tests: Add test infrastructure as a Python module

Implement gem5's test infrastructure as a Python module and a run
script that can be used without scons. The new implementation has
several features that were lacking from the previous test
infrastructure such as support for multiple output formats, automatic
runtime tracking, and better support for being run in a cluster
environment.

Tests consist of one or more steps (TestUnit). Units are run in two
stages, the first a run stage and then a verify stage. Units in the
verify stage are automatically skipped if any unit run stage wasn't
run. The library currently contains TestUnit implementations that run
gem5, diff stat files, and diff output files.

Existing tests are implemented by the ClassicTest class and "just
work". New tests can that don't rely on the old "run gem5 once and
diff output" strategy can be implemented by subclassing the Test base
class or ClassicTest.

Test results can be output in multiple formats. The module currently
supports JUnit, text (short and verbose), and Python's pickle
format. JUnit output allows CI systems to automatically get more
information about test failures. The pickled output contains all state
necessary to reconstruct a tests results object and is mainly intended
for the build system and CI systems.

Since many JUnit parsers parsers assume that test suite names look
like Java package names. We currently output path-like names with
slashes separating components. Test names are translated according to
these rules:

  * '.' -> '-"
  * '/' -> '.'

The test tool, tests.py, supports the following features:

  * Test listing. Example: ./tests.py list arm/quick

  * Running tests. Example:
    ./tests.py run -o output.pickle --format pickle \
        ../build/ARM/gem5.opt \
        quick/se/00.hello/arm/linux/simple-timing

  * Displaying pickled results. Example:
    ./tests.py show --format summary *.pickle

Change-Id: I527164bd791237aacfc65e7d7c0b67b695c5d17c
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-by: Curtis Dunham <curtis.dunham@arm.com>
Reviewed-by: Joel Hestness <jthestness@gmail.com>

