Upgrade to coverage 3.7.1 and have it auto-build itself on first use.

third_party/coverage-3.7.1/coverage/control.py

Index: third_party/coverage-3.7.1/coverage/control.py
diff --git a/third_party/coverage-3.6/coverage/control.py b/third_party/coverage-3.7.1/coverage/control.py
similarity index 84%
rename from third_party/coverage-3.6/coverage/control.py
rename to third_party/coverage-3.7.1/coverage/control.py
index afb61370c505d4a2e48a60bccd22231ce2815d74..f75a3dda5b1b479a45e52c50d1390b7d076a8b1f 100644
--- a/third_party/coverage-3.6/coverage/control.py
+++ b/third_party/coverage-3.7.1/coverage/control.py
@@ -3,11 +3,12 @@
 import atexit, os, random, socket, sys
 
 from coverage.annotate import AnnotateReporter
-from coverage.backward import string_class, iitems
+from coverage.backward import string_class, iitems, sorted  # pylint: disable=W0622
 from coverage.codeunit import code_unit_factory, CodeUnit
 from coverage.collector import Collector
 from coverage.config import CoverageConfig
 from coverage.data import CoverageData
+from coverage.debug import DebugControl
 from coverage.files import FileLocator, TreeMatcher, FnmatchMatcher
 from coverage.files import PathAliases, find_python_files, prep_patterns
 from coverage.html import HtmlReporter
@@ -17,6 +18,14 @@ from coverage.results import Analysis, Numbers
 from coverage.summary import SummaryReporter
 from coverage.xmlreport import XmlReporter
 
+# Pypy has some unusual stuff in the "stdlib".  Consider those locations
+# when deciding where the stdlib is.
+try:
+    import _structseq       # pylint: disable=F0401
+except ImportError:
+    _structseq = None
+
+
 class coverage(object):
     """Programmatic access to coverage.py.
 
@@ -33,7 +42,8 @@ class coverage(object):
     """
     def __init__(self, data_file=None, data_suffix=None, cover_pylib=None,
                 auto_data=False, timid=None, branch=None, config_file=True,
-                source=None, omit=None, include=None):
+                source=None, omit=None, include=None, debug=None,
+                debug_file=None):
         """
         `data_file` is the base name of the data file to use, defaulting to
         ".coverage".  `data_suffix` is appended (with a dot) to `data_file` to
@@ -68,6 +78,10 @@ class coverage(object):
         `include` will be measured, files that match `omit` will not.  Each
         will also accept a single string argument.
 
+        `debug` is a list of strings indicating what debugging information is
+        desired. `debug_file` is the file to write debug messages to,
+        defaulting to stderr.
+
         """
         from coverage import __version__
 
@@ -100,9 +114,12 @@ class coverage(object):
         self.config.from_args(
             data_file=data_file, cover_pylib=cover_pylib, timid=timid,
             branch=branch, parallel=bool_or_none(data_suffix),
-            source=source, omit=omit, include=include
+            source=source, omit=omit, include=include, debug=debug,
             )
 
+        # Create and configure the debugging controller.
+        self.debug = DebugControl(self.config.debug, debug_file or sys.stderr)
+
         self.auto_data = auto_data
 
         # _exclude_re is a dict mapping exclusion list names to compiled
@@ -147,7 +164,8 @@ class coverage(object):
         # started rather than wherever the process eventually chdir'd to.
         self.data = CoverageData(
             basename=self.config.data_file,
-            collector="coverage v%s" % __version__
+            collector="coverage v%s" % __version__,
+            debug=self.debug,
             )
 
         # The dirs for files considered "installed with the interpreter".
@@ -158,8 +176,8 @@ class coverage(object):
             # environments (virtualenv, for example), these modules may be
             # spread across a few locations. Look at all the candidate modules
             # we've imported, and take all the different ones.
-            for m in (atexit, os, random, socket):
-                if hasattr(m, "__file__"):
+            for m in (atexit, os, random, socket, _structseq):
+                if m is not None and hasattr(m, "__file__"):
                     m_dir = self._canonical_dir(m)
                     if m_dir not in self.pylib_dirs:
                         self.pylib_dirs.append(m_dir)
@@ -168,7 +186,7 @@ class coverage(object):
         # where we are.
         self.cover_dir = self._canonical_dir(__file__)
 
-        # The matchers for _should_trace, created when tracing starts.
+        # The matchers for _should_trace.
         self.source_match = None
         self.pylib_match = self.cover_match = None
         self.include_match = self.omit_match = None
@@ -201,26 +219,28 @@ class coverage(object):
                 filename = filename[:-9] + ".py"
         return filename
 
-    def _should_trace(self, filename, frame):
-        """Decide whether to trace execution in `filename`
+    def _should_trace_with_reason(self, filename, frame):
+        """Decide whether to trace execution in `filename`, with a reason.
 
         This function is called from the trace function.  As each new file name
         is encountered, this function determines whether it is traced or not.
 
-        Returns a canonicalized filename if it should be traced, False if it
-        should not.
+        Returns a pair of values:  the first indicates whether the file should
+        be traced: it's a canonicalized filename if it should be traced, None
+        if it should not.  The second value is a string, the resason for the
+        decision.
 
