Provided by: erlang-manpages_22.2.7+dfsg-1ubuntu0.2_all 
NAME
common_test - A framework for automated testing of any target nodes.
DESCRIPTION
The Common Test framework is an environment for implementing and performing automatic and semi-automatic
execution of test cases.
In brief, Common Test supports:
* Automated execution of test suites (sets of test cases)
* Logging of events during execution
* HTML presentation of test suite results
* HTML presentation of test suite code
* Support functions for test suite authors
* Step-by-step execution of test cases
The following section describes the mandatory and optional test suite functions that Common Test calls
during test execution. For more details, see section Writing Test Suites in the User's Guide.
TEST CASE CALLBACK FUNCTIONS
The following functions define the callback interface for a test suite.
EXPORTS
Module:all() -> Tests | {skip,Reason}
Types:
Tests = [TestCase | {testcase,TestCase,TCRepeatProps} | {group,GroupName} |
{group,GroupName,Properties} | {group,GroupName,Properties,SubGroups}]
TestCase = atom()
TCRepeatProps = [{repeat,N} | {repeat_until_ok,N} | {repeat_until_fail,N}]
GroupName = atom()
Properties = [parallel | sequence | Shuffle | {GroupRepeatType,N}] | default
SubGroups = [{GroupName,Properties} | {GroupName,Properties,SubGroups}]
Shuffle = shuffle | {shuffle,Seed}
Seed = {integer(),integer(),integer()}
GroupRepeatType = repeat | repeat_until_all_ok | repeat_until_all_fail | repeat_until_any_ok |
repeat_until_any_fail
N = integer() | forever
Reason = term()
MANDATORY
Returns the list of all test cases and test case groups in the test suite module to be executed.
This list also specifies the order the cases and groups are executed by Common Test. A test case
is represented by an atom, the name of the test case function, or a testcase tuple indicating that
the test case shall be repeated. A test case group is represented by a group tuple, where
GroupName, an atom, is the name of the group (defined in groups/0). Execution properties for
groups can also be specified, both for a top-level group and for any of its subgroups. Group
execution properties specified here override properties in the group definition (see groups/0).
(With value default, the group definition properties are used).
If {skip,Reason} is returned, all test cases in the module are skipped and Reason is printed on
the HTML result page.
For details on groups, see section Test Case Groups in the User's Guide.
Module:groups() -> GroupDefs
Types:
GroupDefs = [Group]
Group = {GroupName,Properties,GroupsAndTestCases}
GroupName = atom()
Properties = [parallel | sequence | Shuffle | {GroupRepeatType,N}]
GroupsAndTestCases = [Group | {group,GroupName} | TestCase | {testcase,TestCase,TCRepeatProps}]
TestCase = atom()
TCRepeatProps = [{repeat,N} | {repeat_until_ok,N} | {repeat_until_fail,N}]
Shuffle = shuffle | {shuffle,Seed}
Seed = {integer(),integer(),integer()}
GroupRepeatType = repeat | repeat_until_all_ok | repeat_until_all_fail | repeat_until_any_ok |
repeat_until_any_fail
N = integer() | forever
OPTIONAL
Defines test case groups. For details, see section Test Case Groups in the User's Guide.
Module:suite() -> [Info]
Types:
Info = {timetrap,Time} | {require,Required} | {require,Name,Required} | {userdata,UserData} |
{silent_connections,Conns} | {stylesheet,CSSFile} | {ct_hooks, CTHs}
Time = TimeVal | TimeFunc
TimeVal = MilliSec | {seconds,integer()} | {minutes,integer()} | {hours,integer()}
TimeFunc = {Mod,Func,Args} | Fun
MilliSec = integer()
Mod = atom()
Func = atom()
Args = list()
Fun = fun()
Required = Key | {Key,SubKeys} | {Key,SubKey} | {Key,SubKey,SubKeys}
Key = atom()
SubKeys = SubKey | [SubKey]
SubKey = atom()
Name = atom()
UserData = term()
Conns = [atom()]
CSSFile = string()
CTHs = [CTHModule |
{CTHModule, CTHInitArgs} |
{CTHModule, CTHInitArgs, CTHPriority}]
CTHModule = atom()
CTHInitArgs = term()
OPTIONAL
The test suite information function. Returns a list of tagged tuples specifying various properties
related to the execution of this test suite (common for all test cases in the suite).
Tag timetrap sets the maximum time that each test case is allowed to execute (including
init_per_testcase/2 and end_per_testcase/2). If the timetrap time is exceeded, the test case fails
with reason timetrap_timeout. A TimeFunc function can be used to set a new timetrap by returning a
TimeVal. It can also be used to trigger a timetrap time-out by, at some point, returning a value
other than a TimeVal. For details, see section Timetrap Time-Outs in the User's Guide.
