| # Licensed under the Apache License: http://www.apache.org/licenses/LICENSE-2.0 |
| # For details: https://github.com/nedbat/coveragepy/blob/master/NOTICE.txt |
| |
| """Raw data collector for coverage.py.""" |
| |
| import os |
| import sys |
| |
| from coverage import env |
| from coverage.backward import litems, range # pylint: disable=redefined-builtin |
| from coverage.debug import short_stack |
| from coverage.disposition import FileDisposition |
| from coverage.misc import CoverageException, isolate_module |
| from coverage.pytracer import PyTracer |
| |
| os = isolate_module(os) |
| |
| |
| try: |
| # Use the C extension code when we can, for speed. |
| from coverage.tracer import CTracer, CFileDisposition |
| except ImportError: |
| # Couldn't import the C extension, maybe it isn't built. |
| if os.getenv('COVERAGE_TEST_TRACER') == 'c': |
| # During testing, we use the COVERAGE_TEST_TRACER environment variable |
| # to indicate that we've fiddled with the environment to test this |
| # fallback code. If we thought we had a C tracer, but couldn't import |
| # it, then exit quickly and clearly instead of dribbling confusing |
| # errors. I'm using sys.exit here instead of an exception because an |
| # exception here causes all sorts of other noise in unittest. |
| sys.stderr.write("*** COVERAGE_TEST_TRACER is 'c' but can't import CTracer!\n") |
| sys.exit(1) |
| CTracer = None |
| |
| |
| class Collector(object): |
| """Collects trace data. |
| |
| Creates a Tracer object for each thread, since they track stack |
| information. Each Tracer points to the same shared data, contributing |
| traced data points. |
| |
| When the Collector is started, it creates a Tracer for the current thread, |
| and installs a function to create Tracers for each new thread started. |
| When the Collector is stopped, all active Tracers are stopped. |
| |
| Threads started while the Collector is stopped will never have Tracers |
| associated with them. |
| |
| """ |
| |
| # The stack of active Collectors. Collectors are added here when started, |
| # and popped when stopped. Collectors on the stack are paused when not |
| # the top, and resumed when they become the top again. |
| _collectors = [] |
| |
| # The concurrency settings we support here. |
| SUPPORTED_CONCURRENCIES = {"greenlet", "eventlet", "gevent", "thread"} |
| |
| def __init__( |
| self, should_trace, check_include, should_start_context, file_mapper, |
| timid, branch, warn, concurrency, |
| ): |
| """Create a collector. |
| |
| `should_trace` is a function, taking a file name and a frame, and |
| returning a `coverage.FileDisposition object`. |
| |
| `check_include` is a function taking a file name and a frame. It returns |
| a boolean: True if the file should be traced, False if not. |
| |
| `should_start_context` is a function taking a frame, and returning a |
| string. If the frame should be the start of a new context, the string |
| is the new context. If the frame should not be the start of a new |
| context, return None. |
| |
| `file_mapper` is a function taking a filename, and returning a Unicode |
| filename. The result is the name that will be recorded in the data |
| file. |
| |
| If `timid` is true, then a slower simpler trace function will be |
| used. This is important for some environments where manipulation of |
| tracing functions make the faster more sophisticated trace function not |
| operate properly. |
| |
| If `branch` is true, then branches will be measured. This involves |
| collecting data on which statements followed each other (arcs). Use |
| `get_arc_data` to get the arc data. |
| |
| `warn` is a warning function, taking a single string message argument |
| and an optional slug argument which will be a string or None, to be |
| used if a warning needs to be issued. |
| |
| `concurrency` is a list of strings indicating the concurrency libraries |
| in use. Valid values are "greenlet", "eventlet", "gevent", or "thread" |
| (the default). Of these four values, only one can be supplied. Other |
| values are ignored. |
