editor/tools/plugins/com.google.dart.engine/src/com/google/dart/engine/internal/constant/ConstantVisitor.java - Issue 113143004: Constant evaluation support

Unified Diff: editor/tools/plugins/com.google.dart.engine/src/com/google/dart/engine/internal/constant/ConstantVisitor.java

Issue 113143004: Constant evaluation support (Closed) Base URL: https://dart.googlecode.com/svn/branches/bleeding_edge/dart

Patch Set: Clean-up Created 7 years ago

Use n/p to move between diff chunks; N/P to move between comments. Draft comments are only viewable by you.

Jump to:

View side-by-side diff with in-line comments

Download patch

« no previous file with comments | « editor/tools/plugins/com.google.dart.engine/src/com/google/dart/engine/internal/constant/ConstantValueComputer.java ('k') | editor/tools/plugins/com.google.dart.engine/src/com/google/dart/engine/internal/constant/ErrorResult.java » ('j') | no next file with comments »
Expand Comments ('e') | Collapse Comments ('c') | Hide Comments ('s')

Index: editor/tools/plugins/com.google.dart.engine/src/com/google/dart/engine/internal/constant/ConstantVisitor.java

diff --git a/editor/tools/plugins/com.google.dart.engine/src/com/google/dart/engine/internal/constant/ConstantVisitor.java b/editor/tools/plugins/com.google.dart.engine/src/com/google/dart/engine/internal/constant/ConstantVisitor.java

index 175a74470050d3eb87ee4cdf456bd6d28e092cb3..9253d8569953a58ceee5372dca61c73940dfdb52 100644

--- a/editor/tools/plugins/com.google.dart.engine/src/com/google/dart/engine/internal/constant/ConstantVisitor.java

+++ b/editor/tools/plugins/com.google.dart.engine/src/com/google/dart/engine/internal/constant/ConstantVisitor.java

@@ -47,15 +47,37 @@ import com.google.dart.engine.element.CompilationUnitElement;

import com.google.dart.engine.element.ConstructorElement;

import com.google.dart.engine.element.Element;

import com.google.dart.engine.element.ExecutableElement;

+import com.google.dart.engine.element.FieldFormalParameterElement;

import com.google.dart.engine.element.FunctionElement;

import com.google.dart.engine.element.FunctionTypeAliasElement;

import com.google.dart.engine.element.LibraryElement;

+import com.google.dart.engine.element.ParameterElement;

import com.google.dart.engine.element.PrefixElement;

import com.google.dart.engine.element.PropertyAccessorElement;

import com.google.dart.engine.error.CompileTimeErrorCode;

import com.google.dart.engine.error.ErrorCode;

import com.google.dart.engine.internal.element.VariableElementImpl;

+import com.google.dart.engine.internal.object.BoolState;

+import com.google.dart.engine.internal.object.DartObjectImpl;

+import com.google.dart.engine.internal.object.DoubleState;

+import com.google.dart.engine.internal.object.FunctionState;

+import com.google.dart.engine.internal.object.GenericState;

+import com.google.dart.engine.internal.object.InstanceState;

+import com.google.dart.engine.internal.object.IntState;

+import com.google.dart.engine.internal.object.ListState;

+import com.google.dart.engine.internal.object.MapState;

+import com.google.dart.engine.internal.object.NullState;

+import com.google.dart.engine.internal.object.StringState;

+import com.google.dart.engine.internal.object.SymbolState;

+import com.google.dart.engine.internal.object.TypeState;

+import com.google.dart.engine.internal.resolver.TypeProvider;

+import com.google.dart.engine.scanner.Token;

import com.google.dart.engine.scanner.TokenType;

+import com.google.dart.engine.type.InterfaceType;

+import com.google.dart.engine.utilities.dart.ParameterKind;

+import java.util.ArrayList;

+import java.util.HashMap;

/**

* Instances of the class {@code ConstantVisitor} evaluate constant expressions to produce their

@@ -65,37 +87,61 @@ import com.google.dart.engine.scanner.TokenType;

* <li>A literal number.</li>

* <li>A literal boolean.</li>

* <li>A literal string where any interpolated expression is a compile-time constant that evaluates

