diff options
Diffstat (limited to 'python/helpers/coverage/collector.py')
| -rw-r--r-- | python/helpers/coverage/collector.py | 74 |
1 files changed, 61 insertions, 13 deletions
diff --git a/python/helpers/coverage/collector.py b/python/helpers/coverage/collector.py index 9c40d16c7b19..8ba7d87cd4e0 100644 --- a/python/helpers/coverage/collector.py +++ b/python/helpers/coverage/collector.py @@ -1,13 +1,24 @@ """Raw data collector for Coverage.""" -import sys, threading +import os, sys, threading try: # Use the C extension code when we can, for speed. - from coverage.tracer import Tracer + from coverage.tracer import CTracer # pylint: disable=F0401,E0611 except ImportError: # Couldn't import the C extension, maybe it isn't built. - Tracer = None + if os.getenv('COVERAGE_TEST_TRACER') == 'c': + # During testing, we use the COVERAGE_TEST_TRACER env var 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 PyTracer(object): @@ -40,12 +51,19 @@ class PyTracer(object): self.last_exc_back = None self.last_exc_firstlineno = 0 self.arcs = False + self.thread = None + self.stopped = False def _trace(self, frame, event, arg_unused): """The trace function passed to sys.settrace.""" - #print("trace event: %s %r @%d" % ( - # event, frame.f_code.co_filename, frame.f_lineno)) + if self.stopped: + return + + if 0: + sys.stderr.write("trace event: %s %r @%d\n" % ( + event, frame.f_code.co_filename, frame.f_lineno + )) if self.last_exc_back: if frame == self.last_exc_back: @@ -61,10 +79,11 @@ class PyTracer(object): # in this file. self.data_stack.append((self.cur_file_data, self.last_line)) filename = frame.f_code.co_filename - tracename = self.should_trace_cache.get(filename) - if tracename is None: + if filename not in self.should_trace_cache: tracename = self.should_trace(filename, frame) self.should_trace_cache[filename] = tracename + else: + tracename = self.should_trace_cache[filename] #print("called, stack is %d deep, tracename is %r" % ( # len(self.data_stack), tracename)) if tracename: @@ -105,15 +124,24 @@ class PyTracer(object): Return a Python function suitable for use with sys.settrace(). """ + self.thread = threading.currentThread() sys.settrace(self._trace) return self._trace def stop(self): """Stop this Tracer.""" + self.stopped = True + if self.thread != threading.currentThread(): + # Called on a different thread than started us: we can't unhook + # ourseves, but we've set the flag that we should stop, so we won't + # do any more tracing. + return + if hasattr(sys, "gettrace") and self.warn: if sys.gettrace() != self._trace: msg = "Trace function changed, measurement is likely wrong: %r" - self.warn(msg % sys.gettrace()) + self.warn(msg % (sys.gettrace(),)) + #print("Stopping tracer on %s" % threading.current_thread().ident) sys.settrace(None) def get_stats(self): @@ -146,7 +174,7 @@ class Collector(object): """Create a collector. `should_trace` is a function, taking a filename, and returning a - canonicalized filename, or False depending on whether the file should + canonicalized filename, or None depending on whether the file should be traced or not. If `timid` is true, then a slower simpler trace function will be @@ -173,7 +201,7 @@ class Collector(object): else: # Being fast: use the C Tracer if it is available, else the Python # trace function. - self._trace_class = Tracer or PyTracer + self._trace_class = CTracer or PyTracer def __repr__(self): return "<Collector at 0x%x>" % id(self) @@ -190,7 +218,7 @@ class Collector(object): # A cache of the results from should_trace, the decision about whether # to trace execution in a file. A dict of filename to (filename or - # False). + # None). self.should_trace_cache = {} # Our active Tracers. @@ -232,9 +260,29 @@ class Collector(object): if self._collectors: self._collectors[-1].pause() self._collectors.append(self) - #print >>sys.stderr, "Started: %r" % self._collectors + #print("Started: %r" % self._collectors, file=sys.stderr) + + # Check to see whether we had a fullcoverage tracer installed. + traces0 = [] + if hasattr(sys, "gettrace"): + fn0 = sys.gettrace() + if fn0: + tracer0 = getattr(fn0, '__self__', None) + if tracer0: + traces0 = getattr(tracer0, 'traces', []) + # Install the tracer on this thread. - self._start_tracer() + fn = self._start_tracer() + + 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. threading.settrace(self._installation_trace) |