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diff --git a/poky/documentation/test-manual/test-manual-intro.xml b/poky/documentation/test-manual/test-manual-intro.xml new file mode 100644 index 000000000..8e2c7cd87 --- /dev/null +++ b/poky/documentation/test-manual/test-manual-intro.xml @@ -0,0 +1,624 @@ +<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN" +"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd" +[<!ENTITY % poky SYSTEM "../poky.ent"> %poky; ] > +<!--SPDX-License-Identifier: CC-BY-2.0-UK--> + +<chapter id='test-manual-intro'> + +<title>The Yocto Project Test Environment Manual</title> + <section id='test-welcome'> + <title>Welcome</title> + + <para> Welcome to the Yocto Project Test Environment Manual! This manual is a work in + progress. The manual contains information about the testing environment used by the + Yocto Project to make sure each major and minor release works as intended. All the + project’s testing infrastructure and processes are publicly visible and available so + that the community can see what testing is being performed, how it’s being done and the + current status of the tests and the project at any given time. It is intended that Other + organizations can leverage off the process and testing environment used by the Yocto + Project to create their own automated, production test environment, building upon the + foundations from the project core. </para> + + <para> Currently, the Yocto Project Test Environment Manual has no projected release date. + This manual is a work-in-progress and is being initially loaded with information from + the <ulink url="">README</ulink> files and notes from key engineers: <itemizedlist> + <listitem> + <para> + <emphasis><filename>yocto-autobuilder2</filename>:</emphasis> This <ulink + url="http://git.yoctoproject.org/clean/cgit.cgi/yocto-autobuilder2/tree/README.md" + ><filename>README.md</filename></ulink> is the main README which + detials how to set up the Yocto Project Autobuilder. The + <filename>yocto-autobuilder2</filename> repository represents the Yocto + Project's console UI plugin to Buildbot and the configuration necessary to + configure Buildbot to perform the testing the project requires. </para> + </listitem> + <listitem> + <para> + <emphasis><filename>yocto-autobuilder-helper</filename>:</emphasis> This + <ulink + url="http://git.yoctoproject.org/clean/cgit.cgi/yocto-autobuilder-helper/tree/README" + ><filename>README</filename></ulink> and repository contains Yocto + Project Autobuilder Helper scripts and configuration. The + <filename>yocto-autobuilder-helper</filename> repository contains the + "glue" logic that defines which tests to run and how to run them. As a + result, it can be used by any Continuous Improvement (CI) system to run + builds, support getting the correct code revisions, configure builds and + layers, run builds, and collect results. The code is independent of any CI + system, which means the code can work Buildbot, Jenkins, or others. This + repository has a branch per release of the project defining the tests to run + on a per release basis.</para> + </listitem> + </itemizedlist> + </para> + </section> + + <section id='test-yocto-project-autobuilder-overview'> + <title>Yocto Project Autobuilder Overview</title> + + <para>The Yocto Project Autobuilder collectively refers to the software, tools, scripts, and + procedures used by the Yocto Project to test released software across supported hardware + in an automated and regular fashion. Basically, during the development of a Yocto + Project release, the Autobuilder tests if things work. The Autobuilder builds all test + targets and runs all the tests. </para> + + <para>The Yocto Project uses now uses standard upstream <ulink + url="https://docs.buildbot.net/0.9.15.post1/">Buildbot</ulink> (version 9) to drive + its integration and testing. Buildbot Nine has a plug-in interface that the Yocto + Project customizes using code from the <filename>yocto-autobuilder2</filename> + repository, adding its own console UI plugin. The resulting UI plug-in allows you to + visualize builds in a way suited to the project's needs.