Make the order of items coming from implicit template specializations deterministic
Currently we sort items in IR according to
1. Source location, and then
2. `Importer::GetDeclOrder()` <- this one ensures that implicit constructors/destructors come in a certain order
Implicit class template specialization decls and their methods have the same source location, which makes the following code snippet problematic:
```
template <typename T>
struct MyStruct {
void Method(T t);
};
using Alias1 = MyStruct<int>;
using Alias2 = MyStruct<bool>;
```
The generated bindings will contain two structs for the implicit template specializations:
```
pub struct __CcTemplateInst8MyStructIiE {...}
pub struct __CcTemplateInst8MyStructIbE {...}
```
But the order in which they appear is nondeterministic. Same goes for the assertions we generate for these structs, as well as the respective functions in `rs_api_impl.cc`.
This cl addresses the issue by taking into account the mangled name of the class template specialization or function decls when determining the item order.
PiperOrigin-RevId: 456502619
diff --git a/rs_bindings_from_cc/importer.h b/rs_bindings_from_cc/importer.h
index bc495ac..e7556ad 100644
--- a/rs_bindings_from_cc/importer.h
+++ b/rs_bindings_from_cc/importer.h
@@ -22,6 +22,7 @@
#include "rs_bindings_from_cc/importers/typedef_name.h"
#include "rs_bindings_from_cc/ir.h"
#include "clang/AST/Mangle.h"
+#include "clang/AST/RawCommentList.h"
namespace crubit {
@@ -82,6 +83,19 @@
const clang::TypeDecl* decl) const override;
private:
+ class SourceOrderKey;
+ class SourceLocationComparator;
+
+ // Returns a SourceOrderKey for the given `decl` that should be used for
+ // ordering Items.
+ SourceOrderKey GetSourceOrderKey(const clang::Decl* decl) const;
+ // Returns a SourceOrderKey for the given `comment` that should be used for
+ // ordering Items.
+ SourceOrderKey GetSourceOrderKey(const clang::RawComment* comment) const;
+
+ // Returns a name for `decl` that should be used for ordering declarations.
+ std::string GetNameForSourceOrder(const clang::Decl* decl) const;
+
// Returns the item ids of template instantiations that have been triggered
// from the current target. The returned items are in an arbitrary,
// deterministic/reproducible order.
