mirror of
https://git.postgresql.org/git/postgresql.git
synced 2024-09-28 00:11:53 +02:00
78ee60ed84
This doesn't have any external effect at the moment, but it will allow adding useful link-discoverability features later. Brar Piening, reviewed by Karl Pinc. Discussion: https://postgr.es/m/CAB8KJ=jpuQU9QJe4+RgWENrK5g9jhoysMw2nvTN_esoOU0=a_w@mail.gmail.com
878 lines
34 KiB
Plaintext
878 lines
34 KiB
Plaintext
<!-- doc/src/sgml/regress.sgml -->
|
|
|
|
<chapter id="regress">
|
|
<title>Regression Tests</title>
|
|
|
|
<indexterm zone="regress">
|
|
<primary>regression tests</primary>
|
|
</indexterm>
|
|
|
|
<indexterm zone="regress">
|
|
<primary>test</primary>
|
|
</indexterm>
|
|
|
|
<para>
|
|
The regression tests are a comprehensive set of tests for the SQL
|
|
implementation in <productname>PostgreSQL</productname>. They test
|
|
standard SQL operations as well as the extended capabilities of
|
|
<productname>PostgreSQL</productname>.
|
|
</para>
|
|
|
|
<sect1 id="regress-run">
|
|
<title>Running the Tests</title>
|
|
|
|
<para>
|
|
The regression tests can be run against an already installed and
|
|
running server, or using a temporary installation within the build
|
|
tree. Furthermore, there is a <quote>parallel</quote> and a
|
|
<quote>sequential</quote> mode for running the tests. The
|
|
sequential method runs each test script alone, while the
|
|
parallel method starts up multiple server processes to run groups
|
|
of tests in parallel. Parallel testing adds confidence that
|
|
interprocess communication and locking are working correctly.
|
|
</para>
|
|
|
|
<sect2 id="regress-run-temp-inst">
|
|
<title>Running the Tests Against a Temporary Installation</title>
|
|
|
|
<para>
|
|
To run the parallel regression tests after building but before installation,
|
|
type:
|
|
<screen>
|
|
make check
|
|
</screen>
|
|
in the top-level directory. (Or you can change to
|
|
<filename>src/test/regress</filename> and run the command there.)
|
|
At the end you should see something like:
|
|
<screen>
|
|
<computeroutput>
|
|
=======================
|
|
All 193 tests passed.
|
|
=======================
|
|
</computeroutput>
|
|
</screen>
|
|
or otherwise a note about which tests failed. See <xref
|
|
linkend="regress-evaluation"/> below before assuming that a
|
|
<quote>failure</quote> represents a serious problem.
|
|
</para>
|
|
|
|
<para>
|
|
Because this test method runs a temporary server, it will not work
|
|
if you did the build as the root user, since the server will not start as
|
|
root. Recommended procedure is not to do the build as root, or else to
|
|
perform testing after completing the installation.
|
|
</para>
|
|
|
|
<para>
|
|
If you have configured <productname>PostgreSQL</productname> to install
|
|
into a location where an older <productname>PostgreSQL</productname>
|
|
installation already exists, and you perform <literal>make check</literal>
|
|
before installing the new version, you might find that the tests fail
|
|
because the new programs try to use the already-installed shared
|
|
libraries. (Typical symptoms are complaints about undefined symbols.)
|
|
If you wish to run the tests before overwriting the old installation,
|
|
you'll need to build with <literal>configure --disable-rpath</literal>.
|
|
It is not recommended that you use this option for the final installation,
|
|
however.
|
|
</para>
|
|
|
|
<para>
|
|
The parallel regression test starts quite a few processes under your
|
|
user ID. Presently, the maximum concurrency is twenty parallel test
|
|
scripts, which means forty processes: there's a server process and a
|
|
<application>psql</application> process for each test script.
|
|
So if your system enforces a per-user limit on the number of processes,
|
|
make sure this limit is at least fifty or so, else you might get
|
|
random-seeming failures in the parallel test. If you are not in
|
|
a position to raise the limit, you can cut down the degree of parallelism
|
|
by setting the <literal>MAX_CONNECTIONS</literal> parameter. For example:
|
|
<screen>
|
|
make MAX_CONNECTIONS=10 check
|
|
</screen>
|
|
runs no more than ten tests concurrently.
