/*
* Copyright 2006 The Closure Compiler Authors.
*
* Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
*
* 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.javascript.jscomp;
import static com.google.javascript.rhino.jstype.JSTypeNative.ARRAY_TYPE;
import static com.google.javascript.rhino.jstype.JSTypeNative.BOOLEAN_TYPE;
import static com.google.javascript.rhino.jstype.JSTypeNative.NULL_TYPE;
import static com.google.javascript.rhino.jstype.JSTypeNative.NUMBER_TYPE;
import static com.google.javascript.rhino.jstype.JSTypeNative.OBJECT_FUNCTION_TYPE;
import static com.google.javascript.rhino.jstype.JSTypeNative.OBJECT_TYPE;
import static com.google.javascript.rhino.jstype.JSTypeNative.REGEXP_TYPE;
import static com.google.javascript.rhino.jstype.JSTypeNative.STRING_TYPE;
import static com.google.javascript.rhino.jstype.JSTypeNative.UNKNOWN_TYPE;
import static com.google.javascript.rhino.jstype.JSTypeNative.VOID_TYPE;
import com.google.common.base.Preconditions;
import com.google.javascript.jscomp.CheckLevel;
import com.google.javascript.jscomp.Scope.Var;
import com.google.javascript.rhino.JSDocInfo;
import com.google.javascript.rhino.Node;
import com.google.javascript.rhino.Token;
import com.google.javascript.rhino.jstype.EnumType;
import com.google.javascript.rhino.jstype.FunctionType;
import com.google.javascript.rhino.jstype.JSType;
import com.google.javascript.rhino.jstype.JSTypeNative;
import com.google.javascript.rhino.jstype.JSTypeRegistry;
import com.google.javascript.rhino.jstype.ObjectType;
import com.google.javascript.rhino.jstype.TernaryValue;
import java.util.Iterator;
import java.util.Set;
import java.util.HashMap;
/**
* <p>Checks the types of JS expressions against any declared type
* information.</p>
*
*/
public class TypeCheck implements NodeTraversal.Callback, CompilerPass {
//
// Internal errors
//
static final DiagnosticType UNEXPECTED_TOKEN = DiagnosticType.error(
"JSC_INTERNAL_ERROR_UNEXPECTED_TOKEN",
"Internal Error: Don't know how to handle {0}");
//
// User errors
//
// TODO(nicksantos): delete this
static final DiagnosticType BAD_DELETE =
DiagnosticType.warning(
"JSC_BAD_DELETE_OPERAND",
"delete operator needs a reference operand");
//
// User warnings
//
protected static final String OVERRIDING_PROTOTYPE_WITH_NON_OBJECT =
"overriding prototype with non-object";
// TODO(user): make all the non private messages private once the
// TypedScopeCreator has been merged with the type checker.
static final DiagnosticType DETERMINISTIC_TEST =
DiagnosticType.warning(
"JSC_DETERMINISTIC_TEST",
"condition always evaluates to {2}\n" +
"left : {0}\n" +
"right: {1}");
static final DiagnosticType DETERMINISTIC_TEST_NO_RESULT =
DiagnosticType.warning(
"JSC_DETERMINISTIC_TEST_NO_RESULT",
"condition always evaluates to the same value\n" +
"left : {0}\n" +
"right: {1}");
static final DiagnosticType INEXISTENT_ENUM_ELEMENT =
DiagnosticType.warning(
"JSC_INEXISTENT_ENUM_ELEMENT",
"element {0} does not exist on this enum");
// disabled by default. This one only makes sense if you're using
// well-typed externs.
static final DiagnosticType INEXISTENT_PROPERTY =
DiagnosticType.disabled(
"JSC_INEXISTENT_PROPERTY",
"Property {0} never defined on {1}");
protected static final DiagnosticType NOT_A_CONSTRUCTOR =
DiagnosticType.warning(
"JSC_NOT_A_CONSTRUCTOR",
"cannot instantiate non-constructor");
static final DiagnosticType BIT_OPERATION =
DiagnosticType.warning(
"JSC_BAD_TYPE_FOR_BIT_OPERATION",
"operator {0} cannot be applied to {1}");
static final DiagnosticType NOT_CALLABLE =
DiagnosticType.warning(
"JSC_NOT_FUNCTION_TYPE",
"{0} expressions are not callable");
static final DiagnosticType CONSTRUCTOR_NOT_CALLABLE =
DiagnosticType.warning(
"JSC_CONSTRUCTOR_NOT_CALLABLE",
"Constructor {0} should be called with the \"new\" keyword");
static final DiagnosticType FUNCTION_MASKS_VARIABLE =
DiagnosticType.warning(
"JSC_FUNCTION_MASKS_VARIABLE",
"function {0} masks variable (IE bug)");
static final DiagnosticType MULTIPLE_VAR_DEF = DiagnosticType.warning(
"JSC_MULTIPLE_VAR_DEF",
"declaration of multiple variables with shared type information");
static final DiagnosticType ENUM_DUP = DiagnosticType.error("JSC_ENUM_DUP",
"enum element {0} already defined");
static final DiagnosticType ENUM_NOT_CONSTANT =
DiagnosticType.warning("JSC_ENUM_NOT_CONSTANT",
"enum key {0} must be a syntactic constant");
static final DiagnosticType INVALID_INTERFACE_MEMBER_DECLARATION =
DiagnosticType.warning(
"JSC_INVALID_INTERFACE_MEMBER_DECLARATION",
"interface members can only be empty property declarations,"
+ " empty functions{0}");
static final DiagnosticType INTERFACE_FUNCTION_NOT_EMPTY =
DiagnosticType.warning(
"JSC_INTERFACE_FUNCTION_NOT_EMPTY",
"interface member functions must have an empty body");
static final DiagnosticType CONFLICTING_EXTENDED_TYPE =
DiagnosticType.warning(
"JSC_CONFLICTING_EXTENDED_TYPE",
"{0} cannot extend this type; " +
"a constructor can only extend objects " +
"and an interface can only extend interfaces");
static final DiagnosticType CONFLICTING_IMPLEMENTED_TYPE =
DiagnosticType.warning(
"JSC_CONFLICTING_IMPLEMENTED_TYPE",
"{0} cannot implement this type; " +
"an interface can only extend, but not implement interfaces");
static final DiagnosticType BAD_IMPLEMENTED_TYPE =
DiagnosticType.warning(
