Bug 1305743 - Make failure to find mozinfo.json a fatal error r=gbrown,ahal a=reland

- moved placement of the raise_exception computation to be after the initial objdir path computation.
- original implementation was missing detection for cases where user may pass in a False flag to explicitly suppress errors.
- added unit tests to check for scenarios where raise_exception flag is passed in as part of positional argument.
- changed argument to include a **kwargs argument for caller to modify default exception behavior.
- default behavior is to raise exceptions if mozinfo.json cannot be found.
- disabled TreeMetadataEmitter from calling mozinfo.find_and_update_from_json and setting the self.info variable since it was not referenced anywhere else after the initial setup.

Depends on D6859

Differential Revision: https://phabricator.services.mozilla.com/D6860

--HG--
extra : source : 6d25c44c39ea33ebe25829d945b00963dad39ea4
extra : amend_source : 5c7a556b122f887113bae16356ffcf4bd064b620

python/mozbuild/mozbuild/frontend/emitter.py

@@ -110,18 +110,6 @@ class TreeMetadataEmitter(LoggingMixin):
         self.populate_logger()
 
         self.config = config
-
-        mozinfo.find_and_update_from_json(config.topobjdir)
-
-        # Python 2.6 doesn't allow unicode keys to be used for keyword
-        # arguments. This gross hack works around the problem until we
-        # rid ourselves of 2.6.
-        self.info = {}
-        for k, v in mozinfo.info.items():
-            if isinstance(k, unicode):
-                k = k.encode('ascii')
-            self.info[k] = v
-
         self._libs = OrderedDefaultDict(list)
         self._binaries = OrderedDict()
         self._compile_dirs = set()

testing/mozbase/mozinfo/mozinfo/mozinfo.py

@@ -183,13 +183,14 @@ def sanitize(info):
 
 
 def update(new_info):
-    """
-    Update the info.
+    """Adds information from json file to the global symbol table.
+
+    Given the parameter new_info, this method will look for the file.
+    If found, the file is read into a buffer and assumed to be json.
 
     :param new_info: Either a dict containing the new info or a path/url
                      to a json file containing the new info.
     """
-
     PY3 = sys.version_info[0] == 3
     if PY3:
         string_types = str,
@@ -215,16 +216,29 @@ def update(new_info):
         globals()['isUnix'] = True
 
 
-def find_and_update_from_json(*dirs):
-    """
-    Find a mozinfo.json file, load it, and update the info with the
-    contents.
+def find_and_update_from_json(*dirs, **kwargs):
+    """Find a mozinfo.json file, load it, and update global symbol table.
 
-    :param dirs: Directories in which to look for the file. They will be
-                 searched after first looking in the root of the objdir
-                 if the current script is being run from a Mozilla objdir.
+    This method will first check the relevant objdir directory for the
+    necessary mozinfo.json file, if the current script is being run from a
+    Mozilla objdir.
 
-    Returns the full path to mozinfo.json if it was found, or None otherwise.
+    If the objdir directory did not supply the necessary data, this method
+    will then look for the required mozinfo.json file from the provided
+    tuple of directories.
+
+    If file is found, the global symbols table is updated via a helper method.
+
+    If no valid files are found, an exception is raised.
+
+    :param tuple dirs: Directories in which to look for the file.
+    :param dict kwargs: optional values:
+                        raise_exception: if this value is provided, the default
+                                         behavior of raising an exception is
+                                         overridden.
+    :returns: EnvironmentError: default behavior.
+              None: if exception raising is suppressed.
+              json_path: string representation of path.
     """
     # First, see if we're in an objdir
     try:
@@ -240,6 +254,8 @@ def find_and_update_from_json(*dirs):
     except (BuildEnvironmentNotFoundException, MozconfigFindException):
         pass
 
+    raise_exception = kwargs.get('raise_exception', True)
+
     for d in dirs:
         d = _os.path.abspath(d)
         json_path = _os.path.join(d, "mozinfo.json")
@@ -247,7 +263,10 @@ def find_and_update_from_json(*dirs):
             update(json_path)
             return json_path
 
-    return None
+    if raise_exception:
+        raise EnvironmentError('{}: could not find any mozinfo.json.'.format(__name__))
+    else:
+        return None
 
 
 def output_to_file(path):

testing/mozbase/mozinfo/tests/test.py

@@ -75,6 +75,13 @@ class TestMozinfo(unittest.TestCase):
         self.assertEqual(mozinfo.find_and_update_from_json(self.tempdir), j)
         self.assertEqual(mozinfo.info["foo"], "abcdefg")
 
+    def test_find_and_update_file_no_argument(self):
+        """Test that mozinfo.find_and_update_from_json can
+        handle not being given any arguments.
+        """
+        with self.assertRaises(EnvironmentError):
+            self.assertEqual(mozinfo.find_and_update_from_json())
+
     def test_find_and_update_file_invalid_json(self):
         """Test that mozinfo.find_and_update_from_json can
         handle invalid JSON"""
@@ -83,6 +90,42 @@ class TestMozinfo(unittest.TestCase):
             f.write('invalid{"json":')
         self.assertRaises(ValueError, mozinfo.find_and_update_from_json, self.tempdir)
 
+    def test_find_and_update_file_raise_exception(self):
+        """Test that mozinfo.find_and_update_from_json raises
+        an IOError exception if a True boolean value is
+        provided as the only argument.
+        """
+        with self.assertRaises(EnvironmentError):
+            mozinfo.find_and_update_from_json(raise_exception=True)
+
+    def test_find_and_update_file_raise_exception_multiple_arguments(self):
+        """Test that mozinfo.find_and_update_from_json raises
+        an IOError exception if a True boolean value is
+        provided as last positional argument.
+        """
+        with self.assertRaises(EnvironmentError):
+            mozinfo.find_and_update_from_json(self.tempdir, raise_exception=True)
+
+    def test_find_and_update_file_suppress_exception(self):
+        """Test that mozinfo.find_and_update_from_json suppresses
+        an IOError exception if a False boolean value is
+        provided as the only argument.
+        """
+        self.assertEqual(mozinfo.find_and_update_from_json(
+            raise_exception=False), None)
+
+    def test_find_and_update_file_suppress_exception_multiple_arguments(self):
+        """Test that mozinfo.find_and_update_from_json suppresses
+        an IOError exception if a False boolean value is
+        provided as last positional argument.
+        """
+        j = os.path.join(self.tempdir, "mozinfo.json")
+        with open(j, "w") as f:
+            f.write(json.dumps({"foo": "abcdefg"}))
+        self.assertEqual(mozinfo.find_and_update_from_json(
+            self.tempdir, raise_exception=False), j)
+        self.assertEqual(mozinfo.info["foo"], "abcdefg")
+
     def test_find_and_update_file_mozbuild(self):
         """Test that mozinfo.find_and_update_from_json can
         find mozinfo.json using the mozbuild module."""