View Source ct_property_test (common_test v1.27)
Support in Common Test for running property-based tests.
This module helps running property-based tests in the Common Test
framework.
One (or more) of the property testing tools
is assumed to be installed.
The idea with this module is to have a Common Test
test suite calling a
property testing tool with special property test suites as defined by that tool.
The tests are collected in the test
directory of the application. The test
directory has a subdirectory property_test
, where everything needed for the
property tests are collected. The usual Erlang application directory structure
is assumed.
A typical Common Test
test suite using ct_property_test
is organized as
follows:
-module(my_prop_test_SUITE).
-compile(export_all).
-include_lib("common_test/include/ct.hrl").
all() -> [prop_ftp_case].
init_per_suite(Config) ->
ct_property_test:init_per_suite(Config).
%%%---- test case
prop_ftp_case(Config) ->
ct_property_test:quickcheck(
ftp_simple_client_server:prop_ftp(),
Config
).
and the the property test module (in this example
ftp_simple_client_server.erl
) as almost a usual property testing module (More
examples are in the User's Guide):
-module(ftp_simple_client_server).
-export([prop_ftp/0...]).
-include_lib("common_test/include/ct_property_test.hrl").
prop_ftp() ->
?FORALL( ....
Summary
Functions
init_per_suite(Config) -> Config | {skip, Reason}
present_result(Module, Cmds, Triple, Config) -> Result
present_result(Module, Cmds, Triple, Config, Options) -> Result
quickcheck(Property, Config) -> true | {fail, Reason}
Functions
init_per_suite(Config) -> Config | {skip, Reason}
Initializes and extends Config
for property based testing.
This function investigates if support is available for either
QuickCheck, PropEr
or Triq and compiles the properties with
the first tool found. It is supposed to be called in the
init_per_suite/1
function in a CommonTest test suite.
Which tools to check for, and in which order could be set with the option
{prop_tools, list(eqc|proper|triq)}
in the CommonTest configuration Config
.
The default value is [eqc, proper, triq]
with eqc
being the first one
searched for.
If no support is found for any tool, this function returns
{skip, Explanation}
.
If support is found, the option {property_test_tool,ToolModule}
with the
selected tool main module name (eqc
, proper
or triq
) is added to the list
Config
which then is returned.
The property tests are assumed to be in a subdirectory named property_test
.
All found Erlang files in that directory are compiled with one of the macros
'EQC'
, 'PROPER'
or 'TRIQ'
set, depending on which tool that is first
found. This could make parts of the Erlang property tests code to be included or
excluded with the macro directives -ifdef(Macro).
or -ifndef(Macro).
.
The file(s) in the property_test
subdirectory could, or should, include the
ct_property_test include file:
-include_lib("common_test/include/ct_property_test.hrl").
This included file will:
- Include the correct tool's include file
- Set the macro
'MOD_eqc'
to the correct module name for the selected tool. That is, the macro'MOD_eqc'
is set to eithereqc
,proper
ortriq
.
present_result(Module, Cmds, Triple, Config) -> Result
present_result(Module, Cmds, Triple, Config, Options) -> Result
Presents the result of stateful (statem) property testing using the aggregate function in PropEr, QuickCheck or other similar property testing tool.
It is assumed to be called inside the property called by quickcheck/2
:
...
RunResult = run_parallel_commands(?MODULE, Cmds),
ct_property_test:present_result(?MODULE, Cmds, RunResult, Config)
...
See the User's Guide for an example of the usage and of the default printout.
The StatisticsSpec
is a list of the tuples:
{Title::string(), CollectFun::fun/1}
{Title::string(), FrequencyFun::/0, CollectFun::fun/1}
Each tuple will produce one table in the order of their places in the list.
Title
will be the title of one result tableCollectFun
is called with one argument: theCmds
. It should return a list of the values to be counted. The following pre-defined functions exist:ct_property_test:cmnd_names/1
returns a list of commands (function calls) generated in theCmnd
sequence, without Module, Arguments and other details.ct_property_test:num_calls/1
returns a list of the length of commands listsct_property_test:sequential_parallel/1
returns a list with information about sequential and parallel parts fromTool:parallel_commands/1,2
FrequencyFun/0
returns a fun/1 which is supposed to take a list of items as input, and return an iolist which will be printed as the table. Per default, the number of each item is counted and the percentage is printed for each. The list [a,b,a,a,c] could for example return["a 60%\n","b 20%\n","c 20%\n"]
which will be printed by the
print_fun
. The defaultprint_fun
will print it as:a 60% b 20% c 20%
The default StatisticsSpec
is:
For sequential commands:
[{"Function calls", fun cmnd_names/1}, {"Length of command sequences", fun print_frequency_ranges/0, fun num_calls/1}]
For parallel commands:
[{"Distribution sequential/parallel", fun sequential_parallel/1}, {"Function calls", fun cmnd_names/1}, {"Length of command sequences", fun print_frequency_ranges/0, fun num_calls/1}]
quickcheck(Property, Config) -> true | {fail, Reason}
Calls the selected tool's function for running the Property
. It is usually and
by historical reasons called quickcheck, and that is why that name is used in
this module (ct_property_test
).
The result is returned in a form suitable for Common Test
test suites.
This function is intended to be called in test cases in test suites.