Constant evaluation support

editor/tools/plugins/com.google.dart.engine/src/com/google/dart/engine/internal/object/NumState.java

Index: editor/tools/plugins/com.google.dart.engine/src/com/google/dart/engine/internal/object/NumState.java
diff --git a/editor/tools/plugins/com.google.dart.engine/src/com/google/dart/engine/internal/object/NumState.java b/editor/tools/plugins/com.google.dart.engine/src/com/google/dart/engine/internal/object/NumState.java
new file mode 100644
index 0000000000000000000000000000000000000000..fae41c21c2b43d7b63fa5bb883e3fab97db24c3b
--- /dev/null
+++ b/editor/tools/plugins/com.google.dart.engine/src/com/google/dart/engine/internal/object/NumState.java
@@ -0,0 +1,148 @@
+/*
+ * Copyright (c) 2013, the Dart project authors.
+ * 
+ * Licensed under the Eclipse Public License v1.0 (the "License"); you may not use this file except
+ * in compliance with the License. You may obtain a copy of the License at
+ * 
+ * http://www.eclipse.org/legal/epl-v10.html
+ * 
+ * Unless required by applicable law or agreed to in writing, software distributed under the License
+ * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
+ * or implied. See the License for the specific language governing permissions and limitations under
+ * the License.
+ */
+package com.google.dart.engine.internal.object;
+
+import com.google.dart.engine.error.CompileTimeErrorCode;
+
+import java.math.BigInteger;
+
+/**
+ * Instances of the class {@code NumState} represent the state of an object representing a number of
+ * an unknown type (a 'num').
+ */
+public class NumState extends InstanceState {
+  /**
+   * A state that can be used to represent a number whose value is not known.
+   */
+  public static final NumState UNKNOWN_VALUE = new NumState();
+
+  /**
+   * Initialize a newly created state to represent a number. Clients should use the value of the
+   * static constant {@link #UNKNOWN_VALUE} rather than creating new instances of this class.
+   */
+  public NumState() {
+    super();
+  }
+
+  @Override
+  public NumState add(InstanceState rightOperand) throws EvaluationException {
+    assertNumOrNull(rightOperand);
+    return UNKNOWN_VALUE;
+  }
+
+  @Override
+  public StringState convertToString() {
+    return StringState.UNKNOWN_VALUE;
+  }
+
+  @Override
+  public NumState divide(InstanceState rightOperand) throws EvaluationException {
+    assertNumOrNull(rightOperand);
+    return UNKNOWN_VALUE;
+  }
+
+  @Override
+  public boolean equals(Object object) {
+    return object instanceof NumState;
+  }
+
+  @Override
+  public BoolState equalEqual(InstanceState rightOperand) throws EvaluationException {
+    assertBoolNumStringOrNull(rightOperand);
+    return BoolState.UNKNOWN_VALUE;
+  }
+
+  @Override
+  public String getTypeName() {
+    return "num"; //$NON-NLS-0$
+  }
+
+  @Override
+  public BoolState greaterThan(InstanceState rightOperand) throws EvaluationException {
+    assertNumOrNull(rightOperand);
+    return BoolState.UNKNOWN_VALUE;
+  }
+
+  @Override
+  public BoolState greaterThanOrEqual(InstanceState rightOperand) throws EvaluationException {
+    assertNumOrNull(rightOperand);
+    return BoolState.UNKNOWN_VALUE;
+  }
+
+  @Override
+  public int hashCode() {
+    return 7;
+  }
+
+  @Override
+  public IntState integerDivide(InstanceState rightOperand) throws EvaluationException {
+    assertNumOrNull(rightOperand);
+    if (rightOperand instanceof IntState) {
+      BigInteger rightValue = ((IntState) rightOperand).getValue();
+      if (rightValue == null) {
+        return IntState.UNKNOWN_VALUE;
+      } else if (rightValue.equals(BigInteger.ZERO)) {
+        throw new EvaluationException(CompileTimeErrorCode.CONST_EVAL_THROWS_IDBZE);
+      }
+    } else if (rightOperand instanceof DynamicState) {
+      return IntState.UNKNOWN_VALUE;
+    }
+    return IntState.UNKNOWN_VALUE;
+  }
+
+  @Override
+  public boolean isBoolNumStringOrNull() {
+    return true;
+  }
+
+  @Override
+  public BoolState lessThan(InstanceState rightOperand) throws EvaluationException {
+    assertNumOrNull(rightOperand);
+    return BoolState.UNKNOWN_VALUE;
+  }
+
+  @Override
+  public BoolState lessThanOrEqual(InstanceState rightOperand) throws EvaluationException {
+    assertNumOrNull(rightOperand);
+    return BoolState.UNKNOWN_VALUE;
+  }
+
+  @Override
+  public NumState minus(InstanceState rightOperand) throws EvaluationException {
+    assertNumOrNull(rightOperand);
+    return UNKNOWN_VALUE;
+  }
+
+  @Override
+  public NumState negated() throws EvaluationException {
+    return UNKNOWN_VALUE;
+  }
+
+  @Override
+  public NumState remainder(InstanceState rightOperand) throws EvaluationException {
+    assertNumOrNull(rightOperand);
+    return UNKNOWN_VALUE;
+  }
+
+  @Override
+  public NumState times(InstanceState rightOperand) throws EvaluationException {
+    assertNumOrNull(rightOperand);
+    return UNKNOWN_VALUE;
+  }
+
+  @Override
+  public String toString() {
+    return "-unknown-";
+  }
+}