[vala/staging] tests: Add "missing class prerequisite for interface" test to increase coverage

[Rico Tzschichholz <ricotz src gnome org>]

commit 458d5f501aa462f74412322ff8e6997fd674fcfe
Author: Rico Tzschichholz <ricotz ubuntu com>
Date:   Fri Sep 21 15:59:56 2018 +0200

    tests: Add "missing class prerequisite for interface" test to increase coverage

 tests/Makefile.am            |  1 +
 tests/objects/bug554329.test | 16 ++++++++++++++++
 2 files changed, 17 insertions(+)
---
diff --git a/tests/Makefile.am b/tests/Makefile.am
index f4c0372e0..d71fb4650 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -259,6 +259,7 @@ TESTS = \
        objects/test-029.vala \
        objects/test-034.vala \
        objects/bug541728.test \
+       objects/bug554329.test \
        objects/bug564011.test \
        objects/bug564090.test \
        objects/bug566909.vala \
diff --git a/tests/objects/bug554329.test b/tests/objects/bug554329.test
new file mode 100644
index 000000000..50442041b
--- /dev/null
+++ b/tests/objects/bug554329.test
@@ -0,0 +1,16 @@
+Invalid Code
+
+interface IFoo {
+    public abstract void bar ();
+}
+
+class Foo : IFoo {
+    public void bar () {
+    }
+}
+
+void main () {
+       Foo foo = new Foo ();
+       IFoo ifoo = foo;
+       ifoo.bar ();
+}