Tag require specifies configuration variables required by test cases (or configuration functions)
in the suite. If the required configuration variables are not found in any of the configuration
files, all test cases are skipped. For details about the require functionality, see funtion
ct:require/1,2.
With userdata, the user can specify any test suite-related information, which can be read by
calling ct:userdata/2.
Tag ct_hooks specifies the Common Test Hooks to be run with this suite.
Other tuples than the ones defined are ignored.
For details about the test suite information function, see section Test Suite Information Function
in the User's Guide.
Module:init_per_suite(Config) -> NewConfig | {skip,Reason} | {skip_and_save,Reason,SaveConfig}
Types:
Config = NewConfig = SaveConfig = [{Key,Value}]
Key = atom()
Value = term()
Reason = term()
OPTIONAL; if this function is defined, then end_per_suite/1 must also be defined.
This configuration function is called as the first function in the suite. It typically contains
initializations that are common for all test cases in the suite, and that must only be done once.
Parameter Config is the configuration data that can be modified. Whatever is returned from this
function is specified as Config to all configuration functions and test cases in the suite.
If {skip,Reason} is returned, all test cases in the suite are skipped and Reason is printed in the
overview log for the suite.
For information on save_config and skip_and_save, see section Saving Configuration Data in the
User's Guide.
Module:end_per_suite(Config) -> term() | {save_config,SaveConfig}
Types:
Config = SaveConfig = [{Key,Value}]
Key = atom()
Value = term()
OPTIONAL; if this function is defined, then init_per_suite/1 must also be defined.
This function is called as the last test case in the suite. It is meant to be used for cleaning up
after init_per_suite/1.
For information on save_config, see section Saving Configuration Data in the User's Guide.
Module:group(GroupName) -> [Info]
Types:
Info = {timetrap,Time} | {require,Required} | {require,Name,Required} | {userdata,UserData} |
{silent_connections,Conns} | {stylesheet,CSSFile} | {ct_hooks, CTHs}
Time = TimeVal | TimeFunc
TimeVal = MilliSec | {seconds,integer()} | {minutes,integer()} | {hours,integer()}
TimeFunc = {Mod,Func,Args} | Fun
MilliSec = integer()
Mod = atom()
Func = atom()
Args = list()
Fun = fun()
Required = Key | {Key,SubKeys} | {Key,Subkey} | {Key,Subkey,SubKeys}
Key = atom()
SubKeys = SubKey | [SubKey]
SubKey = atom()
Name = atom()
UserData = term()
Conns = [atom()]
CSSFile = string()
CTHs = [CTHModule |
{CTHModule, CTHInitArgs} |
{CTHModule, CTHInitArgs, CTHPriority}]
CTHModule = atom()
CTHInitArgs = term()
OPTIONAL
The test case group information function. It is supposed to return a list of tagged tuples that
specify various properties related to the execution of a test case group (that is, its test cases
and subgroups). Properties set by group/1 override properties with the same key that have been set
previously by suite/0.
Tag timetrap sets the maximum time that each test case is allowed to execute (including
init_per_testcase/2 and end_per_testcase/2). If the timetrap time is exceeded, the test case fails
with reason timetrap_timeout. A TimeFunc function can be used to set a new timetrap by returning a
TimeVal. It can also be used to trigger a timetrap time-out by, at some point, returning a value
other than a TimeVal. For details, see section Timetrap Time-Outs in the User's Guide.
Tag require specifies configuration variables required by test cases (or configuration functions)
in the suite. If the required configuration variables are not found in any of the configuration
files, all test cases in this group are skipped. For details about the require functionality, see
function ct:require/1,2.
With userdata, the user can specify any test case group related information that can be read by
calling ct:userdata/2.
Tag ct_hooks specifies the Common Test Hooks to be run with this suite.
Other tuples than the ones defined are ignored.
For details about the test case group information function, see section Group Information Function
in the User's Guide.
Module:init_per_group(GroupName, Config) -> NewConfig | {skip,Reason}
Types:
GroupName = atom()
Config = NewConfig = [{Key,Value}]
Key = atom()
Value = term()
Reason = term()
OPTIONAL; if this function is defined, then end_per_group/2 must also be defined.
This configuration function is called before execution of a test case group. It typically contains
initializations that are common for all test cases and subgroups in the group, and that must only
be performed once. GroupName is the name of the group, as specified in the group definition (see
groups/0). Parameter Config is the configuration data that can be modified. The return value of
this function is given as Config to all test cases and subgroups in the group.
If {skip,Reason} is returned, all test cases in the group are skipped and Reason is printed in the
overview log for the group.
For information about test case groups, see section Test Case Groups in the User's Guide.
Module:end_per_group(GroupName, Config) -> term() | {return_group_result,Status}
Types:
GroupName = atom()
Config = [{Key,Value}]
Key = atom()
Value = term()
Status = ok | skipped | failed
OPTIONAL; if this function is defined, then init_per_group/2 must also be defined.
