From nobody Fri May 3 12:48:50 2024 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 1500631510033275.58710191188663; Fri, 21 Jul 2017 03:05:10 -0700 (PDT) Received: from localhost ([::1]:41953 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dYUNY-0004Uk-KL for importer@patchew.org; Fri, 21 Jul 2017 05:37:48 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:49753) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dYUKj-0002Ut-Tb for qemu-devel@nongnu.org; Fri, 21 Jul 2017 05:34:55 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dYUKi-0008Et-Pm for qemu-devel@nongnu.org; Fri, 21 Jul 2017 05:34:53 -0400 Received: from mx1.redhat.com ([209.132.183.28]:34608) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dYUKf-00088j-HZ; Fri, 21 Jul 2017 05:34:49 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 2A74A4A54D; Fri, 21 Jul 2017 09:34:30 +0000 (UTC) Received: from localhost (ovpn-117-219.ams2.redhat.com [10.36.117.219]) by smtp.corp.redhat.com (Postfix) with ESMTP id 09816841F1; Fri, 21 Jul 2017 09:34:17 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 2A74A4A54D Authentication-Results: ext-mx02.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx02.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=stefanha@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com 2A74A4A54D From: Stefan Hajnoczi To: Date: Fri, 21 Jul 2017 10:34:16 +0100 Message-Id: <20170721093416.17816-1-stefanha@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.26]); Fri, 21 Jul 2017 09:34:35 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH] qemu-iotests: add a "how to" to ./README X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Kevin Wolf , Ishani Chugh , Stefan Hajnoczi , qemu-block@nongnu.org Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RSF_0 Z_629925259 SPT_0 Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" There is not much getting started documentation for qemu-iotests. This patch explains how to create a new test and covers the overall testing approach. Cc: Ishani Chugh Signed-off-by: Stefan Hajnoczi Reviewed-by: Eric Blake Reviewed-by: Manos Pitsidianakis Reviewed-by: Philippe Mathieu-Daud=C3=A9 --- tests/qemu-iotests/README | 83 +++++++++++++++++++++++++++++++++++++++++++= ++++ 1 file changed, 83 insertions(+) diff --git a/tests/qemu-iotests/README b/tests/qemu-iotests/README index 6079b40..8259b9f 100644 --- a/tests/qemu-iotests/README +++ b/tests/qemu-iotests/README @@ -14,8 +14,91 @@ Just run ./check to run all tests for the raw image form= at, or ./check -qcow2 to test the qcow2 image format. The output of ./check -h explains additional options to test further image formats or I/O methods. =20 +* Testing approach + +Each test is an executable file (usually a bash script) that is run by the +./check test harness. Standard out and standard error are captured to an +output file. If the output file differs from the "golden master" output f= ile +for the test then it fails. + +Tests are simply a sequence of commands that produce output and the test i= tself +does not judge whether it passed or failed. If you find yourself writing +checks to determine success or failure then you should rethink the test and +rely on output diffing instead. + +** Filtering volatile output + +When output contains absolute file paths, timestamps, process IDs, hostnam= es, +or other volatile strings, the diff against golden master output will fail. +Such output must be filtered to replace volatile strings with fixed +placeholders. + +For example, the path to the temporary working directory changes between t= est +runs so it must be filtered: + + sed -e "s#$TEST_DIR/#TEST_DIR/#g" + +Commonly needed filters are available in ./common.filter. + +** Python tests + +Most tests are implemented in bash but it is difficult to interact with th= e QMP +monitor. A Python module called 'iotests' is available for tests that req= uire +JSON and interacting with QEMU. + +* How to create a test + +1. Choose an unused test number + +Tests are identified by a unique number. Look for the highest test case n= umber +by looking at the test files. Then search the qemu-devel@nongnu.org maili= ng +list to check if anyone has already sent patches using the next available +number. You may need to increment the number a few times to reach an unus= ed +number. + +2. Create the test file + +Copy an existing test (one that most closely resembles what you wish to te= st) +to the new test number: + + cp 001 + +3. Assign groups to the test + +Add your test to the ./group file. This file is the index of tests and as= signs +them to functional groups like "rw" for read-write tests. Most tests belo= ng to +the "rw" and "auto" groups. "auto" means the test runs when ./check is in= voked +without a -g argument. + +Consider adding your test to the "quick" group if it executes quickly (<1s= ). +This group is run by "make check-block" and is often included as part of b= uild +tests in continuous integration systems. + +4. Write the test + +Edit the test script. Look at existing tests for examples. + +5. Generate the golden master file + +Run your test with "./check ". You may need to pass addition= al +options to use an image format or protocol. + +The test will fail because there is no golden master yet. Inspect the out= put +that your test generated with "cat .out.bad". + +Verify that the output is as expected and contains no volatile strings like +timestamps. You may need to add filters to your test to remove volatile +strings. + +Once you are happy with the test output it can be used as the golden master +with "mv .out.bad .out". Rerun the test to veri= fy +that it passes. + +Congratulations, you've created a new test! + * Feedback and patches =20 Please send improvements to the test suite, general feedback or just reports of failing tests cases to qemu-devel@nongnu.org with a CC: to qemu-block@nongnu.org. + --=20 2.9.4