Improve choice rule documentation

Author: Daniel Yoo

src/stepfunctions/steps/choice_rule.py

@@ -613,7 +613,7 @@ def IsNull(cls, variable, value):
 
         Args:
             variable (str): Path to the variable to compare.
-            value (bool): Whether the value at variable is equal to the JSON literal null or not.
+            value (bool): Whether the value at `variable` is equal to the JSON literal null or not.
 
         Returns:
             Rule: Rule with `IsNull` operator.
@@ -627,7 +627,7 @@ def IsPresent(cls, variable, value):
 
         Args:
             variable (str): Path to the variable to compare.
-            value (bool): Whether a field at variable exists in the input or not.
+            value (bool): Whether a field at `variable` exists in the input or not.
 
         Returns:
             Rule: Rule with `IsPresent` operator.
@@ -641,7 +641,7 @@ def IsString(cls, variable, value):
 
         Args:
             variable (str): Path to the variable to compare.
-            value (bool): Whether the value at variable is a string or not.
+            value (bool): Whether the value at `variable` is a string or not.
 
         Returns:
             Rule: Rule with `IsString` operator.
@@ -655,7 +655,7 @@ def IsNumeric(cls, variable, value):
 
         Args:
             variable (str): Path to the variable to compare.
-            value (bool): Whether the value at variable is a number or not.
+            value (bool): Whether the value at `variable` is a number or not.
 
         Returns:
             Rule: Rule with `IsNumeric` operator.
@@ -669,7 +669,7 @@ def IsTimestamp(cls, variable, value):
 
         Args:
             variable (str): Path to the variable to compare.
-            value (bool): Whether the value at variable is a timestamp or not.
+            value (bool): Whether the value at `variable` is a timestamp or not.
 
         Returns:
             Rule: Rule with `IsTimestamp` operator.
@@ -683,7 +683,7 @@ def IsBoolean(cls, variable, value):
 
         Args:
             variable (str): Path to the variable to compare.
-            value (bool): Whether the value at variable is a boolean or not.
+            value (bool): Whether the value at `variable` is a boolean or not.
 
         Returns:
             Rule: Rule with `IsBoolean` operator.
@@ -697,7 +697,9 @@ def StringMatches(cls, variable, value):
 
         Args:
             variable (str): Path to the variable to compare.
-            value (bool): Constant value to compare `variable` against.
+            value (str): A string pattern that may contain one or more `*` characters to compare the value at `variable` to.
+                The `*` character can be escaped using two backslashes.
+                The comparison yields true if the variable matches the pattern, where `*` is a wildcard that matches zero or more characters.
 
         Returns:
             Rule: Rule with `StringMatches` operator.

tests/unit/test_choice_rule.py

@@ -61,20 +61,20 @@ def test_variable_value_must_be_consistent():
         with pytest.raises(ValueError):
             func('$.Variable', True)
 
-def test_path_function_value_must_be_consistent():
-    path_functions = {
+def test_path_comparator_raises_error_when_value_is_not_a_path():
+    path_comparators = {
         'StringEqualsPath',
         'NumericEqualsPath',
         'TimestampEqualsPath',
         'BooleanEqualsPath'
     }
-    for path_function in path_functions:
-        func = getattr(ChoiceRule, path_function)
+    for path_comparator in path_comparators:
+        func = getattr(ChoiceRule, path_comparator)
         with pytest.raises(ValueError):
             func('$.Variable', 'string')
 
-def test_is_function_value_must_be_consistent():
-    type_functions = {
+def test_is_comparator_raises_error_when_value_is_not_a_bool():
+    type_comparators = {
         'IsPresent',
         'IsNull',
         'IsString',
@@ -83,14 +83,13 @@ def test_is_function_value_must_be_consistent():
         'IsTimestamp'
     }
 
-    for type_function in type_functions:
-        func = getattr(ChoiceRule, type_function)
+    for type_comparator in type_comparators:
+        func = getattr(ChoiceRule, type_comparator)
         with pytest.raises(ValueError):
             func('$.Variable', 'string')
         with pytest.raises(ValueError):
             func('$.Variable', 101)
 
-# tox -e py37 -- -s -vv tests/unit/test_choice_rule.py::test_dynamic_comparator_serialization
 def test_static_comparator_serialization():
     string_timestamp_static_comparators = {
         'StringEquals',