- * to a numeric, string or boolean value or to {@code null}.</li>

- * <li>{@code null}.</li>

- * <li>A reference to a static constant variable.</li>

- * <li>An identifier expression that denotes a constant variable, a class or a type parameter.</li>

+ * to a numeric, string or boolean value or to null.</li>

+ * <li>A literal symbol.</li>

+ * <li>null.</li>

+ * <li>A qualified reference to a static constant variable.</li>

+ * <li>An identifier expression that denotes a constant variable, class or type alias.</li>

* <li>A constant constructor invocation.</li>

* <li>A constant list literal.</li>

* <li>A constant map literal.</li>

* <li>A simple or qualified identifier denoting a top-level function or a static method.</li>

- * <li>A parenthesized expression {@code (e)} where {@code e} is a constant expression.</li>

- * <li>An expression of one of the forms {@code identical(e1, e2)}, {@code e1 == e2},

- * {@code e1 != e2} where {@code e1} and {@code e2} are constant expressions that evaluate to a

- * numeric, string or boolean value or to {@code null}.</li>

- * <li>An expression of one of the forms {@code !e}, {@code e1 && e2} or {@code e1 || e2}, where

- * {@code e}, {@code e1} and {@code e2} are constant expressions that evaluate to a boolean value or

- * to {@code null}.</li>

- * <li>An expression of one of the forms {@code ~e}, {@code e1 ^ e2}, {@code e1 & e2},

- * {@code e1 | e2}, {@code e1 >> e2} or {@code e1 << e2}, where {@code e}, {@code e1} and {@code e2}

- * are constant expressions that evaluate to an integer value or to {@code null}.</li>

- * <li>An expression of one of the forms {@code -e}, {@code e1 + e2}, {@code e1 - e2},

- * {@code e1 * e2}, {@code e1 / e2}, {@code e1 ~/ e2}, {@code e1 > e2}, {@code e1 < e2},

- * {@code e1 >= e2}, {@code e1 <= e2} or {@code e1 % e2}, where {@code e}, {@code e1} and {@code e2}

- * are constant expressions that evaluate to a numeric value or to {@code null}.</li>

+ * <li>A parenthesized expression (e) where e is a constant expression.</li>

+ * <li>An expression of the form identical(e1, e2) where

+ * e1 and e2 are constant expressions and identical() is

+ * statically bound to the predefined dart function identical() discussed above.</li>

+ * <li>An expression of one of the forms e1 == e2 or e1

+ * != e2 where e1 and e2 are constant expressions

+ * that evaluate to a numeric, string or boolean value.</li>

+ * <li>An expression of one of the forms !e, e1 && e2 or

+ * e1 || e2, where e, e1 and e2 are

+ * constant expressions that evaluate to a boolean value.</li>

+ * <li>An expression of one of the forms ~e, e1 ^ e2,

+ * e1 & e2, e1 | e2, e1

+ * >> e2 or e1 << e2, where e,

+ * e1 and e2 are constant expressions that evaluate to an

+ * integer value or to null.</li>

+ * <li>An expression of one of the forms -e, e1 + e2,

+ * e1 - e2, e1 * e2, e1 /

+ * e2, e1 ~/ e2, e1 >

+ * e2, e1 < e2, e1 >=

+ * e2, e1 <= e2 or e1 %

+ * e2, where e, e1 and e2 are constant

+ * expressions that evaluate to a numeric value or to null.</li>

+ * <li>An expression of the form e1 ? e2 : e3 where

+ * e1, e2 and e3 are constant expressions, and

+ * e1 evaluates to a boolean value.</li>

* </ul>

* </blockquote>

public class ConstantVisitor extends UnifyingASTVisitor<EvaluationResultImpl> {

/**

+ * The type provider used to access the known types.

+ */

+ private TypeProvider typeProvider;

+ /**

+ * An shared object representing the value 'null'.

+ */

+ private DartObjectImpl nullObject;

+ /**

* Initialize a newly created constant visitor.

