Addressing more reviewer comments. This revamps the generation of err…

…or messages, removing some older broken heuristics and trying to fix the problem of orientation of 'expected' vs 'found' at the core. Some context annotation 'from assignment context' not tries to clarify the error message if the typing error is for an lvalue, where the expected type is a _lower bound_ instead of an upper bound, which may leads to confusion for end users. The messages are now more systematic but perhaps a bit harder to understand, yet this is not trivial to fix and we have to iterate on this.

third_party/move/move-compiler-v2/tests/checking/naming/generics_shadowing_invalid.exp

@@ -13,10 +13,10 @@ error: expected `S` but found `M::S`
   │                    ^^^^
 
 error: invalid call of `M::bar`: expected `M::S` but found `S` for argument 1
-  ┌─ tests/checking/naming/generics_shadowing_invalid.move:9:9
+  ┌─ tests/checking/naming/generics_shadowing_invalid.move:9:13
   │
 9 │         bar(s1);
-  │         ^^^^^^^
+  │             ^^
 
 error: expected `S` but found `M::S`
    ┌─ tests/checking/naming/generics_shadowing_invalid.move:10:9

third_party/move/move-compiler-v2/tests/checking/typing/assign_unpack_references_invalid.exp

@@ -1,36 +1,36 @@
 
 Diagnostics:
-error: expected `&u64` but found `integer`
-  ┌─ tests/checking/typing/assign_unpack_references_invalid.move:9:13
+error: expected `&u64` but found `integer` (from assignment or declaration context)
+  ┌─ tests/checking/typing/assign_unpack_references_invalid.move:9:9
   │
 9 │         f = 0;
-  │             ^
+  │         ^
 
-error: expected `&M::S` but found `M::S`
+error: expected `&M::S` but found `M::S` (from assignment or declaration context)
    ┌─ tests/checking/typing/assign_unpack_references_invalid.move:10:9
    │
 10 │         s2 = S { f: 0 }
    │         ^^
 
-error: expected `&mut u64` but found `integer`
-   ┌─ tests/checking/typing/assign_unpack_references_invalid.move:17:13
+error: expected `&mut u64` but found `integer` (from assignment or declaration context)
+   ┌─ tests/checking/typing/assign_unpack_references_invalid.move:17:9
    │
 17 │         f = 0;
-   │             ^
+   │         ^
 
-error: expected `&mut M::S` but found `M::S`
+error: expected `&mut M::S` but found `M::S` (from assignment or declaration context)
    ┌─ tests/checking/typing/assign_unpack_references_invalid.move:18:9
    │
 18 │         s2 = S { f: 0 }
    │         ^^
 
-error: mutability mismatch (&mut != &)
+error: mutability mismatch (&mut != &) (from assignment or declaration context)
    ┌─ tests/checking/typing/assign_unpack_references_invalid.move:26:9
    │
 26 │         f = &0;
    │         ^
 
-error: mutability mismatch (&mut != &)
+error: mutability mismatch (&mut != &) (from assignment or declaration context)
    ┌─ tests/checking/typing/assign_unpack_references_invalid.move:27:9
    │
 27 │         s2 = &S { f: 0 }

third_party/move/move-compiler-v2/tests/checking/typing/assign_wrong_arity.exp

@@ -1,16 +1,16 @@
 
 Diagnostics:
-error: tuples have different arity (0 != 3)
+error: tuples have different arity (0 != 3) (from assignment or declaration context)
   ┌─ tests/checking/typing/assign_wrong_arity.move:7:9
   │
 7 │         x = (0, 1, 2);
   │         ^
 
-error: expected `()` but found `integer`
-  ┌─ tests/checking/typing/assign_wrong_arity.move:8:14
+error: expected `()` but found `integer` (from assignment or declaration context)
+  ┌─ tests/checking/typing/assign_wrong_arity.move:8:9
   │
 8 │         () = 0;
-  │              ^
+  │         ^^
 
 error: expected 4 item(s), found 3
    ┌─ tests/checking/typing/assign_wrong_arity.move:11:9

third_party/move/move-compiler-v2/tests/checking/typing/assign_wrong_type.exp

@@ -12,11 +12,11 @@ error: expected `M::S` but found `M::R`
 9 │         (S { g }, R { f }) = (R{ f: 0 }, R{ f: 1 });
   │          ^^^^^^^
 
