Merge remote-tracking branch 'upstream/master' into compat-override

* upstream/master:
  chunk sparse arrays (pydata#3202)
  Annotations for .data_vars() and .coords() (pydata#3207)
  Remove duck_array_ops.as_like_arrays() (pydata#3204)
  Match mypy version between CI and pre-commit hook (pydata#3203)
  BUG fix +test .sel method gives error with float32 values (pydata#3153)
  fix precommit file (pydata#3201)
  Enforce mypy compliance in CI (pydata#3197)

Author: dcherian

.github/PULL_REQUEST_TEMPLATE.md

@@ -2,5 +2,5 @@
 
  - [ ] Closes #xxxx
  - [ ] Tests added
- - [ ] Passes `black .` & `flake8`
+ - [ ] Passes `black . && mypy . && flake8`
  - [ ] Fully documented, including `whats-new.rst` for all changes and `api.rst` for new API

.pre-commit-config.yaml

@@ -10,6 +10,10 @@ repos:
     rev: v2.2.3
     hooks:
       - id: flake8
+  - repo: https://github.com/pre-commit/mirrors-mypy
+    rev: v0.720  # Must match ci/requirements/*.yml
+    hooks:
+      - id: mypy
   # run these occasionally, ref discussion https://github.com/pydata/xarray/pull/3194
   # - repo: https://github.com/asottile/pyupgrade
   #   rev: v1.22.1

azure-pipelines.yml

@@ -75,7 +75,7 @@ jobs:
   - template: ci/azure/install.yml
   - bash: |
       source activate xarray-tests
-      mypy . || exit 0
+      mypy .
     displayName: mypy type checks
 
 - job: Docs

ci/requirements/py36.yml

@@ -15,6 +15,7 @@ dependencies:
   - pytest-env
   - coveralls
   - flake8
+  - mypy==0.720  # Must match .pre-commit-config.yaml
   - numpy>=1.12
   - pandas>=0.19
   - pip
@@ -34,5 +35,4 @@ dependencies:
   - iris>=1.10
   - pydap
   - lxml
-  - pip:
-    - mypy==0.711
+

ci/requirements/py37.yml

@@ -16,6 +16,7 @@ dependencies:
   - pytest-env
   - coveralls
   - flake8
+  - mypy==0.720  # Must match .pre-commit-config.yaml
   - numpy>=1.12
   - pandas>=0.19
   - pip
@@ -32,5 +33,4 @@ dependencies:
   - lxml
   - pydap
   - pip:
-    - mypy==0.650
     - numbagg

doc/whats-new.rst

@@ -13,31 +13,42 @@ What's New
     import xarray as xr
     np.random.seed(123456)
 
-.. _whats-new.0.12.4:
+.. _whats-new.0.13.0:
 
-v0.12.4 (unreleased)
--------------------
+v0.13.0 (unreleased)
+--------------------
 
 This release increases the minimum required Python version from 3.5.0 to 3.5.3
 (:issue:`3089`). By `Guido Imperiale <https://github.com/crusaderky>`_.
 
 New functions/methods
 ~~~~~~~~~~~~~~~~~~~~~
 
-- Added :py:meth:`DataArray.broadcast_like` and :py:meth:`Dataset.broadcast_like`.
-  By `Deepak Cherian <https://github.com/dcherian>`_ and `David Mertz 
-  <http://github.com/DavidMertz>`_.
+- xarray can now wrap around any
+  `NEP18 <https://www.numpy.org/neps/nep-0018-array-function-protocol.html>`_ compliant
+  numpy-like library (important: read notes about NUMPY_EXPERIMENTAL_ARRAY_FUNCTION in
+  the above link). Added explicit test coverage for
+  `sparse <https://github.com/pydata/sparse>`_. (:issue:`3117`, :issue:`3202`)
+  By `Nezar Abdennur <https://github.com/nvictus>`_
+  and `Guido Imperiale <https://github.com/crusaderky>`_.
 
-- The xarray package is now discoverably by mypy (although typing hints
-  coverage is not complete yet). mypy users can now remove from their setup.cfg
-  the lines::
+- The xarray package is now discoverable by mypy (although typing hints coverage is not
+  complete yet). mypy type checking is now enforced by CI. Libraries that depend on
+  xarray and use mypy can now remove from their setup.cfg the lines::
 
     [mypy-xarray]
     ignore_missing_imports = True
 
-   By `Guido Imperiale <https://github.com/crusaderky>`_
+  (:issue:`2877`, :issue:`3088`, :issue:`3090`, :issue:`3112`, :issue:`3117`,
+  :issue:`3207`)
+  By `Guido Imperiale <https://github.com/crusaderky>`_
+  and `Maximilian Roos <https://github.com/max-sixty>`_.
 
-- Dataset plotting API for visualizing dependences between two `DataArray`s!
+- Added :py:meth:`DataArray.broadcast_like` and :py:meth:`Dataset.broadcast_like`.
+  By `Deepak Cherian <https://github.com/dcherian>`_ and `David Mertz 
+  <http://github.com/DavidMertz>`_.
+
+- Dataset plotting API for visualizing dependencies between two `DataArray`s!
   Currently only :py:meth:`Dataset.plot.scatter` is implemented.
   By `Yohai Bar Sinai <https://github.com/yohai>`_ and `Deepak Cherian <https://github.com/dcherian>`_
 
@@ -62,6 +73,9 @@ Bug fixes
 - XFAIL several tests which are expected to fail on ARM systems
   due to a ``datetime`` issue in NumPy (:issue:`2334`).
   By `Graham Inggs <https://github.com/ginggs>`_.
+- Fix KeyError that arises when using .sel method with float values
+  different from coords float type (:issue:`3137`).
+  By `Hasan Ahmad <https://github.com/HasanAhmadQ7>`_.
 - Fixed bug in ``combine_by_coords()`` causing a `ValueError` if the input had
   an unused dimension with coordinates which were not monotonic (:issue:`3150`).
   By `Tom Nicholas <http://github.com/TomNicholas>`_.

xarray/core/common.py

@@ -46,12 +46,7 @@ def wrapped_func(self, dim=None, axis=None, skipna=None, **kwargs):
 
         else:
 
-            def wrapped_func(
-                self,
-                dim=None,
-                axis=None,  # type: ignore
-                **kwargs
-            ):
+            def wrapped_func(self, dim=None, axis=None, **kwargs):  # type: ignore
                 return self.reduce(func, dim, axis, allow_lazy=True, **kwargs)
 
         return wrapped_func