Adding support for stringifier functions in Kotlin

core/src/hir/elision.rs

@@ -114,7 +114,6 @@ pub trait LifetimeLowerer {
     /// Lowers a slice of [`ast::Lifetime`]s by calling
     /// [`LifetimeLowerer::lower_lifetime`] repeatedly.
     ///
-
     /// `type_generics` is the full list of generics on the type definition of the type
     /// this lifetimes list is found on (needed for generating anon lifetimes)
     fn lower_lifetimes(
@@ -143,7 +142,6 @@ pub trait LifetimeLowerer {
     ///
     /// `type_generics` is the full list of generics on the type definition of the type
     /// this generics list is found on (needed for generating anon lifetimes)
-
     fn lower_generics(
         &mut self,
         lifetimes: &[ast::Lifetime],

core/src/hir/lifetimes.rs

@@ -48,7 +48,6 @@ impl LifetimeEnv {
 
     /// Get an iterator of all lifetimes that this must live as long as (including itself)
     /// with the first lifetime always being returned first
-
     pub fn all_shorter_lifetimes(
         &self,
         lt: impl Borrow<Lifetime>,

runtime/src/slices.rs

@@ -13,12 +13,12 @@ pub struct DiplomatSlice<'a, T> {
     phantom: PhantomData<&'a [T]>,
 }
 
-impl<'a, T> Clone for DiplomatSlice<'a, T> {
+impl<T> Clone for DiplomatSlice<'_, T> {
     fn clone(&self) -> Self {
         *self
     }
 }
-impl<'a, T> Copy for DiplomatSlice<'a, T> {}
+impl<T> Copy for DiplomatSlice<'_, T> {}
 
 impl<'a, T> From<&'a [T]> for DiplomatSlice<'a, T> {
     fn from(x: &'a [T]) -> Self {
@@ -46,7 +46,7 @@ impl<'a, T> From<DiplomatSlice<'a, T>> for &'a [T] {
     }
 }
 
-impl<'a, T> Deref for DiplomatSlice<'a, T> {
+impl<T> Deref for DiplomatSlice<'_, T> {
     type Target = [T];
     fn deref(&self) -> &[T] {
         (*self).into()
@@ -87,7 +87,7 @@ impl<'a, T> From<DiplomatSliceMut<'a, T>> for &'a mut [T] {
     }
 }
 
-impl<'a, T> Deref for DiplomatSliceMut<'a, T> {
+impl<T> Deref for DiplomatSliceMut<'_, T> {
     type Target = [T];
     fn deref(&self) -> &[T] {
         if self.ptr.is_null() {
@@ -102,7 +102,7 @@ impl<'a, T> Deref for DiplomatSliceMut<'a, T> {
     }
 }
 
-impl<'a, T> DerefMut for DiplomatSliceMut<'a, T> {
+impl<T> DerefMut for DiplomatSliceMut<'_, T> {
     fn deref_mut(&mut self) -> &mut [T] {
         if self.ptr.is_null() {
             debug_assert!(self.len == 0);
@@ -210,7 +210,7 @@ impl<'a> From<DiplomatUtf8StrSlice<'a>> for &'a str {
     }
 }
 
-impl<'a> Deref for DiplomatUtf8StrSlice<'a> {
+impl Deref for DiplomatUtf8StrSlice<'_> {
     type Target = str;
     fn deref(&self) -> &str {
         (*self).into()

tool/src/kotlin/mod.rs

@@ -35,7 +35,7 @@ pub(crate) fn attr_support() -> BackendAttrSupport {
     a.named_constructors = false; // TODO
     a.fallible_constructors = false; // TODO
     a.accessors = false;
-    a.stringifiers = false; // TODO
+    a.stringifiers = true;
     a.comparators = false; // TODO
     a.iterators = true;
     a.iterables = true;
@@ -1188,11 +1188,21 @@ returnVal.option() ?: return null
                     panic!("Can only have one iterable method per opaque struct")
                 }
             }
-            _ => format!(
-                "fun {}({}): {return_ty}",
-                self.formatter.fmt_method_name(method),
-                params
-            ),
+            Some(SpecialMethod::Stringifier) => {
+                if !special_methods.has_stringifier {
+                    special_methods.has_stringifier = true;
+                    "override fun toString(): String".to_string()
+                } else {
+                    panic!("Can only have one stringifier method per opaque struct")
+                }
+            }
+            _ => {
+                format!(
+                    "fun {}({}): {return_ty}",
+                    self.formatter.fmt_method_name(method),
+                    params
+                )
+            }
         };
 
         MethodTpl {
@@ -1901,6 +1911,7 @@ struct SpecialMethods {
     iterator_type: Option<String>,
     indexer_type: Option<IndexerType>,
     iterable_type: Option<String>,
+    has_stringifier: bool,
 }
 
 struct IndexerType {
@@ -1921,6 +1932,7 @@ impl SpecialMethodsImpl {
             iterator_type,
             indexer_type,
             iterable_type,
+            has_stringifier: _,
         }: SpecialMethods,
     ) -> Self {
         let interfaces = iterator_type