|
|
</para>
|
|
</sect2>
|
|
|
|
<sect2 id="regress-run-existing-inst">
|
|
<title>Running the Tests Against an Existing Installation</title>
|
|
|
|
<para>
|
|
To run the tests after installation (see <xref linkend="installation"/>),
|
|
initialize a data directory and start the
|
|
server as explained in <xref linkend="runtime"/>, then type:
|
|
<screen>
|
|
make installcheck
|
|
</screen>
|
|
or for a parallel test:
|
|
<screen>
|
|
make installcheck-parallel
|
|
</screen>
|
|
The tests will expect to contact the server at the local host and the
|
|
default port number, unless directed otherwise by <envar>PGHOST</envar> and
|
|
<envar>PGPORT</envar> environment variables. The tests will be run in a
|
|
database named <literal>regression</literal>; any existing database by this name
|
|
will be dropped.
|
|
</para>
|
|
|
|
<para>
|
|
The tests will also transiently create some cluster-wide objects, such as
|
|
roles, tablespaces, and subscriptions. These objects will have names
|
|
beginning with <literal>regress_</literal>. Beware of
|
|
using <literal>installcheck</literal> mode with an installation that has
|
|
any actual global objects named that way.
|
|
</para>
|
|
</sect2>
|
|
|
|
<sect2 id="regress-additional">
|
|
<title>Additional Test Suites</title>
|
|
|
|
<para>
|
|
The <literal>make check</literal> and <literal>make installcheck</literal> commands
|
|
run only the <quote>core</quote> regression tests, which test built-in
|
|
functionality of the <productname>PostgreSQL</productname> server. The source
|
|
distribution contains many additional test suites, most of them having
|
|
to do with add-on functionality such as optional procedural languages.
|
|
</para>
|
|
|
|
<para>
|
|
To run all test suites applicable to the modules that have been selected
|
|
to be built, including the core tests, type one of these commands at the
|
|
top of the build tree:
|
|
<screen>
|
|
make check-world
|
|
make installcheck-world
|
|
</screen>
|
|
These commands run the tests using temporary servers or an
|
|
already-installed server, respectively, just as previously explained
|
|
for <literal>make check</literal> and <literal>make installcheck</literal>. Other
|
|
considerations are the same as previously explained for each method.
|
|
Note that <literal>make check-world</literal> builds a separate instance
|
|
(temporary data directory) for each tested module, so it requires more
|
|
time and disk space than <literal>make installcheck-world</literal>.
|
|
</para>
|
|
|
|
<para>
|
|
On a modern machine with multiple CPU cores and no tight operating-system
|
|
limits, you can make things go substantially faster with parallelism.
|
|
The recipe that most PostgreSQL developers actually use for running all
|
|
tests is something like
|
|
<screen>
|
|
make check-world -j8 >/dev/null
|
|
</screen>
|
|
with a <option>-j</option> limit near to or a bit more than the number
|
|
of available cores. Discarding <systemitem>stdout</systemitem>
|
|
eliminates chatter that's not interesting when you just want to verify
|
|
success. (In case of failure, the <systemitem>stderr</systemitem>
|
|
messages are usually enough to determine where to look closer.)
|
|
</para>
|
|
|
|
<para>
|
|
Alternatively, you can run individual test suites by typing
|
|
<literal>make check</literal> or <literal>make installcheck</literal> in the appropriate
|
|
subdirectory of the build tree. Keep in mind that <literal>make
|
|
installcheck</literal> assumes you've installed the relevant module(s), not
|
|
only the core server.
|
|
</para>
|
|
|
|
<para>
|
|
The additional tests that can be invoked this way include:
|
|
</para>
|
|
|
|
<itemizedlist>
|
|
<listitem>
|
|
<para>
|
|
Regression tests for optional procedural languages.
|
|
These are located under <filename>src/pl</filename>.
|
|
</para>
|
|
</listitem>
|
|
<listitem>
|
|
<para>
|
|
Regression tests for <filename>contrib</filename> modules,
|
|
located under <filename>contrib</filename>.
|
|
Not all <filename>contrib</filename> modules have tests.
|
|
</para>
|
|
</listitem>
|
|
<listitem>
|
|
<para>
|
|
Regression tests for the ECPG interface library,
|
|
located in <filename>src/interfaces/ecpg/test</filename>.
|
|
</para>
|
|
</listitem>
|
|
<listitem>
|
|
<para>
|
|
Tests for core-supported authentication methods,
|
|
located in <filename>src/test/authentication</filename>.
|
|
(See below for additional authentication-related tests.)
|
|
</para>
|
|
</listitem>
|
|
<listitem>
|
|
<para>
|
|
Tests stressing behavior of concurrent sessions,
|
|
located in <filename>src/test/isolation</filename>.
|
|
</para>
|
|
</listitem>
|
|
<listitem>
|
|
<para>
|
|
Tests for crash recovery and physical replication,
|
|
located in <filename>src/test/recovery</filename>.