</para> + + <para>A <filename>helper</filename> layer provides configuration and job management through + scripts found in the <filename>yocto-autobuilder-helper</filename> repository. The + <filename>helper</filename> layer contains the bulk of the build configuration + information and is release-specific, which makes it highly customizable on a per-project + basis. The layer is CI system-agnostic and contains a number of Helper scripts that can + generate build configurations from simple JSON files. <note> + <para>The project uses Buildbot for historical reasons but also because many of the + project developers have knowledge of python. It is possible to use the outer + layers from another Continuous Integration (CI) system such as <ulink + url="https://en.wikipedia.org/wiki/Jenkins_(software)">Jenkins</ulink> + instead of Buildbot. </para> + </note> + </para> + + <para> The following figure shows the Yocto Project Autobuilder stack with a topology that + includes a controller and a cluster of workers: <imagedata + fileref="figures/ab-test-cluster.png" width="4.6in" depth="4.35in" align="center" + scalefit="1"/> + </para> + </section> + + <section id='test-project-tests'> + <title>Yocto Project Tests - Types of Testing Overview</title> + + <para>The Autobuilder tests different elements of the project by using thefollowing types of + tests: <itemizedlist> + <listitem> + <para> + <emphasis>Build Testing:</emphasis> Tests whether specific configurations + build by varying <ulink url="&YOCTO_DOCS_REF_URL;#var-MACHINE" + ><filename>MACHINE</filename></ulink>, <ulink + url="&YOCTO_DOCS_REF_URL;#var-DISTRO" + ><filename>DISTRO</filename></ulink>, other configuration options, and + the specific target images being built (or world). Used to trigger builds of + all the different test configurations on the Autobuilder. Builds usually + cover many different targets for different architectures, machines, and + distributions, as well as different configurations, such as different init + systems. The Autobuilder tests literally hundreds of configurations and + targets. <itemizedlist> + <listitem> + <para> + <emphasis>Sanity Checks During the Build Process:</emphasis> + Tests initiated through the <ulink + url="&YOCTO_DOCS_REF_URL;#ref-classes-insane" + ><filename>insane</filename></ulink> class. These checks + ensure the output of the builds are correct. For example, does + the ELF architecture in the generated binaries match the target + system? ARM binaries would not work in a MIPS system! </para> + </listitem> + </itemizedlist></para> + </listitem> + <listitem> + <para> + <emphasis>Build Performance Testing:</emphasis> Tests whether or not + commonly used steps during builds work efficiently and avoid regressions. + Tests to time commonly used usage scenarios are run through + <filename>oe-build-perf-test</filename>. These tests are run on isolated + machines so that the time measurements of the tests are accurate and no + other processes interfere with the timing results. The project currently + tests performance on two different distributions, Fedora and Ubuntu, to + ensure we have no single point of failure and can ensure the different + distros work effectively. </para> + </listitem> + <listitem> + <para> + <emphasis>eSDK Testing:</emphasis> Image tests initiated through the + following command: + <literallayout class="monospaced"> + $ bitbake <replaceable>image</replaceable> -c testsdkext + </literallayout> + The tests utilize the <filename>testsdkext</filename> class and the + <filename>do_testsdkext</filename> task. </para> + </listitem> + <listitem> + <para> + <emphasis>Feature Testing:</emphasis> Various scenario-based tests are run + through the <ulink url="&YOCTO_DOCS_REF_URL;#testing-and-quality-assurance" + >OpenEmbedded Self-Test</ulink> (oe-selftest). We test oe-selftest on + each of the main distrubutions we support. </para> + </listitem> + <listitem> + <para> + <emphasis>Image Testing:</emphasis> Image tests initiated through the + following command: + <literallayout class="monospaced"> + $ bitbake <replaceable>image</replaceable> -c testimage + </literallayout> + The tests utilize the <ulink + url="&YOCTO_DOCS_REF_URL;#ref-classes-testimage*" + ><filename>testimage*</filename></ulink> classes and the <ulink + url="&YOCTO_DOCS_REF_URL;#ref-tasks-testimage" + ><filename>do_testimage</filename></ulink> task. </para> + </listitem> + <listitem> + <para> + <emphasis>Layer Testing:</emphasis> The Autobuilder has the possibility to + test whether specific layers work with the test of the system. The layers + tested may be selected by members of the project. Some key community layers + are also tested periodically.