Passing an argument from C++ into JavaScript has 'borrow' semantics rather than ownership semantics. That is, to keep a reference beyond the function call, you must call .clone(). This is necessary to avoid special-casing non-overridden virtual functions. (I don't know if this change will stick. It's possible it will have some problems.)

1 files changed, 47 insertions, 0 deletions

diff --git a/tests/embind/embind.test.js b/tests/embind/embind.test.js
index ae421f27..a6b2e98c 100644
--- a/tests/embind/embind.test.js
+++ b/tests/embind/embind.test.js
@@ -1953,6 +1953,53 @@ module({
             rv.delete();
             cm.flushPendingDeletes();
         });
+
+        test("method arguments with pointer ownership semantics are cleaned up after call", function() {
+            var parent = cm.AbstractClass;
+            var C = parent.extend("C", {
+                abstractMethod: function() {
+                },
+            });
+            var impl = new C;
+            cm.passShared(impl);
+            impl.delete();
+        });
+
+        test("method arguments with pointer ownership semantics can be cloned", function() {
+            var parent = cm.AbstractClass;
+            var owned;
+            var C = parent.extend("C", {
+                abstractMethod: function() {
+                },
+                passShared: function(p) {
+                    owned = p.clone();
+                }
+            });
+            var impl = new C;
+            cm.passShared(impl);
+            impl.delete();
+
+            assert.equal("Derived", owned.getClassName());
+            owned.delete();
+        });
+
+        test("emscripten::val method arguments don't leak", function() {
+            var parent = cm.AbstractClass;
+            var got;
+            var C = parent.extend("C", {
+                abstractMethod: function() {
+                },
+                passVal: function(g) {
+                    got = g;
+                }
+            });
+            var impl = new C;
+            var v = {};
+            cm.passVal(impl, v);
+            impl.delete();
+
+            assert.equal(v, got);
+        });
     });
 
     BaseFixture.extend("registration order", function() {