"JSC_IMPLEMENTS_NON_INTERFACE",
"can only implement interfaces");
static final DiagnosticType HIDDEN_SUPERCLASS_PROPERTY =
DiagnosticType.warning(
"JSC_HIDDEN_SUPERCLASS_PROPERTY",
"property {0} already defined on superclass {1}; " +
"use @override to override it");
static final DiagnosticType HIDDEN_INTERFACE_PROPERTY =
DiagnosticType.warning(
"JSC_HIDDEN_INTERFACE_PROPERTY",
"property {0} already defined on interface {1}; " +
"use @override to override it");
static final DiagnosticType HIDDEN_SUPERCLASS_PROPERTY_MISMATCH =
DiagnosticType.warning("JSC_HIDDEN_SUPERCLASS_PROPERTY_MISMATCH",
"mismatch of the {0} property type and the type " +
"of the property it overrides from superclass {1}\n" +
"original: {2}\n" +
"override: {3}");
static final DiagnosticType UNKNOWN_OVERRIDE =
DiagnosticType.warning(
"JSC_UNKNOWN_OVERRIDE",
"property {0} not defined on any superclass of {1}");
static final DiagnosticType INTERFACE_METHOD_OVERRIDE =
DiagnosticType.warning(
"JSC_INTERFACE_METHOD_OVERRIDE",
"property {0} is already defined by the {1} extended interface");
static final DiagnosticType UNKNOWN_EXPR_TYPE =
DiagnosticType.warning("JSC_UNKNOWN_EXPR_TYPE",
"could not determine the type of this expression");
static final DiagnosticType UNRESOLVED_TYPE =
DiagnosticType.warning("JSC_UNRESOLVED_TYPE",
"could not resolve the name {0} to a type");
static final DiagnosticType WRONG_ARGUMENT_COUNT =
DiagnosticType.warning(
"JSC_WRONG_ARGUMENT_COUNT",
"Function {0}: called with {1} argument(s). " +
"Function requires at least {2} argument(s){3}.");
static final DiagnosticType ILLEGAL_IMPLICIT_CAST =
DiagnosticType.warning(
"JSC_ILLEGAL_IMPLICIT_CAST",
"Illegal annotation on {0}. @implicitCast may only be used in " +
"externs.");
static final DiagnosticType INCOMPATIBLE_EXTENDED_PROPERTY_TYPE =
DiagnosticType.warning(
"JSC_INCOMPATIBLE_EXTENDED_PROPERTY_TYPE",
"Interface {0} has a property {1} with incompatible types in " +
"its super interfaces {2} and {3}");
static final DiagnosticType EXPECTED_THIS_TYPE =
DiagnosticType.warning(
"JSC_EXPECTED_THIS_TYPE",
"\"{0}\" must be called with a \"this\" type");
static final DiagnosticGroup ALL_DIAGNOSTICS = new DiagnosticGroup(
DETERMINISTIC_TEST,
DETERMINISTIC_TEST_NO_RESULT,
INEXISTENT_ENUM_ELEMENT,
INEXISTENT_PROPERTY,
NOT_A_CONSTRUCTOR,
BIT_OPERATION,
NOT_CALLABLE,
CONSTRUCTOR_NOT_CALLABLE,
FUNCTION_MASKS_VARIABLE,
MULTIPLE_VAR_DEF,
ENUM_DUP,
ENUM_NOT_CONSTANT,
INVALID_INTERFACE_MEMBER_DECLARATION,
INTERFACE_FUNCTION_NOT_EMPTY,
CONFLICTING_EXTENDED_TYPE,
CONFLICTING_IMPLEMENTED_TYPE,
BAD_IMPLEMENTED_TYPE,
HIDDEN_SUPERCLASS_PROPERTY,
HIDDEN_INTERFACE_PROPERTY,
HIDDEN_SUPERCLASS_PROPERTY_MISMATCH,
UNKNOWN_OVERRIDE,
INTERFACE_METHOD_OVERRIDE,
UNKNOWN_EXPR_TYPE,
UNRESOLVED_TYPE,
WRONG_ARGUMENT_COUNT,
ILLEGAL_IMPLICIT_CAST,
INCOMPATIBLE_EXTENDED_PROPERTY_TYPE,
EXPECTED_THIS_TYPE,
RhinoErrorReporter.TYPE_PARSE_ERROR,
TypedScopeCreator.UNKNOWN_LENDS,
TypedScopeCreator.LENDS_ON_NON_OBJECT,
TypedScopeCreator.CTOR_INITIALIZER,
TypedScopeCreator.IFACE_INITIALIZER,
FunctionTypeBuilder.THIS_TYPE_NON_OBJECT);
private final AbstractCompiler compiler;
private final TypeValidator validator;
private final ReverseAbstractInterpreter reverseInterpreter;
private final JSTypeRegistry typeRegistry;
private Scope topScope;
private ScopeCreator scopeCreator;
private final CheckLevel reportMissingOverride;
private final CheckLevel reportUnknownTypes;
// This may be expensive, so don't emit these warnings if they're
// explicitly turned off.
private boolean reportMissingProperties = true;
private InferJSDocInfo inferJSDocInfo = null;
// These fields are used to calculate the percentage of expressions typed.
private int typedCount = 0;
private int nullCount = 0;
private int unknownCount = 0;
private boolean inExterns;
// A state boolean to see we are currently in @notypecheck section of the
// code.
private int noTypeCheckSection = 0;
public TypeCheck(AbstractCompiler compiler,
ReverseAbstractInterpreter reverseInterpreter,
JSTypeRegistry typeRegistry,
Scope topScope,
ScopeCreator scopeCreator,
CheckLevel reportMissingOverride,
CheckLevel reportUnknownTypes) {
this.compiler = compiler;
this.validator = compiler.getTypeValidator();
this.reverseInterpreter = reverseInterpreter;
this.typeRegistry = typeRegistry;
this.topScope = topScope;
this.scopeCreator = scopeCreator;
this.reportMissingOverride = reportMissingOverride;
this.reportUnknownTypes = reportUnknownTypes;
this.inferJSDocInfo = new InferJSDocInfo(compiler);
}
public TypeCheck(AbstractCompiler compiler,
ReverseAbstractInterpreter reverseInterpreter,
JSTypeRegistry typeRegistry,
CheckLevel reportMissingOverride,
CheckLevel reportUnknownTypes) {
this(compiler, reverseInterpreter, typeRegistry, null, null,
reportMissingOverride, reportUnknownTypes);
}
TypeCheck(AbstractCompiler compiler,
ReverseAbstractInterpreter reverseInterpreter,
JSTypeRegistry typeRegistry) {
this(compiler, reverseInterpreter, typeRegistry, null, null,
CheckLevel.WARNING, CheckLevel.OFF);
}
/** Turn on the missing property check. Returns this for easy chaining. */
TypeCheck reportMissingProperties(boolean report) {
reportMissingProperties = report;
return this;
}
/**
* Main entry point for this phase of processing. This follows the pattern for
* JSCompiler phases.
