Slight refactor of how we look for configuration files

2 files changed, 47 insertions, 29 deletions

diff --git a/coverage/config.py b/coverage/config.py
index 7b8f2bd..260dafd 100644
--- a/coverage/config.py
+++ b/coverage/config.py
@@ -175,8 +175,12 @@ class CoverageConfig(object):
     def __init__(self):
         """Initialize the configuration attributes to their defaults."""
         # Metadata about the config.
+        # We tried to read these config files.
         self.attempted_config_files = []
-        self.config_files = []
+        # We did read these config files, but maybe didn't find any content for us.
+        self.config_files_read = []
+        # The file that gave us our configuration.
+        self.config_file = None
 
         # Defaults for [run] and [report]
         self._include = None
@@ -262,7 +266,7 @@ class CoverageConfig(object):
         if not files_read:
             return False
 
-        self.config_files.extend(files_read)
+        self.config_files_read.extend(files_read)
 
         any_set = False
         try:
@@ -305,9 +309,14 @@ class CoverageConfig(object):
         # then it was used.  If we're piggybacking on someone else's file,
         # then it was only used if we found some settings in it.
         if our_file:
-            return True
+            used = True
         else:
-            return any_set
+            used = any_set
+
+        if used:
+            self.config_file = filename
+
+        return used
 
     CONFIG_FILE_OPTIONS = [
         # These are *args for _set_attr_from_config_option:
@@ -425,6 +434,28 @@ class CoverageConfig(object):
         raise CoverageException("No such option: %r" % option_name)
 
 
+def config_files_to_try(config_file):
+    """What config files should we try to read?
+
+    Returns a list of tuples:
+        (filename, is_our_file, was_file_specified)
+    """
+
+    # Some API users were specifying ".coveragerc" to mean the same as
+    # True, so make it so.
+    if config_file == ".coveragerc":
+        config_file = True
+    specified_file = (config_file is not True)
+    if not specified_file:
+        config_file = ".coveragerc"
+    files_to_try = [
+        (config_file, True, specified_file),
+        ("setup.cfg", False, False),
+        ("tox.ini", False, False),
+    ]
+    return files_to_try
+
+
 def read_coverage_config(config_file, **kwargs):
     """Read the coverage.py configuration.
 
@@ -435,10 +466,7 @@ def read_coverage_config(config_file, **kwargs):
             setting values in the configuration.
 
     Returns:
-        config_file, config:
-            config_file is the value to use for config_file in other
-            invocations of coverage.
-
+        config:
             config is a CoverageConfig object read from the appropriate
             configuration file.
 
@@ -449,25 +477,14 @@ def read_coverage_config(config_file, **kwargs):
 
     # 2) from a file:
     if config_file:
-        # Some API users were specifying ".coveragerc" to mean the same as
-        # True, so make it so.
-        if config_file == ".coveragerc":
-            config_file = True
-        specified_file = (config_file is not True)
-        if not specified_file:
-            config_file = ".coveragerc"
-
-        for fname, our_file in [(config_file, True),
-                                ("setup.cfg", False),
-                                ("tox.ini", False)]:
-            config_read = config.from_file(fname, our_file=our_file)
-            is_config_file = fname == config_file
-
-            if not config_read and is_config_file and specified_file:
-                raise CoverageException("Couldn't read '%s' as a config file" % fname)
+        files_to_try = config_files_to_try(config_file)
 
+        for fname, our_file, specified_file in files_to_try:
+            config_read = config.from_file(fname, our_file=our_file)
             if config_read:
                 break
+            if our_file and specified_file:
+                raise CoverageException("Couldn't read '%s' as a config file" % fname)
 
     # 3) from environment variables:
     env_data_file = os.environ.get('COVERAGE_FILE')
@@ -486,4 +503,4 @@ def read_coverage_config(config_file, **kwargs):
     config.html_dir = os.path.expanduser(config.html_dir)
     config.xml_output = os.path.expanduser(config.xml_output)
 
-    return config_file, config
+    return config
diff --git a/coverage/control.py b/coverage/control.py
index b1d95eb..80012f5 100644
--- a/coverage/control.py
+++ b/coverage/control.py
@@ -128,7 +128,7 @@ class Coverage(object):
 
         """
         # Build our configuration from a number of sources.
-        self._config_file, self.config = read_coverage_config(
+        self.config = read_coverage_config(
             config_file=config_file,
             data_file=data_file, cover_pylib=cover_pylib, timid=timid,
             branch=branch, parallel=bool_or_none(data_suffix),
@@ -220,7 +220,7 @@ class Coverage(object):
                 raise CoverageException(                    # pragma: only jython
                     "multiprocessing is not supported on this Python"
                 )
-            patch_multiprocessing(rcfile=self._config_file)
+            patch_multiprocessing(rcfile=self.config.config_file)
             # Multi-processing uses parallel for the subprocesses, so also use
             # it for the main process.
             self.config.parallel = True
@@ -828,8 +828,9 @@ class Coverage(object):
             ('tracer', self._collector.tracer_name()),
             ('plugins.file_tracers', plugin_info(self._plugins.file_tracers)),
             ('plugins.configurers', plugin_info(self._plugins.configurers)),
-            ('config_files', self.config.attempted_config_files),
-            ('configs_read', self.config.config_files),
+            ('configs_attempted', self.config.attempted_config_files),
+            ('configs_read', self.config.config_files_read),
+            ('config_file', self.config.config_file),
             ('data_path', self._data_files.filename),
             ('python', sys.version.replace('\n', '')),
             ('platform', platform.platform()),