1 files changed, 290 insertions, 0 deletions

diff --git a/tests/testing/units.py b/tests/testing/units.py
new file mode 100644
index 000000000..6214c8f14
--- /dev/null
+++ b/tests/testing/units.py
@@ -0,0 +1,290 @@
+#!/usr/bin/env python
+#
+# Copyright (c) 2016 ARM Limited
+# All rights reserved
+#
+# The license below extends only to copyright in the software and shall
+# not be construed as granting a license to any other intellectual
+# property including but not limited to intellectual property relating
+# to a hardware implementation of the functionality of the software
+# licensed hereunder.  You may use the software subject to the license
+# terms below provided that you ensure that this notice is replicated
+# unmodified and in its entirety in all distributions of the software,
+# modified or unmodified, in source code or in binary form.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met: redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer;
+# redistributions in binary form must reproduce the above copyright
+# notice, this list of conditions and the following disclaimer in the
+# documentation and/or other materials provided with the distribution;
+# neither the name of the copyright holders nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+#
+# Authors: Andreas Sandberg
+
+from abc import ABCMeta, abstractmethod
+from datetime import datetime
+import difflib
+import functools
+import os
+import re
+import subprocess
+import sys
+import traceback
+
+from results import UnitResult
+from helpers import *
+
+_test_base = os.path.join(os.path.dirname(__file__), "..")
+
+class TestUnit(object):
+    """Base class for all test units.
+
+    A test unit is a part of a larger test case. Test cases usually
+    contain two types of units, run units (run gem5) and verify units
+    (diff output files). All unit implementations inherit from this
+    class.
+
+    A unit implementation overrides the _run() method. The test runner
+    calls the run() method, which wraps _run() to protect against
+    exceptions.
+
+    """
+
+    __metaclass__ = ABCMeta
+
+    def __init__(self, name, ref_dir, test_dir, skip=False):
+        self.name = name
+        self.ref_dir = ref_dir
+        self.test_dir = test_dir
+        self.force_skip = skip
+        self.start_time = None
+        self.stop_time = None
+
+    def result(self, state, **kwargs):
+        if self.start_time is not None and "runtime" not in kwargs:
+            self.stop_time = datetime.utcnow()
+            delta = self.stop_time - self.start_time
+            kwargs["runtime"] = delta.total_seconds()
+
+        return UnitResult(self.name, state, **kwargs)
+
+    def ok(self, **kwargs):
+        return self.result(UnitResult.STATE_OK, **kwargs)
+
+    def skip(self, **kwargs):
+        return self.result(UnitResult.STATE_SKIPPED, **kwargs)
+
+    def error(self, message, **kwargs):
+        return self.result(UnitResult.STATE_ERROR, message=message, **kwargs)
+
+    def failure(self, message, **kwargs):
+        return self.result(UnitResult.STATE_FAILURE, message=message, **kwargs)
+
+    def ref_file(self, fname):
+        return os.path.join(self.ref_dir, fname)
+
+    def out_file(self, fname):
+        return os.path.join(self.test_dir, fname)
+
+    def _read_output(self, fname, default=""):
+        try:
+            with open(self.out_file(fname), "r") as f:
+                return f.read()
+        except IOError:
+            return default
+
+    def run(self):
+        self.start_time = datetime.utcnow()
+        try:
+            if self.force_skip:
+                return self.skip()
+            else:
+                return self._run()
+        except:
+            return self.error("Python exception:\n%s" % traceback.format_exc())
+
+    @abstractmethod
+    def _run(self):
+        pass
+
+class RunGem5(TestUnit):
+    """Test unit representing a gem5 run.
+
+    Possible failure modes:
+       - gem5 failed to run -> STATE_ERROR
+       - timeout -> STATE_ERROR
+       - non-zero exit code -> STATE_ERROR
+
+    Possible non-failure results:
+       - exit code == 0 -> STATE_OK
+       - exit code == 2 -> STATE_SKIPPED
+    """
+
+    def __init__(self, gem5, gem5_args, timeout=0, **kwargs):
+        super(RunGem5, self).__init__("gem5", **kwargs)
+        self.gem5 = gem5
+        self.args = gem5_args
+        self.timeout = timeout
+
+    def _run(self):
+        gem5_cmd = [
+            self.gem5,
+            "-d", self.test_dir,
+            "-re",
+        ] + self.args
+
+        try:
+            with ProcessHelper(gem5_cmd, stdout=subprocess.PIPE,
+                               stderr=subprocess.PIPE) as p:
+                status, gem5_stdout, gem5_stderr = p.call(timeout=self.timeout)
+        except CallTimeoutException as te:
+            return self.error("Timeout", stdout=te.stdout, stderr=te.stderr)
+        except OSError as ose:
+            return self.error("Failed to launch gem5: %s" % ose)
+
+        stderr = "\n".join([
+            "*** gem5 stderr ***",
+            gem5_stderr,
+            "",
+            "*** m5out/simerr ***",
+            self._read_output("simerr"),
+        ])
+
+        stdout = "\n".join([
+            "*** gem5 stdout ***",
+            gem5_stdout,
+            "",
+            "*** m5out/simout ***",
+            self._read_output("simout"),
+        ])
+
+        # Signal
+        if status < 0:
+            return self.error("gem5 terminated by signal %i" % (-status, ),
+                              stdout=stdout, stderr=stderr)
+        elif status == 2:
+            return self.skip(stdout=stdout, stderr=stderr)
+        elif status > 0:
+            return self.error("gem5 exited with non-zero status: %i" % status,
+                              stdout=stdout, stderr=stderr)
+        else:
+            return self.ok(stdout=stdout, stderr=stderr)
+
+class DiffOutFile(TestUnit):
+    """Test unit comparing and output file and a reference file."""
+
+    # regular expressions of lines to ignore when diffing outputs
+    diff_ignore_regexes = {
+        "simout" : [
+            re.compile('^Redirecting (stdout|stderr) to'),
+            re.compile('^gem5 compiled '),
+            re.compile('^gem5 started '),
+            re.compile('^gem5 executing on '),
+            re.compile('^command line:'),
+            re.compile("^Couldn't import dot_parser,"),
+            re.compile("^info: kernel located at:"),
+            re.compile("^Couldn't unlink "),
+            re.compile("^Using GPU kernel code file\(s\) "),
+        ],
+        "simerr" : [
+            #re.compile('^Simulation complete at'),
+        ],
+        "config.ini" : [
+            re.compile("^(executable|readfile|kernel|image_file)="),
+            re.compile("^(cwd|input|codefile)="),
+        ],
+        "config.json" : [
+            re.compile(r'''^\s*"(executable|readfile|kernel|image_file)":'''),
+            re.compile(r'''^\s*"(cwd|input|codefile)":'''),
+        ],
+    }
+
+    def __init__(self, fname, **kwargs):
+        super(DiffOutFile, self).__init__("diff[%s]" % fname,
+                                          **kwargs)
+
+        self.fname = fname
+        self.line_filters = DiffOutFile.diff_ignore_regexes.get(fname, tuple())
+
+    def _filter_file(self, fname):
+        def match_line(l):
+            for r in self.line_filters:
+                if r.match(l):
+                    return True
+            return False
+
+        with open(fname, "r") as f:
+            for l in f:
+                if not match_line(l):
+                    yield l
+
+
+    def _run(self):
+        fname = self.fname
+        ref = self.ref_file(fname)
+        out = self.out_file(fname)
+
+        if not os.path.exists(ref):
+            return self.error("%s doesn't exist in reference directory" \
+                              % fname)
+
+        if not os.path.exists(out):
+            return self.error("%s doesn't exist in output directory" % fname)
+
+        diff = difflib.unified_diff(
+            tuple(self._filter_file(ref)),
+            tuple(self._filter_file(out)),
+            fromfile="ref/%s" % fname, tofile="out/%s" % fname)
+
+        diff = list(diff)
+        if diff:
+            return self.error("ref/%s and out/%s differ" % (fname, fname),
+                              stderr="".join(diff))
+        else:
+            return self.ok(stdout="-- ref/%s and out/%s are identical --" \
+                           % (fname, fname))
+
+class DiffStatFile(TestUnit):
+    """Test unit comparing two gem5 stat files."""
+
+    def __init__(self, **kwargs):
+        super(DiffStatFile, self).__init__("stat_diff", **kwargs)
+
+        self.stat_diff = os.path.join(_test_base, "diff-out")
+
+    def _run(self):
+        stats = "stats.txt"
+
+        cmd = [
+            self.stat_diff,
+            self.ref_file(stats), self.out_file(stats),
+        ]
+        with ProcessHelper(cmd,
+                           stdout=subprocess.PIPE,
+                           stderr=subprocess.PIPE) as p:
+            status, stdout, stderr = p.call()
+
+        if status == 0:
+            return self.ok(stdout=stdout, stderr=stderr)
+        if status == 1:
+            return self.failure("Statistics mismatch",
+                                stdout=stdout, stderr=stderr)
+        else:
+            return self.error("diff-out returned an error: %i" % status,
+                              stdout=stdout, stderr=stderr)