+ *

+ * @param typeProvider the type provider used to access known types

- public ConstantVisitor() {

- super();

+ public ConstantVisitor(TypeProvider typeProvider) {

+ this.typeProvider = typeProvider;

}

@Override

@@ -105,7 +151,7 @@ public class ConstantVisitor extends UnifyingASTVisitor<EvaluationResultImpl> {

if (result == null) {

result = string.accept(this);

} else {

- result = result.concatenate(node, string.accept(this));

+ result = result.concatenate(typeProvider, node, string.accept(this));

}

return result;

@@ -126,43 +172,43 @@ public class ConstantVisitor extends UnifyingASTVisitor<EvaluationResultImpl> {

// evaluate operator

switch (operatorType) {

case AMPERSAND:

- return leftResult.bitAnd(node, rightResult);

+ return leftResult.bitAnd(typeProvider, node, rightResult);

case AMPERSAND_AMPERSAND:

- return leftResult.logicalAnd(node, rightResult);

+ return leftResult.logicalAnd(typeProvider, node, rightResult);

case BANG_EQ:

- return leftResult.notEqual(node, rightResult);

+ return leftResult.notEqual(typeProvider, node, rightResult);

case BAR:

- return leftResult.bitOr(node, rightResult);

+ return leftResult.bitOr(typeProvider, node, rightResult);

case BAR_BAR:

- return leftResult.logicalOr(node, rightResult);

+ return leftResult.logicalOr(typeProvider, node, rightResult);

case CARET:

- return leftResult.bitXor(node, rightResult);

+ return leftResult.bitXor(typeProvider, node, rightResult);

case EQ_EQ:

- return leftResult.equalEqual(node, rightResult);

+ return leftResult.equalEqual(typeProvider, node, rightResult);

case GT:

- return leftResult.greaterThan(node, rightResult);

+ return leftResult.greaterThan(typeProvider, node, rightResult);

case GT_EQ:

- return leftResult.greaterThanOrEqual(node, rightResult);

+ return leftResult.greaterThanOrEqual(typeProvider, node, rightResult);

case GT_GT:

- return leftResult.shiftRight(node, rightResult);

+ return leftResult.shiftRight(typeProvider, node, rightResult);

case LT:

- return leftResult.lessThan(node, rightResult);

+ return leftResult.lessThan(typeProvider, node, rightResult);

case LT_EQ:

- return leftResult.lessThanOrEqual(node, rightResult);

+ return leftResult.lessThanOrEqual(typeProvider, node, rightResult);

case LT_LT:

- return leftResult.shiftLeft(node, rightResult);

+ return leftResult.shiftLeft(typeProvider, node, rightResult);

case MINUS:

- return leftResult.minus(node, rightResult);

+ return leftResult.minus(typeProvider, node, rightResult);

case PERCENT:

- return leftResult.remainder(node, rightResult);

+ return leftResult.remainder(typeProvider, node, rightResult);

case PLUS:

- return leftResult.add(node, rightResult);

+ return leftResult.add(typeProvider, node, rightResult);

case STAR:

- return leftResult.times(node, rightResult);

+ return leftResult.times(typeProvider, node, rightResult);

case SLASH:

- return leftResult.divide(node, rightResult);

+ return leftResult.divide(typeProvider, node, rightResult);

case TILDE_SLASH:

- return leftResult.integerDivide(node, rightResult);

+ return leftResult.integerDivide(typeProvider, node, rightResult);

}

// TODO(brianwilkerson) Figure out which error to report.

return error(node, null);

@@ -170,31 +216,42 @@ public class ConstantVisitor extends UnifyingASTVisitor<EvaluationResultImpl> {

@Override

public EvaluationResultImpl visitBooleanLiteral(BooleanLiteral node) {

- return node.getValue() ? ValidResult.RESULT_TRUE : ValidResult.RESULT_FALSE;

+ return valid(typeProvider.getBoolType(), BoolState.from(node.getValue()));

}

@Override

public EvaluationResultImpl visitConditionalExpression(ConditionalExpression node) {

Expression condition = node.getCondition();

EvaluationResultImpl conditionResult = condition.accept(this);

- conditionResult = conditionResult.applyBooleanConversion(condition);

+ EvaluationResultImpl thenResult = node.getThenExpression().accept(this);

+ EvaluationResultImpl elseResult = node.getElseExpression().accept(this);

+ if (conditionResult instanceof ErrorResult) {

+ return union(union((ErrorResult) conditionResult, thenResult), elseResult);

+ } else if (!((ValidResult) conditionResult).isBool()) {

+ return new ErrorResult(condition, CompileTimeErrorCode.CONST_EVAL_TYPE_BOOL);