|
|
</para>
|
|
</listitem>
|
|
<listitem>
|
|
<para>
|
|
Tests for logical replication,
|
|
located in <filename>src/test/subscription</filename>.
|
|
</para>
|
|
</listitem>
|
|
<listitem>
|
|
<para>
|
|
Tests of client programs, located under <filename>src/bin</filename>.
|
|
</para>
|
|
</listitem>
|
|
</itemizedlist>
|
|
|
|
<para>
|
|
When using <literal>installcheck</literal> mode, these tests will create
|
|
and destroy test databases whose names
|
|
include <literal>regression</literal>, for
|
|
example <literal>pl_regression</literal>
|
|
or <literal>contrib_regression</literal>. Beware of
|
|
using <literal>installcheck</literal> mode with an installation that has
|
|
any non-test databases named that way.
|
|
</para>
|
|
|
|
<para>
|
|
Some of these auxiliary test suites use the TAP infrastructure explained
|
|
in <xref linkend="regress-tap"/>.
|
|
The TAP-based tests are run only when PostgreSQL was configured with the
|
|
option <option>--enable-tap-tests</option>. This is recommended for
|
|
development, but can be omitted if there is no suitable Perl installation.
|
|
</para>
|
|
|
|
<para>
|
|
Some test suites are not run by default, either because they are not secure
|
|
to run on a multiuser system or because they require special software. You
|
|
can decide which test suites to run additionally by setting the
|
|
<command>make</command> or environment variable
|
|
<varname>PG_TEST_EXTRA</varname> to a whitespace-separated list, for
|
|
example:
|
|
<programlisting>
|
|
make check-world PG_TEST_EXTRA='kerberos ldap ssl'
|
|
</programlisting>
|
|
The following values are currently supported:
|
|
<variablelist>
|
|
<varlistentry>
|
|
<term><literal>kerberos</literal></term>
|
|
<listitem>
|
|
<para>
|
|
Runs the test suite under <filename>src/test/kerberos</filename>. This
|
|
requires an MIT Kerberos installation and opens TCP/IP listen sockets.
|
|
</para>
|
|
</listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><literal>ldap</literal></term>
|
|
<listitem>
|
|
<para>
|
|
Runs the test suite under <filename>src/test/ldap</filename>. This
|
|
requires an <productname>OpenLDAP</productname> installation and opens
|
|
TCP/IP listen sockets.
|
|
</para>
|
|
</listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><literal>ssl</literal></term>
|
|
<listitem>
|
|
<para>
|
|
Runs the test suite under <filename>src/test/ssl</filename>. This opens TCP/IP listen sockets.
|
|
</para>
|
|
</listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><literal>wal_consistency_checking</literal></term>
|
|
<listitem>
|
|
<para>
|
|
Uses <literal>wal_consistency_checking=all</literal> while running
|
|
certain tests under <filename>src/test/recovery</filename>. Not
|
|
enabled by default because it is resource intensive.
|
|
</para>
|
|
</listitem>
|
|
</varlistentry>
|
|
</variablelist>
|
|
|
|
Tests for features that are not supported by the current build
|
|
configuration are not run even if they are mentioned in
|
|
<varname>PG_TEST_EXTRA</varname>.
|
|
</para>
|
|
|
|
<para>
|
|
In addition, there are tests in <filename>src/test/modules</filename>
|
|
which will be run by <literal>make check-world</literal> but not
|
|
by <literal>make installcheck-world</literal>. This is because they
|
|
install non-production extensions or have other side-effects that are
|
|
considered undesirable for a production installation. You can
|
|
use <literal>make install</literal> and <literal>make
|
|
installcheck</literal> in one of those subdirectories if you wish,
|
|
but it's not recommended to do so with a non-test server.
|
|
</para>
|
|
</sect2>
|
|
|
|
<sect2 id="regress-run-locale">
|
|
<title>Locale and Encoding</title>
|
|
|
|
<para>
|
|
By default, tests using a temporary installation use the
|
|
locale defined in the current environment and the corresponding
|
|
database encoding as determined by <command>initdb</command>. It
|
|
can be useful to test different locales by setting the appropriate
|
|
environment variables, for example:
|
|
<screen>
|
|
make check LANG=C
|
|
make check LC_COLLATE=en_US.utf8 LC_CTYPE=fr_CA.utf8
|
|
</screen>
|
|
For implementation reasons, setting <envar>LC_ALL</envar> does not
|
|
work for this purpose; all the other locale-related environment
|
|
variables do work.