-error: expected `()` but found `integer`
-   ┌─ tests/checking/typing/assign_wrong_type.move:17:14
+error: expected `()` but found `integer` (from assignment or declaration context)
+   ┌─ tests/checking/typing/assign_wrong_type.move:17:9
    │
 17 │         () = 0;
-   │              ^
+   │         ^^
 
 error: expected 4 item(s), found 3
    ┌─ tests/checking/typing/assign_wrong_type.move:18:9
@@ -30,25 +30,25 @@ error: expected 2 item(s), found 3
 19 │         (x, b, R{f}) = (0, false);
    │         ^^^^^^^^^^^^
 
-error: expected `bool` but found `integer`
-   ┌─ tests/checking/typing/assign_wrong_type.move:27:28
+error: expected `bool` but found `integer` (from assignment or declaration context)
+   ┌─ tests/checking/typing/assign_wrong_type.move:27:10
    │
 27 │         (x, b, R{f}, r) = (0, false, R{f: 0}, R{f: 0});
-   │                            ^
+   │          ^
 
-error: expected `bool` but found `integer`
-   ┌─ tests/checking/typing/assign_wrong_type.move:24:17
+error: expected `integer` but found `bool` (from assignment or declaration context)
+   ┌─ tests/checking/typing/assign_wrong_type.move:27:13
    │
-24 │         let b = 0;
-   │                 ^
+27 │         (x, b, R{f}, r) = (0, false, R{f: 0}, R{f: 0});
+   │             ^
 
-error: expected `address` but found `u64`
+error: expected `address` but found `u64` (from assignment or declaration context)
    ┌─ tests/checking/typing/assign_wrong_type.move:27:18
    │
 27 │         (x, b, R{f}, r) = (0, false, R{f: 0}, R{f: 0});
    │                  ^
 
-error: expected `M::S` but found `M::R`
+error: expected `M::S` but found `M::R` (from assignment or declaration context)
    ┌─ tests/checking/typing/assign_wrong_type.move:27:22
    │
 27 │         (x, b, R{f}, r) = (0, false, R{f: 0}, R{f: 0});

third_party/move/move-compiler-v2/tests/checking/typing/binary_add_invalid.exp

@@ -4,76 +4,76 @@ error: invalid call of `+`: expected `integer` but found `bool` for argument 1
   ┌─ tests/checking/typing/binary_add_invalid.move:8:9
   │
 8 │         false + true;
-  │         ^^^^^^^^^^^^
+  │         ^^^^^
 
 error: invalid call of `+`: expected `integer` but found `bool` for argument 2
-  ┌─ tests/checking/typing/binary_add_invalid.move:9:9
+  ┌─ tests/checking/typing/binary_add_invalid.move:9:13
   │
 9 │         1 + false;
-  │         ^^^^^^^^^
+  │             ^^^^^
 
 error: invalid call of `+`: expected `integer` but found `bool` for argument 1
    ┌─ tests/checking/typing/binary_add_invalid.move:10:9
    │
 10 │         false + 1;
-   │         ^^^^^^^^^
+   │         ^^^^^
 
 error: invalid call of `+`: expected `integer` but found `address` for argument 1
    ┌─ tests/checking/typing/binary_add_invalid.move:11:9
    │
 11 │         @0x0 + @0x1;
-   │         ^^^^^^^^^^^
+   │         ^^^^
 
 error: invalid call of `+`: expected `u8` but found `u128` for argument 2
-   ┌─ tests/checking/typing/binary_add_invalid.move:12:9
+   ┌─ tests/checking/typing/binary_add_invalid.move:12:20
    │
 12 │         (0: u8) + (1: u128);
-   │         ^^^^^^^^^^^^^^^^^^^
+   │                    ^
 
 error: invalid call of `+`: expected `integer` but found `M::R` for argument 1
    ┌─ tests/checking/typing/binary_add_invalid.move:13:9
    │
 13 │         r + r;
-   │         ^^^^^
+   │         ^
 
 error: invalid call of `+`: expected `integer` but found `M::S` for argument 1
    ┌─ tests/checking/typing/binary_add_invalid.move:14:9
    │
 14 │         s + s;
-   │         ^^^^^
+   │         ^
 
