swaps and moves

.depend

@@ -66,6 +66,16 @@ utils/diffing.cmx : \
     utils/diffing.cmi
 utils/diffing.cmi : \
     utils/misc.cmi
+utils/diffing_with_keys.cmo : \
+    utils/misc.cmi \
+    utils/diffing.cmi \
+    utils/diffing_with_keys.cmi
+utils/diffing_with_keys.cmx : \
+    utils/misc.cmx \
+    utils/diffing.cmx \
+    utils/diffing_with_keys.cmi
+utils/diffing_with_keys.cmi : \
+    utils/diffing.cmi
 utils/domainstate.cmo : \
     utils/domainstate.cmi
 utils/domainstate.cmx : \
@@ -695,6 +705,8 @@ typing/includecore.cmo : \
     typing/ident.cmi \
     typing/errortrace.cmi \
     typing/env.cmi \
+    utils/diffing_with_keys.cmi \
+    utils/diffing.cmi \
     typing/ctype.cmi \
     parsing/builtin_attributes.cmi \
     typing/btype.cmi \
@@ -710,6 +722,8 @@ typing/includecore.cmx : \
     typing/ident.cmx \
     typing/errortrace.cmx \
     typing/env.cmx \
+    utils/diffing_with_keys.cmx \
+    utils/diffing.cmx \
     typing/ctype.cmx \
     parsing/builtin_attributes.cmx \
     typing/btype.cmx \
@@ -723,7 +737,8 @@ typing/includecore.cmi : \
     parsing/location.cmi \
     typing/ident.cmi \
     typing/errortrace.cmi \
-    typing/env.cmi
+    typing/env.cmi \
+    utils/diffing_with_keys.cmi
 typing/includemod.cmo : \
     typing/types.cmi \
     typing/typedtree.cmi \

compilerlibs/Makefile.compilerlibs

@@ -45,7 +45,8 @@ UTILS = \
   utils/domainstate.cmo \
   utils/binutils.cmo \
   utils/lazy_backtrack.cmo \
-  utils/diffing.cmo
+  utils/diffing.cmo \
+  utils/diffing_with_keys.cmo
 UTILS_CMI =
 
 PARSING = \

dune

@@ -45,7 +45,7 @@
    config build_path_prefix_map misc identifiable numbers arg_helper clflags
    profile terminfo ccomp warnings consistbl strongly_connected_components
    targetint load_path int_replace_polymorphic_compare binutils local_store
-   lazy_backtrack diffing
+   lazy_backtrack diffing diffing_with_keys
 
    ;; PARSING
    location longident docstrings syntaxerr ast_helper camlinternalMenhirLib

testsuite/tests/typing-misc/records.ml

@@ -267,6 +267,5 @@ Line 1, characters 0-30:
 1 | type perm = d = {y:int; x:int}
     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 Error: This variant or record definition does not match that of type d
-       1. Fields have different names, x and y.
-       2. Fields have different names, y and x.
+       Fields x and y have been swapped.
 |}]

testsuite/tests/typing-misc/variant.ml

@@ -122,8 +122,7 @@ Line 1, characters 0-35:
 1 | type perm = d = Y of int | X of int
     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 Error: This variant or record definition does not match that of type d
-       1. Constructors have different names, X and Y.
-       2. Constructors have different names, Y and X.
+       Constructors X and Y have been swapped.
 |}]
 