|
|
</para>
|
|
|
|
<para>
|
|
When testing against an existing installation, the locale is
|
|
determined by the existing database cluster and cannot be set
|
|
separately for the test run.
|
|
</para>
|
|
|
|
<para>
|
|
You can also choose the database encoding explicitly by setting
|
|
the variable <envar>ENCODING</envar>, for example:
|
|
<screen>
|
|
make check LANG=C ENCODING=EUC_JP
|
|
</screen>
|
|
Setting the database encoding this way typically only makes sense
|
|
if the locale is C; otherwise the encoding is chosen automatically
|
|
from the locale, and specifying an encoding that does not match
|
|
the locale will result in an error.
|
|
</para>
|
|
|
|
<para>
|
|
The database encoding can be set for tests against either a temporary or
|
|
an existing installation, though in the latter case it must be
|
|
compatible with the installation's locale.
|
|
</para>
|
|
</sect2>
|
|
|
|
<sect2 id="regress-run-custom-settings">
|
|
<title>Custom Server Settings</title>
|
|
|
|
<para>
|
|
Custom server settings to use when running a regression test suite can be
|
|
set in the <varname>PGOPTIONS</varname> environment variable (for settings
|
|
that allow this):
|
|
<screen>
|
|
make check PGOPTIONS="-c force_parallel_mode=regress -c work_mem=50MB"
|
|
</screen>
|
|
When running against a temporary installation, custom settings can also be
|
|
set by supplying a pre-written <filename>postgresql.conf</filename>:
|
|
<screen>
|
|
echo 'log_checkpoints = on' > test_postgresql.conf
|
|
echo 'work_mem = 50MB' >> test_postgresql.conf
|
|
make check EXTRA_REGRESS_OPTS="--temp-config=test_postgresql.conf"
|
|
</screen>
|
|
</para>
|
|
|
|
<para>
|
|
This can be useful to enable additional logging, adjust resource limits,
|
|
or enable extra run-time checks such as <xref
|
|
linkend="guc-debug-discard-caches"/>.
|
|
</para>
|
|
</sect2>
|
|
|
|
<sect2 id="regress-run-extra-tests">
|
|
<title>Extra Tests</title>
|
|
|
|
<para>
|
|
The core regression test suite contains a few test files that are not
|
|
run by default, because they might be platform-dependent or take a
|
|
very long time to run. You can run these or other extra test
|
|
files by setting the variable <envar>EXTRA_TESTS</envar>. For
|
|
example, to run the <literal>numeric_big</literal> test:
|
|
<screen>
|
|
make check EXTRA_TESTS=numeric_big
|
|
</screen>
|
|
</para>
|
|
</sect2>
|
|
</sect1>
|
|
|
|
<sect1 id="regress-evaluation">
|
|
<title>Test Evaluation</title>
|
|
|
|
<para>
|
|
Some properly installed and fully functional
|
|
<productname>PostgreSQL</productname> installations can
|
|
<quote>fail</quote> some of these regression tests due to
|
|
platform-specific artifacts such as varying floating-point representation
|
|
and message wording. The tests are currently evaluated using a simple
|
|
<command>diff</command> comparison against the outputs
|
|
generated on a reference system, so the results are sensitive to
|
|
small system differences. When a test is reported as
|
|
<quote>failed</quote>, always examine the differences between
|
|
expected and actual results; you might find that the
|
|
differences are not significant. Nonetheless, we still strive to
|
|
maintain accurate reference files across all supported platforms,
|
|
so it can be expected that all tests pass.
|
|
</para>
|
|
|
|
<para>
|
|
The actual outputs of the regression tests are in files in the
|
|
<filename>src/test/regress/results</filename> directory. The test
|
|
script uses <command>diff</command> to compare each output
|
|
file against the reference outputs stored in the
|
|
<filename>src/test/regress/expected</filename> directory. Any
|
|
differences are saved for your inspection in
|
|
<filename>src/test/regress/regression.diffs</filename>.
|
|
(When running a test suite other than the core tests, these files
|
|
of course appear in the relevant subdirectory,
|
|
not <filename>src/test/regress</filename>.)
|
|
</para>
|
|
|
|
<para>
|
|
If you don't
|
|
like the <command>diff</command> options that are used by default, set the
|
|
environment variable <envar>PG_REGRESS_DIFF_OPTS</envar>, for
|
|
instance <literal>PG_REGRESS_DIFF_OPTS='-c'</literal>. (Or you
|
|
can run <command>diff</command> yourself, if you prefer.)
|
|
</para>
|
|
|
|
<para>
|
|
If for some reason a particular platform generates a <quote>failure</quote>
|
|
for a given test, but inspection of the output convinces you that
|
|
the result is valid, you can add a new comparison file to silence
|
|
the failure report in future test runs. See
|
|
<xref linkend="regress-variant"/> for details.
