Fix array initializer analysis (#2925)

* Fix array initializer analysis: improved semantic checking for arrays with inferred or fixed length,
* Update phrasing

---------

Co-authored-by: Christoffer Lerno <christoffer@aegik.com>

releasenotes.md

@@ -14,6 +14,7 @@
 - Individual warning settings added.
 - Change typedef and const enums to not convert from literals by default.
 - Add `@constinit` to allow old typedef behaviour.
+- Include actual element count in the error message when the array initializer size does not match the expected size.
 
 ### Stdlib changes
 - Summarize sort macros as generic function wrappers to reduce the amount of generated code. #2831

src/compiler/sema_initializers.c

@@ -350,7 +350,7 @@ static inline bool sema_expr_analyse_array_plain_initializer(SemaContext *contex
 	}
 	if (expected_members > 0 && count > 0 && count != expected_members)
 	{
-		RETURN_SEMA_ERROR(elements[0], "Too %s elements in initializer, expected %u.", count > expected_members ? "many" : "few", expected_members);
+		RETURN_SEMA_ERROR(elements[0], "Too %s (%u) elements in initializer, expected %u.", count > expected_members ? "many" : "few", count, expected_members);
 	}
 
 	bool optional = false;
@@ -451,7 +451,7 @@ static inline bool sema_expr_analyse_array_plain_initializer(SemaContext *contex
 	if (!inferred_len && expected_members > count)
 	{
 		if (no_match_ref) goto NO_MATCH;
-		RETURN_SEMA_ERROR(elements[count - 1], "Too few elements in initializer, %d elements are needed.", expected_members);
+		RETURN_SEMA_ERROR(elements[count - 1], "Too few elements in initializer, %d elements are needed. Current count: %d.", expected_members, count);
 	}
 
 	initializer->resolve_status = RESOLVE_DONE;

test/test_suite/arrays/array_initializer_size_err.c3

@@ -0,0 +1,4 @@
+fn void main()
+{
+    const int[3] ARR = {1, 2}; // #error: Too few (2) elements in initializer, expected 3
+}

test/test_suite/arrays/array_initializer_size_err2.c3

@@ -0,0 +1,4 @@
+fn void main()
+{
+    const int[3] ARR = {1, 2, 3, 4}; // #error:  Too many (4) elements in initializer, expected 3
+}

test/test_suite/arrays/array_of_inferred_array.c3

@@ -4,5 +4,5 @@ macro void test(int[2][6] a)
 }
 fn void main()
 {
-	test({ { 1, 2 } }); // #error: Too few elements in initializer
+	test({ { 1, 2 } }); // #error:  Too few (1) elements in initializer, expected 6
 }