--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/graal/com.oracle.truffle.api.test/src/com/oracle/truffle/api/test/tools/CoverageTrackerTest.java	Tue Jan 27 20:27:25 2015 -0800
@@ -0,0 +1,114 @@
+/*
+ * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+package com.oracle.truffle.api.test.tools;
+
+import static com.oracle.truffle.api.test.tools.TestNodes.*;
+import static org.junit.Assert.*;
+
+import org.junit.*;
+
+import com.oracle.truffle.api.instrument.*;
+import com.oracle.truffle.api.nodes.*;
+import com.oracle.truffle.api.tools.*;
+
+public class CoverageTrackerTest {
+
+    @Test
+    public void testNoExecution() {
+        final CoverageTracker tool = new CoverageTracker();
+        assertEquals(tool.getCounts().entrySet().size(), 0);
+        tool.install();
+        assertEquals(tool.getCounts().entrySet().size(), 0);
+        tool.setEnabled(false);
+        assertEquals(tool.getCounts().entrySet().size(), 0);
+        tool.setEnabled(true);
+        assertEquals(tool.getCounts().entrySet().size(), 0);
+        tool.reset();
+        assertEquals(tool.getCounts().entrySet().size(), 0);
+        tool.dispose();
+        assertEquals(tool.getCounts().entrySet().size(), 0);
+    }
+
+    @Test
+    public void testToolCreatedTooLate() {
+        final RootNode expr13rootNode = createExpr13TestRootNode();
+        final CoverageTracker tool = new CoverageTracker();
+        tool.install();
+        assertEquals(13, expr13rootNode.execute(null));
+        assertTrue(tool.getCounts().isEmpty());
+        tool.dispose();
+    }
+
+    @Test
+    public void testToolInstalledcTooLate() {
+        final CoverageTracker tool = new CoverageTracker();
+        final RootNode expr13rootNode = createExpr13TestRootNode();
+        tool.install();
+        assertEquals(13, expr13rootNode.execute(null));
+        assertTrue(tool.getCounts().isEmpty());
+        tool.dispose();
+    }
+
+    @Test
+    public void testCountingCoverage() {
+        final CoverageTracker tool = new CoverageTracker();
+        tool.install();
+        final RootNode expr13rootNode = createExpr13TestRootNode();
+
+        // Not probed yet.
+        assertEquals(13, expr13rootNode.execute(null));
+        assertTrue(tool.getCounts().isEmpty());
+
+        final Node addNode = expr13rootNode.getChildren().iterator().next();
+        final Probe probe = addNode.probe();
+
+        // Probed but not tagged yet.
+        assertEquals(13, expr13rootNode.execute(null));
+        assertTrue(tool.getCounts().isEmpty());
+
+        probe.tagAs(StandardSyntaxTag.STATEMENT, "fake statement for testing");
+
+        // Counting now; execute once
+        assertEquals(13, expr13rootNode.execute(null));
+
+        final Long[] longs1 = tool.getCounts().get(addNode.getSourceSection().getSource());
+        assertNotNull(longs1);
+        assertEquals(longs1.length, 2);
+        assertNull(longs1[0]);  // Line 1 is empty (text lines are 1-based)
+        assertEquals(1L, longs1[1].longValue());  // Expression is on line 2
+
+        // Execute 99 more times
+        for (int i = 0; i < 99; i++) {
+            assertEquals(13, expr13rootNode.execute(null));
+        }
+
+        final Long[] longs100 = tool.getCounts().get(addNode.getSourceSection().getSource());
+        assertNotNull(longs100);
+        assertEquals(longs100.length, 2);
+        assertNull(longs100[0]);
+        assertEquals(100L, longs100[1].longValue());
+
+        tool.dispose();
+    }
+
+}