gen: Add option to replace types via annotations

This is limited to the same namespace, but well, it seems useful enough.

4 files changed, 40 insertions, 4 deletions

diff --git a/src/gen.rs b/src/gen.rs
index a69ee861..e50cddea 100644
--- a/src/gen.rs
+++ b/src/gen.rs
@@ -52,6 +52,10 @@ impl<'r> GenCtx<'r> {
         ret.reverse();
         ret
     }
+
+    fn current_module(&self) -> &Module {
+        self.module_map.get(&self.current_module_id).expect("Module not found!")
+    }
 }
 
 fn first<A, B>((val, _): (A, B)) -> A {
@@ -448,7 +452,9 @@ fn gen_globals(mut ctx: &mut GenCtx,
     let mut defs = vec!();
     gs = remove_redundant_decl(gs);
 
-    for g in gs.into_iter() {
+    for mut g in gs.into_iter() {
+        // XXX unify with anotations both type_blacklisted
+        // and type_opaque (which actually doesn't mean the same).
         if type_blacklisted(ctx, &g) {
             continue;
         }
@@ -462,6 +468,10 @@ fn gen_globals(mut ctx: &mut GenCtx,
             continue;
         }
 
+        if let Some(substituted) = ctx.current_module().translations.get(&g.name()) {
+            g = substituted.clone();
+        }
+
         match g {
             GType(ti) => {
                 let t = ti.borrow().clone();
diff --git a/src/parser.rs b/src/parser.rs
index 538d5d9c..8db8031b 100644
--- a/src/parser.rs
+++ b/src/parser.rs
@@ -467,6 +467,7 @@ fn opaque_ty(ctx: &mut ClangParserCtx, ty: &cx::Type) {
 struct Annotations {
     opaque: bool,
     hide: bool,
+    use_as: Option<String>,
 }
 
 impl Annotations {
@@ -474,6 +475,7 @@ impl Annotations {
         let mut anno = Annotations {
             opaque: false,
             hide: false,
+            use_as: None,
         };
 
         anno.parse(&cursor.comment());
@@ -487,10 +489,10 @@ impl Annotations {
            comment.get_tag_attr_name(0) == "rustbindgen" {
             for i in 0..comment.get_num_tag_attrs() {
                 let name = comment.get_tag_attr_name(i);
-
                 match name.as_str() {
                     "opaque" => self.opaque = true,
                     "hide" => self.hide = true,
+                    "replaces" => self.use_as = Some(comment.get_tag_attr_value(i)),
                     _ => (),
                 }
             }
@@ -860,7 +862,7 @@ fn visit_top(cursor: &Cursor,
         | CXCursor_ClassDecl
         | CXCursor_ClassTemplate => {
             let anno = Annotations::new(cursor);
-            fwd_decl(ctx, cursor, |ctx_| {
+            fwd_decl(ctx, cursor, move |ctx_| {
                 let decl = decl_name(ctx_, cursor);
                 let ci = decl.compinfo();
                 cursor.visit(|c, p| {
@@ -873,7 +875,12 @@ fn visit_top(cursor: &Cursor,
                 if anno.hide {
                     ci.borrow_mut().hide = true;
                 }
-                ctx_.current_module_mut().globals.push(GComp(ci));
+                if let Some(other_type_name) = anno.use_as {
+                    ci.borrow_mut().name = other_type_name.clone();
+                    ctx_.current_module_mut().translations.insert(other_type_name, GComp(ci));
+                } else {
+                    ctx_.current_module_mut().globals.push(GComp(ci));
+                }
             });
             CXChildVisit_Continue
         }
diff --git a/src/types.rs b/src/types.rs
index 792965c2..925efdbf 100644
--- a/src/types.rs
+++ b/src/types.rs
@@ -32,6 +32,9 @@ pub struct Module {
     pub parent_id: Option<ModuleId>,
     // Just for convenience
     pub children_ids: Vec<ModuleId>,
+    /// Types that must be substituted in this module,
+    /// in the form original_name -> substituted_type
+    pub translations: HashMap<String, Global>,
 }
 
 impl Module {
@@ -41,6 +44,7 @@ impl Module {
             globals: vec![],
             parent_id: parent_id,
             children_ids: vec![],
+            translations: HashMap::new(),
         }
     }
 
diff --git a/tests/headers/class_use_as.hpp b/tests/headers/class_use_as.hpp
new file mode 100644
index 00000000..a4e36ded
--- /dev/null
+++ b/tests/headers/class_use_as.hpp
@@ -0,0 +1,15 @@
+
+/**
+ * <div rustbindgen="true" replaces="whatever"></div>
+ */
+struct whatever_replacement {
+    int replacement;
+};
+
+struct whatever {
+    int b;
+};
+
+struct container {
+    whatever c;
+};