         """
         if not filename:
             # Empty string is pretty useless
-            return False
+            return None, "empty string isn't a filename"
 
         if filename.startswith('<'):
             # Lots of non-file execution is represented with artificial
             # filenames like "<string>", "<doctest readme.txt[0]>", or
             # "<exec_function>".  Don't ever trace these executions, since we
             # can't do anything with the data later anyway.
-            return False
+            return None, "not a real filename"
 
         self._check_for_packages()
 
@@ -246,35 +266,41 @@ class coverage(object):
         # stdlib and coverage.py directories.
         if self.source_match:
             if not self.source_match.match(canonical):
-                return False
+                return None, "falls outside the --source trees"
         elif self.include_match:
             if not self.include_match.match(canonical):
-                return False
+                return None, "falls outside the --include trees"
         else:
             # If we aren't supposed to trace installed code, then check if this
             # is near the Python standard library and skip it if so.
             if self.pylib_match and self.pylib_match.match(canonical):
-                return False
+                return None, "is in the stdlib"
 
             # We exclude the coverage code itself, since a little of it will be
             # measured otherwise.
             if self.cover_match and self.cover_match.match(canonical):
-                return False
+                return None, "is part of coverage.py"
 
         # Check the file against the omit pattern.
         if self.omit_match and self.omit_match.match(canonical):
-            return False
+            return None, "is inside an --omit pattern"
 
-        return canonical
+        return canonical, "because we love you"
+
+    def _should_trace(self, filename, frame):
+        """Decide whether to trace execution in `filename`.
 
-    # To log what should_trace returns, change this to "if 1:"
-    if 0:
-        _real_should_trace = _should_trace
-        def _should_trace(self, filename, frame):   # pylint: disable=E0102
-            """A logging decorator around the real _should_trace function."""
-            ret = self._real_should_trace(filename, frame)
-            print("should_trace: %r -> %r" % (filename, ret))
-            return ret
+        Calls `_should_trace_with_reason`, and returns just the decision.
+
+        """
+        canonical, reason = self._should_trace_with_reason(filename, frame)
+        if self.debug.should('trace'):
+            if not canonical:
+                msg = "Not tracing %r: %s" % (filename, reason)
+            else:
+                msg = "Tracing %r" % (filename,)
+            self.debug.write(msg)
+        return canonical
 
     def _warn(self, msg):
         """Use `msg` as a warning."""
@@ -364,6 +390,16 @@ class coverage(object):
         if self.omit:
             self.omit_match = FnmatchMatcher(self.omit)
 
+        # The user may want to debug things, show info if desired.
+        if self.debug.should('config'):
+            self.debug.write("Configuration values:")
+            config_info = sorted(self.config.__dict__.items())
+            self.debug.write_formatted_info(config_info)
+
+        if self.debug.should('sys'):
+            self.debug.write("Debugging info:")
+            self.debug.write_formatted_info(self.sysinfo())
+
         self.collector.start()
         self._started = True
         self._measured = True
@@ -479,29 +515,37 @@ class coverage(object):
         Also warn about various problems collecting data.
 
         """
-        if self._measured:
-            self.data.add_line_data(self.collector.get_line_data())
-            self.data.add_arc_data(self.collector.get_arc_data())
-            self.collector.reset()
-
-            # If there are still entries in the source_pkgs list, then we never
-            # encountered those packages.
-            if self._warn_unimported_source:
-                for pkg in self.source_pkgs:
-                    self._warn("Module %s was never imported." % pkg)
-
-            # Find out if we got any data.
-            summary = self.data.summary()
-            if not summary and self._warn_no_data:
-                self._warn("No data was collected.")
-
-            # Find files that were never executed at all.
-            for src in self.source:
-                for py_file in find_python_files(src):
-                    py_file = self.file_locator.canonical_filename(py_file)
-                    self.data.touch_file(py_file)
-
-            self._measured = False
+        if not self._measured:
+            return
+
+        self.data.add_line_data(self.collector.get_line_data())
+        self.data.add_arc_data(self.collector.get_arc_data())
+        self.collector.reset()
+
+        # If there are still entries in the source_pkgs list, then we never
+        # encountered those packages.
+        if self._warn_unimported_source:
+            for pkg in self.source_pkgs:
+                self._warn("Module %s was never imported." % pkg)
+
+        # Find out if we got any data.
+        summary = self.data.summary()
+        if not summary and self._warn_no_data:
+            self._warn("No data was collected.")
+
+        # Find files that were never executed at all.
+        for src in self.source:
+            for py_file in find_python_files(src):
+                py_file = self.file_locator.canonical_filename(py_file)
+
+                if self.omit_match and self.omit_match.match(py_file):
+                    # Turns out this file was omitted, so don't pull it back
+                    # in as unexecuted.
+                    continue
+
+                self.data.touch_file(py_file)
+
+        self._measured = False
 
     # Backward compatibility with version 1.
     def analysis(self, morf):
@@ -528,8 +572,11 @@ class coverage(object):
         """
         analysis = self._analyze(morf)
         return (
-            analysis.filename, analysis.statements, analysis.excluded,
-            analysis.missing, analysis.missing_formatted()
+            analysis.filename,
+            sorted(analysis.statements),
+            sorted(analysis.excluded),
+            sorted(analysis.missing),
+            analysis.missing_formatted(),
             )
 
     def _analyze(self, it):
@@ -680,11 +727,23 @@ class coverage(object):
             ('executable', sys.executable),
             ('cwd', os.getcwd()),
             ('path', sys.path),
-            ('environment', [
+            ('environment', sorted([
                 ("%s = %s" % (k, v)) for k, v in iitems(os.environ)
                     if re.search(r"^COV|^PY", k)
-                ]),
+                ])),
+            ('command_line', " ".join(getattr(sys, 'argv', ['???']))),
             ]
+        if self.source_match:
+            info.append(('source_match', self.source_match.info()))
+        if self.include_match:
+            info.append(('include_match', self.include_match.info()))
+        if self.omit_match:
+            info.append(('omit_match', self.omit_match.info()))
+        if self.cover_match:
+            info.append(('cover_match', self.cover_match.info()))
+        if self.pylib_match:
+            info.append(('pylib_match', self.pylib_match.info()))
+
         return info