|
|
</para>
|
|
|
|
<sect2 id="regress-evaluation-message-differences">
|
|
<title>Error Message Differences</title>
|
|
|
|
<para>
|
|
Some of the regression tests involve intentional invalid input
|
|
values. Error messages can come from either the
|
|
<productname>PostgreSQL</productname> code or from the host
|
|
platform system routines. In the latter case, the messages can
|
|
vary between platforms, but should reflect similar
|
|
information. These differences in messages will result in a
|
|
<quote>failed</quote> regression test that can be validated by
|
|
inspection.
|
|
</para>
|
|
</sect2>
|
|
|
|
<sect2 id="regress-evaluation-locale-differences">
|
|
<title>Locale Differences</title>
|
|
|
|
<para>
|
|
If you run the tests against a server that was
|
|
initialized with a collation-order locale other than C, then
|
|
there might be differences due to sort order and subsequent
|
|
failures. The regression test suite is set up to handle this
|
|
problem by providing alternate result files that together are
|
|
known to handle a large number of locales.
|
|
</para>
|
|
|
|
<para>
|
|
To run the tests in a different locale when using the
|
|
temporary-installation method, pass the appropriate
|
|
locale-related environment variables on
|
|
the <command>make</command> command line, for example:
|
|
<programlisting>
|
|
make check LANG=de_DE.utf8
|
|
</programlisting>
|
|
(The regression test driver unsets <envar>LC_ALL</envar>, so it
|
|
does not work to choose the locale using that variable.) To use
|
|
no locale, either unset all locale-related environment variables
|
|
(or set them to <literal>C</literal>) or use the following
|
|
special invocation:
|
|
<programlisting>
|
|
make check NO_LOCALE=1
|
|
</programlisting>
|
|
When running the tests against an existing installation, the
|
|
locale setup is determined by the existing installation. To
|
|
change it, initialize the database cluster with a different
|
|
locale by passing the appropriate options
|
|
to <command>initdb</command>.
|
|
</para>
|
|
|
|
<para>
|
|
In general, it is advisable to try to run the
|
|
regression tests in the locale setup that is wanted for
|
|
production use, as this will exercise the locale- and
|
|
encoding-related code portions that will actually be used in
|
|
production. Depending on the operating system environment, you
|
|
might get failures, but then you will at least know what
|
|
locale-specific behaviors to expect when running real
|
|
applications.
|
|
</para>
|
|
</sect2>
|
|
|
|
<sect2 id="regress-evaluation-date-time-differences">
|
|
<title>Date and Time Differences</title>
|
|
|
|
<para>
|
|
Most of the date and time results are dependent on the time zone
|
|
environment. The reference files are generated for time zone
|
|
<literal>PST8PDT</literal> (Berkeley, California), and there will be
|
|
apparent failures if the tests are not run with that time zone setting.
|
|
The regression test driver sets environment variable
|
|
<envar>PGTZ</envar> to <literal>PST8PDT</literal>, which normally
|
|
ensures proper results.
|
|
</para>
|
|
</sect2>
|
|
|
|
<sect2 id="regress-evaluation-float-differences">
|
|
<title>Floating-Point Differences</title>
|
|
|
|
<para>
|
|
Some of the tests involve computing 64-bit floating-point numbers (<type>double
|
|
precision</type>) from table columns. Differences in
|
|
results involving mathematical functions of <type>double
|
|
precision</type> columns have been observed. The <literal>float8</literal> and
|
|
<literal>geometry</literal> tests are particularly prone to small differences
|
|
across platforms, or even with different compiler optimization settings.
|
|
Human eyeball comparison is needed to determine the real
|
|
significance of these differences which are usually 10 places to
|
|
the right of the decimal point.
|
|
</para>
|
|
|
|
<para>
|
|
Some systems display minus zero as <literal>-0</literal>, while others
|
|
just show <literal>0</literal>.
|
|
</para>
|
|
|
|
<para>
|
|
Some systems signal errors from <function>pow()</function> and
|
|
<function>exp()</function> differently from the mechanism
|
|
expected by the current <productname>PostgreSQL</productname>
|
|
code.
