From a73a78a167df7e9c0257e168dba2ffc65534becf Mon Sep 17 00:00:00 2001
From: "Martin K. Scherer" <m.scherer@fu-berlin.de>
Date: Thu, 7 Oct 2021 21:54:42 +0200
Subject: [PATCH] remove requirement for setuptools.pkg_resources

Fixes #5676

Now depends on importlib-metadata for Python major version < 3.8
---
 setup.cfg                      |  2 +-
 xarray/__init__.py             | 18 ++++++++++++++----
 xarray/backends/plugins.py     | 10 ++++++++--
 xarray/core/formatting_html.py | 14 ++++++++------
 4 files changed, 31 insertions(+), 13 deletions(-)

diff --git a/setup.cfg b/setup.cfg
index aa8ca8df0ff..4860704d77d 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -78,7 +78,7 @@ python_requires = >=3.7
 install_requires =
     numpy >= 1.17
     pandas >= 1.0
-    setuptools >= 40.4  # For pkg_resources
+    importlib-metadata; python_version < '3.8'
 
 [options.extras_require]
 io =
diff --git a/xarray/__init__.py b/xarray/__init__.py
index eb35bbb2d18..3a04bfa8631 100644
--- a/xarray/__init__.py
+++ b/xarray/__init__.py
@@ -1,5 +1,3 @@
-import pkg_resources
-
 from . import testing, tutorial, ufuncs
 from .backends.api import (
     load_dataarray,
@@ -28,13 +26,25 @@
 from .core.parallel import map_blocks
 from .core.variable import Coordinate, IndexVariable, Variable, as_variable
 from .util.print_versions import show_versions
-
 try:
-    __version__ = pkg_resources.get_distribution("xarray").version
+    try:
+        from importlib.metadata import version, PackageNotFoundError
+    except ImportError:
+        try:
+            from importlib_metadata import version, PackageNotFoundError
+        except ImportError:
+            raise
+
+    try:
+        __version__ = version("xarray")
+    except PackageNotFoundError:
+        raise
+    del version, PackageNotFoundError
 except Exception:
     # Local copy or not installed with setuptools.
     # Disable minimum version checks on downstream libraries.
     __version__ = "999"
+    raise
 
 # A hardcoded __all__ variable is necessary to appease
 # `mypy --strict` running in projects that import xarray.
diff --git a/xarray/backends/plugins.py b/xarray/backends/plugins.py
index 08c1bec8325..7e4894c00e1 100644
--- a/xarray/backends/plugins.py
+++ b/xarray/backends/plugins.py
@@ -95,8 +95,14 @@ def build_engines(pkg_entrypoints):
 
 @functools.lru_cache(maxsize=1)
 def list_engines():
-    pkg_entrypoints = pkg_resources.iter_entry_points("xarray.backends")
-    return build_engines(pkg_entrypoints)
+    try:
+        from importlib.metadata import Distribution
+    except ImportError:
+        from importlib_metadata import Distrubtion
+    importlib_entrypoints = (entry_point for entry_point
+                             in Distribution.from_name("xarray").entry_points
+                             if entry_point.module == "xarray.backends")
+    return build_engines(importlib_entrypoints)
 
 
 def guess_engine(store_spec):
diff --git a/xarray/core/formatting_html.py b/xarray/core/formatting_html.py
index 2a480427d4e..ad642ddd06b 100644
--- a/xarray/core/formatting_html.py
+++ b/xarray/core/formatting_html.py
@@ -3,8 +3,6 @@
 from functools import lru_cache, partial
 from html import escape
 
-import pkg_resources
-
 from .formatting import inline_variable_array_repr, short_data_repr
 from .options import _get_boolean_with_default
 
@@ -14,10 +12,14 @@
 @lru_cache(None)
 def _load_static_files():
     """Lazily load the resource files into memory the first time they are needed"""
-    return [
-        pkg_resources.resource_string("xarray", fname).decode("utf8")
-        for fname in STATIC_FILES
-    ]
+    import pathlib
+    parent = pathlib.Path(__file__).parent / "../"
+    result = []
+    for fname in STATIC_FILES:
+        with open(parent / fname) as fh:
+            result.append(fh.read().encode("utf8"))
+
+    return result
 
 
 def short_data_repr_html(array):