1 files changed, 154 insertions, 0 deletions
diff --git a/spec/ruby/optional/capi/gc_spec.rb b/spec/ruby/optional/capi/gc_spec.rb
new file mode 100644
index 0000000000..8b70ea4758
--- /dev/null
+++ b/spec/ruby/optional/capi/gc_spec.rb
@@ -0,0 +1,154 @@
+require_relative 'spec_helper'
+
+load_extension("gc")
+
+describe "CApiGCSpecs" do
+  before :each do
+    @f = CApiGCSpecs.new
+  end
+
+  describe "RB_GC_GUARD" do
+    it "forces an object to on stack so it cannot be GC'd early" do
+      @f.RB_GC_GUARD_keep_alive([%w[ab cd ef].join]).should == "abc"
+    end
+
+    it "can be used with any Ruby object" do
+      @f.RB_GC_GUARD(true).should == true
+      @f.RB_GC_GUARD(42).should == 42
+      @f.RB_GC_GUARD(self).should == self
+    end
+
+    it "tolerates being passed invalid pointers" do
+      (0...256).each do |address|
+        @f.RB_GC_GUARD_raw(address).should == nil
+      end
+    end
+  end
+
+  describe "rb_gc_register_address" do
+    it "correctly gets the value from a registered address" do
+      @f.registered_tagged_address.should == 10
+      @f.registered_tagged_address.should.equal?(@f.registered_tagged_address)
+      @f.registered_reference_address.should == "Globally registered data"
+      @f.registered_reference_address.should.equal?(@f.registered_reference_address)
+    end
+
+    it "keeps the value alive even if the value is assigned after rb_gc_register_address() is called" do
+      GC.start
+      @f.registered_before_rb_gc_register_address.should == "registered before rb_gc_register_address()"
+    end
+
+    it "can be called outside Init_" do
+      @f.rb_gc_register_address.should == "rb_gc_register_address() outside Init_"
+      @f.rb_gc_unregister_address
+    end
+  end
+
+  describe "rb_global_variable" do
+    before :all do
+      GC.start
+    end
+
+    describe "keeps the value alive even if the value is assigned after rb_global_variable() is called" do
+      it "for a string" do
+        @f.registered_before_rb_global_variable_string.should == "registered before rb_global_variable()"
+      end
+
+      it "for a bignum" do
+        @f.registered_before_rb_global_variable_bignum.should == 2**63 - 1
+      end
+
+      it "for a Float" do
+        @f.registered_before_rb_global_variable_float.should == 3.14
+      end
+    end
+
+    describe "keeps the value alive when the value is assigned before rb_global_variable() is called" do
+      it "for a string" do
+        @f.registered_after_rb_global_variable_string.should == "registered after rb_global_variable()"
+      end
+
+      it "for a bignum" do
+        @f.registered_after_rb_global_variable_bignum.should == 2**63 - 1
+      end
+
+      it "for a Float" do
+        @f.registered_after_rb_global_variable_float.should == 6.28
+      end
+    end
+  end
+
+  describe "rb_gc_enable" do
+    after do
+      GC.enable
+    end
+
+    it "enables GC when disabled" do
+      GC.disable
+      @f.rb_gc_enable.should == true
+    end
+
+    it "GC stays enabled when enabled" do
+      GC.enable
+      @f.rb_gc_enable.should == false
+    end
+
+    it "disables GC when enabled" do
+      GC.enable
+      @f.rb_gc_disable.should == false
+    end
+
+    it "GC stays disabled when disabled" do
+      GC.disable
+      @f.rb_gc_disable.should == true
+    end
+  end
+
+  describe "rb_gc" do
+    it "increases gc count" do
+      gc_count = GC.count
+      @f.rb_gc
+      GC.count.should > gc_count
+    end
+  end
+
+  describe "rb_gc_adjust_memory_usage" do
+    # Just check that it does not throw, as it seems hard to observe any effect
+    it "adjusts the amount of registered external memory" do
+      -> {
+        @f.rb_gc_adjust_memory_usage(8)
+        @f.rb_gc_adjust_memory_usage(-8)
+      }.should_not.raise
+    end
+  end
+
+  describe "rb_gc_register_mark_object" do
+    it "can be called with an object" do
+      @f.rb_gc_register_mark_object(Object.new).should == nil
+    end
+
+    it "keeps the value alive even if the value is not referenced by any Ruby object" do
+      @f.rb_gc_register_mark_object_not_referenced_float.should == 1.61
+    end
+  end
+
+  describe "rb_gc_latest_gc_info" do
+    it "raises a TypeError when hash or symbol not given" do
+      -> { @f.rb_gc_latest_gc_info("foo") }.should.raise(TypeError)
+    end
+
+    it "raises an ArgumentError when unknown symbol given" do
+      -> { @f.rb_gc_latest_gc_info(:unknown) }.should.raise(ArgumentError)
+    end
+
+    it "returns the populated hash when a hash is given" do
+      h = {}
+      @f.rb_gc_latest_gc_info(h).should == h
+      h.size.should_not == 0
+    end
+
+    it "returns a value when symbol is given" do
+      @f.rb_gc_latest_gc_info(:state).should.is_a?(Symbol)
+    end
+  end
+end