 module M : sig

testsuite/tests/typing-modules/records_errors_test.ml

@@ -281,6 +281,218 @@ Error: Signature mismatch:
            g : unit;
          }
        3. An extra field, beta, is provided in the first declaration.
-       6. A field, e, is missing in the first declaration.
-       9. An extra field, phi, is provided in the first declaration.
+       5. A field, e, is missing in the first declaration.
+       8. An extra field, phi, is provided in the first declaration.
+|}]
+
+
+(** Multiple errors *)
+
+module M : sig
+  type t = { a:int; e:int; c:int; d:int; b:int }
+end = struct
+  type t = { alpha:int; b:int; c:int; d:int; e:int }
+end
+[%%expect {|
+Lines 5-7, characters 6-3:
+5 | ......struct
+6 |   type t = { alpha:int; b:int; c:int; d:int; e:int }
+7 | end
+Error: Signature mismatch:
+       Modules do not match:
+         sig
+           type t = { alpha : int; b : int; c : int; d : int; e : int; }
+         end
+       is not included in
+         sig type t = { a : int; e : int; c : int; d : int; b : int; } end
+       Type declarations do not match:
+         type t = { alpha : int; b : int; c : int; d : int; e : int; }
+       is not included in
+         type t = { a : int; e : int; c : int; d : int; b : int; }
+       1. Fields have different names, alpha and a.
+       2<->5. Fields b and e have been swapped.
+|}]
+
+
+module M: sig
+  type t = { a:int; b:int; c:int; d:int; e:int; f:float }
+end =
+struct
+  type t = { b:int; c:int; d:int; e:int; a:int; f:int }
+end
+[%%expect {|
+Lines 4-6, characters 0-3:
+4 | struct
+5 |   type t = { b:int; c:int; d:int; e:int; a:int; f:int }
+6 | end
+Error: Signature mismatch:
+       Modules do not match:
+         sig
+           type t = { b : int; c : int; d : int; e : int; a : int; f : int; }
+         end
+       is not included in
+         sig
+           type t = {
+             a : int;
+             b : int;
+             c : int;
+             d : int;
+             e : int;
+             f : float;
+           }
+         end
+       Type declarations do not match:
+         type t = { b : int; c : int; d : int; e : int; a : int; f : int; }
+       is not included in
+         type t = { a : int; b : int; c : int; d : int; e : int; f : float; }
+       1->5. Field a has been moved from position 1 to 5.
+       6. Fields do not match:
+         f : int;
+       is not compatible with:
+         f : float;
+       The types are not equal.
+|}]
+
+(** Existential types introduce equations that must be taken in account
+    when diffing
+*)
+
+
+module Eq : sig
+  type t = A: { a:'a; b:'b; x:'a } -> t
+end = struct
+  type t = A: { a:'a; b:'b; x:'x } -> t
+end
+[%%expect {|
+Lines 8-10, characters 6-3:
+ 8 | ......struct
+ 9 |   type t = A: { a:'a; b:'b; x:'x } -> t
+10 | end
+Error: Signature mismatch:
+       Modules do not match:
+         sig type t = A : { a : 'a; b : 'b; x : 'x; } -> t end
+       is not included in
+         sig type t = A : { a : 'a; b : 'b; x : 'a; } -> t end
+       Type declarations do not match:
+         type t = A : { a : 'a; b : 'b; x : 'x; } -> t
+       is not included in
+         type t = A : { a : 'a; b : 'b; x : 'a; } -> t
+       Constructors do not match:
+         A : { a : 'a; b : 'b; x : 'x; } -> t
+       is not compatible with:
+         A : { a : 'a; b : 'b; x : 'a; } -> t
+       Fields do not match:
+         x : 'x;
+       is not compatible with:
+         x : 'a;
+       The types are not equal.
+|}]
+
+
+module Not_a_swap: sig
+  type t = A: { x:'a; a:'a; b:'b; y:'b} -> t
+end = struct
+  type t = A: { y:'a; a:'a; b:'b; x:'b} -> t
+end
+[%%expect {|
+Lines 3-5, characters 6-3:
+3 | ......struct
+4 |   type t = A: { y:'a; a:'a; b:'b; x:'b} -> t
+5 | end
+Error: Signature mismatch:
+       Modules do not match:
+         sig type t = A : { y : 'a; a : 'a; b : 'b; x : 'b; } -> t end
+       is not included in
+         sig type t = A : { x : 'a; a : 'a; b : 'b; y : 'b; } -> t end
+       Type declarations do not match:
+         type t = A : { y : 'a; a : 'a; b : 'b; x : 'b; } -> t
+       is not included in
+         type t = A : { x : 'a; a : 'a; b : 'b; y : 'b; } -> t
+       Constructors do not match:
+         A : { y : 'a; a : 'a; b : 'b; x : 'b; } -> t
+       is not compatible with:
+         A : { x : 'a; a : 'a; b : 'b; y : 'b; } -> t
+       1. Fields have different names, y and x.
+       4. Fields have different names, x and y.
+|}]
+
+module Swap: sig
+  type t = A: { x:'a; a:'a; b:'b; y:'b} -> t
+end = struct
+  type t = A: { y:'b; a:'a; b:'b; x:'a} -> t
+end
+[%%expect {|
+Lines 3-5, characters 6-3:
+3 | ......struct
+4 |   type t = A: { y:'b; a:'a; b:'b; x:'a} -> t
+5 | end
+Error: Signature mismatch:
+       Modules do not match:
+         sig type t = A : { y : 'b; a : 'a; b : 'b; x : 'a; } -> t end
+       is not included in
+         sig type t = A : { x : 'a; a : 'a; b : 'b; y : 'b; } -> t end
+       Type declarations do not match:
+         type t = A : { y : 'b; a : 'a; b : 'b; x : 'a; } -> t
+       is not included in
+         type t = A : { x : 'a; a : 'a; b : 'b; y : 'b; } -> t
+       Constructors do not match:
+         A : { y : 'b; a : 'a; b : 'b; x : 'a; } -> t
+       is not compatible with:
+         A : { x : 'a; a : 'a; b : 'b; y : 'b; } -> t
+       Fields x and y have been swapped.
+|}]
+
+
+module Not_a_move: sig
+  type t = A: { a:'a; b:'b; x:'b} -> t
+end = struct
+  type t = A: { x:'a; a:'a; b:'b} -> t
+end
+[%%expect {|
+Lines 3-5, characters 6-3:
+3 | ......struct
+4 |   type t = A: { x:'a; a:'a; b:'b} -> t
+5 | end
+Error: Signature mismatch:
+       Modules do not match:
+         sig type t = A : { x : 'a; a : 'a; b : 'b; } -> t end
+       is not included in
+         sig type t = A : { a : 'a; b : 'b; x : 'b; } -> t end
+       Type declarations do not match:
+         type t = A : { x : 'a; a : 'a; b : 'b; } -> t
+       is not included in
+         type t = A : { a : 'a; b : 'b; x : 'b; } -> t
+       Constructors do not match:
+         A : { x : 'a; a : 'a; b : 'b; } -> t
+       is not compatible with:
+         A : { a : 'a; b : 'b; x : 'b; } -> t
+       1. An extra field, x, is provided in the first declaration.
+       3. A field, x, is missing in the first declaration.
+|}]
+
+
+module Move: sig
+  type t = A: { a:'a; b:'b; x:'b} -> t
+end = struct
+  type t = A: { x:'b; a:'a; b:'b} -> t
+end
+[%%expect {|
+Lines 3-5, characters 6-3:
+3 | ......struct
+4 |   type t = A: { x:'b; a:'a; b:'b} -> t
+5 | end
+Error: Signature mismatch:
+       Modules do not match:
+         sig type t = A : { x : 'b; a : 'a; b : 'b; } -> t end
+       is not included in
+         sig type t = A : { a : 'a; b : 'b; x : 'b; } -> t end
+       Type declarations do not match:
+         type t = A : { x : 'b; a : 'a; b : 'b; } -> t
+       is not included in
+         type t = A : { a : 'a; b : 'b; x : 'b; } -> t
+       Constructors do not match:
+         A : { x : 'b; a : 'a; b : 'b; } -> t
+       is not compatible with:
+         A : { a : 'a; b : 'b; x : 'b; } -> t
+       Field x has been moved from position 3 to 1.
 |}]

