matlab.unittest.qualifications.Assertable Class
Namespace: matlab.unittest.qualifications
Qualification to validate preconditions of a test
Description
The Assertable
class provides a qualification to validate preconditions of
a test. Apart from actions performed for failures, the Assertable
class works
the same as other qualification classes in the matlab.unittest.qualifications
namespace.
Upon an assertion failure, the Assertable
class informs the testing
framework of the failure by throwing an AssertionFailedException
object. This behavior is most useful when a failure at the
assertion point renders the remainder of the current test invalid, but does not prevent proper
execution of subsequent tests. Often, you use assertions to ensure that preconditions of the
current test are not violated or that fixtures are set up correctly. If you cannot make the
fixture teardown exception safe or
restore the environment state after failure, use fatal assertions instead.
When an assertion failure is produced within a method of the TestCase
class, the type of the method determines which tests are affected:
Test
method — The framework marks the entireTest
method as failed and incomplete.TestMethodSetup
orTestMethodTeardown
method — The framework marks theTest
method to run for that method instance as failed and incomplete.TestClassSetup
orTestClassTeardown
method — The framework marks the entire test class as failed and incomplete.
Assertions let remaining tests receive coverage when preconditions are violated in a test but the state is recoverable. They prevent unnecessary failures by not performing later verifications that fail due to invalidated preconditions. If the failure does not affect the preconditions of the test or cause problems with fixture setup or teardown, use verifications, which ensure that the full test content runs.
The matlab.unittest.qualifications.Assertable
class is a handle
class.
Methods
Public Methods
The Assertable
class provides several qualification methods for testing
values and responding to failures. For example, assertEmpty
tests that a
value is empty, and assertTrue
tests that the actual value is true.
Note
The methods of the Assertable
class correspond to the methods of the
Verifiable
class. They differ only in terms of
qualification type. You can call the Assertable
methods in the same way you
call the Verifiable
methods.
assertEqual |
Assert
that Input Arguments
Name-Value Arguments
|
assertFail |
Produce
an unconditional assertion failure. Similar to Input Arguments
|
assertFalse |
Assert
that the value of Input Arguments
|
assertNotEqual |
Assert
that Input Arguments
|
assertNotSameHandle |
Assert
that Input Arguments
|
assertReturnsTrue |
Assert
that Input Arguments
|
assertSameHandle |
Assert
that Input Arguments
|
assertThat |
Assert
that Input Arguments
|
assertTrue |
Assert
that the value of Input Arguments
|
assertError |
Assert
that Input Arguments
Output Arguments
|
assertWarning |
Assert
that Input Arguments
Output Arguments
|
assertWarningFree |
Assert
that Input Arguments
Output Arguments
|
assertGreaterThan |
Assert
that all elements of Input Arguments
|
assertGreaterThanOrEqual |
Assert
that all elements of Input Arguments
|
assertLessThan |
Assert
that all elements of Input Arguments
|
assertLessThanOrEqual |
Assert
that all elements of Input Arguments
|
assertEmpty |
Assert
that Input Arguments
|
assertLength |
Assert
that Input Arguments
|
assertNotEmpty |
Assert
that Input Arguments
|
assertNumElements |
Assert
that Input Arguments
|
assertSize |
Assert
that Input Arguments
|
assertClass |
Assert
that the class of Input Arguments
|
assertInstanceOf |
Assert
that Input Arguments
|
assertMatches |
Assert
that Input Arguments
|
assertSubstring |
Assert
that Input Arguments
|
assertEqualsBaseline (requires MATLAB
Test™) |
Assert
that Input Arguments
Name-Value Arguments
|
Events
Event Name | Trigger | Event Data | Event Attributes |
---|---|---|---|
AssertionFailed | Triggered upon failing assertion. A QualificationEventData
object is passed to listener callback functions. | matlab.unittest.qualifications.QualificationEventData |
|
AssertionPassed | Triggered upon passing assertion. A QualificationEventData
object is passed to listener callback functions. | matlab.unittest.qualifications.QualificationEventData |
|
Examples
Validate Precondition of Test
Test writing to a text file within a temporary folder. Use an assertion to fail the test and skip writing to the file if it cannot be opened.