*
* @param externsRoot The root of the externs parse tree.
* @param jsRoot The root of the input parse tree to be checked.
*/
@Override
public void process(Node externsRoot, Node jsRoot) {
Preconditions.checkNotNull(scopeCreator);
Preconditions.checkNotNull(topScope);
Node externsAndJs = jsRoot.getParent();
Preconditions.checkState(externsAndJs != null);
Preconditions.checkState(
externsRoot == null || externsAndJs.hasChild(externsRoot));
if (externsRoot != null) {
check(externsRoot, true);
}
check(jsRoot, false);
}
/** Main entry point of this phase for testing code. */
public Scope processForTesting(Node externsRoot, Node jsRoot) {
Preconditions.checkState(scopeCreator == null);
Preconditions.checkState(topScope == null);
Preconditions.checkState(jsRoot.getParent() != null);
Node externsAndJsRoot = jsRoot.getParent();
scopeCreator = new MemoizedScopeCreator(new TypedScopeCreator(compiler));
topScope = scopeCreator.createScope(externsAndJsRoot, null);
TypeInferencePass inference = new TypeInferencePass(compiler,
reverseInterpreter, topScope, scopeCreator);
inference.process(externsRoot, jsRoot);
process(externsRoot, jsRoot);
return topScope;
}
public void check(Node node, boolean externs) {
Preconditions.checkNotNull(node);
NodeTraversal t = new NodeTraversal(compiler, this, scopeCreator);
inExterns = externs;
t.traverseWithScope(node, topScope);
if (externs) {
inferJSDocInfo.process(node, null);
} else {
inferJSDocInfo.process(null, node);
}
}
private void checkNoTypeCheckSection(Node n, boolean enterSection) {
switch (n.getType()) {
case Token.SCRIPT:
case Token.BLOCK:
case Token.VAR:
case Token.FUNCTION:
case Token.ASSIGN:
JSDocInfo info = n.getJSDocInfo();
if (info != null && info.isNoTypeCheck()) {
if (enterSection) {
noTypeCheckSection++;
} else {
noTypeCheckSection--;
}
}
validator.setShouldReport(noTypeCheckSection == 0);
break;
}
}
private void report(NodeTraversal t, Node n, DiagnosticType diagnosticType,
String... arguments) {
if (noTypeCheckSection == 0) {
t.report(n, diagnosticType, arguments);
}
}
@Override
public boolean shouldTraverse(
NodeTraversal t, Node n, Node parent) {
checkNoTypeCheckSection(n, true);
switch (n.getType()) {
case Token.FUNCTION:
// normal type checking
final Scope outerScope = t.getScope();
final String functionPrivateName = n.getFirstChild().getString();
if (functionPrivateName != null && functionPrivateName.length() > 0 &&
outerScope.isDeclared(functionPrivateName, false) &&
// Ideally, we would want to check whether the type in the scope
// differs from the type being defined, but then the extern
// redeclarations of built-in types generates spurious warnings.
!(outerScope.getVar(
functionPrivateName).getType() instanceof FunctionType)) {
report(t, n, FUNCTION_MASKS_VARIABLE, functionPrivateName);
}
// TODO(user): Only traverse the function's body. The function's
// name and arguments are traversed by the scope creator, and ideally
// should not be traversed by the type checker.
break;
}
return true;
}
/**
* This is the meat of the type checking. It is basically one big switch,
* with each case representing one type of parse tree node. The individual
* cases are usually pretty straightforward.
*
* @param t The node traversal object that supplies context, such as the
* scope chain to use in name lookups as well as error reporting.
* @param n The node being visited.
* @param parent The parent of the node n.
*/
@Override
public void visit(NodeTraversal t, Node n, Node parent) {
JSType childType;
JSType leftType, rightType;
Node left, right;
// To be explicitly set to false if the node is not typeable.
boolean typeable = true;
switch (n.getType()) {
case Token.NAME:
typeable = visitName(t, n, parent);
break;
case Token.LP:
// If this is under a FUNCTION node, it is a parameter list and can be
// ignored here.
if (parent.getType() != Token.FUNCTION) {
ensureTyped(t, n, getJSType(n.getFirstChild()));
} else {
typeable = false;
}
break;
case Token.COMMA:
ensureTyped(t, n, getJSType(n.getLastChild()));
break;
case Token.TRUE:
case Token.FALSE:
ensureTyped(t, n, BOOLEAN_TYPE);
break;
case Token.THIS:
ensureTyped(t, n, t.getScope().getTypeOfThis());
break;
case Token.REF_SPECIAL:
ensureTyped(t, n);
break;
case Token.GET_REF:
ensureTyped(t, n, getJSType(n.getFirstChild()));
break;
case Token.NULL:
ensureTyped(t, n, NULL_TYPE);
break;
case Token.NUMBER:
ensureTyped(t, n, NUMBER_TYPE);
break;
case Token.STRING:
// Object literal keys are handled with OBJECTLIT
if (!NodeUtil.isObjectLitKey(n, n.getParent())) {
ensureTyped(t, n, STRING_TYPE);
} else {
// Object literal keys are not typeable
typeable = false;
}
break;
case Token.GET:
case Token.SET:
// Object literal keys are handled with OBJECTLIT
break;
case Token.ARRAYLIT:
ensureTyped(t, n, ARRAY_TYPE);
break;
case Token.REGEXP:
ensureTyped(t, n, REGEXP_TYPE);
break;
case Token.GETPROP:
visitGetProp(t, n, parent);
typeable = !(parent.getType() == Token.ASSIGN &&
parent.getFirstChild() == n);
break;
case Token.GETELEM:
visitGetElem(t, n);
// The type of GETELEM is always unknown, so no point counting that.
