Changed error message for invalid type parameters to include Subtract

Summary:
+ Problem: The error message for failing to give arithmetic type operators types that are a subtype of int does not include `Subtract`.
+ Background: In the previous diff, we implemented the `Subtract` type operator. When it fails (and is given arguments that are not a subtype of int), a particular error message displays, which is hard-coded to include `Add`, `Multiply`, and `Divide`, but not `Subtract`.
+ Solution: This diff just makes `Subtract` included in that message.

Reviewed By: pradeep90

Differential Revision: D30049950

fbshipit-source-id: d4b17b32d83428a02f36094cff73e87365d37b12

source/analysis/analysisError.ml

@@ -1255,8 +1255,9 @@ let rec messages ~concise ~signature location kind =
       [
         Format.asprintf
           "Type parameter `%a` violates constraints on \
-           `pyre_extensions.Add`/`pyre_extensions.Multiply`/`pyre_extensions.Divide`. Add & \
-           Multiply & Divide only accept type variables with a bound that's a subtype of int."
+           `pyre_extensions.Add`/`pyre_extensions.Multiply`/`pyre_extensions.Subtract`/`pyre_extensions.Divide`. \
+           Add & Multiply & Subtract & Divide only accept type variables with a bound that's a \
+           subtype of int."
           pp_type
           actual;
       ]

source/analysis/test/integration/annotationTest.ml

@@ -1853,14 +1853,17 @@ let test_check_typevar_arithmetic context =
     |}
     [
       "Invalid type parameters [24]: Type parameter `Variable[A]` violates constraints on \
-       `pyre_extensions.Add`/`pyre_extensions.Multiply`/`pyre_extensions.Divide`. Add & Multiply & \
-       Divide only accept type variables with a bound that's a subtype of int.";
+       `pyre_extensions.Add`/`pyre_extensions.Multiply`/`pyre_extensions.Subtract`/`pyre_extensions.Divide`. \
+       Add & Multiply & Subtract & Divide only accept type variables with a bound that's a subtype \
+       of int.";
       "Invalid type parameters [24]: Type parameter `Variable[A]` violates constraints on \
-       `pyre_extensions.Add`/`pyre_extensions.Multiply`/`pyre_extensions.Divide`. Add & Multiply & \
-       Divide only accept type variables with a bound that's a subtype of int.";
+       `pyre_extensions.Add`/`pyre_extensions.Multiply`/`pyre_extensions.Subtract`/`pyre_extensions.Divide`. \
+       Add & Multiply & Subtract & Divide only accept type variables with a bound that's a subtype \
+       of int.";
       "Invalid type parameters [24]: Type parameter `Variable[A]` violates constraints on \
-       `pyre_extensions.Add`/`pyre_extensions.Multiply`/`pyre_extensions.Divide`. Add & Multiply & \
-       Divide only accept type variables with a bound that's a subtype of int.";
+       `pyre_extensions.Add`/`pyre_extensions.Multiply`/`pyre_extensions.Subtract`/`pyre_extensions.Divide`. \
+       Add & Multiply & Subtract & Divide only accept type variables with a bound that's a subtype \
+       of int.";
     ];
   assert_type_errors
     {|
@@ -3424,8 +3427,9 @@ let test_check_subtract context =
     |}
     [
       "Invalid type parameters [24]: Type parameter `Variable[A]` violates constraints on \
-       `pyre_extensions.Add`/`pyre_extensions.Multiply`/`pyre_extensions.Divide`. Add & Multiply & \
-       Divide only accept type variables with a bound that's a subtype of int.";
+       `pyre_extensions.Add`/`pyre_extensions.Multiply`/`pyre_extensions.Subtract`/`pyre_extensions.Divide`. \
+       Add & Multiply & Subtract & Divide only accept type variables with a bound that's a subtype \
+       of int.";
     ];
   assert_default_type_errors
     {|