In a file named TextFileTest.m
in your current folder, create the TextFileTest
class, which tests writing data to a text file opened within a temporary folder. If the file cannot be opened for writing, fail the test and skip the remainder of the test content by using an assertion.
classdef TextFileTest < matlab.unittest.TestCase methods (Test) function testWithTemporaryFolder(testCase) folder = testCase.createTemporaryFolder(); file = fullfile(folder,"myFile.txt"); fid = fopen(file,"w"); testCase.addTeardown(@fclose,fid) testCase.assertNotEqual(fid,-1,"IO Problem") txt = repmat("ab",1,1000); dataToWrite = join(txt); fprintf(fid,"%s",dataToWrite); testCase.verifyEqual(string(fileread(file)),dataToWrite) end end end
Run the TextFileTest
class. In this example, the assertion passes and the test runs to completion.
runtests("TextFileTest")
Running TextFileTest . Done TextFileTest __________
ans = TestResult with properties: Name: 'TextFileTest/testWithTemporaryFolder' Passed: 1 Failed: 0 Incomplete: 0 Duration: 0.0467 Details: [1×1 struct] Totals: 1 Passed, 0 Failed, 0 Incomplete. 0.046653 seconds testing time.
More About
Diagnostics
Depending on the test runner configuration, the testing framework might display
diagnostics when a qualification passes or fails. By default, the framework displays
diagnostics only when the qualification fails. You can override the default behavior by
customizing the test runner. For example, you can use a DiagnosticsOutputPlugin
instance to display both failing and passing event
diagnostics.
To add a diagnostic message to a test case, use the optional
diagnostic
argument in any of the qualification methods. You can
specify diagnostic
as a string array, character array, function handle,
or array of matlab.automation.diagnostics.Diagnostic
objects.
Exception Safe
Test content sometimes changes the state of its environment.
The content is exception safe when the environment can be restored to its
original state, even in the presence of exceptions. Exception safety ensures that a test that
throws an exception does not affect subsequent tests by corrupting the environment. To achieve
exception safety, perform all teardown actions using the addTeardown
method.
Call addTeardown
immediately before or after the original state change, without
any other code in between that can throw an exception.
For example, this code is not exception safe. If the test fails, the testing framework does not close the figure. The presence of this figure might cause subsequent tests to fail.
% Not exception safe
f = figure;
testCase.assertEqual(actual,expected)
close(f)
On the other hand, this code is exception safe, because the framework closes the figure regardless of the test outcome.
% Exception safe
f = figure;
testCase.addTeardown(@close,f)
testCase.assertEqual(actual,expected)
Tearing down a fixture using addTeardown
does not guarantee that code
is exception safe. This code is not exception safe, because the call to
addTeardown
is after the test. If the test fails, the framework does not
close the figure.
% Not exception safe
f = figure;
testCase.assertEqual(actual,expected)
testCase.addTeardown(@close,f)
Version History
Introduced in R2013aR2024b: Test if value is equal to baseline data
If you have a MATLAB
Test license, you can use the assertEqualsBaseline
method to test
if a value is equal to baseline data.
MATLAB 명령
다음 MATLAB 명령에 해당하는 링크를 클릭했습니다.
명령을 실행하려면 MATLAB 명령 창에 입력하십시오. 웹 브라우저는 MATLAB 명령을 지원하지 않습니다.
Select a Web Site
Choose a web site to get translated content where available and see local events and offers. Based on your location, we recommend that you select: .
You can also select a web site from the following list:
How to Get Best Site Performance
Select the China site (in Chinese or English) for best site performance. Other MathWorks country sites are not optimized for visits from your location.
Americas
- América Latina (Español)
- Canada (English)
- United States (English)
Europe
- Belgium (English)
- Denmark (English)
- Deutschland (Deutsch)
- España (Español)
- Finland (English)
- France (Français)
- Ireland (English)
- Italia (Italiano)
- Luxembourg (English)
- Netherlands (English)
- Norway (English)
- Österreich (Deutsch)
- Portugal (English)
- Sweden (English)
- Switzerland
- United Kingdom (English)