Added a description to the pagination arguments.

Replicates graphql/graphql-relay-js@02a5a27

Author: Cito

Diff for: src/graphql_relay/connection/connection.py

@@ -37,15 +37,28 @@
 # Returns a GraphQLArgumentMap appropriate to include on a field
 # whose return type is a connection type with forward pagination.
 forward_connection_args: GraphQLArgumentMap = {
-    "after": GraphQLArgument(GraphQLString),
-    "first": GraphQLArgument(GraphQLInt),
+    "after": GraphQLArgument(
+        GraphQLString,
+        description="Returns the items in the list"
+        " that come after the specified cursor.",
+    ),
+    "first": GraphQLArgument(
+        GraphQLInt,
+        description="Returns the first n items from the list.",
+    ),
 }
 
 # Returns a GraphQLArgumentMap appropriate to include on a field
 # whose return type is a connection type with backward pagination.
 backward_connection_args: GraphQLArgumentMap = {
-    "before": GraphQLArgument(GraphQLString),
-    "last": GraphQLArgument(GraphQLInt),
+    "before": GraphQLArgument(
+        GraphQLString,
+        description="Returns the items in the list"
+        " that come before the specified cursor.",
+    ),
+    "last": GraphQLArgument(
+        GraphQLInt, description="Returns the last n items from the list."
+    ),
 }
 
 # Returns a GraphQLArgumentMap appropriate to include on a field

Diff for: tests/connection/test_connection.py

@@ -188,9 +188,33 @@ def generates_correct_types():
 
             type User {
               name: String
-              friends(after: String, first: Int, before: String, last: Int): FriendConnection
-              friendsForward(after: String, first: Int): UserConnection
-              friendsBackward(before: String, last: Int): UserConnection
+              friends(
+                """Returns the items in the list that come after the specified cursor."""
+                after: String
+
+                """Returns the first n items from the list."""
+                first: Int
+
+                """Returns the items in the list that come before the specified cursor."""
+                before: String
+
+                """Returns the last n items from the list."""
+                last: Int
+              ): FriendConnection
+              friendsForward(
+                """Returns the items in the list that come after the specified cursor."""
+                after: String
+
+                """Returns the first n items from the list."""
+                first: Int
+              ): UserConnection
+              friendsBackward(
+                """Returns the items in the list that come before the specified cursor."""
+                before: String
+
+                """Returns the last n items from the list."""
+                last: Int
+              ): UserConnection
             }
 
             """A connection to a list of items."""