Fix deleted destructors.

Fixes #829.

Author: adetaylor

Cargo.toml

@@ -37,5 +37,5 @@ exclude = ["examples/s2", "examples/steam-mini", "examples/subclass", "examples/
 #[patch.crates-io]
 #cxx = { path="../cxx" }
 #cxx-gen = { path="../cxx/gen/lib" }
-#autocxx-bindgen = { path="../bindgen" }
+#autocxx-bindgen = { path="../bindgen/bindgen" }
 #moveit = { path="../moveit" }

engine/src/conversion/analysis/abstract_types.rs

@@ -18,7 +18,7 @@ use super::{
 };
 use crate::conversion::{
     analysis::{depth_first::fields_and_bases_first, fun::ReceiverMutability},
-    api::{ApiName, TypeKind},
+    api::{ApiName, CppVisibility, DeletedOrDefaulted, FuncToConvert, TypeKind},
     error_reporter::{convert_apis, convert_item_apis},
     ConvertErrorFromCpp,
 };
@@ -147,13 +147,49 @@ pub(crate) fn mark_types_abstract(apis: ApiVec<FnPrePhase2>) -> ApiVec<FnPrePhas
         }
     }
 
+    // While we're here, we'll look for types which are non-destructible.
+    let non_destructible_types: HashSet<QualifiedName> = apis
+        .iter()
+        .filter_map(|api| match api {
+            Api::Function {
+                fun,
+                analysis:
+                    FnAnalysis {
+                        kind:
+                            FnKind::TraitMethod {
+                                kind: TraitMethodKind::Destructor,
+                                impl_for,
+                                ..
+                            },
+                        ..
+                    },
+                ..
+            } if matches!(
+                fun.as_ref(),
+                FuncToConvert {
+                    cpp_vis: CppVisibility::Private,
+                    ..
+                } | FuncToConvert {
+                    is_deleted: DeletedOrDefaulted::Deleted,
+                    ..
+                }
+            ) =>
+            {
+                Some(impl_for.clone())
+            }
+            _ => None,
+        })
+        .collect();
+
     // mark abstract types as abstract
     let mut apis: ApiVec<_> = apis
         .into_iter()
         .map(|mut api| {
             if let Api::Struct { name, analysis, .. } = &mut api {
                 if abstract_classes.contains(&name.name) {
                     analysis.pod.kind = TypeKind::Abstract;
+                } else if non_destructible_types.contains(&name.name) {
+                    analysis.pod.kind = TypeKind::NotDestructible;
                 }
             }
             api
@@ -172,7 +208,7 @@ pub(crate) fn mark_types_abstract(apis: ApiVec<FnPrePhase2>) -> ApiVec<FnPrePhas
                         ..
                     },
                     ..
-            } if abstract_classes.contains(self_ty)
+            } if abstract_classes.contains(self_ty) || non_destructible_types.contains(self_ty)
         )
     });
 
@@ -206,6 +242,25 @@ pub(crate) fn mark_types_abstract(apis: ApiVec<FnPrePhase2>) -> ApiVec<FnPrePhas
         {
             Err(ConvertErrorFromCpp::AbstractNestedType)
         }
+        Api::Struct {
+            analysis:
+                PodAndConstructorAnalysis {
+                    pod:
+                        PodAnalysis {
+                            kind: TypeKind::NotDestructible,
+                            ..
+                        },
+                    ..
+                },
+            ..
+        } if api
+            .cpp_name()
+            .as_ref()
+            .map(|n| n.contains("::"))
+            .unwrap_or_default() =>
+        {
+            Err(ConvertErrorFromCpp::NonDestructibleNestedType)
+        }
         _ => Ok(Box::new(std::iter::once(api))),
     });
 

engine/src/conversion/analysis/constructor_deps.rs

@@ -10,7 +10,7 @@ use indexmap::map::IndexMap as HashMap;
 
 use crate::{
     conversion::{
-        api::{Api, ApiName, StructDetails, TypeKind},
+        api::{Api, ApiName, StructDetails},
         apivec::ApiVec,
         convert_error::ConvertErrorWithContext,
         error_reporter::convert_apis,
@@ -51,8 +51,7 @@ fn decorate_struct(
     constructors_and_allocators_by_type: &mut HashMap<QualifiedName, Vec<QualifiedName>>,
 ) -> Result<Box<dyn Iterator<Item = Api<FnPhase>>>, ConvertErrorWithContext> {
     let pod = fn_struct.pod;
-    let is_abstract = matches!(pod.kind, TypeKind::Abstract);
-    let constructor_and_allocator_deps = if is_abstract || pod.is_generic {
+    let constructor_and_allocator_deps = if !pod.kind.is_instantiable() || pod.is_generic {
         Vec::new()
     } else {
         constructors_and_allocators_by_type

