Fix compatibility with tabulate 0.10.0

Because `tabulate.PRESERVE_WHITESPACE` was replaced with a keyword
argument but was not removed from the module namespace (even though
modifying it no longer has any effect), the only way to check whether we
should pass the new `preserve_whitespace` argument is to examine
`tabulate.__version__`. This required adding a dependency on `packaging`
to parse and compare the version string.

Author: musicinmybrain

cli_helpers/tabular_output/tabulate_adapter.py

@@ -21,6 +21,7 @@
     escape_newlines,
 )
 
+from packaging.version import Version
 import tabulate
 
 
@@ -249,7 +250,10 @@ def adapter(data, headers, table_format=None, preserve_whitespace=False, **kwarg
     if table_format in supported_markup_formats:
         tkwargs.update(numalign=None, stralign=None)
 
-    tabulate.PRESERVE_WHITESPACE = preserve_whitespace
+    if Version(tabulate.__version__) < Version("0.10.0"):
+        tabulate.PRESERVE_WHITESPACE = preserve_whitespace
+    else:
+        tkwargs.update(preserve_whitespace=preserve_whitespace)
 
     tkwargs.update(default_kwargs.get(table_format, {}))
     if table_format in headless_formats:

setup.py

@@ -37,6 +37,7 @@ def open_file(filename):
     long_description_content_type="text/x-rst",
     install_requires=[
         "configobj >= 5.0.5",
+        "packaging",
         "tabulate[widechars] >= 0.9.0",
     ],
     extras_require={