+ } else if (thenResult instanceof ErrorResult) {

+ return union((ErrorResult) thenResult, elseResult);

+ } else if (elseResult instanceof ErrorResult) {

+ return elseResult;

+ }

+ conditionResult = conditionResult.applyBooleanConversion(typeProvider, condition);

if (conditionResult instanceof ErrorResult) {

return conditionResult;

}

- EvaluationResultImpl thenResult = node.getThenExpression().accept(this);

- if (thenResult instanceof ErrorResult) {

+ ValidResult validResult = (ValidResult) conditionResult;

+ if (validResult.isTrue()) {

return thenResult;

- }

- EvaluationResultImpl elseResult = node.getElseExpression().accept(this);

- if (elseResult instanceof ErrorResult) {

+ } else if (validResult.isFalse()) {

return elseResult;

}

- return (conditionResult == ValidResult.RESULT_TRUE) ? thenResult : elseResult;

+ InterfaceType thenType = ((ValidResult) thenResult).getValue().getType();

+ InterfaceType elseType = ((ValidResult) elseResult).getValue().getType();

+ return valid((InterfaceType) thenType.getLeastUpperBound(elseType));

}

@Override

public EvaluationResultImpl visitDoubleLiteral(DoubleLiteral node) {

- return new ValidResult(Double.valueOf(node.getValue()));

+ return valid(typeProvider.getDoubleType(), new DoubleState(node.getValue()));

}

@Override

@@ -205,8 +262,54 @@ public class ConstantVisitor extends UnifyingASTVisitor<EvaluationResultImpl> {

}

ConstructorElement constructor = node.getStaticElement();

if (constructor != null && constructor.isConst()) {

- node.getArgumentList().accept(this);

- return ValidResult.RESULT_OBJECT;

+ NodeList<Expression> arguments = node.getArgumentList().getArguments();

+ int argumentCount = arguments.size();

+ DartObjectImpl[] argumentValues = new DartObjectImpl[argumentCount];

+ HashMap<String, DartObjectImpl> namedArgumentValues = new HashMap<String, DartObjectImpl>();

+ for (int i = 0; i < argumentCount; i++) {

+ Expression argument = arguments.get(i);

+ if (argument instanceof NamedExpression) {

+ NamedExpression namedExpression = (NamedExpression) argument;

+ String name = namedExpression.getName().getLabel().getName();

+ namedArgumentValues.put(name, valueOf(namedExpression.getExpression()));

+ argumentValues[i] = getNull();

+ } else {

+ argumentValues[i] = valueOf(argument);

+ }

+ InterfaceType definingClass = (InterfaceType) constructor.getReturnType();

+ if (definingClass.getElement().getLibrary().isDartCore()) {

+ String className = definingClass.getName();

+ if (className.equals("Symbol") && argumentCount == 1) {

+ String argumentValue = argumentValues[0].getStringValue();

+ if (argumentValue != null) {

+ return valid(definingClass, new SymbolState(argumentValue));

+ }

+ HashMap<String, DartObjectImpl> fieldMap = new HashMap<String, DartObjectImpl>();

+ ParameterElement[] parameters = constructor.getParameters();

+ int parameterCount = parameters.length;

+ for (int i = 0; i < parameterCount; i++) {

+ ParameterElement parameter = parameters[i];

+ if (parameter.isInitializingFormal()) {

+ String fieldName = ((FieldFormalParameterElement) parameter).getField().getName();

+ if (parameter.getParameterKind() == ParameterKind.NAMED) {

+ DartObjectImpl argumentValue = namedArgumentValues.get(parameter.getName());

+ if (argumentValue != null) {

+ fieldMap.put(fieldName, argumentValue);

+ }

+ } else if (i < argumentCount) {

+ fieldMap.put(fieldName, argumentValues[i]);

+ // Otherwise, the parameter is assumed to be an optional positional parameter for which

+ // no value was provided.

+ }

+ // TODO(brianwilkerson) This doesn't handle fields initialized in an initializer. We should be

+ // able to handle fields initialized by the superclass' constructor fairly easily, but other

+ // initializers will be harder.

