Add new test cases for module inclusion errors

These test cases will have improved error messages in the next commit

testsuite/tests/typing-misc/deep.ml

@@ -0,0 +1,88 @@
+(* TEST
+   * expect
+*)
+
+module M : sig
+  val x : bool * int
+end = struct
+  let x = false , "not an int"
+end
+[%%expect{|
+Lines 3-5, characters 6-3:
+3 | ......struct
+4 |   let x = false , "not an int"
+5 | end
+Error: Signature mismatch:
+       Modules do not match:
+         sig val x : bool * string end
+       is not included in
+         sig val x : bool * int end
+       Values do not match:
+         val x : bool * string
+       is not included in
+         val x : bool * int
+|}]
+
+module T : sig
+  val f : int -> (float * string ref) list
+end = struct
+  let f x = x + List.length [0.0, ref true]
+end
+[%%expect{|
+Lines 3-5, characters 6-3:
+3 | ......struct
+4 |   let f x = x + List.length [0.0, ref true]
+5 | end
+Error: Signature mismatch:
+       Modules do not match:
+         sig val f : int -> int end
+       is not included in
+         sig val f : int -> (float * string ref) list end
+       Values do not match:
+         val f : int -> int
+       is not included in
+         val f : int -> (float * string ref) list
+|}]
+
+(* Alpha-equivalence *)
+module T : sig
+  val f : ('a list * 'b list -> int)
+end = struct
+  let f : ('c list * 'd ref  -> int) = assert false
+end
+[%%expect{|
+Lines 3-5, characters 6-3:
+3 | ......struct
+4 |   let f : ('c list * 'd ref  -> int) = assert false
+5 | end
+Error: Signature mismatch:
+       Modules do not match:
+         sig val f : 'c list * 'd ref -> int end
+       is not included in
+         sig val f : 'a list * 'b list -> int end
+       Values do not match:
+         val f : 'c list * 'd ref -> int
+       is not included in
+         val f : 'a list * 'b list -> int
+|}]
+
+module T : sig
+  type t = int * float
+end = struct
+  type t = bool * float
+end
+[%%expect{|
+Lines 3-5, characters 6-3:
+3 | ......struct
+4 |   type t = bool * float
+5 | end
+Error: Signature mismatch:
+       Modules do not match:
+         sig type t = bool * float end
+       is not included in
+         sig type t = int * float end
+       Type declarations do not match:
+         type t = bool * float
+       is not included in
+         type t = int * float
+|}]

testsuite/tests/typing-modules/inclusion_errors.ml

@@ -1053,6 +1053,70 @@ Error: Signature mismatch:
          type t = private [> `A of int ]
 |}];;
 
+module M : sig
+  type t = private [< `A | `B]
+end = struct
+  type t = private [`A | `B]
+end;;
+[%%expect{|
+Lines 3-5, characters 6-3:
+3 | ......struct
+4 |   type t = private [`A | `B]
+5 | end..
+Error: Signature mismatch:
+       Modules do not match:
+         sig type t = private [ `A | `B ] end
+       is not included in
+         sig type t = private [< `A | `B ] end
+       Type declarations do not match:
+         type t = private [ `A | `B ]
+       is not included in
+         type t = private [< `A | `B ]
+|}];;
+
+module M : sig
+  type t = [`A | `B]
+end = struct
+  type t = private [`A | `B]
+end;;
+[%%expect{|
+Lines 3-5, characters 6-3:
+3 | ......struct
+4 |   type t = private [`A | `B]
+5 | end..
+Error: Signature mismatch:
+       Modules do not match:
+         sig type t = private [ `A | `B ] end
+       is not included in
+         sig type t = [ `A | `B ] end
+       Type declarations do not match:
+         type t = private [ `A | `B ]
+       is not included in
+         type t = [ `A | `B ]
+       A private type would be revealed.
+|}];;
+
+module M : sig
+  type t = private [< `A | `B > `B]
+end = struct
+  type t = private [< `A | `B]
+end;;
+[%%expect{|
+Lines 3-5, characters 6-3:
+3 | ......struct
+4 |   type t = private [< `A | `B]
+5 | end..
+Error: Signature mismatch:
+       Modules do not match:
+         sig type t = private [< `A | `B ] end
+       is not included in
+         sig type t = private [< `A | `B > `B ] end
+       Type declarations do not match:
+         type t = private [< `A | `B ]
+       is not included in
+         type t = private [< `A | `B > `B ]
+|}];;
+
 module M : sig
   type t = private <a : int; ..>
 end = struct

testsuite/tests/typing-modules/pr10399.ml

@@ -0,0 +1,44 @@
+(* TEST
+ * expect
+*)
+
+(* From jctis: <https://github.com/ocaml/ocaml/issues/10399> *)
+
+module PR10399 : sig
+  type t = < x : int >
+
+  class c : object method x : int method y : bool end
+
+  val o : t
+end = struct
+  type t = < x : int >
+
+  class c = object method x = 3 method y = true end
+
+  let o = new c
+end
+
+[%%expect{|
+Lines 7-13, characters 6-3:
+ 7 | ......struct
+ 8 |   type t = < x : int >
+ 9 |
+10 |   class c = object method x = 3 method y = true end
+11 |
+12 |   let o = new c
+13 | end
+Error: Signature mismatch:
+       Modules do not match:
+         sig
+           type t = < x : int >
+           class c : object method x : int method y : bool end
+           val o : c
+         end
+       is not included in
+         sig
+           type t = < x : int >
+           class c : object method x : int method y : bool end
+           val o : t
+         end
+       Values do not match: val o : c is not included in val o : t
+|}]