adjust spans & tweak errors for maximum UX

Signed-off-by: KtorZ <matthias.benkort@gmail.com>

crates/aiken-lang/src/tipo/environment.rs

@@ -505,8 +505,10 @@ impl<'a> Environment<'a> {
                 }),
 
             Some(Namespace::Type(t)) => {
+                let type_location = location.map(|start, _| (start, start + t.len()));
+
                 let parent_type = self.module_types.get(t).ok_or_else(|| Error::UnknownType {
-                    location,
+                    location: type_location,
                     name: t.to_string(),
                     types: self.known_type_names(),
                 })?;
@@ -514,8 +516,8 @@ impl<'a> Environment<'a> {
                 self.unused_modules.remove(&parent_type.module);
 
                 self.get_fully_qualified_value_constructor(
-                    (parent_type.module.as_str(), location),
-                    (t, location),
+                    (parent_type.module.as_str(), type_location),
+                    (t, type_location),
                     (name, location.map(|start, end| (start + t.len() + 1, end))),
                 )
             }

crates/aiken-lang/src/tipo/error.rs

@@ -808,7 +808,7 @@ Perhaps, try the following:
     },
 
     #[error(
-        "I looked for '{}' in '{}' but couldn't find it.\n",
+        "I looked for '{}' in module '{}' but couldn't find it.\n",
         name.if_supports_color(Stdout, |s| s.purple()),
         module_name.if_supports_color(Stdout, |s| s.purple())
     )]
@@ -822,7 +822,7 @@ Perhaps, try the following:
         )
     ))]
     UnknownModuleType {
-        #[label("unknown import")]
+        #[label("not exported?")]
         location: Span,
         name: String,
         module_name: String,
@@ -1530,13 +1530,14 @@ fn suggest_import_constructor() -> String {
              │ {keyword_pub} {keyword_type} {type_Pet} {{           │ {keyword_use} aiken/pet.{{{type_Pet}, {variant_Dog}}}
              │   {variant_Cat}                    │
              │   {variant_Dog}                    │ {keyword_fn} foo(pet: {type_Pet}) {{
-             │ }}                        │   {keyword_when} pet {keyword_is} {{
-                                        │     pet.{variant_Cat} -> // ...
+             │   {variant_Fox}                    │   {keyword_when} pet {keyword_is} {{
+             │ }}                        │     pet.{variant_Cat} -> // ...
                                         │     {variant_Dog} -> // ...
+                                        │     {type_Pet}.{variant_Fox} -> // ...
                                         │   }}
                                         │ }}
 
-           You must import its constructors explicitly to use them, or prefix them with the module's name.
+           You must import its constructors explicitly to use them, or prefix them with the module or type's name.
         "#
         , keyword_fn =  "fn".if_supports_color(Stdout, |s| s.yellow())
         , keyword_is = "is".if_supports_color(Stdout, |s| s.yellow())
@@ -1553,6 +1554,9 @@ fn suggest_import_constructor() -> String {
         , variant_Dog = "Dog"
             .if_supports_color(Stdout, |s| s.bright_blue())
             .if_supports_color(Stdout, |s| s.bold())
+        , variant_Fox = "Fox"
+            .if_supports_color(Stdout, |s| s.bright_blue())
+            .if_supports_color(Stdout, |s| s.bold())
     }
 }
 

crates/aiken-lang/src/tipo/expr.rs

@@ -1078,7 +1078,10 @@ impl<'a, 'b> ExprTyper<'a, 'b> {
             } if TypeConstructor::might_be(type_name) => {
                 return self.infer_type_constructor_access(
                     (type_name, type_location),
-                    (&label, access_location),
+                    (
+                        &label,
+                        access_location.map(|start, end| (start + type_name.len() + 1, end)),
+                    ),
                 );
             }
 
@@ -1094,8 +1097,16 @@ impl<'a, 'b> ExprTyper<'a, 'b> {
                 {
                     return self.infer_inner_type_constructor_access(
                         (module_name, *module_location),
-                        (type_name, type_location),
-                        (&label, access_location),
+                        (
+                            type_name,
+                            type_location.map(|start, end| (start + module_name.len() + 1, end)),
+                        ),
+                        (
+                            &label,
+                            access_location.map(|start, end| {
+                                (start + module_name.len() + type_name.len() + 2, end)
+                            }),
+                        ),
                     );
                 }
             }
@@ -1203,6 +1214,8 @@ impl<'a, 'b> ExprTyper<'a, 'b> {
         (type_name, type_location): (&str, Span),
         (label, label_location): (&str, Span),
     ) -> Result<TypedExpr, Error> {
+        self.environment.increment_usage(type_name);
+
         let parent_type = self
             .environment
             .module_types
@@ -1234,6 +1247,9 @@ impl<'a, 'b> ExprTyper<'a, 'b> {
             (type_name, type_location),
             (label, label_location),
         )?;
+
+        self.environment.unused_modules.remove(module_name);
+
         self.infer_module_access(
             module_name,
             label.to_string(),

crates/aiken-project/src/error.rs

@@ -731,7 +731,7 @@ impl Warning {
 
 impl Debug for Warning {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        default_miette_handler(0)
+        default_miette_handler(1)
             .debug(
                 &DisplayWarning {
                     title: &self.to_string(),