</para> + </listitem> + <listitem> + <para> + <emphasis>Package Testing:</emphasis> A Package Test (ptest) runs tests + against packages built by the OpenEmbedded build system on the target + machine. See the "<ulink + url="&YOCTO_DOCS_DEV_URL;#testing-packages-with-ptest">Testing Packages + With ptest</ulink>" section in the Yocto Project Development Tasks + Manual and the "<ulink url="&YOCTO_WIKI_URL;/wiki/Ptest">Ptest</ulink>" Wiki + page for more information on Ptest. </para> + </listitem> + <listitem> + <para> + <emphasis>SDK Testing:</emphasis> Image tests initiated through the + following command: + <literallayout class="monospaced"> + $ bitbake <replaceable>image</replaceable> -c testsdk + </literallayout> + The tests utilize the <ulink url="&YOCTO_DOCS_REF_URL;#ref-classes-testsdk" + ><filename>testsdk</filename></ulink> class and the + <filename>do_testsdk</filename> task. </para> + </listitem> + <listitem> + <para> + <emphasis>Unit Testing:</emphasis> Unit tests on various components of the + system run through <filename>oe-selftest</filename> and <ulink + url="&YOCTO_DOCS_REF_URL;#testing-and-quality-assurance" + ><filename>bitbake-selftest</filename></ulink>. </para> + </listitem> + <listitem> + <para> + <emphasis>Automatic Upgrade Helper:</emphasis> This target tests whether new + versions of software are available and whether we can automatically upgrade + to those new versions. If so, this target emails the maintainers with a + patch to let them know this is possible.</para> + </listitem> + </itemizedlist> + </para> + </section> + + <section id='test-test-mapping'> + <title>How Tests Map to Areas of Code</title> + + <para> + Tests map into the codebase as follows: + <itemizedlist> + <listitem><para> + <emphasis>bitbake-selftest</emphasis>: </para> + <para>These tests are self-contained and test BitBake as well as its APIs, which + include the fetchers. The tests are located in + <filename>bitbake/lib/*/tests</filename>. </para> + <para>From within the BitBake repository, run the following: + <literallayout class="monospaced"> + $ bitbake-selftest + </literallayout> + </para> + <para>To skip tests that access the Internet, use the + <filename>BB_SKIP_NETTEST</filename> variable when running + "bitbake-selftest" as follows: + <literallayout class="monospaced"> + $ BB_SKIP_NETTEST=yes bitbake-selftest + </literallayout></para> + <para>The default output is quiet and just prints a summary of what was run. To + see more information, there is a verbose + option:<literallayout class="monospaced"> + $ bitbake-selftest -v + </literallayout></para> + <para>Use this option when you wish to skip tests that access the network, which + are mostly necessary to test the fetcher modules. To specify individual test + modules to run, append the test module name to the "bitbake-selftest" + command. For example, to specify the tests for the bb.data.module, run: + <literallayout class="monospaced"> + $ bitbake-selftest bb.test.data.module + </literallayout>You + can also specify individual tests by defining the full name and module plus + the class path of the test, for example: + <literallayout class="monospaced"> + $ bitbake-selftest bb.tests.data.TestOverrides.test_one_override + </literallayout></para> + <para>The tests are based on <ulink + url="https://docs.python.org/3/library/unittest.html">Python + unittest</ulink>. </para></listitem> + <listitem><para> + <emphasis>oe-selftest</emphasis>: <itemizedlist> + <listitem> + <para>These tests use OE to test the workflows, which include + testing specific features, behaviors of tasks, and API unit + tests. </para> + </listitem> + <listitem> + <para>The tests can take advantage of parallelism through the "-j" + option, which can specify a number of threads to spread the + tests across. Note that all tests from a given class of tests + will run in the same thread. To parallelize large numbers of + tests you can split the class into multiple units.</para> + </listitem> + <listitem> + <para>The tests are based on Python unittest. </para> + </listitem> + <listitem> + <para>The code for the tests resides in + <filename>meta/lib/oeqa/selftest/cases/</filename>. </para> + </listitem> + <listitem> + <para>To run all the tests, enter the following command: + <literallayout class="monospaced"> + $ oe-selftest -a + </literallayout> + </para> + </listitem> + <listitem> + <para>To run a specific test, use the following command form where + <replaceable>testname</replaceable> is the name of the + specific test: + <literallayout class="monospaced"> + $ oe-selftest -r <replaceable>testname</replaceable> + </literallayout> + For example, the following command would run the tinfoil getVar + API + test:<literallayout class="monospaced"> + $ oe-selftest -r tinfoil.TinfoilTests.test_getvar + </literallayout>It + is also possible to run a set of tests. For example the + following command will run all of the tinfoil + tests:<literallayout class="monospaced"> + $ oe-selftest -r tinfoil + </literallayout></para> + </listitem> + </itemizedlist> + </para></listitem> + <listitem><para> + <emphasis>testimage:</emphasis> + <itemizedlist> + <listitem><para> + These tests build an image, boot it, and run tests + against the image's content. + </para></listitem> + <listitem><para> The code for these tests resides in <filename>meta/lib/oeqa/runtime/cases/</filename>. </para></listitem> + <listitem><para> + You need to set the + <ulink url='&YOCTO_DOCS_REF_URL;#var-IMAGE_CLASSES'><filename>IMAGE_CLASSES</filename></ulink> + variable as follows: + <literallayout class='monospaced'> + IMAGE_CLASSES += "testimage" + </literallayout> + </para></listitem> + <listitem><para> + Run the tests using the following command form: + <literallayout class='monospaced'> + $ bitbake <replaceable>image</replaceable> -c testimage + </literallayout> + </para></listitem> + </itemizedlist> + </para></listitem> + <listitem><para> + <emphasis>testsdk:</emphasis> + <itemizedlist> + <listitem><para>These tests build an SDK, install it, and then run tests against that SDK. </para></listitem> + <listitem><para>The code for these tests resides in <filename>meta/lib/oeqa/sdk/cases/</filename>. </para></listitem> + <listitem><para>Run the test using the following command form: + <literallayout class="monospaced"> + $ bitbake <replaceable>image</replaceable> -c testsdk + </literallayout> + </para></listitem> + </itemizedlist> + </para></listitem> + <listitem><para> + <emphasis>testsdk_ext:</emphasis> + <itemizedlist> + <listitem><para>These tests build an extended SDK (eSDK), install that eSDK, and run tests against the eSDK. </para></listitem> + <listitem><para>The code for these tests resides in <filename>meta/lib/oeqa/esdk</filename>. </para></listitem> + <listitem><para>To run the tests, use the following command form: + <literallayout class="monospaced"> + $ bitbake <replaceable>image</replaceable> -c testsdkext + </literallayout> + </para></listitem> + </itemizedlist> + </para></listitem> + + + <listitem><para> + <emphasis>oe-build-perf-test:</emphasis> + <itemizedlist> + <listitem><para>These tests run through commonly used usage scenarios and measure the performance times. </para></listitem> + <listitem><para>The code for these tests resides in <filename>meta/lib/oeqa/buildperf</filename>. </para></listitem> + <listitem><para>To run the tests, use the following command form: + <literallayout class="monospaced"> + $ oe-build-perf-test <replaceable>options</replaceable> + </literallayout>The + command takes a number of options, such as where to place the + test results. The Autobuilder Helper Scripts include the + <filename>build-perf-test-wrapper</filename> script with + examples of how to use the oe-build-perf-test from the command + line.</para> + <para>Use the <filename>oe-git-archive</filename> command to store + test results into a Git repository. </para> + <para>Use the <filename>oe-build-perf-report</filename> command to + generate text reports and HTML reports with graphs of the + performance data. For examples, see <link linkend="" + >http://downloads.yoctoproject.org/releases/yocto/yocto-2.7/testresults/buildperf-centos7/perf-centos7.yoctoproject.org_warrior_20190414204758_0e39202.html</link> + and <link linkend="" + >http://downloads.yoctoproject.org/releases/yocto/yocto-2.7/testresults/buildperf-centos7/perf-centos7.yoctoproject.org_warrior_20190414204758_0e39202.txt</link>.</para></listitem> + <listitem> + <para>The tests are contained in + <filename>lib/oeqa/buildperf/test_basic.py</filename>.</para> + </listitem> + </itemizedlist> + </para></listitem> + + + + + </itemizedlist> + </para> + </section> + + <section id='test-examples'> + <title>Test Examples</title> + + <para>This section provides example tests for each of the tests listed in the <link + linkend="test-test-mapping">How Tests Map to Areas of Code</link> section. </para> + <para>For oeqa tests, testcases for each area reside in the main test directory at + <filename>meta/lib/oeqa/selftest/cases</filename> directory.</para> + <para>For oe-selftest. bitbake testcases reside in the <filename>lib/bb/tests/</filename> + directory. </para> + + <section id='bitbake-selftest-example'> + <title><filename>bitbake-selftest</filename></title> + + <para>A simple test example from <filename>lib/bb/tests/data.py</filename> is: + <literallayout class="monospaced"> + class DataExpansions(unittest.TestCase): + def setUp(self): + self.d = bb.data.init() + self.d["foo"] = "value_of_foo" + self.d["bar"] = "value_of_bar" + self.d["value_of_foo"] = "value_of_'value_of_foo'" + + def test_one_var(self): + val = self.d.expand("${foo}") + self.assertEqual(str(val), "value_of_foo") + </literallayout> + </para> + <para>In this example, a <ulink url=""><filename>DataExpansions</filename></ulink> class + of tests is created, derived from standard python unittest. The class has a common + <filename>setUp</filename> function which is shared by all the tests in the + class. A simple test is then added to test that when a variable is expanded, the + correct value is found.