A way to see the raw data in the data file.

3 files changed, 41 insertions, 6 deletions

diff --git a/coverage/cmdline.py b/coverage/cmdline.py
index 7d014902..b15eb107 100644
--- a/coverage/cmdline.py
+++ b/coverage/cmdline.py
@@ -8,7 +8,7 @@ import traceback
 
 from coverage import env
 from coverage.execfile import run_python_file, run_python_module
-from coverage.misc import CoverageException, ExceptionDuringRun, NoSource
+from coverage.misc import CoverageException, ExceptionDuringRun, NoSource, pretty_data
 from coverage.debug import info_formatter, info_header
 
 
@@ -589,9 +589,9 @@ class CoverageScript(object):
                 data = self.coverage.data
                 print(info_header("data"))
                 print("path: %s" % self.coverage.data_files.filename)
-                print("has_arcs: %r" % data.has_arcs())
-                summary = data.line_counts(fullpath=True)
-                if summary:
+                if data:
+                    print("has_arcs: %r" % data.has_arcs())
+                    summary = data.line_counts(fullpath=True)
                     filenames = sorted(summary.keys())
                     print("\n%d files:" % len(filenames))
                     for f in filenames:
@@ -602,6 +602,13 @@ class CoverageScript(object):
                         print(line)
                 else:
                     print("No data collected")
+            elif info == 'rawdata':
+                self.coverage.load()
+                if self.coverage.data:
+                    data = self.coverage.data._read_raw_data_file(self.coverage.config.data_file)
+                    print(pretty_data(data))
+                else:
+                    print("No data collected")
             else:
                 self.help_fn("Don't know what you mean by %r" % info)
                 return ERR
diff --git a/coverage/data.py b/coverage/data.py
index 3eb51bf3..2f1cf442 100644
--- a/coverage/data.py
+++ b/coverage/data.py
@@ -200,13 +200,21 @@ class CoverageData(object):
 
     __bool__ = __nonzero__
 
+    def _open_for_reading(self, filename):
+        """Open a file appropriately for reading data."""
+        return open(filename, "r")
+
+    def _read_raw_data(self, file_obj):
+        """Read the raw data from a file object."""
+        return json.load(file_obj)
+
     def read(self, file_obj):
         """Read the coverage data from the given file object.
 
         Should only be used on an empty CoverageData object.
 
         """
-        data = json.load(file_obj)
+        data = self._read_raw_data(file_obj)
 
         self._lines = data.get('lines', {})
         self._arcs = dict(
@@ -220,7 +228,7 @@ class CoverageData(object):
         if self._debug and self._debug.should('dataio'):
             self._debug.write("Reading data from %r" % (filename,))
         try:
-            with open(filename, "r") as f:
+            with self._open_for_reading(filename) as f:
                 self.read(f)
         except Exception as exc:
             raise CoverageException(
@@ -229,6 +237,11 @@ class CoverageData(object):
                 )
             )
 
+    def _read_raw_data_file(self, filename):
+        """Read the raw data from a file, for debugging."""
+        with self._open_for_reading(filename) as f:
+            return self._read_raw_data(f)
+
     ##
     ## Writing data
     ##
diff --git a/coverage/misc.py b/coverage/misc.py
index b99fbb81..ca09be7d 100644
--- a/coverage/misc.py
+++ b/coverage/misc.py
@@ -3,7 +3,9 @@
 import errno
 import hashlib
 import inspect
+import json
 import os
+import re
 
 from coverage import env
 from coverage.backward import string_class, to_bytes, unicode_class
@@ -170,6 +172,19 @@ def _needs_to_implement(that, func_name):
         )
 
 
+def pretty_data(data):
+    """Format data as JSON, but as nicely as possible.
+
+    Returns a string.
+
+    """
+    # Start with a basic JSON dump.
+    out = json.dumps(data, indent=4, sort_keys=True)
+    # But pairs of numbers shouldn't be split across lines...
+    out = re.sub(r"\[\s+(-?\d+),\s+(-?\d+)\s+]", r"[\1, \2]", out)
+    return out
+
+
 class CoverageException(Exception):
     """An exception specific to Coverage."""
     pass