// If that unknown leaks elsewhere (say by an assignment to another
// variable), then it will be counted.
typeable = false;
break;
case Token.VAR:
visitVar(t, n);
typeable = false;
break;
case Token.NEW:
visitNew(t, n);
typeable = true;
break;
case Token.CALL:
visitCall(t, n);
typeable = !NodeUtil.isExpressionNode(parent);
break;
case Token.RETURN:
visitReturn(t, n);
typeable = false;
break;
case Token.DEC:
case Token.INC:
left = n.getFirstChild();
validator.expectNumber(
t, left, getJSType(left), "increment/decrement");
ensureTyped(t, n, NUMBER_TYPE);
break;
case Token.NOT:
ensureTyped(t, n, BOOLEAN_TYPE);
break;
case Token.VOID:
ensureTyped(t, n, VOID_TYPE);
break;
case Token.TYPEOF:
ensureTyped(t, n, STRING_TYPE);
break;
case Token.BITNOT:
childType = getJSType(n.getFirstChild());
if (!childType.matchesInt32Context()) {
report(t, n, BIT_OPERATION, NodeUtil.opToStr(n.getType()),
childType.toString());
}
ensureTyped(t, n, NUMBER_TYPE);
break;
case Token.POS:
case Token.NEG:
left = n.getFirstChild();
validator.expectNumber(t, left, getJSType(left), "sign operator");
ensureTyped(t, n, NUMBER_TYPE);
break;
case Token.EQ:
case Token.NE: {
leftType = getJSType(n.getFirstChild());
rightType = getJSType(n.getLastChild());
JSType leftTypeRestricted = leftType.restrictByNotNullOrUndefined();
JSType rightTypeRestricted = rightType.restrictByNotNullOrUndefined();
TernaryValue result =
leftTypeRestricted.testForEquality(rightTypeRestricted);
if (result != TernaryValue.UNKNOWN) {
if (n.getType() == Token.NE) {
result = result.not();
}
report(t, n, DETERMINISTIC_TEST, leftType.toString(),
rightType.toString(), result.toString());
}
ensureTyped(t, n, BOOLEAN_TYPE);
break;
}
case Token.SHEQ:
case Token.SHNE: {
leftType = getJSType(n.getFirstChild());
rightType = getJSType(n.getLastChild());
JSType leftTypeRestricted = leftType.restrictByNotNullOrUndefined();
JSType rightTypeRestricted = rightType.restrictByNotNullOrUndefined();
if (!leftTypeRestricted.canTestForShallowEqualityWith(
rightTypeRestricted)) {
report(t, n, DETERMINISTIC_TEST_NO_RESULT, leftType.toString(),
rightType.toString());
}
ensureTyped(t, n, BOOLEAN_TYPE);
break;
}
case Token.LT:
case Token.LE:
case Token.GT:
case Token.GE:
leftType = getJSType(n.getFirstChild());
rightType = getJSType(n.getLastChild());
if (rightType.isNumber()) {
validator.expectNumber(
t, n, leftType, "left side of numeric comparison");
} else if (leftType.isNumber()) {
validator.expectNumber(
t, n, rightType, "right side of numeric comparison");
} else if (leftType.matchesNumberContext() &&
rightType.matchesNumberContext()) {
// OK.
} else {
// Whether the comparison is numeric will be determined at runtime
// each time the expression is evaluated. Regardless, both operands
// should match a string context.
String message = "left side of comparison";
validator.expectString(t, n, leftType, message);
validator.expectNotNullOrUndefined(
t, n, leftType, message, getNativeType(STRING_TYPE));
message = "right side of comparison";
validator.expectString(t, n, rightType, message);
validator.expectNotNullOrUndefined(
t, n, rightType, message, getNativeType(STRING_TYPE));
}
ensureTyped(t, n, BOOLEAN_TYPE);
break;
case Token.IN:
left = n.getFirstChild();
right = n.getLastChild();
leftType = getJSType(left);
rightType = getJSType(right);
validator.expectObject(t, n, rightType, "'in' requires an object");
validator.expectString(t, left, leftType, "left side of 'in'");
ensureTyped(t, n, BOOLEAN_TYPE);
break;
case Token.INSTANCEOF:
left = n.getFirstChild();
right = n.getLastChild();
leftType = getJSType(left);
rightType = getJSType(right).restrictByNotNullOrUndefined();
validator.expectAnyObject(
t, left, leftType, "deterministic instanceof yields false");
validator.expectActualObject(
t, right, rightType, "instanceof requires an object");
ensureTyped(t, n, BOOLEAN_TYPE);
break;
case Token.ASSIGN:
visitAssign(t, n);
typeable = false;
break;
case Token.ASSIGN_LSH:
case Token.ASSIGN_RSH:
case Token.ASSIGN_URSH:
case Token.ASSIGN_DIV:
case Token.ASSIGN_MOD:
case Token.ASSIGN_BITOR:
case Token.ASSIGN_BITXOR:
case Token.ASSIGN_BITAND:
case Token.ASSIGN_SUB:
case Token.ASSIGN_ADD:
case Token.ASSIGN_MUL:
case Token.LSH:
case Token.RSH:
case Token.URSH:
case Token.DIV:
case Token.MOD:
case Token.BITOR:
case Token.BITXOR:
case Token.BITAND:
case Token.SUB:
case Token.ADD:
case Token.MUL:
visitBinaryOperator(n.getType(), t, n);
break;
case Token.DELPROP:
ensureTyped(t, n, BOOLEAN_TYPE);
break;
case Token.CASE:
JSType switchType = getJSType(parent.getFirstChild());
JSType caseType = getJSType(n.getFirstChild());
validator.expectSwitchMatchesCase(t, n, switchType, caseType);
typeable = false;
break;
case Token.WITH: {
Node child = n.getFirstChild();
childType = getJSType(child);
validator.expectObject(
t, child, childType, "with requires an object");
typeable = false;
break;
}
case Token.FUNCTION:
visitFunction(t, n);
break;
// These nodes have no interesting type behavior.
case Token.LABEL:
case Token.LABEL_NAME:
case Token.SWITCH:
case Token.BREAK:
case Token.CATCH:
case Token.TRY:
case Token.SCRIPT:
case Token.EXPR_RESULT:
case Token.BLOCK:
case Token.EMPTY:
case Token.DEFAULT:
case Token.CONTINUE:
case Token.DEBUGGER:
case Token.THROW:
typeable = false;
break;
// These nodes require data flow analysis.