 error: invalid call of `+`: expected `integer` but found `bool` for argument 2
-   ┌─ tests/checking/typing/binary_add_invalid.move:15:9
+   ┌─ tests/checking/typing/binary_add_invalid.move:15:13
    │
 15 │         1 + false + @0x0 + 0;
-   │         ^^^^^^^^^
+   │             ^^^^^
 
 error: invalid call of `+`: expected `integer` but found `address` for argument 2
-   ┌─ tests/checking/typing/binary_add_invalid.move:15:9
+   ┌─ tests/checking/typing/binary_add_invalid.move:15:21
    │
 15 │         1 + false + @0x0 + 0;
-   │         ^^^^^^^^^^^^^^^^
+   │                     ^^^^
 
 error: invalid call of `+`: expected `integer` but found `()` for argument 1
    ┌─ tests/checking/typing/binary_add_invalid.move:16:9
    │
 16 │         () + ();
-   │         ^^^^^^^
+   │         ^^
 
 error: invalid call of `+`: expected `integer` but found `()` for argument 2
-   ┌─ tests/checking/typing/binary_add_invalid.move:17:9
+   ┌─ tests/checking/typing/binary_add_invalid.move:17:13
    │
 17 │         1 + ();
-   │         ^^^^^^
+   │             ^^
 
 error: invalid call of `+`: expected `integer` but found `(integer, integer)` for argument 1
    ┌─ tests/checking/typing/binary_add_invalid.move:18:9
    │
 18 │         (0, 1) + (0, 1, 2);
-   │         ^^^^^^^^^^^^^^^^^^
+   │         ^^^^^^
 
 error: invalid call of `+`: expected `integer` but found `(integer, integer)` for argument 1
    ┌─ tests/checking/typing/binary_add_invalid.move:19:9
    │
 19 │         (1, 2) + (0, 1);
-   │         ^^^^^^^^^^^^^^^
+   │         ^^^^^^

third_party/move/move-compiler-v2/tests/checking/typing/binary_and_invalid.exp

@@ -22,46 +22,46 @@ error: invalid call of `&&`: expected `bool` but found `address` for argument 1
    ┌─ tests/checking/typing/binary_and_invalid.move:11:9
    │
 11 │         @0x0 && @0x1;
-   │         ^^^^^^^^^^^^
+   │         ^^^^
 
 error: invalid call of `&&`: expected `bool` but found `u8` for argument 1
-   ┌─ tests/checking/typing/binary_and_invalid.move:12:9
+   ┌─ tests/checking/typing/binary_and_invalid.move:12:10
    │
 12 │         (0: u8) && (1: u128);
-   │         ^^^^^^^^^^^^^^^^^^^^
+   │          ^
 
 error: invalid call of `&&`: expected `bool` but found `M::R` for argument 1
    ┌─ tests/checking/typing/binary_and_invalid.move:13:9
    │
 13 │         r && r;
-   │         ^^^^^^
+   │         ^
 
 error: invalid call of `&&`: expected `bool` but found `M::S` for argument 1
    ┌─ tests/checking/typing/binary_and_invalid.move:14:9
    │
 14 │         s && s;
-   │         ^^^^^^
+   │         ^
 
 error: invalid call of `&&`: expected `bool` but found `()` for argument 1
    ┌─ tests/checking/typing/binary_and_invalid.move:15:9
    │
 15 │         () && ();
-   │         ^^^^^^^^
+   │         ^^
 
 error: invalid call of `&&`: expected `bool` but found `()` for argument 2
-   ┌─ tests/checking/typing/binary_and_invalid.move:16:9
+   ┌─ tests/checking/typing/binary_and_invalid.move:16:17
    │
 16 │         true && ();
-   │         ^^^^^^^^^^
+   │                 ^^
 
 error: invalid call of `&&`: expected `bool` but found `(bool, bool)` for argument 1
    ┌─ tests/checking/typing/binary_and_invalid.move:17:9
    │
 17 │         (true, false) && (true, false, true);
-   │         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   │         ^^^^^^^^^^^^^
 
 error: invalid call of `&&`: expected `bool` but found `(bool, bool)` for argument 1
    ┌─ tests/checking/typing/binary_and_invalid.move:18:9
    │
 18 │         (true, true) && (false, false);
-   │         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+   │         ^^^^^^^^^^^^

third_party/move/move-compiler-v2/tests/checking/typing/binary_bit_and_invalid.exp