</para> + <para>Bitbake selftests are straightforward python unittest. Refer to the Python + unittest documentation for additional information on writing these tests at: <link + linkend="">https://docs.python.org/3/library/unittest.html</link>.</para> + </section> + + <section id='oe-selftest-example'> + <title><filename>oe-selftest</filename></title> + + <para>These tests are more complex due to the setup required behind the scenes for full + builds. Rather than directly using Python's unittest, the code wraps most of the + standard objects. The tests can be simple, such as testing a command from within the + OE build environment using the following + example:<literallayout class="monospaced"> + class BitbakeLayers(OESelftestTestCase): + def test_bitbakelayers_showcrossdepends(self): + result = runCmd('bitbake-layers show-cross-depends') + self.assertTrue('aspell' in result.output, msg = "No dependencies + were shown. bitbake-layers show-cross-depends output: + %s"% result.output) + </literallayout></para> + <para>This example, taken from + <filename>meta/lib/oeqa/selftest/cases/bblayers.py</filename>, creates a + testcase from the <ulink url=""><filename>OESelftestTestCase</filename></ulink> + class, derived from <filename>unittest.TestCase</filename>, which runs the + <filename>bitbake-layers</filename> command and checks the output to ensure it + contains something we know should be here.</para> + <para>The <filename>oeqa.utils.commands</filename> module contains Helpers which can + assist with common tasks, including:<itemizedlist> + <listitem> + <para><emphasis>Obtaining the value of a bitbake variable:</emphasis> Use + <filename>oeqa.utils.commands.get_bb_var()</filename> or use + <filename>oeqa.utils.commands.get_bb_vars()</filename> for more than + one variable</para> + </listitem> + <listitem> + <para><emphasis>Running a bitbake invocation for a build:</emphasis> Use + <filename>oeqa.utils.commands.bitbake()</filename></para> + </listitem> + <listitem> + <para><emphasis>Running a command:</emphasis> Use + <filename>oeqa.utils.commandsrunCmd()</filename></para> + </listitem> + </itemizedlist></para> + <para>There is also a <filename>oeqa.utils.commands.runqemu()</filename> function for + launching the <filename>runqemu</filename> command for testing things within a + running, virtualized image.</para> + <para>You can run these tests in parallel. Parallelism works per test class, so tests + within a given test class should always run in the same build, while tests in + different classes or modules may be split into different builds. There is no data + store available for these tests since the tests launch the + <filename>bitbake</filename> command and exist outside of its context. As a + result, common bitbake library functions (bb.*) are also unavailable.</para> + </section> + + <section id='testimage-example'> + <title><filename>testimage</filename></title> + + <para>These tests are run once an image is up and running, either on target hardware or + under QEMU. As a result, they are assumed to be running in a target image + environment, as opposed to a host build environment. A simple example from + <filename>meta/lib/oeqa/runtime/cases/python.py</filename> contains the + following:<literallayout class="monospaced"> + class PythonTest(OERuntimeTestCase): + @OETestDepends(['ssh.SSHTest.test_ssh']) + @OEHasPackage(['python3-core']) + def test_python3(self): + cmd = "python3 -c \"import codecs; print(codecs.encode('Uryyb, + jbeyq', 'rot13'))\"" + status, output = self.target.run(cmd) + msg = 'Exit status was not 0. Output: %s' % output + self.assertEqual(status, 0, msg=msg) + </literallayout></para> + <para>In this example, the <ulink url=""><filename>OERuntimeTestCase</filename></ulink> + class wraps <filename>unittest.TestCase</filename>. Within the test, + <filename>self.target</filename> represents the target system, where commands + can be run on it using the <filename>run()</filename> method. </para> + <para>To ensure certain test or package dependencies are met, you can use the + <filename>OETestDepends</filename> and <filename>OEHasPackage</filename> + decorators. For example, the test in this example would only make sense if + python3-core is installed in the image.