case Token.DO:
case Token.FOR:
case Token.IF:
case Token.WHILE:
typeable = false;
break;
// These nodes are typed during the type inference.
case Token.AND:
case Token.HOOK:
case Token.OBJECTLIT:
case Token.OR:
if (n.getJSType() != null) { // If we didn't run type inference.
ensureTyped(t, n);
} else {
// If this is an enum, then give that type to the objectlit as well.
if ((n.getType() == Token.OBJECTLIT)
&& (parent.getJSType() instanceof EnumType)) {
ensureTyped(t, n, parent.getJSType());
} else {
ensureTyped(t, n);
}
}
if (n.getType() == Token.OBJECTLIT) {
for (Node key : n.children()) {
visitObjLitKey(t, key, n);
}
}
break;
default:
report(t, n, UNEXPECTED_TOKEN, Token.name(n.getType()));
ensureTyped(t, n);
break;
}
// Don't count externs since the user's code may not even use that part.
typeable = typeable && !inExterns;
if (typeable) {
doPercentTypedAccounting(t, n);
}
checkNoTypeCheckSection(n, false);
}
/**
* Counts the given node in the typed statistics.
* @param n a node that should be typed
*/
private void doPercentTypedAccounting(NodeTraversal t, Node n) {
JSType type = n.getJSType();
if (type == null) {
nullCount++;
} else if (type.isUnknownType()) {
if (reportUnknownTypes.isOn()) {
compiler.report(
t.makeError(n, reportUnknownTypes, UNKNOWN_EXPR_TYPE));
}
unknownCount++;
} else {
typedCount++;
}
}
/**
* Visits an assignment <code>lvalue = rvalue</code>. If the
* <code>lvalue</code> is a prototype modification, we change the schema
* of the object type it is referring to.
* @param t the traversal
* @param assign the assign node
* (<code>assign.getType() == Token.ASSIGN</code> is an implicit invariant)
*/
private void visitAssign(NodeTraversal t, Node assign) {
JSDocInfo info = assign.getJSDocInfo();
Node lvalue = assign.getFirstChild();
Node rvalue = assign.getLastChild();
if (lvalue.getType() == Token.GETPROP) {
Node object = lvalue.getFirstChild();
JSType objectJsType = getJSType(object);
String property = lvalue.getLastChild().getString();
// the first name in this getprop refers to an interface
// we perform checks in addition to the ones below
if (object.getType() == Token.GETPROP) {
JSType jsType = getJSType(object.getFirstChild());
if (jsType.isInterface() &&
object.getLastChild().getString().equals("prototype")) {
visitInterfaceGetprop(t, assign, object, property, lvalue, rvalue);
}
}
// /** @type ... */object.name = ...;
if (info != null && info.hasType()) {
visitAnnotatedAssignGetprop(t, assign,
info.getType().evaluate(t.getScope(), typeRegistry), object,
property, rvalue);
return;
}
// /** @enum ... */object.name = ...;
if (info != null && info.hasEnumParameterType()) {
checkEnumInitializer(
t, rvalue, info.getEnumParameterType().evaluate(
t.getScope(), typeRegistry));
return;
}
// object.prototype = ...;
if (property.equals("prototype")) {
if (objectJsType != null && objectJsType.isFunctionType()) {
FunctionType functionType = objectJsType.toMaybeFunctionType();
if (functionType.isConstructor()) {
JSType rvalueType = rvalue.getJSType();
validator.expectObject(t, rvalue, rvalueType,
OVERRIDING_PROTOTYPE_WITH_NON_OBJECT);
}
} else {
// TODO(user): might want to flag that
}
return;
}
// object.prototype.property = ...;
if (object.getType() == Token.GETPROP) {
Node object2 = object.getFirstChild();
String property2 = NodeUtil.getStringValue(object.getLastChild());
if ("prototype".equals(property2)) {
JSType jsType = getJSType(object2);
if (jsType.isFunctionType()) {
FunctionType functionType = jsType.toMaybeFunctionType();
if (functionType.isConstructor() || functionType.isInterface()) {
checkDeclaredPropertyInheritance(
t, assign, functionType, property, info, getJSType(rvalue));
}
} else {
// TODO(user): might want to flag that
}
return;
}
}
// object.property = ...;
ObjectType type = ObjectType.cast(
objectJsType.restrictByNotNullOrUndefined());
if (type != null) {
if (type.hasProperty(property) &&
!type.isPropertyTypeInferred(property) &&
!propertyIsImplicitCast(type, property)) {
validator.expectCanAssignToPropertyOf(
t, assign, getJSType(rvalue),
type.getPropertyType(property), object, property);
}
return;
}
} else if (lvalue.getType() == Token.NAME) {
// variable with inferred type case
JSType rvalueType = getJSType(assign.getLastChild());
Var var = t.getScope().getVar(lvalue.getString());
if (var != null) {
if (var.isTypeInferred()) {
return;
}
}
}
// fall through case
JSType leftType = getJSType(lvalue);
Node rightChild = assign.getLastChild();
JSType rightType = getJSType(rightChild);
if (validator.expectCanAssignTo(
t, assign, rightType, leftType, "assignment")) {
ensureTyped(t, assign, rightType);
} else {
ensureTyped(t, assign);
}
}
/**
* Visits an object literal field definition <code>key : value</code>.
*
* If the <code>lvalue</code> is a prototype modification, we change the
* schema of the object type it is referring to.
*
* @param t the traversal
* @param key the assign node
*/
private void visitObjLitKey(NodeTraversal t, Node key, Node objlit) {
// TODO(johnlenz): Validate get and set function declarations are valid
// as is the functions can have "extraneous" bits.
// For getter and setter property definitions the
// rvalue type != the property type.
Node rvalue = key.getFirstChild();
JSType rightType = NodeUtil.getObjectLitKeyTypeFromValueType(
key, getJSType(rvalue));
if (rightType == null) {
rightType = getNativeType(UNKNOWN_TYPE);
}
Node owner = objlit;
// Validate value is assignable to the key type.
JSType keyType = getJSType(key);
boolean valid = validator.expectCanAssignToPropertyOf(t, key,
rightType, keyType,
owner, NodeUtil.getObjectLitKeyName(key));
if (valid) {
ensureTyped(t, key, rightType);
} else {
ensureTyped(t, key);
}
// Validate that the key type is assignable to the object property type.