| |
| """ |
| self.should_trace = should_trace |
| self.check_include = check_include |
| self.should_start_context = should_start_context |
| self.file_mapper = file_mapper |
| self.warn = warn |
| self.branch = branch |
| self.threading = None |
| self.covdata = None |
| |
| self.static_context = None |
| |
| self.origin = short_stack() |
| |
| self.concur_id_func = None |
| self.mapped_file_cache = {} |
| |
| # We can handle a few concurrency options here, but only one at a time. |
| these_concurrencies = self.SUPPORTED_CONCURRENCIES.intersection(concurrency) |
| if len(these_concurrencies) > 1: |
| raise CoverageException("Conflicting concurrency settings: %s" % concurrency) |
| self.concurrency = these_concurrencies.pop() if these_concurrencies else '' |
| |
| try: |
| if self.concurrency == "greenlet": |
| import greenlet |
| self.concur_id_func = greenlet.getcurrent |
| elif self.concurrency == "eventlet": |
| import eventlet.greenthread # pylint: disable=import-error,useless-suppression |
| self.concur_id_func = eventlet.greenthread.getcurrent |
| elif self.concurrency == "gevent": |
| import gevent # pylint: disable=import-error,useless-suppression |
| self.concur_id_func = gevent.getcurrent |
| elif self.concurrency == "thread" or not self.concurrency: |
| # It's important to import threading only if we need it. If |
| # it's imported early, and the program being measured uses |
| # gevent, then gevent's monkey-patching won't work properly. |
| import threading |
| self.threading = threading |
| else: |
| raise CoverageException("Don't understand concurrency=%s" % concurrency) |
| except ImportError: |
| raise CoverageException( |
| "Couldn't trace with concurrency=%s, the module isn't installed." % ( |
| self.concurrency, |
| ) |
| ) |
| |
| self.reset() |
| |
| if timid: |
| # Being timid: use the simple Python trace function. |
| self._trace_class = PyTracer |
| else: |
| # Being fast: use the C Tracer if it is available, else the Python |
| # trace function. |
| self._trace_class = CTracer or PyTracer |
| |
| if self._trace_class is CTracer: |
| self.file_disposition_class = CFileDisposition |
| self.supports_plugins = True |
| else: |
| self.file_disposition_class = FileDisposition |
| self.supports_plugins = False |
| |
| def __repr__(self): |
| return "<Collector at 0x%x: %s>" % (id(self), self.tracer_name()) |
| |
| def use_data(self, covdata, context): |
| """Use `covdata` for recording data.""" |
| self.covdata = covdata |
| self.static_context = context |
| self.covdata.set_context(self.static_context) |
| |
| def tracer_name(self): |
| """Return the class name of the tracer we're using.""" |
| return self._trace_class.__name__ |
| |
| def _clear_data(self): |
| """Clear out existing data, but stay ready for more collection.""" |
| # We used to used self.data.clear(), but that would remove filename |
| # keys and data values that were still in use higher up the stack |
| # when we are called as part of switch_context. |
| for d in self.data.values(): |
| d.clear() |
| |
| for tracer in self.tracers: |
| tracer.reset_activity() |
| |
| def reset(self): |
| """Clear collected data, and prepare to collect more.""" |
| # A dictionary mapping file names to dicts with line number keys (if not |
| # branch coverage), or mapping file names to dicts with line number |
| # pairs as keys (if branch coverage). |
| self.data = {} |
| |
| # A dictionary mapping file names to file tracer plugin names that will |
| # handle them. |
| self.file_tracers = {} |
| |
| self.disabled_plugins = set() |
| |
| # The .should_trace_cache attribute is a cache from file names to |
| # coverage.FileDisposition objects, or None. When a file is first |
| # considered for tracing, a FileDisposition is obtained from |
| # Coverage.should_trace. Its .trace attribute indicates whether the |
| # file should be traced or not. If it should be, a plugin with dynamic |
| # file names can decide not to trace it based on the dynamic file name |
| # being excluded by the inclusion rules, in which case the |
