# 6 Test Structure

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6.1 General

A test is performed by running one or more test suites. A test suite consists of test cases, configuration functions, and information functions. Test cases can be grouped in so called test case groups. A test suite is an Erlang module and test cases are implemented as Erlang functions. Test suites are stored in test directories.

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6.2 Skipping Test Cases

Certain test cases can be skipped, for example, if you know beforehand that a specific test case fails. The reason can be functionality that is not yet implemented, a bug that is known but not yet fixed, or some functionality that does not work or is not applicable on a specific platform.

Test cases can be skipped in the following ways:

- Using skip_suites and skip_cases terms in test specifications.
- Returning {skip,Reason} from function init_per_testcase/2 or init_per_suite/1.
- Returning {skip,Reason} from the execution clause of the test case. The execution clause is called, so the author must ensure that the test case does not run.

When a test case is skipped, it is noted as SKIPPED in the HTML log.

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6.3 Definition of Terms

Auto-skipped test case

  When a configuration function fails (that is, terminates unexpectedly), the test cases depending on the configuration function are skipped automatically by Common Test. The status of the test cases is then "auto-skipped". Test cases are also "auto-skipped" by Common Test if the required configuration data is unavailable at runtime.

Configuration function

  A function in a test suite that is meant to be used for setting up, cleaning up, and/or verifying the state and environment on the System Under Test (SUT) and/or the Common Test host node, so that a test case (or a set of test cases) can execute correctly.

Configuration file

  A file containing data related to a test and/or an SUT, for example, protocol server addresses, client login details, and hardware interface addresses. That is, any data that is to be handled as variable in the suite and not be hard-coded.

Configuration variable

  A name (an Erlang atom) associated with a data value read from a configuration file.

data_dir

  Data directory for a test suite. This directory contains any files used by the test suite, for example, extra Erlang modules, binaries, or data files.

Information function

  A function in a test suite that returns a list of properties (read by the Common Test server) that describes the conditions for executing the test cases in the suite.

Major log file

  An overview and summary log file for one or more test suites.

Minor log file

  A log file for one particular test case. Also called the test case log file.

priv_dir

  Private directory for a test suite. This directory is to be used when the test suite needs to write to files.

ct_run

  The name of an executable program that can be used as an interface for specifying and running tests with Common Test.

Test case

  A single test included in a test suite. A test case is implemented as a function in a test suite module.

Test case group

  A set of test cases sharing configuration functions and execution properties. The execution properties specify if the test cases in the group are to be executed in random order, in parallel, or in sequence, and if the execution of the group is be repeated. Test case groups can also be nested. That is, a group can, besides test cases, contain subgroups.

Test suite

  An Erlang module containing a collection of test cases for a specific functional area.

Test directory

  A directory containing one or more test suite modules, that is, a group of test suites.

Argument Config

  A list of key-value tuples (that is, a property list) containing runtime configuration data passed from the configuration functions to the test cases.

User-skipped test case

  The status of a test case explicitly skipped in any of the ways described in section Skipping Test Cases.