Important built-in assert functions

Each test needs to assert some expected behavior. The use of the XCTAssert functions tells Xcode what is expected.

A test method without a XCTAssert function will always pass as long as it compiles.

The most important assert functions are:

  • XCTAssertTrue(_:_:file:line:): This asserts that an expression is true
  • XCTAssertFalse(_:_:file:line:): This asserts that an expression is false
  • XCTAssertEqual(_:_:_:file:line:): This asserts that two expressions are equal
  • XCTAssertEqualWithAccuracy(_:_:accuracy:_:file:line:): This asserts that two expressions are the same, taking into account the accuracy defined in the accuracy parameter
  • XCTAssertNotEqual(_:_:_:file:line:): This asserts that two expressions are not ...

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