| # FileDisposition will be replaced by None in the cache. |
| if env.PYPY: |
| import __pypy__ # pylint: disable=import-error |
| # Alex Gaynor said: |
| # should_trace_cache is a strictly growing key: once a key is in |
| # it, it never changes. Further, the keys used to access it are |
| # generally constant, given sufficient context. That is to say, at |
| # any given point _trace() is called, pypy is able to know the key. |
| # This is because the key is determined by the physical source code |
| # line, and that's invariant with the call site. |
| # |
| # This property of a dict with immutable keys, combined with |
| # call-site-constant keys is a match for PyPy's module dict, |
| # which is optimized for such workloads. |
| # |
| # This gives a 20% benefit on the workload described at |
| # https://bitbucket.org/pypy/pypy/issue/1871/10x-slower-than-cpython-under-coverage |
| self.should_trace_cache = __pypy__.newdict("module") |
| else: |
| self.should_trace_cache = {} |
| |
| # Our active Tracers. |
| self.tracers = [] |
| |
| self._clear_data() |
| |
| def _start_tracer(self): |
| """Start a new Tracer object, and store it in self.tracers.""" |
| tracer = self._trace_class() |
| tracer.data = self.data |
| tracer.trace_arcs = self.branch |
| tracer.should_trace = self.should_trace |
| tracer.should_trace_cache = self.should_trace_cache |
| tracer.warn = self.warn |
| |
| if hasattr(tracer, 'concur_id_func'): |
| tracer.concur_id_func = self.concur_id_func |
| elif self.concur_id_func: |
| raise CoverageException( |
| "Can't support concurrency=%s with %s, only threads are supported" % ( |
| self.concurrency, self.tracer_name(), |
| ) |
| ) |
| |
| if hasattr(tracer, 'file_tracers'): |
| tracer.file_tracers = self.file_tracers |
| if hasattr(tracer, 'threading'): |
| tracer.threading = self.threading |
| if hasattr(tracer, 'check_include'): |
| tracer.check_include = self.check_include |
| if hasattr(tracer, 'should_start_context'): |
| tracer.should_start_context = self.should_start_context |
| tracer.switch_context = self.switch_context |
| if hasattr(tracer, 'disable_plugin'): |
| tracer.disable_plugin = self.disable_plugin |
| |
| fn = tracer.start() |
| self.tracers.append(tracer) |
| |
| return fn |
| |
| # The trace function has to be set individually on each thread before |
| # execution begins. Ironically, the only support the threading module has |
| # for running code before the thread main is the tracing function. So we |
| # install this as a trace function, and the first time it's called, it does |
| # the real trace installation. |
| |
| def _installation_trace(self, frame, event, arg): |
| """Called on new threads, installs the real tracer.""" |
| # Remove ourselves as the trace function. |
| sys.settrace(None) |
| # Install the real tracer. |
| fn = self._start_tracer() |
| # Invoke the real trace function with the current event, to be sure |
| # not to lose an event. |
| if fn: |
| fn = fn(frame, event, arg) |
| # Return the new trace function to continue tracing in this scope. |
| return fn |
| |
| def start(self): |
| """Start collecting trace information.""" |
| if self._collectors: |
| self._collectors[-1].pause() |
| |
| self.tracers = [] |
| |
| # Check to see whether we had a fullcoverage tracer installed. If so, |
| # get the stack frames it stashed away for us. |
| traces0 = [] |
| fn0 = sys.gettrace() |
| if fn0: |
| tracer0 = getattr(fn0, '__self__', None) |
| if tracer0: |
| traces0 = getattr(tracer0, 'traces', []) |
| |
| try: |
| # Install the tracer on this thread. |
| fn = self._start_tracer() |
| except: |
| if self._collectors: |
| self._collectors[-1].resume() |
| raise |
| |
| # If _start_tracer succeeded, then we add ourselves to the global |
| # stack of collectors. |
| self._collectors.append(self) |
| |
| # Replay all the events from fullcoverage into the new trace function. |
| for args in traces0: |
| (frame, event, arg), lineno = args |
| try: |
| fn(frame, event, arg, lineno=lineno) |
| except TypeError: |