@@ -4,76 +4,76 @@ error: invalid call of `&`: expected `integer` but found `bool` for argument 1
   ┌─ tests/checking/typing/binary_bit_and_invalid.move:8:9
   │
 8 │         false & true;
-  │         ^^^^^^^^^^^^
+  │         ^^^^^
 
 error: invalid call of `&`: expected `integer` but found `bool` for argument 2
-  ┌─ tests/checking/typing/binary_bit_and_invalid.move:9:9
+  ┌─ tests/checking/typing/binary_bit_and_invalid.move:9:13
   │
 9 │         1 & false;
-  │         ^^^^^^^^^
+  │             ^^^^^
 
 error: invalid call of `&`: expected `integer` but found `bool` for argument 1
    ┌─ tests/checking/typing/binary_bit_and_invalid.move:10:9
    │
 10 │         false & 1;
-   │         ^^^^^^^^^
+   │         ^^^^^
 
 error: invalid call of `&`: expected `integer` but found `address` for argument 1
    ┌─ tests/checking/typing/binary_bit_and_invalid.move:11:9
    │
 11 │         @0x0 & @0x1;
-   │         ^^^^^^^^^^^
+   │         ^^^^
 
 error: invalid call of `&`: expected `u8` but found `u128` for argument 2
-   ┌─ tests/checking/typing/binary_bit_and_invalid.move:12:9
+   ┌─ tests/checking/typing/binary_bit_and_invalid.move:12:20
    │
 12 │         (0: u8) & (1: u128);
-   │         ^^^^^^^^^^^^^^^^^^^
+   │                    ^
 
 error: invalid call of `&`: expected `integer` but found `M::R` for argument 1
    ┌─ tests/checking/typing/binary_bit_and_invalid.move:13:9
    │
 13 │         r & r;
-   │         ^^^^^
+   │         ^
 
 error: invalid call of `&`: expected `integer` but found `M::S` for argument 1
    ┌─ tests/checking/typing/binary_bit_and_invalid.move:14:9
    │
 14 │         s & s;
-   │         ^^^^^
+   │         ^
 
 error: invalid call of `&`: expected `integer` but found `bool` for argument 2
-   ┌─ tests/checking/typing/binary_bit_and_invalid.move:15:9
+   ┌─ tests/checking/typing/binary_bit_and_invalid.move:15:13
    │
 15 │         1 & false & @0x0 & 0;
-   │         ^^^^^^^^^
+   │             ^^^^^
 
 error: invalid call of `&`: expected `integer` but found `address` for argument 2
-   ┌─ tests/checking/typing/binary_bit_and_invalid.move:15:9
+   ┌─ tests/checking/typing/binary_bit_and_invalid.move:15:21
    │
 15 │         1 & false & @0x0 & 0;
-   │         ^^^^^^^^^^^^^^^^
+   │                     ^^^^
 
 error: invalid call of `&`: expected `integer` but found `()` for argument 1
    ┌─ tests/checking/typing/binary_bit_and_invalid.move:16:9
    │
 16 │         () & ();
-   │         ^^^^^^^
+   │         ^^
 
 error: invalid call of `&`: expected `integer` but found `()` for argument 2
-   ┌─ tests/checking/typing/binary_bit_and_invalid.move:17:9
+   ┌─ tests/checking/typing/binary_bit_and_invalid.move:17:13
    │
 17 │         1 & ();
-   │         ^^^^^^
+   │             ^^
 
 error: invalid call of `&`: expected `integer` but found `(integer, integer)` for argument 1
    ┌─ tests/checking/typing/binary_bit_and_invalid.move:18:9
    │
 18 │         (0, 1) & (0, 1, 2);
-   │         ^^^^^^^^^^^^^^^^^^
+   │         ^^^^^^
 
 error: invalid call of `&`: expected `integer` but found `(integer, integer)` for argument 1
    ┌─ tests/checking/typing/binary_bit_and_invalid.move:19:9
    │
 19 │         (1, 2) & (0, 1);
-   │         ^^^^^^^^^^^^^^^
+   │         ^^^^^^