// This is necessary as the objlit may have been cast to a non-literal
// object type.
// TODO(johnlenz): consider introducing a CAST node to the AST (or
// perhaps a parentheses node).
JSType objlitType = getJSType(objlit);
ObjectType type = ObjectType.cast(
objlitType.restrictByNotNullOrUndefined());
if (type != null) {
String property = NodeUtil.getObjectLitKeyName(key);
if (type.hasProperty(property) &&
!type.isPropertyTypeInferred(property) &&
!propertyIsImplicitCast(type, property)) {
validator.expectCanAssignToPropertyOf(
t, key, keyType,
type.getPropertyType(property), owner, property);
}
return;
}
}
/**
* Returns true if any type in the chain has an implictCast annotation for
* the given property.
*/
private boolean propertyIsImplicitCast(ObjectType type, String prop) {
for (; type != null; type = type.getImplicitPrototype()) {
JSDocInfo docInfo = type.getOwnPropertyJSDocInfo(prop);
if (docInfo != null && docInfo.isImplicitCast()) {
return true;
}
}
return false;
}
/**
* Given a constructor type and a property name, check that the property has
* the JSDoc annotation @override iff the property is declared on a
* superclass. Several checks regarding inheritance correctness are also
* performed.
*/
private void checkDeclaredPropertyInheritance(
NodeTraversal t, Node n, FunctionType ctorType, String propertyName,
JSDocInfo info, JSType propertyType) {
// If the supertype doesn't resolve correctly, we've warned about this
// already.
if (hasUnknownOrEmptySupertype(ctorType)) {
return;
}
FunctionType superClass = ctorType.getSuperClassConstructor();
boolean superClassHasProperty = superClass != null &&
superClass.getPrototype().hasProperty(propertyName);
// For interface
boolean superInterfacesHasProperty = false;
if (ctorType.isInterface()) {
for (ObjectType interfaceType : ctorType.getExtendedInterfaces()) {
superInterfacesHasProperty =
superInterfacesHasProperty || interfaceType.hasProperty(propertyName);
}
}
boolean declaredOverride = info != null && info.isOverride();
boolean foundInterfaceProperty = false;
if (ctorType.isConstructor()) {
for (JSType implementedInterface :
ctorType.getAllImplementedInterfaces()) {
if (implementedInterface.isUnknownType() ||
implementedInterface.isEmptyType()) {
continue;
}
FunctionType interfaceType =
implementedInterface.toObjectType().getConstructor();
Preconditions.checkNotNull(interfaceType);
boolean interfaceHasProperty =
interfaceType.getPrototype().hasProperty(propertyName);
foundInterfaceProperty = foundInterfaceProperty || interfaceHasProperty;
if (reportMissingOverride.isOn() && !declaredOverride &&
interfaceHasProperty) {
// @override not present, but the property does override an interface
// property
compiler.report(t.makeError(n, reportMissingOverride,
HIDDEN_INTERFACE_PROPERTY, propertyName,
interfaceType.getTopMostDefiningType(propertyName).toString()));
}
}
}
if (!declaredOverride && !superClassHasProperty
&& !superInterfacesHasProperty) {
// nothing to do here, it's just a plain new property
return;
}
JSType topInstanceType = superClassHasProperty ?
superClass.getTopMostDefiningType(propertyName) : null;
if (reportMissingOverride.isOn() && ctorType.isConstructor() &&
!declaredOverride && superClassHasProperty) {
// @override not present, but the property does override a superclass
// property
compiler.report(t.makeError(n, reportMissingOverride,
HIDDEN_SUPERCLASS_PROPERTY, propertyName,
topInstanceType.toString()));
}
if (!declaredOverride) {
// there's no @override to check
return;
}
// @override is present and we have to check that it is ok
if (superClassHasProperty) {
// there is a superclass implementation
JSType superClassPropType =
superClass.getPrototype().getPropertyType(propertyName);
if (!propertyType.canAssignTo(superClassPropType)) {
compiler.report(
t.makeError(n, HIDDEN_SUPERCLASS_PROPERTY_MISMATCH,
propertyName, topInstanceType.toString(),
superClassPropType.toString(), propertyType.toString()));
}
} else if (superInterfacesHasProperty) {
// there is an super interface property
for (ObjectType interfaceType : ctorType.getExtendedInterfaces()) {
if (interfaceType.hasProperty(propertyName)) {
JSType superPropertyType =
interfaceType.getPropertyType(propertyName);
if (!propertyType.canAssignTo(superPropertyType)) {
topInstanceType = interfaceType.getConstructor().
getTopMostDefiningType(propertyName);
compiler.report(
t.makeError(n, HIDDEN_SUPERCLASS_PROPERTY_MISMATCH,
propertyName, topInstanceType.toString(),
superPropertyType.toString(),
propertyType.toString()));
}
}
}
} else if (!foundInterfaceProperty) {
// there is no superclass nor interface implementation
compiler.report(
t.makeError(n, UNKNOWN_OVERRIDE,
propertyName, ctorType.getInstanceType().toString()));
}
}
/**
* Given a constructor or an interface type, find out whether the unknown
* type is a supertype of the current type.
*/
private static boolean hasUnknownOrEmptySupertype(FunctionType ctor) {
Preconditions.checkArgument(ctor.isConstructor() || ctor.isInterface());
Preconditions.checkArgument(!ctor.isUnknownType());
// The type system should notice inheritance cycles on its own
// and break the cycle.
while (true) {
ObjectType maybeSuperInstanceType =
ctor.getPrototype().getImplicitPrototype();
if (maybeSuperInstanceType == null) {
return false;
}
if (maybeSuperInstanceType.isUnknownType() ||
maybeSuperInstanceType.isEmptyType()) {
return true;
}
ctor = maybeSuperInstanceType.getConstructor();
if (ctor == null) {
return false;
}
Preconditions.checkState(ctor.isConstructor() || ctor.isInterface());
}
}
/**
* Visits an ASSIGN node for cases such as
* <pre>
* interface.property2.property = ...;
* </pre>
*/
private void visitInterfaceGetprop(NodeTraversal t, Node assign, Node object,
String property, Node lvalue, Node rvalue) {
JSType rvalueType = getJSType(rvalue);
// Only 2 values are allowed for methods:
// goog.abstractMethod
// function () {};
// or for properties, no assignment such as:
// InterfaceFoo.prototype.foobar;
String abstractMethodName =
compiler.getCodingConvention().getAbstractMethodName();
if (!rvalueType.isOrdinaryFunction() &&
!(rvalue.isQualifiedName() &&
rvalue.getQualifiedName().equals(abstractMethodName))) {
// This is bad i18n style but we don't localize our compiler errors.
