[LNT] Python 3 support: Fix implicit package-relative imports

[hubert.reinterpretcast]

Summary

This patch replaces implicit package-relative imports with explicitly relative imports and makes further adjustments necessary to correct for circular import issues encountered when running with Python 2.7 following the initial changes.

Finally, from __future__ import absolute_import is added to all of the files changed as part of this exercise.

These changes help with running tests (without result submission) with Python 3.

[thopre]

lnt/server/db/testsuite.py

117

I have a slightly different patch that breaks the circular dependency altogether by moving some things from testsuitedb to testsuite. From what I read online it is a better approach, as people seems to suggest local import to break circular dependencies is more of a workaround. I have no opinion myself.

[hubert.reinterpretcast]

lnt/server/db/testsuite.py

117

Thanks. I agree this is more of a workaround. I see that you posted D67811 and indicated that you're open to rebasing after this patch lands. I think the effect would be a reduction in the size of your patch (which would help make it easier to review), so I'll work on committing this.

lnt/external/stats/pstat.py

 ## 12/05/98 ... updated doc-strings
 ##              added features to collapse() function
 ##              added flat() function for lists
 ##              fixed a broken asortrows() 
 ## 11/16/98 ... fixed minor bug in aput for 1D arrays
 ##
 ## 11/08/98 ... fixed aput to output large arrays correctly
 
+from __future__ import absolute_import
 from __future__ import print_function
-import stats  # required 3rd party module
 import string, copy
 from types import *
 
 __version__ = 0.4
 
 ###===========================  LIST FUNCTIONS  ==========================
 ###
 ### Here are the list functions, DEFINED FOR ALL SYSTEMS.

lnt/external/stats/stats.py

 ## 12/01/98 ... added anova() function (requires NumPy)
 ##              incorporated Dispatch class
 ## 11/12/98 ... added functionality to amean, aharmonicmean, ageometricmean
 ##              added 'asum' function (added functionality to N.add.reduce)
 ##              fixed both moment and amoment (two errors)
 ##              changed name of skewness and askewness to skew and askew
 ##              fixed (a)histogram (which sometimes counted points <lowerlimit)
 
+from __future__ import absolute_import
 from __future__ import print_function
-import pstat               # required 3rd party module
+from . import pstat        # required 3rd party module
 import math, string, copy  # required python modules
 from types import *
 
 __version__ = 0.6
 
 ############# DISPATCH CODE ##############
 
 

lnt/formats/__init__.py

 """
 Utilities for converting to LNT's test format.
 
 LNT formats are described by dictionaries with 'name', 'read', and 'write'
 fields. Only the 'name' field is required. The 'read' field should be a
 callable taking a path_or_file object, the 'write' function should be a
 callable taking a Python object to write, and the path_or_file to write to.
 """
 
-from PlistFormat import format as plist
-from JSONFormat import format as json
+from __future__ import absolute_import
+from .PlistFormat import format as plist
+from .JSONFormat import format as json
 
 formats = [plist, json]
 formats_by_name = dict((f['name'], f) for f in formats)
 format_names = list(formats_by_name.keys())
 
 
 def get_format(name):
     """get_format(name) -> [format]

lnt/lnttool/__init__.py

-from main import main
+from __future__ import absolute_import
+from .main import main

lnt/server/db/testsuite.py

 """
 Database models for the TestSuites abstraction.
 """
 
+from __future__ import absolute_import
 import json
 import lnt
-import testsuitedb
-import util
+from . import util
 
 import sqlalchemy
 import sqlalchemy.ext.declarative
 import sqlalchemy.orm
 from sqlalchemy import Column, Integer, ForeignKey, String, Binary
 from sqlalchemy.orm import relation
 from lnt.util import logger
 
def __init__(self, name, db_key_name):
                                   lnt.__versioninfo__[1])
 
     def __repr__(self):
         return '%s%r' % (self.__class__.__name__, (self.name, self.db_key_name,
                                                    self.version))
 
     @staticmethod
     def from_json(data):
+        from . import testsuitedb
         if data.get('format_version') != '2':
             raise ValueError("Expected \"format_version\": \"2\" in schema")
         name = data['name']
         ts = TestSuite(name=data['name'], db_key_name=data['name'])
 
         machine_fields = []
         for field_desc in data.get('machine_fields', []):
             name = field_desc['name']
class SampleField(FieldMixin, Base):
     def copy_info(self, other):
         self.display_name = other.display_name
         self.unit = other.unit
         self.unit_abbrev = other.unit_abbrev
         self.schema_index = other.schema_index
 
 
 def _upgrade_to(connectable, tsschema, new_schema, dry_run=False):
+    from . import testsuitedb
     new = json.loads(new_schema.jsonschema)
     old = json.loads(tsschema.jsonschema)
     ts_name = new['name']
     if old['name'] != ts_name:
         raise _MigrationError("Schema names differ?!?")
 
     old_metrics = {}
     for metric_desc in old.get('metrics', []):

lnt/server/db/testsuitedb.py

 """
 Database models for the TestSuite databases themselves.
 
 These are a bit magical because the models themselves are driven by the test
 suite metadata, so we only create the classes at runtime.
 """
 
+from __future__ import absolute_import
 import datetime
 import json
 import os
 
 import aniso8601
 import sqlalchemy
 import flask
 from sqlalchemy import Float, String, Integer, Column, ForeignKey, Binary, DateTime
 from sqlalchemy.orm import relation
 from sqlalchemy.orm.exc import ObjectDeletedError
 from typing import List
 from lnt.util import logger
 
-import testsuite
+from . import testsuite
 import lnt.testing.profile.profile as profile
 import lnt
 from lnt.server.ui.util import convert_revision
 
 
 def _dict_update_abort_on_duplicates(base_dict, to_merge):
     '''This behaves like base_dict.update(to_merge) but asserts that none
     of the keys in to_merge is present in base_dict yet.'''

lnt/testing/profile/__init__.py

 # This is the profile implementation registry. Register new profile
 # implementations here.
 
-from profilev1impl import ProfileV1
-from profilev2impl import ProfileV2
-from perf import LinuxPerfProfile
+from __future__ import absolute_import
+from .profilev1impl import ProfileV1
+from .profilev2impl import ProfileV2
+from .perf import LinuxPerfProfile
 IMPLEMENTATIONS = {0: LinuxPerfProfile, 1: ProfileV1, 2: ProfileV2}

lnt/testing/profile/perf.py

+from __future__ import absolute_import
 from lnt.util import logger
-from profile import ProfileImpl
-from profilev1impl import ProfileV1
+from .profile import ProfileImpl
+from .profilev1impl import ProfileV1
 
 import os
 import traceback
 
 try:
     import cPerf
 except Exception:
     pass

lnt/testing/profile/profilev2impl.py

-from profile import ProfileImpl
+from __future__ import absolute_import
+from .profile import ProfileImpl
 import StringIO
 import bz2
 import copy
 import io
 import os
 import struct
 
 """