|
|
</para>
|
|
</sect2>
|
|
|
|
<sect2 id="regress-evaluation-ordering-differences">
|
|
<title>Row Ordering Differences</title>
|
|
|
|
<para>
|
|
You might see differences in which the same rows are output in a
|
|
different order than what appears in the expected file. In most cases
|
|
this is not, strictly speaking, a bug. Most of the regression test
|
|
scripts are not so pedantic as to use an <literal>ORDER BY</literal> for every single
|
|
<literal>SELECT</literal>, and so their result row orderings are not well-defined
|
|
according to the SQL specification. In practice, since we are
|
|
looking at the same queries being executed on the same data by the same
|
|
software, we usually get the same result ordering on all platforms,
|
|
so the lack of <literal>ORDER BY</literal> is not a problem. Some queries do exhibit
|
|
cross-platform ordering differences, however. When testing against an
|
|
already-installed server, ordering differences can also be caused by
|
|
non-C locale settings or non-default parameter settings, such as custom values
|
|
of <varname>work_mem</varname> or the planner cost parameters.
|
|
</para>
|
|
|
|
<para>
|
|
Therefore, if you see an ordering difference, it's not something to
|
|
worry about, unless the query does have an <literal>ORDER BY</literal> that your
|
|
result is violating. However, please report it anyway, so that we can add an
|
|
<literal>ORDER BY</literal> to that particular query to eliminate the bogus
|
|
<quote>failure</quote> in future releases.
|
|
</para>
|
|
|
|
<para>
|
|
You might wonder why we don't order all the regression test queries explicitly
|
|
to get rid of this issue once and for all. The reason is that that would
|
|
make the regression tests less useful, not more, since they'd tend
|
|
to exercise query plan types that produce ordered results to the
|
|
exclusion of those that don't.
|
|
</para>
|
|
</sect2>
|
|
|
|
<sect2 id="regress-evaluation-stack-depth">
|
|
<title>Insufficient Stack Depth</title>
|
|
|
|
<para>
|
|
If the <literal>errors</literal> test results in a server crash
|
|
at the <literal>select infinite_recurse()</literal> command, it means that
|
|
the platform's limit on process stack size is smaller than the
|
|
<xref linkend="guc-max-stack-depth"/> parameter indicates. This
|
|
can be fixed by running the server under a higher stack
|
|
size limit (4MB is recommended with the default value of
|
|
<varname>max_stack_depth</varname>). If you are unable to do that, an
|
|
alternative is to reduce the value of <varname>max_stack_depth</varname>.
|
|
</para>
|
|
|
|
<para>
|
|
On platforms supporting <function>getrlimit()</function>, the server should
|
|
automatically choose a safe value of <varname>max_stack_depth</varname>;
|
|
so unless you've manually overridden this setting, a failure of this
|
|
kind is a reportable bug.
|
|
</para>
|
|
</sect2>
|
|
|
|
<sect2 id="regress-evaluation-random-test">
|
|
<title>The <quote>random</quote> Test</title>
|
|
|
|
<para>
|
|
The <literal>random</literal> test script is intended to produce
|
|
random results. In very rare cases, this causes that regression
|
|
test to fail. Typing:
|
|
<programlisting>
|
|
diff results/random.out expected/random.out
|
|
</programlisting>
|
|
should produce only one or a few lines of differences. You need
|
|
not worry unless the random test fails repeatedly.
|
|
</para>
|
|
</sect2>
|
|
|
|
<sect2 id="regress-evaluation-config-params">
|
|
<title>Configuration Parameters</title>
|
|
|
|
<para>
|
|
When running the tests against an existing installation, some non-default
|
|
parameter settings could cause the tests to fail. For example, changing
|
|
parameters such as <varname>enable_seqscan</varname> or
|
|
<varname>enable_indexscan</varname> could cause plan changes that would
|
|
affect the results of tests that use <command>EXPLAIN</command>.
|
|
</para>
|
|
</sect2>
|
|
</sect1>
|
|
|
|
<!-- We might want to move the following section into the developer's guide. -->
|
|
<sect1 id="regress-variant">
|
|
<title>Variant Comparison Files</title>
|
|
|
|
<para>
|
|
Since some of the tests inherently produce environment-dependent
|
|
results, we have provided ways to specify alternate <quote>expected</quote>
|
|
result files. Each regression test can have several comparison files
|
|
showing possible results on different platforms. There are two
|
|
independent mechanisms for determining which comparison file is used
|
|
for each test.
|
|
</para>
|
|
|
|
<para>
|
|
The first mechanism allows comparison files to be selected for
|
|
specific platforms. There is a mapping file,
|
|
<filename>src/test/regress/resultmap</filename>, that defines
|
|
which comparison file to use for each platform.
|
|
To eliminate bogus test <quote>failures</quote> for a particular platform,
|
|
you first choose or make a variant result file, and then add a line to the
|
|
<filename>resultmap</filename> file.
