summaryrefslogtreecommitdiffstats
path: root/toolkit/components/telemetry/docs/internals/tests.rst
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 19:33:14 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 19:33:14 +0000
commit36d22d82aa202bb199967e9512281e9a53db42c9 (patch)
tree105e8c98ddea1c1e4784a60a5a6410fa416be2de /toolkit/components/telemetry/docs/internals/tests.rst
parentInitial commit. (diff)
downloadfirefox-esr-36d22d82aa202bb199967e9512281e9a53db42c9.tar.xz
firefox-esr-36d22d82aa202bb199967e9512281e9a53db42c9.zip
Adding upstream version 115.7.0esr.upstream/115.7.0esr
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'toolkit/components/telemetry/docs/internals/tests.rst')
-rw-r--r--toolkit/components/telemetry/docs/internals/tests.rst99
1 files changed, 99 insertions, 0 deletions
diff --git a/toolkit/components/telemetry/docs/internals/tests.rst b/toolkit/components/telemetry/docs/internals/tests.rst
new file mode 100644
index 0000000000..58adbb94af
--- /dev/null
+++ b/toolkit/components/telemetry/docs/internals/tests.rst
@@ -0,0 +1,99 @@
+Tests
+=====
+
+A high-level test strategy for Firefox Telemetry is defined in the
+`Test Strategy document <https://docs.google.com/document/d/1Mi6va3gE4HSv5LjXNREvMa2V4q-LKIFDTwA2o4yeo_c/edit>`_.
+
+Firefox Telemetry is a complicated and old component.
+So too are the organization and expanse of its tests.
+Let’s break them down by harness.
+
+Unless otherwise mentioned the tests live in subdirectories of
+``toolkit/components/telemetry/tests``.
+
+Mochitest
+---------
+:Location: ``t/c/t/t/browser/``
+:Language: Javascript
+ (`mochitest <https://firefox-source-docs.mozilla.org/testing/mochitest-plain>`__)
+
+This test harness runs nearly the entire Firefox and gives access to multiple tabs and browser chrome APIs.
+It requires window focus to complete correctly,
+so it isn’t recommended to add new tests here.
+The tests that are here maybe would be more at home as telemetry-tests-client tests as they tend to be integration tests.
+
+Google Test
+-----------
+:Location: ``t/c/t/t/gtest/``
+:Language: C++
+ (`googletest <https://github.com/google/googletest>`_)
+
+This test harness runs a specially-built gtest shell around libxul which allows you to write unit tests against public C++ APIs.
+It should be used to test the C++ API and core of Firefox Telemetry.
+This is for tests like
+“Do we correctly accumulate to bucket 0 if I pass -1 to ``Telemetry::Accumulate``?”
+
+Integration Tests (telemetry-tests-client and telemetry-integration-tests)
+--------------------------------------------------------------------------
+:Location: ``t/c/t/t/marionette/tests/client`` and ``t/c/t/t/integration/``
+:Language: Python
+ (`unittest <https://docs.python.org/3/library/unittest.html>`__,
+ `pytest <https://docs.pytest.org/en/latest/>`_)
+
+The most modern of the test harnesses,
+telemetry-integration-tests uses marionette to puppet the entire browser allowing us to write integration tests that include ping servers and multiple browser runs.
+You should use this if you’re testing Big Picture things like
+“Does Firefox resend its “deletion-request” ping if the network is down when Telemetry is first disabled?”.
+
+At time of writing there are two “editions” of integration tests.
+Prefer writing new tests in telemetry-tests-client
+(the unittest-based one in ``t/c/t/t/marionette/tests/client``)
+while we evaluate CI support for telemetry-integration-tests.
+
+More info: :doc:`./integration_tests/index`
+
+Definitions Files Tests
+-----------------------
+:Location: ``t/c/t/t/python``
+:Language: Python
+ (`unittest <https://docs.python.org/3/library/unittest.html>`__)
+
+This harness pulls in the parsers and scripts used to turn JSON and YAML probe definitions into code.
+It should be used to test the build scripts and formats of the definitions files
+Histograms.json, Scalars.yaml, and Events.yaml.
+This is for tests like
+“Does the build fail if someone forgot to put in a bug number for a new Histogram?”.
+
+xpcshell
+--------
+:Location: ``t/c/t/t/unit``
+:Language: Javascript
+ (`xpcshell <https://firefox-source-docs.mozilla.org/testing/xpcshell>`__)
+
+This test harness uses a stripped-down shell of the Firefox browser to run privileged Javascript.
+It should be used to write unit tests for the Javascript API and app-level logic of Firefox Telemetry.
+This is for tests like
+“Do we correctly accumulate to bucket 0 if I pass -1 to ``Telemetry.getHistogramById(...).add``?”
+and
+“Do we reschedule pings that want to be sent near local midnight?”.
+
+Since these tests are easy to write and quick to run we have in the past bent this harness in a few interesting shapes
+(see PingServer)
+to have it support integration tests as well.
+New integration tests should use telemetry-tests-client instead.
+
+Instrumentation Tests
+---------------------
+:Location: Various
+:Language: Usually Javascript
+ (`xpcshell <https://firefox-source-docs.mozilla.org/testing/xpcshell>`__ or
+ `mochitest <https://firefox-source-docs.mozilla.org/testing/mochitest-plain>`__)
+
+In addition to the tests of Firefox Telemetry,
+other code owners have written tests that ensure that their code records appropriate values to Telemetry.
+They should use the
+``toolkit/components/telemetry/tests/unit/TelemetryTestUtils.sys.mjs``
+module to make their lives easier.
+This can be used for tests like
+“If five bookmarks are read from the database,
+does the bookmark count Histogram have a value of 5 in it?”.