This function is called after the execution of a test case group is finished. It is meant to be
used for cleaning up after init_per_group/2. A status value for a nested subgroup can be returned
with {return_group_result,Status}. The status can be retrieved in end_per_group/2 for the group on
the level above. The status is also used by Common Test for deciding if execution of a group is to
proceed if property sequence or repeat_until_* is set.
For details about test case groups, see section Test Case Groups in the User's Guide.
Module:init_per_testcase(TestCase, Config) -> NewConfig | {fail,Reason} | {skip,Reason}
Types:
TestCase = atom()
Config = NewConfig = [{Key,Value}]
Key = atom()
Value = term()
Reason = term()
OPTIONAL; if this function is defined, then end_per_testcase/2 must also be defined.
This function is called before each test case. Argument TestCase is the test case name, and Config
(list of key-value tuples) is the configuration data that can be modified. The NewConfig list
returned from this function is given as Config to the test case. If {fail,Reason} is returned, the
test case is marked as failed without being executed.
If {skip,Reason} is returned, the test case is skipped and Reason is printed in the overview log
for the suite.
Module:end_per_testcase(TestCase, Config) -> term() | {fail,Reason} | {save_config,SaveConfig}
Types:
TestCase = atom()
Config = SaveConfig = [{Key,Value}]
Key = atom()
Value = term()
Reason = term()
OPTIONAL; if this function is defined, then init_per_testcase/2 must also be defined.
This function is called after each test case, and can be used to clean up after
init_per_testcase/2 and the test case. Any return value (besides {fail,Reason} and
{save_config,SaveConfig}) is ignored. By returning {fail,Reason}, TestCase is marked as faulty
(even though it was successful in the sense that it returned a value instead of terminating).
For information on save_config, see section Saving Configuration Data in the User's Guide.
Module:Testcase() -> [Info]
Types:
Info = {timetrap,Time} | {require,Required} | {require,Name,Required} | {userdata,UserData} |
{silent_connections,Conns}
Time = TimeVal | TimeFunc
TimeVal = MilliSec | {seconds,integer()} | {minutes,integer()} | {hours,integer()}
TimeFunc = {Mod,Func,Args} | Fun
MilliSec = integer()
Mod = atom()
Func = atom()
Args = list()
Fun = fun()
Required = Key | {Key,SubKeys} | {Key,Subkey} | {Key,Subkey,SubKeys}
Key = atom()
SubKeys = SubKey | [SubKey]
SubKey = atom()
Name = atom()
UserData = term()
Conns = [atom()]
OPTIONAL
The test case information function. It is supposed to return a list of tagged tuples that specify
various properties related to the execution of this particular test case. Properties set by
Testcase/0 override properties set previously for the test case by group/1 or suite/0.
Tag timetrap sets the maximum time that the test case is allowed to execute. If the timetrap time
is exceeded, the test case fails with reason timetrap_timeout. init_per_testcase/2 and
end_per_testcase/2 are included in the timetrap time. A TimeFunc function can be used to set a new
timetrap by returning a TimeVal. It can also be used to trigger a timetrap time-out by, at some
point, returning a value other than a TimeVal. For details, see section Timetrap Time-Outs in the
User's Guide.
Tag require specifies configuration variables that are required by the test case (or
init_per_testcase/2 or end_per_testcase/2). If the required configuration variables are not found
in any of the configuration files, the test case is skipped. For details about the require
functionality, see function ct:require/1,2.
If timetrap or require is not set, the default values specified by suite/0 (or group/1) are used.
With userdata, the user can specify any test case-related information that can be read by calling
ct:userdata/3.
Other tuples than the ones defined are ignored.
For details about the test case information function, see section Test Case Information Function
in the User's Guide.
Module:Testcase(Config) -> term() | {skip,Reason} | {comment,Comment} | {save_config,SaveConfig} |
{skip_and_save,Reason,SaveConfig} | exit()
Types:
Config = SaveConfig = [{Key,Value}]
Key = atom()
Value = term()
Reason = term()
Comment = string()
MANDATORY
The implementation of a test case. Call the functions to test and check the result. If something
fails, ensure the function causes a runtime error or call ct:fail/1,2 (which also causes the test
case process to terminate).
Elements from the Config list can, for example, be read with proplists:get_value/2 in STDLIB (or
the macro ?config defined in ct.hrl).
If you decide not to run the test case after all, return {skip,Reason}. Reason is then printed in
field Comment on the HTML result page.
To print some information in field Comment on the HTML result page, return {comment,Comment}.
If the function returns anything else, the test case is considered successful. The return value
always gets printed in the test case log file.
For details about test case implementation, see section Test Cases in the User's Guide.
For information on save_config and skip_and_save, see section Saving Configuration Data in the
User's Guide.