|
|
</para>
|
|
|
|
<para>
|
|
Each line in the mapping file is of the form
|
|
<synopsis>
|
|
testname:output:platformpattern=comparisonfilename
|
|
</synopsis>
|
|
The test name is just the name of the particular regression test
|
|
module. The output value indicates which output file to check. For the
|
|
standard regression tests, this is always <literal>out</literal>. The
|
|
value corresponds to the file extension of the output file.
|
|
The platform pattern is a pattern in the style of the Unix
|
|
tool <command>expr</command> (that is, a regular expression with an implicit
|
|
<literal>^</literal> anchor at the start). It is matched against the
|
|
platform name as printed by <command>config.guess</command>.
|
|
The comparison file name is the base name of the substitute result
|
|
comparison file.
|
|
</para>
|
|
|
|
<para>
|
|
For example: some systems lack a working <literal>strtof</literal> function,
|
|
for which our workaround causes rounding errors in the
|
|
<filename>float4</filename> regression test.
|
|
Therefore, we provide a variant comparison file,
|
|
<filename>float4-misrounded-input.out</filename>, which includes
|
|
the results to be expected on these systems. To silence the bogus
|
|
<quote>failure</quote> message on <systemitem>Cygwin</systemitem>
|
|
platforms, <filename>resultmap</filename> includes:
|
|
<programlisting>
|
|
float4:out:.*-.*-cygwin.*=float4-misrounded-input.out
|
|
</programlisting>
|
|
which will trigger on any machine where the output of
|
|
<command>config.guess</command> matches <literal>.*-.*-cygwin.*</literal>.
|
|
Other lines in <filename>resultmap</filename> select the variant comparison
|
|
file for other platforms where it's appropriate.
|
|
</para>
|
|
|
|
<para>
|
|
The second selection mechanism for variant comparison files is
|
|
much more automatic: it simply uses the <quote>best match</quote> among
|
|
several supplied comparison files. The regression test driver
|
|
script considers both the standard comparison file for a test,
|
|
<literal><replaceable>testname</replaceable>.out</literal>, and variant files named
|
|
<literal><replaceable>testname</replaceable>_<replaceable>digit</replaceable>.out</literal>
|
|
(where the <replaceable>digit</replaceable> is any single digit
|
|
<literal>0</literal>-<literal>9</literal>). If any such file is an exact match,
|
|
the test is considered to pass; otherwise, the one that generates
|
|
the shortest diff is used to create the failure report. (If
|
|
<filename>resultmap</filename> includes an entry for the particular
|
|
test, then the base <replaceable>testname</replaceable> is the substitute
|
|
name given in <filename>resultmap</filename>.)
|
|
</para>
|
|
|
|
<para>
|
|
For example, for the <literal>char</literal> test, the comparison file
|
|
<filename>char.out</filename> contains results that are expected
|
|
in the <literal>C</literal> and <literal>POSIX</literal> locales, while
|
|
the file <filename>char_1.out</filename> contains results sorted as
|
|
they appear in many other locales.
|
|
</para>
|
|
|
|
<para>
|
|
The best-match mechanism was devised to cope with locale-dependent
|
|
results, but it can be used in any situation where the test results
|
|
cannot be predicted easily from the platform name alone. A limitation of
|
|
this mechanism is that the test driver cannot tell which variant is
|
|
actually <quote>correct</quote> for the current environment; it will just pick
|
|
the variant that seems to work best. Therefore it is safest to use this
|
|
mechanism only for variant results that you are willing to consider
|
|
equally valid in all contexts.
|
|
</para>
|
|
|
|
</sect1>
|
|
|
|
<sect1 id="regress-tap">
|
|
<title>TAP Tests</title>
|
|
|
|
<para>
|
|
Various tests, particularly the client program tests
|
|
under <filename>src/bin</filename>, use the Perl TAP tools and are run
|
|
using the Perl testing program <command>prove</command>. You can pass
|
|
command-line options to <command>prove</command> by setting
|
|
the <command>make</command> variable <varname>PROVE_FLAGS</varname>, for example:
|
|
<programlisting>
|
|
make -C src/bin check PROVE_FLAGS='--timer'
|
|
</programlisting>
|
|
See the manual page of <command>prove</command> for more information.
|
|
</para>
|
|
|
|
<para>
|
|
The <command>make</command> variable <varname>PROVE_TESTS</varname>
|
|
can be used to define a whitespace-separated list of paths relative
|
|
to the <filename>Makefile</filename> invoking <command>prove</command>
|
|
to run the specified subset of tests instead of the default
|
|
<filename>t/*.pl</filename>. For example:
|
|
<programlisting>
|
|
make check PROVE_TESTS='t/001_test1.pl t/003_test3.pl'
|
|
</programlisting>
|
|
</para>
|
|
|
|
<para>
|
|
The TAP tests require the Perl module <literal>IPC::Run</literal>.
