Merge pull request #44293 from UtahDave/fix_unittest_docs

Fix documentation grammar and spelling errors

doc/topics/development/tests/unit.rst

@@ -98,16 +98,16 @@ Mocking Loader Modules
 Salt loader modules use a series of globally available dunder variables,
 ``__salt__``, ``__opts__``, ``__pillar__``, etc. To facilitate testing these
 modules a mixin class was created, ``LoaderModuleMockMixin`` which can be found
-in ``tests/support/mixins.py``. The reason for the exitance of this class is 
+in ``tests/support/mixins.py``. The reason for the existance of this class is
-because, historycally, and because it was easier, one would add these dunder 
+because historiclly and because it was easier, one would add these dunder
 variables directly on the imported module. This however, introduces unexpected
 behavior when running the full test suite since those attributes would not be
-removed once we were done testing the module and would therefor leak to other 
+removed once we were done testing the module and would therefore leak to other
 modules being tested with unpredictable results. This is the kind of work that
-should be defered to mock, and that's exactly what this mixin class does.
+should be deferred to mock, and that's exactly what this mixin class does.
 
 As an example, if one needs to specify some options which should be available
-to the module being tests one should do:
+to the module being tested one should do:
 
 .. code-block:: python
 
@@ -173,10 +173,10 @@ Consider this more extensive example from
            return {libcloud_dns: module_globals}
 
 
-What happens on the above example is that, we mock a call to 
+What happens in the above example is we mock a call to
 `__salt__['config.option']` to return the configuration needed for the
 execution of the tests. Additionally, if the ``libcloud`` library is not
-available, since that's not actually part of whats being tested, we mocked that 
+available, since that's not actually part of what's being tested, we mocked that
 import by patching ``sys.modules`` when tests are running.
 
 
@@ -245,7 +245,7 @@ To understand how one might integrate Mock into writing a unit test for Salt,
 let's imagine a scenario in which we're testing an execution module that's
 designed to operate on a database. Furthermore, let's imagine two separate
 methods, here presented in pseduo-code in an imaginary execution module called
-'db.py.
+'db.py'.
 
 .. code-block:: python