String abstractMethodMessage = (abstractMethodName != null)
? ", or " + abstractMethodName
: "";
compiler.report(
t.makeError(object, INVALID_INTERFACE_MEMBER_DECLARATION,
abstractMethodMessage));
}
if (assign.getLastChild().getType() == Token.FUNCTION
&& !NodeUtil.isEmptyBlock(assign.getLastChild().getLastChild())) {
compiler.report(
t.makeError(object, INTERFACE_FUNCTION_NOT_EMPTY,
abstractMethodName));
}
}
/**
* Visits an ASSIGN node for cases such as
* <pre>
* object.property = ...;
* </pre>
* that have an {@code @type} annotation.
*/
private void visitAnnotatedAssignGetprop(NodeTraversal t,
Node assign, JSType type, Node object, String property, Node rvalue) {
// verifying that the rvalue has the correct type
validator.expectCanAssignToPropertyOf(t, assign, getJSType(rvalue), type,
object, property);
}
/**
* Visits a NAME node.
*
* @param t The node traversal object that supplies context, such as the
* scope chain to use in name lookups as well as error reporting.
* @param n The node being visited.
* @param parent The parent of the node n.
* @return whether the node is typeable or not
*/
boolean visitName(NodeTraversal t, Node n, Node parent) {
// At this stage, we need to determine whether this is a leaf
// node in an expression (which therefore needs to have a type
// assigned for it) versus some other decorative node that we
// can safely ignore. Function names, arguments (children of LP nodes) and
// variable declarations are ignored.
// TODO(user): remove this short-circuiting in favor of a
// pre order traversal of the FUNCTION, CATCH, LP and VAR nodes.
int parentNodeType = parent.getType();
if (parentNodeType == Token.FUNCTION ||
parentNodeType == Token.CATCH ||
parentNodeType == Token.LP ||
parentNodeType == Token.VAR) {
return false;
}
JSType type = n.getJSType();
if (type == null) {
type = getNativeType(UNKNOWN_TYPE);
Var var = t.getScope().getVar(n.getString());
if (var != null) {
JSType varType = var.getType();
if (varType != null) {
type = varType;
}
}
}
ensureTyped(t, n, type);
return true;
}
/**
* Visits a GETPROP node.
*
* @param t The node traversal object that supplies context, such as the
* scope chain to use in name lookups as well as error reporting.
* @param n The node being visited.
* @param parent The parent of <code>n</code>
*/
private void visitGetProp(NodeTraversal t, Node n, Node parent) {
// GETPROP nodes have an assigned type on their node by the scope creator
// if this is an enum declaration. The only namespaced enum declarations
// that we allow are of the form object.name = ...;
if (n.getJSType() != null && parent.getType() == Token.ASSIGN) {
return;
}
// obj.prop or obj.method()
// Lots of types can appear on the left, a call to a void function can
// never be on the left. getPropertyType will decide what is acceptable
// and what isn't.
Node property = n.getLastChild();
Node objNode = n.getFirstChild();
JSType childType = getJSType(objNode);
// TODO(user): remove in favor of flagging every property access on
// non-object.
if (!validator.expectNotNullOrUndefined(t, n, childType,
childType + " has no properties", getNativeType(OBJECT_TYPE))) {
ensureTyped(t, n);
return;
}
checkPropertyAccess(childType, property.getString(), t, n);
ensureTyped(t, n);
}
/**
* Emit a warning if we can prove that a property cannot possibly be
* defined on an object. Note the difference between JS and a strictly
* statically typed language: we're checking if the property
* *cannot be defined*, whereas a java compiler would check if the
* property *can be undefined*.
*/
private void checkPropertyAccess(JSType childType, String propName,
NodeTraversal t, Node n) {
// If the property type is unknown, check the object type to see if it
// can ever be defined. We explicitly exclude CHECKED_UNKNOWN (for
// properties where we've checked that it exists, or for properties on
// objects that aren't in this binary).
JSType propType = getJSType(n);
if (propType.equals(typeRegistry.getNativeType(UNKNOWN_TYPE))) {
childType = childType.autobox();
ObjectType objectType = ObjectType.cast(childType);
if (objectType != null) {
// We special-case object types so that checks on enums can be
// much stricter, and so that we can use hasProperty (which is much
// faster in most cases).
if (!objectType.hasProperty(propName) ||
objectType.equals(typeRegistry.getNativeType(UNKNOWN_TYPE))) {
if (objectType instanceof EnumType) {
report(t, n, INEXISTENT_ENUM_ELEMENT, propName);
} else {
checkPropertyAccessHelper(objectType, propName, t, n);
}
}
} else {
checkPropertyAccessHelper(childType, propName, t, n);
}
}
}
private void checkPropertyAccessHelper(JSType objectType, String propName,
NodeTraversal t, Node n) {
if (!objectType.isEmptyType() &&
reportMissingProperties && !isPropertyTest(n)) {
if (!typeRegistry.canPropertyBeDefined(objectType, propName)) {
report(t, n, INEXISTENT_PROPERTY, propName,
validator.getReadableJSTypeName(n.getFirstChild(), true));
}
}
}
/**
* Determines whether this node is testing for the existence of a property.
* If true, we will not emit warnings about a missing property.
*
* @param getProp The GETPROP being tested.
*/
private boolean isPropertyTest(Node getProp) {
Node parent = getProp.getParent();
switch (parent.getType()) {
case Token.CALL:
return parent.getFirstChild() != getProp &&
compiler.getCodingConvention().isPropertyTestFunction(parent);
case Token.IF:
case Token.WHILE:
case Token.DO:
case Token.FOR:
return NodeUtil.getConditionExpression(parent) == getProp;
case Token.INSTANCEOF:
case Token.TYPEOF:
return true;
case Token.AND:
case Token.HOOK:
return parent.getFirstChild() == getProp;
case Token.NOT:
return parent.getParent().getType() == Token.OR &&
parent.getParent().getFirstChild() == parent;
}
return false;
}
/**
* Visits a GETELEM node.
