Pylint wrapper silent failure

[russellbrooks]

The pylint wrapper seems to swallow errors when tanking the CLI. In particular, I'd been playing around with isort 5 that'll be supported in newer pylint versions, but also works with previous versions that metaflow supports like pylint 2.4.4

metaflow 2.2.0
pylint 2.4.4
isort 5.4.2

Reproducing from tutorials:

$ python helloworld.py run
Metaflow 2.2.0 executing HelloFlow for user:russell
Validating your flow...
    The graph looks good!
Running pylint...

Running pylint separately shows this error is occurring:

$ pylint helloworld.py
************* Module helloworld
helloworld.py:1:0: C0114: Missing module docstring (missing-module-docstring)
helloworld.py:31:4: R0201: Method could be a function (no-self-use)
Traceback (most recent call last):
  File "/opt/conda/bin/pylint", line 8, in <module>
    sys.exit(run_pylint())
  File "/opt/conda/lib/python3.7/site-packages/pylint/__init__.py", line 23, in run_pylint
    PylintRun(sys.argv[1:])
  File "/opt/conda/lib/python3.7/site-packages/pylint/lint.py", line 1731, in __init__
    linter.check(args)
  File "/opt/conda/lib/python3.7/site-packages/pylint/lint.py", line 1004, in check
    self._do_check(files_or_modules)
  File "/opt/conda/lib/python3.7/site-packages/pylint/lint.py", line 1165, in _do_check
    self.check_astroid_module(ast_node, walker, rawcheckers, tokencheckers)
  File "/opt/conda/lib/python3.7/site-packages/pylint/lint.py", line 1252, in check_astroid_module
    walker.walk(ast_node)
  File "/opt/conda/lib/python3.7/site-packages/pylint/utils/ast_walker.py", line 79, in walk
    callback(astroid)
  File "/opt/conda/lib/python3.7/site-packages/pylint/checkers/imports.py", line 541, in leave_module
    std_imports, ext_imports, loc_imports = self._check_imports_order(node)
  File "/opt/conda/lib/python3.7/site-packages/pylint/checkers/imports.py", line 703, in _check_imports_order
    isort_obj = isort.SortImports(
AttributeError: module 'isort' has no attribute 'SortImports'

Everything works as expected when skipping pylint:

$ python helloworld.py --no-pylint run
Metaflow 2.2.0 executing HelloFlow for user:russell
Validating your flow...
    The graph looks good!
2020-08-17 23:16:58.156 Workflow starting (run-id 19441):
2020-08-17 23:16:58.999 [19441/start/190220 (pid 277)] Task is starting.
2020-08-17 23:17:02.085 [19441/start/190220 (pid 277)] HelloFlow is starting.
2020-08-17 23:17:03.561 [19441/start/190220 (pid 277)] Task finished successfully.
2020-08-17 23:17:04.582 [19441/hello/190221 (pid 310)] Task is starting.
2020-08-17 23:17:07.790 [19441/hello/190221 (pid 310)] Metaflow says: Hi!
2020-08-17 23:17:09.357 [19441/hello/190221 (pid 310)] Task finished successfully.
2020-08-17 23:17:10.387 [19441/end/190222 (pid 345)] Task is starting.
2020-08-17 23:17:13.469 [19441/end/190222 (pid 345)] HelloFlow is all done.
2020-08-17 23:17:15.021 [19441/end/190222 (pid 345)] Task finished successfully.
2020-08-17 23:17:15.265 Done!

Nothing urgent here, but it'd be nice to surface the error from pylint.

[savingoyal]

looks like #294 addressed this issue