engine/src/conversion/api.rs

@@ -38,13 +38,21 @@ use super::{
 
 #[derive(Copy, Clone, Eq, PartialEq, Debug)]
 pub(crate) enum TypeKind {
-    Pod,    // trivial. Can be moved and copied in Rust.
-    NonPod, // has destructor or non-trivial move constructors. Can only hold by UniquePtr
+    Pod,      // trivial. Can be moved and copied in Rust.
+    NonPod,   // has destructor or non-trivial move constructors. Can only hold by UniquePtr
     Abstract, // has pure virtual members - can't even generate UniquePtr.
-            // It's possible that the type itself isn't pure virtual, but it inherits from
-            // some other type which is pure virtual. Alternatively, maybe we just don't
-            // know if the base class is pure virtual because it wasn't on the allowlist,
-            // in which case we'll err on the side of caution.
+    // It's possible that the type itself isn't pure virtual, but it inherits from
+    // some other type which is pure virtual. Alternatively, maybe we just don't
+    // know if the base class is pure virtual because it wasn't on the allowlist,
+    // in which case we'll err on the side of caution.
+    NotDestructible, // private or deleted destructor. We treat it the same as Abstract.
+}
+
+impl TypeKind {
+    /// Whether this TypeKind can be instantiated.
+    pub(crate) fn is_instantiable(&self) -> bool {
+        !matches!(self, Self::Abstract | Self::NotDestructible)
+    }
 }
 
 /// C++ visibility.

engine/src/conversion/codegen_rs/mod.rs

@@ -946,7 +946,7 @@ impl<'a> RsCodeGenerator<'a> {
                     }
                 }
             }
-            TypeKind::Abstract => {
+            TypeKind::Abstract | TypeKind::NotDestructible => {
                 if is_generic {
                     RsCodegenResult::default()
                 } else {

engine/src/conversion/convert_error.rs

@@ -105,6 +105,8 @@ pub enum ConvertErrorFromCpp {
     RustTypeWithAPath(QualifiedName),
     #[error("This type is nested within another struct/class, yet is abstract (or is not on the allowlist so we can't be sure). This is not yet supported by autocxx. If you don't believe this type is abstract, add it to the allowlist.")]
     AbstractNestedType,
+    #[error("This type is nested within another struct/class, yet is not destructible (private or deleted destructor). This is not yet supported by autocxx.")]
+    NonDestructibleNestedType,
     #[error("This typedef was nested within another struct/class. autocxx is unable to represent inner types if they might be abstract. Unfortunately, autocxx couldn't prove that this type isn't abstract, so it can't represent it.")]
     NestedOpaqueTypedef,
     #[error(

integration-tests/tests/integration_test.rs

@@ -12293,6 +12293,59 @@ fn test_cpp_union_pod() {
     run_test_expect_fail("", hdr, quote! {}, &[], &["CorrelationId_t_"]);
 }
 
+#[test]
+fn test_deleted_destructor() {
+    let hdr = indoc! {"
+        #include <stdarg.h>
+        class A {
+        public:
+            void foo();
+            ~A() = delete;
+        };
+        inline A* get_a() {
+            static A* a = new A();
+            return a;
+        }
+    "};
+    run_test("", hdr, quote! {}, &["A", "get_a"], &[]);
+    run_test_expect_fail(
+        "",
+        hdr,
+        quote! {
+            let _ = ffi::A::within_unique_ptr();
+        },
+        &["A", "get_a"],
+        &[],
+    );
+}
+
+#[test]
+fn test_private_destructor() {
+    let hdr = indoc! {"
+        #include <stdarg.h>
+        class A {
+        public:
+            void foo();
+        private:
+            ~A() {};
+        };
+        inline A* get_a() {
+            static A* a = new A();
+            return a;
+        }
+    "};
+    run_test("", hdr, quote! {}, &["A", "get_a"], &[]);
+    run_test_expect_fail(
+        "",
+        hdr,
+        quote! {
+            let _ = ffi::A::within_unique_ptr();
+        },
+        &["A", "get_a"],
+        &[],
+    );
+}
+
 // Yet to test:
 // - Ifdef
 // - Out param pointers