {
	{"+", binary_operator},
	};
	const char *args[] = {
	"1", "", "2", "", "4"
	};
	int number_of_intermediate_values;
	int *intermediate_values;
	int error_occurred;

	(void) state; /* unused */

	expect_string(example_test_fprintf, temporary_buffer,
	"Unknown operator *, argument 1\n");

	assert_int_equal(perform_operation(
	array_length(args), (char **) args, array_length(operator_functions),
	operator_functions, &number_of_intermediate_values,
	&intermediate_values, &error_occurred), 0);
	assert_int_equal(error_occurred, 1);
	}

	/* Ensure perform_operation() returns an error when nothing follows an
	* operator. */
	static void test_perform_operation_missing_argument(void **state) {
	const OperatorFunction operator_functions[] = {
	{"+", binary_operator},
	};
	const char *args[] = {
	"1", "+",
	};
	int number_of_intermediate_values;
	int *intermediate_values;
	int error_occurred;

	(void) state; /* unused */

	expect_string(example_test_fprintf, temporary_buffer,
	"Binary operator + missing argument\n");

	assert_int_equal(perform_operation(
	array_length(args), (char **) args, array_length(operator_functions),
	operator_functions, &number_of_intermediate_values,
	&intermediate_values, &error_occurred), 0);
	assert_int_equal(error_occurred, 1);
	}

	/* Ensure perform_operation() returns an error when an integer doesn't follow
	* an operator. */
	static void test_perform_operation_no_integer_after_operator(void **state) {
	const OperatorFunction operator_functions[] = {
	{"+", binary_operator},
	};
	const char *args[] = {
	"1", "+", "test",
	};
	int number_of_intermediate_values;
	int *intermediate_values;
	int error_occurred;

	(void) state; /* unused */

	expect_string(example_test_fprintf, temporary_buffer,
	"Unable to parse integer test of argument 2\n");

	assert_int_equal(perform_operation(
	array_length(args), (char **) args, array_length(operator_functions),
	operator_functions, &number_of_intermediate_values,
	&intermediate_values, &error_occurred), 0);
	assert_int_equal(error_occurred, 1);
	}


	/* Ensure perform_operation() succeeds given valid input parameters. */
	static void test_perform_operation(void **state) {
	const OperatorFunction operator_functions[] = {
	{"+", binary_operator},
	{"*", binary_operator},
	};
	const char *args[] = {
	"1", "+", "3", "*", "10",
	};
	int number_of_intermediate_values;
	int *intermediate_values;
	int error_occurred;

	(void) state; /* unused */

	/* Setup return values of mock operator functions. */
	/* Addition. */
	expect_value(binary_operator, a, 1);
	expect_value(binary_operator, b, 3);
	will_return(binary_operator, 4);

	/* Multiplication. */
	expect_value(binary_operator, a, 4);
	expect_value(binary_operator, b, 10);
	will_return(binary_operator, 40);

	assert_int_equal(perform_operation(
	array_length(args), (char **) args, array_length(operator_functions),
	operator_functions, &number_of_intermediate_values,
	&intermediate_values, &error_occurred), 40);
	assert_int_equal(error_occurred, 0);

	assert_true(intermediate_values);
	assert_int_equal(intermediate_values[0], 4);
	assert_int_equal(intermediate_values[1], 40);
	test_free(intermediate_values);
	}


	/* Ensure main() in example.c succeeds given no arguments. */
	static void test_example_main_no_args(void **state) {
	const char *args[] = {
	"example",
	};

	(void) state; /* unused */

	assert_int_equal(example_main(array_length(args), (char **) args), 0);
	}



	/* Ensure main() in example.c succeeds given valid input arguments. */
	static void test_example_main(void **state) {
	const char *args[] = {
	"example", "1", "+", "3", "*", "10",
	};

	(void) state; /* unused */

	expect_string(example_test_printf, temporary_buffer, "1\n");
	expect_string(example_test_printf, temporary_buffer, " + 3 = 4\n");
	expect_string(example_test_printf, temporary_buffer, " * 10 = 40\n");
	expect_string(example_test_printf, temporary_buffer, "= 40\n");

	assert_int_equal(example_main(array_length(args), (char **) args), 0);
	}


	int main(void) {
	UnitTest tests[] = {
	unit_test(test_add),
	unit_test(test_subtract),
	unit_test(test_multiply),
	unit_test(test_divide),
	unit_test(test_divide_by_zero),
	unit_test(test_find_operator_function_by_string_null_functions),
	unit_test(test_find_operator_function_by_string_null_string),
	unit_test(test_find_operator_function_by_string_valid_null_functions),
	unit_test(test_find_operator_function_by_string_not_found),
	unit_test(test_find_operator_function_by_string_found),
	unit_test(test_perform_operation_null_args),
	unit_test(test_perform_operation_null_operator_functions),
	unit_test(test_perform_operation_null_number_of_intermediate_values),
	unit_test(test_perform_operation_null_intermediate_values),
	unit_test(test_perform_operation_no_arguments),
	unit_test(test_perform_operation_first_arg_not_integer),
	unit_test(test_perform_operation_unknown_operator),
	unit_test(test_perform_operation_missing_argument),
	unit_test(test_perform_operation_no_integer_after_operator),
	unit_test(test_perform_operation),
	unit_test(test_example_main_no_args),
	unit_test(test_example_main),
	};
	return run_tests(tests);
	}