Catch2单元测试框架

简介

Catch2是一个header-only测试框架。

使用说明

#define CATCH_CONFIG_MAIN  // 宏定义指明main()函数
#include "catch.hpp"

// 测试用例
TEST_CASE( "vectors can be sized and resized", "[vector]" )
 {
    std::vector<int> v( 5 );

    REQUIRE( v.size() == 5 );
    REQUIRE( v.capacity() >= 5 );
	// 执行每一个SECTION,都会重新开始执行
    SECTION( "resizing bigger changes size and capacity" )
    {
        v.resize( 10 );

        REQUIRE( v.size() == 10 );
        REQUIRE( v.capacity() >= 10 );
    }
    // 执行下面的SECTION时，v.size()=5
    SECTION( "resizing smaller changes size but not capacity" )
    {
        v.resize( 0 );

        REQUIRE( v.size() == 0 );
        REQUIRE( v.capacity() >= 5 );
    }
    SECTION( "reserving bigger changes capacity but not size" )
    {
        v.reserve( 10 );

        REQUIRE( v.size() == 5 );
        REQUIRE( v.capacity() >= 10 );
    }
    SECTION( "reserving smaller does not change size or capacity" )
    {
        v.reserve( 0 );

        REQUIRE( v.size() == 5 );
        REQUIRE( v.capacity() >= 5 );
    }
}

Assertion

基本断言

• REQUIRE(expression)
• CHECK(expression)
• REQUIRE_FALSE(expression)
• CHECK_FALSE(expression)
  注意：REQUIRE和CHECK最主要的区别在于REQUIRE表达式为false时中断执行，而CHECK继续执行。

  Matcher比较器

• REQUIRE_THAT(lhs, matcher expression)
• CHECK_THAT(lhs, matcher expression)
  主要内置Matchers
  — string matchers:StartsWith, EndsWith, Contains, Equals and Matches
  — vector matchers:Contains, VectorContains and Equals
  — floating point matchers:WithinULP and WithinAbs

  REQUIRE_THAT( str, EndsWith( "as a service", Catch::CaseSensitive::No ) );

浮点数比较

• epsilon:default std::numeric_limits::epsilon()*100.
• margin:default 0.0.
• scale:default 0.0.

  TEST_CASE("approx epsilon", "[single-file]")
  {
  	// 闭区间
  	// [100-100*epsilon,100+100*epsilon]
  	Approx target = Approx(100).epsilon(0.01);
  
  	CHECK(100.0 == target); // Obviously true
  	CHECK(99.0 == target); // Obviously true
  	CHECK(98.1 == target); // Obviously true
  	CHECK(101.0 == target); // Obviously true
  	CHECK(101.1 == target); // Obviously true
  }
  
  TEST_CASE("approx margin", "[single-file]")
  {
  	// 闭区间
  	// [100-margin,100+margin]
  	Approx target = Approx(100).margin(1);
  
  	CHECK(100.0 == target); // Obviously true
  	CHECK(99.0 == target); // Obviously true
  	CHECK(98.1 == target); // Obviously true
  	CHECK(101.0 == target); // Obviously true
  	CHECK(101.1 == target); // Obviously true
  }

Logging

• INFO( message expression )
• WARN( message expression )
• FAIL( message expression )
• FAIL_CHECK( message expression )
• CAPTURE( expression1, expression2, … )

  int a = 1, b = 2, c = 3;
  CAPTURE( a, b, c, a + b, c > b, a == 1);
  输出：
  // 输出
  //a: = 1
  //b : = 2
  //c : = 3
  //a + b : = 3
  //c > b : = true
  //a == 1 : = true