</para> + </section> + + <section id='testsdk_ext-example'> + <title><filename>testsdk_ext</filename></title> + + <para>These tests are run against built extensible SDKs (eSDKs). The tests can assume + that the eSDK environment has already been setup. An example from + <filename>meta/lib/oeqa/sdk/cases/devtool.py</filename> contains the + following:<literallayout class="monospaced"> + class DevtoolTest(OESDKExtTestCase): + @classmethod + def setUpClass(cls): + myapp_src = os.path.join(cls.tc.esdk_files_dir, "myapp") + cls.myapp_dst = os.path.join(cls.tc.sdk_dir, "myapp") + shutil.copytree(myapp_src, cls.myapp_dst) + subprocess.check_output(['git', 'init', '.'], cwd=cls.myapp_dst) + subprocess.check_output(['git', 'add', '.'], cwd=cls.myapp_dst) + subprocess.check_output(['git', 'commit', '-m', "'test commit'"], cwd=cls.myapp_dst) + + @classmethod + def tearDownClass(cls): + shutil.rmtree(cls.myapp_dst) + def _test_devtool_build(self, directory): + self._run('devtool add myapp %s' % directory) + try: + self._run('devtool build myapp') + finally: + self._run('devtool reset myapp') + def test_devtool_build_make(self): + self._test_devtool_build(self.myapp_dst) + </literallayout>In + this example, the <filename>devtool</filename> command is tested to see whether a + sample application can be built with the <filename>devtool build</filename> command + within the eSDK.</para> + </section> + + <section id='testsdk-example'> + <title><filename>testsdk</filename></title> + + <para>These tests are run against built SDKs. The tests can assume that an SDK has + already been extracted and its environment file has been sourced. A simple example + from <filename>meta/lib/oeqa/sdk/cases/python2.py</filename> contains the + following:<literallayout class="monospaced"> + class Python3Test(OESDKTestCase): + def setUp(self): + if not (self.tc.hasHostPackage("nativesdk-python3-core") or + self.tc.hasHostPackage("python3-core-native")): + raise unittest.SkipTest("No python3 package in the SDK") + + def test_python3(self): + cmd = "python3 -c \"import codecs; print(codecs.encode('Uryyb, jbeyq', 'rot13'))\"" + output = self._run(cmd) + self.assertEqual(output, "Hello, world\n") + </literallayout>In + this example, if nativesdk-python3-core has been installed into the SDK, the code + runs the python3 interpreter with a basic command to check it is working correctly. + The test would only run if python3 is installed in the SDK.</para> + </section> + + <section id='oe-build-perf-test-example'> + <title><filename>oe-build-perf-test</filename></title> + + <para>The performance tests usually measure how long operations take and the resource + utilisation as that happens. An example from + <filename>meta/lib/oeqa/buildperf/test_basic.py</filename> contains the + following:<literallayout class="monospaced"> + class Test3(BuildPerfTestCase): + + def test3(self): + """Bitbake parsing (bitbake -p)""" + # Drop all caches and parse + self.rm_cache() + oe.path.remove(os.path.join(self.bb_vars['TMPDIR'], 'cache'), True) + self.measure_cmd_resources(['bitbake', '-p'], 'parse_1', + 'bitbake -p (no caches)') + # Drop tmp/cache + oe.path.remove(os.path.join(self.bb_vars['TMPDIR'], 'cache'), True) + self.measure_cmd_resources(['bitbake', '-p'], 'parse_2', + 'bitbake -p (no tmp/cache)') + # Parse with fully cached data + self.measure_cmd_resources(['bitbake', '-p'], 'parse_3', + 'bitbake -p (cached)') + </literallayout>This + example shows how three specific parsing timings are measured, with and without + various caches, to show how BitBake’s parsing performance trends over time.</para> + </section> + </section> + <section id='test-writing-considerations'> + <title>Considerations When Writing Tests</title> + <para>When writing good tests, there are several things to keep in mind. Since things + running on the Autobuilder are accessed concurrently by multiple workers, consider the + following:</para> + <formalpara> + <title>Running "cleanall" is not permitted</title> + <para>This can delete files from DL_DIR which would potentially break other builds + running in parallel. If this is required, DL_DIR must be set to an isolated + directory.</para> + </formalpara> + <formalpara> + <title>Running "cleansstate" is not permitted</title> + <para>This can delete files from SSTATE_DIR which would potentially break other builds + running in parallel. If this is required, SSTATE_DIR must be set to an isolated + directory. Alternatively, you can use the "-f" option with the + <filename>bitbake</filename> command to "taint" tasks by changing the sstate + checksums to ensure sstate cache items will not be reused.</para> + </formalpara> + <formalpara> + <title>Tests should not change the metadata</title> + <para>This is particularly true for oe-selftests since these can run in parallel and + changing metadata leads to changing checksums, which confuses BitBake while running + in parallel. If this is necessary, copy layers to a temporary location and modify + them. Some tests need to change metadata, such as the devtool tests. To prevent the + metadate from changes, set up temporary copies of that data first.</para> + </formalpara> + </section> + + + + + + + + +</chapter> +<!-- +vim: expandtab tw=80 ts=4 +--> |