+ return valid(definingClass, new GenericState(fieldMap));

}

// TODO(brianwilkerson) Figure out which error to report.

return error(node, null);

@@ -214,18 +317,21 @@ public class ConstantVisitor extends UnifyingASTVisitor<EvaluationResultImpl> {

@Override

public EvaluationResultImpl visitIntegerLiteral(IntegerLiteral node) {

- return new ValidResult(node.getValue());

+ return valid(typeProvider.getIntType(), new IntState(node.getValue()));

}

@Override

public EvaluationResultImpl visitInterpolationExpression(InterpolationExpression node) {

EvaluationResultImpl result = node.getExpression().accept(this);

- return result.performToString(node);

+ if (result instanceof ValidResult && !((ValidResult) result).isBoolNumStringOrNull()) {

+ return error(node, CompileTimeErrorCode.CONST_EVAL_TYPE_BOOL_NUM_STRING);

+ }

+ return result.performToString(typeProvider, node);

}

@Override

public EvaluationResultImpl visitInterpolationString(InterpolationString node) {

- return new ValidResult(node.getValue());

+ return valid(typeProvider.getStringType(), new StringState(node.getValue()));

}

@Override

@@ -234,13 +340,20 @@ public class ConstantVisitor extends UnifyingASTVisitor<EvaluationResultImpl> {

return new ErrorResult(node, CompileTimeErrorCode.MISSING_CONST_IN_LIST_LITERAL);

}

ErrorResult result = null;

+ ArrayList<DartObjectImpl> elements = new ArrayList<DartObjectImpl>();

for (Expression element : node.getElements()) {

- result = union(result, element.accept(this));

+ EvaluationResultImpl elementResult = element.accept(this);

+ result = union(result, elementResult);

+ if (elementResult instanceof ValidResult) {

+ elements.add(((ValidResult) elementResult).getValue());

+ }

}

if (result != null) {

return result;

}

- return ValidResult.RESULT_OBJECT;

+ return valid(

+ typeProvider.getListType(),

+ new ListState(elements.toArray(new DartObjectImpl[elements.size()])));

}

@Override

@@ -249,14 +362,20 @@ public class ConstantVisitor extends UnifyingASTVisitor<EvaluationResultImpl> {

return new ErrorResult(node, CompileTimeErrorCode.MISSING_CONST_IN_MAP_LITERAL);

}

ErrorResult result = null;

+ HashMap<DartObjectImpl, DartObjectImpl> map = new HashMap<DartObjectImpl, DartObjectImpl>();

for (MapLiteralEntry entry : node.getEntries()) {

- result = union(result, entry.getKey().accept(this));

- result = union(result, entry.getValue().accept(this));

+ EvaluationResultImpl keyResult = entry.getKey().accept(this);

+ EvaluationResultImpl valueResult = entry.getValue().accept(this);

+ result = union(result, keyResult);

+ result = union(result, valueResult);

+ if (keyResult instanceof ValidResult && valueResult instanceof ValidResult) {

+ map.put(((ValidResult) keyResult).getValue(), ((ValidResult) valueResult).getValue());

+ }

}

if (result != null) {

return result;

}

- return ValidResult.RESULT_OBJECT;

+ return valid(typeProvider.getMapType(), new MapState(map));

}

@Override

@@ -273,7 +392,7 @@ public class ConstantVisitor extends UnifyingASTVisitor<EvaluationResultImpl> {

if (library.isDartCore()) {

EvaluationResultImpl leftArgument = arguments.get(0).accept(this);

EvaluationResultImpl rightArgument = arguments.get(1).accept(this);

- return leftArgument.equalEqual(node, rightArgument);

+ return leftArgument.equalEqual(typeProvider, node, rightArgument);

}

@@ -296,7 +415,7 @@ public class ConstantVisitor extends UnifyingASTVisitor<EvaluationResultImpl> {

@Override

public EvaluationResultImpl visitNullLiteral(NullLiteral node) {

- return ValidResult.RESULT_NULL;

+ return new ValidResult(getNull());

}

@Override

@@ -327,11 +446,11 @@ public class ConstantVisitor extends UnifyingASTVisitor<EvaluationResultImpl> {

}

switch (node.getOperator().getType()) {

case BANG:

- return operand.logicalNot(node);

+ return operand.logicalNot(typeProvider, node);

case TILDE:

- return operand.bitNot(node);