|
|
This module is available from
|
|
<ulink url="https://metacpan.org/dist/IPC-Run">CPAN</ulink>
|
|
or an operating system package.
|
|
They also require <productname>PostgreSQL</productname> to be
|
|
configured with the option <option>--enable-tap-tests</option>.
|
|
</para>
|
|
|
|
<para>
|
|
Generically speaking, the TAP tests will test the executables in a
|
|
previously-installed installation tree if you say <literal>make
|
|
installcheck</literal>, or will build a new local installation tree from
|
|
current sources if you say <literal>make check</literal>. In either
|
|
case they will initialize a local instance (data directory) and
|
|
transiently run a server in it. Some of these tests run more than one
|
|
server. Thus, these tests can be fairly resource-intensive.
|
|
</para>
|
|
|
|
<para>
|
|
It's important to realize that the TAP tests will start test server(s)
|
|
even when you say <literal>make installcheck</literal>; this is unlike
|
|
the traditional non-TAP testing infrastructure, which expects to use an
|
|
already-running test server in that case. Some PostgreSQL
|
|
subdirectories contain both traditional-style and TAP-style tests,
|
|
meaning that <literal>make installcheck</literal> will produce a mix of
|
|
results from temporary servers and the already-running test server.
|
|
</para>
|
|
|
|
<sect2 id="regress-tap-vars">
|
|
<title>Environment variables</title>
|
|
|
|
<para>
|
|
Data directories are named according to the test filename, and will be
|
|
retained if a test fails. If the environment variable
|
|
<varname>PG_TEST_NOCLEAN</varname> is set, data directories will be
|
|
retained regardless of test status. For example, retaining the data
|
|
directory regardless of test results when running the
|
|
<application>pg_dump</application> tests:
|
|
<programlisting>
|
|
PG_TEST_NOCLEAN=1 make -C src/bin/pg_dump check
|
|
</programlisting>
|
|
</para>
|
|
|
|
<para>
|
|
Many operations in the test suites use a 180-second timeout, which on slow
|
|
hosts may lead to load-induced timeouts. Setting the environment variable
|
|
<varname>PG_TEST_TIMEOUT_DEFAULT</varname> to a higher number will change
|
|
the default to avoid this.
|
|
</para>
|
|
</sect2>
|
|
|
|
</sect1>
|
|
|
|
<sect1 id="regress-coverage">
|
|
<title>Test Coverage Examination</title>
|
|
|
|
<para>
|
|
The PostgreSQL source code can be compiled with coverage testing
|
|
instrumentation, so that it becomes possible to examine which
|
|
parts of the code are covered by the regression tests or any other
|
|
test suite that is run with the code. This is currently supported
|
|
when compiling with GCC, and it requires the <command>gcov</command>
|
|
and <command>lcov</command> programs.
|
|
</para>
|
|
|
|
<para>
|
|
A typical workflow looks like this:
|
|
<screen>
|
|
./configure --enable-coverage ... OTHER OPTIONS ...
|
|
make
|
|
make check # or other test suite
|
|
make coverage-html
|
|
</screen>
|
|
Then point your HTML browser
|
|
to <filename>coverage/index.html</filename>.
|
|
</para>
|
|
|
|
<para>
|
|
If you don't have <command>lcov</command> or prefer text output over an
|
|
HTML report, you can run
|
|
<screen>
|
|
make coverage
|
|
</screen>
|
|
instead of <literal>make coverage-html</literal>, which will
|
|
produce <filename>.gcov</filename> output files for each source file
|
|
relevant to the test. (<literal>make coverage</literal> and <literal>make
|
|
coverage-html</literal> will overwrite each other's files, so mixing them
|
|
might be confusing.)
|
|
</para>
|
|
|
|
<para>
|
|
You can run several different tests before making the coverage report;
|
|
the execution counts will accumulate. If you want
|
|
to reset the execution counts between test runs, run:
|
|
<screen>
|
|
make coverage-clean
|
|
</screen>
|
|
</para>
|
|
|
|
<para>
|
|
You can run the <literal>make coverage-html</literal> or <literal>make
|
|
coverage</literal> command in a subdirectory if you want a coverage
|
|
report for only a portion of the code tree.
|
|
</para>
|
|
|
|
<para>
|
|
Use <literal>make distclean</literal> to clean up when done.
|
|
</para>
|
|
</sect1>
|
|
|
|
</chapter>
|