testsuite/tests/typing-modules/variants_errors_test.ml

@@ -320,6 +320,93 @@ Error: Signature mismatch:
        is not included in
          type t = A | B | C | D | E | F | G
        3. An extra constructor, Beta, is provided in the first declaration.
-       6. A constructor, E, is missing in the first declaration.
-       9. An extra constructor, Phi, is provided in the first declaration.
+       5. A constructor, E, is missing in the first declaration.
+       8. An extra constructor, Phi, is provided in the first declaration.
+|}]
+
+
+(** Swaps and moves *)
+
+module Swap : sig
+  type t =
+    | A
+    | E
+    | C
+    | D
+    | B
+end = struct
+  type t =
+    | Alpha
+    | B
+    | C
+    | D
+    | E
+end
+[%%expect {|
+Lines 10-17, characters 6-3:
+10 | ......struct
+11 |   type t =
+12 |     | Alpha
+13 |     | B
+14 |     | C
+15 |     | D
+16 |     | E
+17 | end
+Error: Signature mismatch:
+       Modules do not match:
+         sig type t = Alpha | B | C | D | E end
+       is not included in
+         sig type t = A | E | C | D | B end
+       Type declarations do not match:
+         type t = Alpha | B | C | D | E
+       is not included in
+         type t = A | E | C | D | B
+       1. Constructors have different names, Alpha and A.
+       2<->5. Constructors B and E have been swapped.
+|}]
+
+
+module Move: sig
+  type t =
+    | A of int
+    | B
+    | C
+    | D
+    | E
+    | F
+end = struct
+  type t =
+    | A of float
+    | B
+    | D
+    | E
+    | F
+    | C
+end
+[%%expect {|
+Lines 9-17, characters 6-3:
+ 9 | ......struct
+10 |   type t =
+11 |     | A of float
+12 |     | B
+13 |     | D
+14 |     | E
+15 |     | F
+16 |     | C
+17 | end
+Error: Signature mismatch:
+       Modules do not match:
+         sig type t = A of float | B | D | E | F | C end
+       is not included in
+         sig type t = A of int | B | C | D | E | F end
+       Type declarations do not match:
+         type t = A of float | B | D | E | F | C
+       is not included in
+         type t = A of int | B | C | D | E | F
+       1. Constructors do not match:
+         A of float
+       is not compatible with:
+         A of int
+       The types are not equal.
+       3->6. Constructor C has been moved from position 3 to 6.
 |}]