| raise Exception("fullcoverage must be run with the C trace function.") |
| |
| # Install our installation tracer in threading, to jump-start other |
| # threads. |
| if self.threading: |
| self.threading.settrace(self._installation_trace) |
| |
| def stop(self): |
| """Stop collecting trace information.""" |
| assert self._collectors |
| if self._collectors[-1] is not self: |
| print("self._collectors:") |
| for c in self._collectors: |
| print(" {!r}\n{}".format(c, c.origin)) |
| assert self._collectors[-1] is self, ( |
| "Expected current collector to be %r, but it's %r" % (self, self._collectors[-1]) |
| ) |
| |
| self.pause() |
| |
| # Remove this Collector from the stack, and resume the one underneath |
| # (if any). |
| self._collectors.pop() |
| if self._collectors: |
| self._collectors[-1].resume() |
| |
| def pause(self): |
| """Pause tracing, but be prepared to `resume`.""" |
| for tracer in self.tracers: |
| tracer.stop() |
| stats = tracer.get_stats() |
| if stats: |
| print("\nCoverage.py tracer stats:") |
| for k in sorted(stats.keys()): |
| print("%20s: %s" % (k, stats[k])) |
| if self.threading: |
| self.threading.settrace(None) |
| |
| def resume(self): |
| """Resume tracing after a `pause`.""" |
| for tracer in self.tracers: |
| tracer.start() |
| if self.threading: |
| self.threading.settrace(self._installation_trace) |
| else: |
| self._start_tracer() |
| |
| def _activity(self): |
| """Has any activity been traced? |
| |
| Returns a boolean, True if any trace function was invoked. |
| |
| """ |
| return any(tracer.activity() for tracer in self.tracers) |
| |
| def switch_context(self, new_context): |
| """Switch to a new dynamic context.""" |
| self.flush_data() |
| if self.static_context: |
| context = self.static_context |
| if new_context: |
| context += "|" + new_context |
| else: |
| context = new_context |
| self.covdata.set_context(context) |
| |
| def disable_plugin(self, disposition): |
| """Disable the plugin mentioned in `disposition`.""" |
| file_tracer = disposition.file_tracer |
| plugin = file_tracer._coverage_plugin |
| plugin_name = plugin._coverage_plugin_name |
| self.warn("Disabling plug-in {!r} due to previous exception".format(plugin_name)) |
| plugin._coverage_enabled = False |
| disposition.trace = False |
| |
| def cached_mapped_file(self, filename): |
| """A locally cached version of file names mapped through file_mapper.""" |
| key = (type(filename), filename) |
| try: |
| return self.mapped_file_cache[key] |
| except KeyError: |
| return self.mapped_file_cache.setdefault(key, self.file_mapper(filename)) |
| |
| def mapped_file_dict(self, d): |
| """Return a dict like d, but with keys modified by file_mapper.""" |
| # The call to litems() ensures that the GIL protects the dictionary |
| # iterator against concurrent modifications by tracers running |
| # in other threads. We try three times in case of concurrent |
| # access, hoping to get a clean copy. |
| runtime_err = None |
| for _ in range(3): |
| try: |
| items = litems(d) |
| except RuntimeError as ex: |
| runtime_err = ex |
| else: |
| break |
| else: |
| raise runtime_err |
| |
| return dict((self.cached_mapped_file(k), v) for k, v in items if v) |
| |
| def plugin_was_disabled(self, plugin): |
| """Record that `plugin` was disabled during the run.""" |
| self.disabled_plugins.add(plugin._coverage_plugin_name) |
| |
| def flush_data(self): |
| """Save the collected data to our associated `CoverageData`. |
| |
| Data may have also been saved along the way. This forces the |
| last of the data to be saved. |
| |
| Returns True if there was data to save, False if not. |
| """ |
| if not self._activity(): |
| return False |
| |
| if self.branch: |
| self.covdata.add_arcs(self.mapped_file_dict(self.data)) |
| else: |
| self.covdata.add_lines(self.mapped_file_dict(self.data)) |
| |
| file_tracers = { |
| k: v for k, v in self.file_tracers.items() |
| if v not in self.disabled_plugins |
| } |
| self.covdata.add_file_tracers(self.mapped_file_dict(file_tracers)) |
| |
| self._clear_data() |
| return True |