+ return operand.bitNot(typeProvider, node);

case MINUS:

- return operand.negated(node);

+ return operand.negated(typeProvider, node);

}

// TODO(brianwilkerson) Figure out which error to report.

return error(node, null);

@@ -349,7 +468,7 @@ public class ConstantVisitor extends UnifyingASTVisitor<EvaluationResultImpl> {

@Override

public EvaluationResultImpl visitSimpleStringLiteral(SimpleStringLiteral node) {

- return new ValidResult(node.getValue());

+ return valid(typeProvider.getStringType(), new StringState(node.getValue()));

}

@Override

@@ -359,7 +478,7 @@ public class ConstantVisitor extends UnifyingASTVisitor<EvaluationResultImpl> {

if (result == null) {

result = element.accept(this);

} else {

- result = result.concatenate(node, element.accept(this));

+ result = result.concatenate(typeProvider, node, element.accept(this));

}

return result;

@@ -367,7 +486,15 @@ public class ConstantVisitor extends UnifyingASTVisitor<EvaluationResultImpl> {

@Override

public EvaluationResultImpl visitSymbolLiteral(SymbolLiteral node) {

- return ValidResult.RESULT_SYMBOL;

+ StringBuilder builder = new StringBuilder();

+ Token[] components = node.getComponents();

+ for (int i = 0; i < components.length; i++) {

+ if (i > 0) {

+ builder.append('.');

+ }

+ builder.append(components[i].getLexeme());

+ }

+ return valid(typeProvider.getSymbolType(), new SymbolState(builder.toString()));

}

/**

@@ -399,17 +526,30 @@ public class ConstantVisitor extends UnifyingASTVisitor<EvaluationResultImpl> {

return value;

}

} else if (element instanceof ExecutableElement) {

- if (((ExecutableElement) element).isStatic()) {

- return new ValidResult(element);

+ ExecutableElement function = (ExecutableElement) element;

+ if (function.isStatic()) {

+ return valid(typeProvider.getFunctionType(), new FunctionState(function));

}

} else if (element instanceof ClassElement || element instanceof FunctionTypeAliasElement) {

- return ValidResult.RESULT_OBJECT;

+ return valid(typeProvider.getTypeType(), new TypeState(element));

}

// TODO(brianwilkerson) Figure out which error to report.

return error(node, null);

}

/**

+ * Return an object representing the value 'null'.

+ *

+ * @return an object representing the value 'null'

+ */

+ private DartObjectImpl getNull() {

+ if (nullObject == null) {

+ nullObject = new DartObjectImpl(typeProvider.getNullType(), NullState.NULL_STATE);

+ }

+ return nullObject;

+ }

+ /**

* Return the union of the errors encoded in the given results.

* @param leftResult the first set of errors, or {@code null} if there was no previous collection

@@ -428,4 +568,39 @@ public class ConstantVisitor extends UnifyingASTVisitor<EvaluationResultImpl> {

}

return leftResult;

}

+ private ValidResult valid(InterfaceType type) {

+ if (type.getElement().getLibrary().isDartCore()) {

+ String typeName = type.getName();

+ if (typeName.equals("bool")) {

+ return valid(type, BoolState.UNKNOWN_VALUE);

+ } else if (typeName.equals("double")) {

+ return valid(type, DoubleState.UNKNOWN_VALUE);

+ } else if (typeName.equals("int")) {

+ return valid(type, IntState.UNKNOWN_VALUE);

+ } else if (typeName.equals("String")) {

+ return valid(type, StringState.UNKNOWN_VALUE);

+ }

+ return valid(type, GenericState.UNKNOWN_VALUE);

+ }

+ private ValidResult valid(InterfaceType type, InstanceState state) {

+ return new ValidResult(new DartObjectImpl(type, state));

+ }

+ /**

+ * Return the value of the given expression, or a representation of 'null' if the expression

+ * cannot be evaluated.

+ *

+ * @param expression the expression whose value is to be returned

+ * @return the value of the given expression

+ */

+ private DartObjectImpl valueOf(Expression expression) {

+ EvaluationResultImpl expressionValue = expression.accept(this);

+ if (expressionValue instanceof ValidResult) {

+ return ((ValidResult) expressionValue).getValue();

+ }

+ return getNull();

+ }

}