Merge pull request #2952 from rtfeldman/ability-unused-method-reporting

Ability unused method reporting

compiler/can/src/def.rs

@@ -203,7 +203,7 @@ pub(crate) fn canonicalize_defs<'a>(
     env: &mut Env<'a>,
     mut output: Output,
     var_store: &mut VarStore,
-    original_scope: &Scope,
+    mut scope: Scope,
     loc_defs: &'a [&'a Loc<ast::Def<'a>>],
     pattern_type: PatternType,
 ) -> (CanDefs, Scope, Output, MutMap<Symbol, Region>) {
@@ -224,30 +224,19 @@ pub(crate) fn canonicalize_defs<'a>(
     // This naturally handles recursion too, because a given expr which refers
     // to itself won't be processed until after its def has been added to scope.
 
-    // Record both the original and final idents from the scope,
-    // so we can diff them while detecting unused defs.
-    let mut scope = original_scope.clone();
     let num_defs = loc_defs.len();
-
+    let mut pending_type_defs = Vec::with_capacity(num_defs);
-    let mut type_defs = Vec::with_capacity(num_defs);
     let mut value_defs = Vec::with_capacity(num_defs);
 
     for loc_def in loc_defs {
         match loc_def.value.unroll_def() {
-            Ok(type_def) => type_defs.push(Loc::at(loc_def.region, type_def)),
+            Ok(type_def) => {
+                pending_type_defs.push(to_pending_type_def(env, type_def, &mut scope, pattern_type))
+            }
             Err(value_def) => value_defs.push(Loc::at(loc_def.region, value_def)),
         }
     }
 
-    // We need to canonicalize all the type defs first.
-    // Clippy is wrong - we do need the collect, otherwise "env" and "scope" are captured for
-    // longer than we'd like.
-    #[allow(clippy::needless_collect)]
-    let pending_type_defs = type_defs
-        .into_iter()
-        .map(|loc_def| to_pending_type_def(env, loc_def.value, &mut scope, pattern_type))
-        .collect::<Vec<_>>();
-
     if cfg!(debug_assertions) {
         env.home.register_debug_idents(&env.ident_ids);
     }
@@ -452,7 +441,6 @@ pub(crate) fn canonicalize_defs<'a>(
         &mut output,
         var_store,
         &mut scope,
-        &mut symbols_introduced,
         abilities,
         &abilities_in_scope,
         pattern_type,
@@ -554,7 +542,6 @@ fn resolve_abilities<'a>(
     output: &mut Output,
     var_store: &mut VarStore,
     scope: &mut Scope,
-    symbols_introduced: &mut MutMap<Symbol, Region>,
     abilities: MutMap<Symbol, (Loc<Symbol>, &[AbilityMember])>,
     abilities_in_scope: &[Symbol],
     pattern_type: PatternType,
@@ -598,8 +585,6 @@ fn resolve_abilities<'a>(
                 }
             };
 
-            symbols_introduced.insert(member_sym, name_region);
-
             if pattern_type == PatternType::TopLevelDef {
                 env.top_level_symbols.insert(member_sym);
             }
@@ -1402,7 +1387,7 @@ pub fn can_defs_with_return<'a>(
         env,
         Output::default(),
         var_store,
-        &scope,
+        scope,
         loc_defs,
         PatternType::DefExpr,
     );

compiler/can/src/module.rs

@@ -289,7 +289,7 @@ pub fn canonicalize_module_defs<'a>(
         &mut env,
         Output::default(),
         var_store,
-        &scope,
+        scope,
         &desugared,
         PatternType::TopLevelDef,
     );

reporting/tests/test_reporting.rs

@@ -9203,16 +9203,6 @@ I need all branches in an `if` to have the same type!
                     | a has Ability
 
                  at the end of the type.
-
-                ── UNUSED DEFINITION ───────────────────────────────────── /code/proj/Main.roc ─
-
-                `ab` is not used anywhere in your code.
-
-                3│  Ability has ab : a -> {} | a has Ability
-                                ^^
-
-                If you didn't intend on using `ab` then remove it so future readers of
-                your code don't wonder why it is there.
                 "#
             ),
         )
@@ -9289,16 +9279,6 @@ I need all branches in an `if` to have the same type!
 
                 If you didn't intend on using `Ability` then remove it so future readers
                 of your code don't wonder why it is there.
-
-                ── UNUSED DEFINITION ───────────────────────────────────── /code/proj/Main.roc ─
-
-                `ab` is not used anywhere in your code.
-
-                3│  Ability has ab : {} -> {}
-                                ^^
-
-                If you didn't intend on using `ab` then remove it so future readers of
-                your code don't wonder why it is there.
                 "#
             ),
         )
@@ -9330,16 +9310,6 @@ I need all branches in an `if` to have the same type!
                 are a part of.
 
                 Hint: Did you mean to bind the `Hash` ability instead?
-
-                ── UNUSED DEFINITION ───────────────────────────────────── /code/proj/Main.roc ─
-
-                `hash` is not used anywhere in your code.
-
-                4│  Hash has hash : a, b -> Num.U64 | a has Eq, b has Hash
-                             ^^^^
-
-                If you didn't intend on using `hash` then remove it so future readers of
-                your code don't wonder why it is there.
                 "#
             ),
         )
@@ -9371,16 +9341,6 @@ I need all branches in an `if` to have the same type!
                 looking at specializations!
 
                 Hint: Did you mean to only bind `a` to `Eq`?
-
-                ── UNUSED DEFINITION ───────────────────────────────────── /code/proj/Main.roc ─
-
-                `eq` is not used anywhere in your code.
-
-                3│  Eq has eq : a, b -> Bool.Bool | a has Eq, b has Eq
-                           ^^
-
-                If you didn't intend on using `eq` then remove it so future readers of
-                your code don't wonder why it is there.
                 "#
             ),
         )
@@ -9424,16 +9384,6 @@ I need all branches in an `if` to have the same type!
                     a has Hash
 
                 Otherwise, the function does not need to be part of the ability!
-
-                ── UNUSED DEFINITION ───────────────────────────────────── /code/proj/Main.roc ─
-
-                `hash` is not used anywhere in your code.
-
-                3│  Hash has hash : (a | a has Hash) -> Num.U64
-                             ^^^^
-
-                If you didn't intend on using `hash` then remove it so future readers of
-                your code don't wonder why it is there.
                 "#
             ),
         )