Support mapping core::fmt::Debug as a supertrait

diff --git a/c-bindings-gen/src/main.rs b/c-bindings-gen/src/main.rs
index bfadca0ed8dc415be471efa712a620ac21c3fedf..9cd32feb8f7bfe6d1ebeee93e076cfa25c0bf82f 100644 (file)
--- a/c-bindings-gen/src/main.rs
+++ b/c-bindings-gen/src/main.rs
@@ -329,6 +329,13 @@ fn writeln_trait<'a, 'b, W: std::io::Write>(w: &mut W, t: &'a syn::ItemTrait, ty
                                Some(format!("\t/**\n\t * {}\n\t * {}\n\t */\n", hash_docs_a, hash_docs_b))));
                },
                ("Send", _) => {}, ("Sync", _) => {},
+               ("std::fmt::Debug", _)|("core::fmt::Debug", _) => {
+                       let debug_docs = "Return a human-readable \"debug\" string describing this object";
+                       writeln!(w, "\t/// {}", debug_docs).unwrap();
+                       writeln!(w, "\tpub debug_str: extern \"C\" fn (this_arg: *const c_void) -> crate::c_types::Str,").unwrap();
+                       generated_fields.push(("debug_str".to_owned(), None,
+                               Some(format!("\t/**\n\t * {}\n\t */\n", debug_docs))));
+               },
                (s, i) => {
                        // TODO: Both of the below should expose supertrait methods in C++, but doing so is
                        // nontrivial.
@@ -494,6 +501,13 @@ fn writeln_trait<'a, 'b, W: std::io::Write>(w: &mut W, t: &'a syn::ItemTrait, ty
                        writeln!(w, "\t\t{}_clone(self)", trait_name).unwrap();
                        writeln!(w, "\t}}\n}}").unwrap();
                },
+               ("std::fmt::Debug", _)|("core::fmt::Debug", _) => {
+                       writeln!(w, "impl core::fmt::Debug for {} {{", trait_name).unwrap();
+                       writeln!(w, "\tfn fmt(&self, f: &mut core::fmt::Formatter) -> Result<(), core::fmt::Error> {{").unwrap();
+                       writeln!(w, "\t\tf.write_str((self.debug_str)(self.this_arg).into_str())").unwrap();
+                       writeln!(w, "\t}}").unwrap();
+                       writeln!(w, "}}").unwrap();
+               },
                (s, i) => {
                        if let Some(supertrait) = types.crate_types.traits.get(s) {
                                let mut module_iter = s.rsplitn(2, "::");
@@ -827,6 +841,7 @@ fn writeln_impl<W: std::io::Write>(w: &mut W, i: &syn::ItemImpl, types: &mut Typ
                                                        },
                                                        ("Sync", _) => {}, ("Send", _) => {},
                                                        ("std::marker::Sync", _) => {}, ("std::marker::Send", _) => {},
+                                                       ("core::fmt::Debug", _) => {},
                                                        (s, t) => {
                                                                if let Some(supertrait_obj) = types.crate_types.traits.get(s) {
                                                                        writeln!(w, "\t\t{}: crate::{} {{", t, s).unwrap();