# HG changeset patch
# User Chris Seaton <chris.seaton@oracle.com>
# Date 1410020353 -3600
# Node ID d51c097cca37898a309bd3814cd634eba6cfef1d
# Parent  0e7894989f37d028de3ad9aa92a9818a0fb2b5c2
Truffle: Add NeverValidAssumption.

diff -r 0e7894989f37 -r d51c097cca37 graal/com.oracle.truffle.api.test/src/com/oracle/truffle/api/test/utilities/NeverValidAssumptionTest.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/graal/com.oracle.truffle.api.test/src/com/oracle/truffle/api/test/utilities/NeverValidAssumptionTest.java	Sat Sep 06 17:19:13 2014 +0100
@@ -0,0 +1,59 @@
+/*
+ * Copyright (c) 2013, 2014, 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.utilities;
+
+import static org.junit.Assert.*;
+
+import org.junit.*;
+
+import com.oracle.truffle.api.nodes.*;
+import com.oracle.truffle.api.utilities.*;
+
+public class NeverValidAssumptionTest {
+
+    @Test
+    public void testCheck() {
+        final NeverValidAssumption assumption = NeverValidAssumption.INSTANCE;
+
+        try {
+            assumption.check();
+            fail();
+        } catch (InvalidAssumptionException e) {
+        } catch (Exception e) {
+            fail();
+        }
+    }
+
+    @Test
+    public void testIsValid() {
+        final NeverValidAssumption assumption = NeverValidAssumption.INSTANCE;
+        assertFalse(assumption.isValid());
+    }
+
+    @Test(expected = UnsupportedOperationException.class)
+    public void testCannotInvalidate() {
+        final NeverValidAssumption assumption = NeverValidAssumption.INSTANCE;
+        assumption.invalidate();
+    }
+
+}
diff -r 0e7894989f37 -r d51c097cca37 graal/com.oracle.truffle.api/src/com/oracle/truffle/api/utilities/NeverValidAssumption.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/graal/com.oracle.truffle.api/src/com/oracle/truffle/api/utilities/NeverValidAssumption.java	Sat Sep 06 17:19:13 2014 +0100
@@ -0,0 +1,61 @@
+/*
+ * Copyright (c) 2013, 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.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * 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.utilities;
+
+import com.oracle.truffle.api.*;
+import com.oracle.truffle.api.nodes.*;
+
+/**
+ * An assumption that is never valid. Used as a placeholder where an assumption is needed that
+ * should be invalid from the start.
+ */
+public final class NeverValidAssumption implements Assumption {
+
+    public static final NeverValidAssumption INSTANCE = new NeverValidAssumption();
+
+    private NeverValidAssumption() {
+    }
+
+    @Override
+    public void check() throws InvalidAssumptionException {
+        throw new InvalidAssumptionException();
+    }
+
+    @Override
+    public void invalidate() {
+        throw new UnsupportedOperationException("Cannot invalidate this assumption - it is never valid");
+    }
+
+    @Override
+    public String getName() {
+        return getClass().getName();
+    }
+
+    @Override
+    public boolean isValid() {
+        return false;
+    }
+
+}