*
* @param t The node traversal object that supplies context, such as the
* scope chain to use in name lookups as well as error reporting.
* @param n The node being visited.
*/
private void visitGetElem(NodeTraversal t, Node n) {
Node left = n.getFirstChild();
Node right = n.getLastChild();
validator.expectIndexMatch(t, n, getJSType(left), getJSType(right));
ensureTyped(t, n);
}
/**
* Visits a VAR node.
*
* @param t The node traversal object that supplies context, such as the
* scope chain to use in name lookups as well as error reporting.
* @param n The node being visited.
*/
private void visitVar(NodeTraversal t, Node n) {
// TODO(nicksantos): Fix this so that the doc info always shows up
// on the NAME node. We probably want to wait for the parser
// merge to fix this.
JSDocInfo varInfo = n.hasOneChild() ? n.getJSDocInfo() : null;
for (Node name : n.children()) {
Node value = name.getFirstChild();
// A null var would indicate a bug in the scope creation logic.
Var var = t.getScope().getVar(name.getString());
if (value != null) {
JSType valueType = getJSType(value);
JSType nameType = var.getType();
nameType = (nameType == null) ? getNativeType(UNKNOWN_TYPE) : nameType;
JSDocInfo info = name.getJSDocInfo();
if (info == null) {
info = varInfo;
}
if (info != null && info.hasEnumParameterType()) {
// var.getType() can never be null, this would indicate a bug in the
// scope creation logic.
checkEnumInitializer(
t, value,
info.getEnumParameterType().evaluate(t.getScope(), typeRegistry));
} else if (var.isTypeInferred()) {
ensureTyped(t, name, valueType);
} else {
validator.expectCanAssignTo(
t, value, valueType, nameType, "initializing variable");
}
}
}
}
/**
* Visits a NEW node.
*/
private void visitNew(NodeTraversal t, Node n) {
Node constructor = n.getFirstChild();
JSType type = getJSType(constructor).restrictByNotNullOrUndefined();
if (type.isConstructor() || type.isEmptyType() || type.isUnknownType()) {
FunctionType fnType = type.toMaybeFunctionType();
if (fnType != null) {
visitParameterList(t, n, fnType);
ensureTyped(t, n, fnType.getInstanceType());
} else {
ensureTyped(t, n);
}
} else {
report(t, n, NOT_A_CONSTRUCTOR);
ensureTyped(t, n);
}
}
/**
* Check whether there's any property conflict for for a particular super
* interface
* @param t The node traversal object that supplies context
* @param n The node being visited
* @param functionName The function name being checked
* @param properties The property names in the super interfaces that have
* been visited
* @param currentProperties The property names in the super interface
* that have been visited
* @param interfaceType The super interface that is being visited
*/
private void checkInterfaceConflictProperties(NodeTraversal t, Node n,
String functionName, HashMap<String, ObjectType> properties,
HashMap<String, ObjectType> currentProperties,
ObjectType interfaceType) {
Set<String> currentPropertyNames = interfaceType.getPropertyNames();
for (String name : currentPropertyNames) {
ObjectType oType = properties.get(name);
if (oType != null) {
if (!interfaceType.getPropertyType(name).isEquivalentTo(
oType.getPropertyType(name))) {
compiler.report(
t.makeError(n, INCOMPATIBLE_EXTENDED_PROPERTY_TYPE,
functionName, name, oType.toString(),
interfaceType.toString()));
}
}
currentProperties.put(name, interfaceType);
}
for (ObjectType iType : interfaceType.getCtorExtendedInterfaces()) {
checkInterfaceConflictProperties(t, n, functionName, properties,
currentProperties, iType);
}
}
/**
* Visits a {@link Token#FUNCTION} node.
*
* @param t The node traversal object that supplies context, such as the
* scope chain to use in name lookups as well as error reporting.
* @param n The node being visited.
*/
private void visitFunction(NodeTraversal t, Node n) {
FunctionType functionType = JSType.toMaybeFunctionType(n.getJSType());
String functionPrivateName = n.getFirstChild().getString();
if (functionType.isConstructor()) {
FunctionType baseConstructor = functionType.getSuperClassConstructor();
if (baseConstructor != null &&
baseConstructor != getNativeType(OBJECT_FUNCTION_TYPE) &&
(baseConstructor.isInterface() && functionType.isConstructor())) {
compiler.report(
t.makeError(n, CONFLICTING_EXTENDED_TYPE, functionPrivateName));
} else {
// All interfaces are properly implemented by a class
for (JSType baseInterface : functionType.getImplementedInterfaces()) {
boolean badImplementedType = false;
ObjectType baseInterfaceObj = ObjectType.cast(baseInterface);
if (baseInterfaceObj != null) {
FunctionType interfaceConstructor =
baseInterfaceObj.getConstructor();
if (interfaceConstructor != null &&
!interfaceConstructor.isInterface()) {
badImplementedType = true;
}
} else {
badImplementedType = true;
}
if (badImplementedType) {
report(t, n, BAD_IMPLEMENTED_TYPE, functionPrivateName);
}
}
// check properties
validator.expectAllInterfaceProperties(t, n, functionType);
}
} else if (functionType.isInterface()) {
// Interface must extend only interfaces
for (ObjectType extInterface : functionType.getExtendedInterfaces()) {
if (extInterface.getConstructor() != null
&& !extInterface.getConstructor().isInterface()) {
compiler.report(
t.makeError(n, CONFLICTING_EXTENDED_TYPE, functionPrivateName));
}
}
// Interface cannot implement any interfaces
if (functionType.hasImplementedInterfaces()) {
compiler.report(t.makeError(n,
CONFLICTING_IMPLEMENTED_TYPE, functionPrivateName));
}
// Check whether the extended interfaces have any conflicts
if (functionType.getExtendedInterfacesCount() > 1) {
// Only check when extending more than one interfaces
HashMap<String, ObjectType> properties
= new HashMap<String, ObjectType>();
HashMap<String, ObjectType> currentProperties
= new HashMap<String, ObjectType>();
for (ObjectType interfaceType : functionType.getExtendedInterfaces()) {
currentProperties.clear();
checkInterfaceConflictProperties(t, n, functionPrivateName,
properties, currentProperties, interfaceType);
properties.putAll(currentProperties);
}
}
}
}
/**
* Visits a CALL node.
*
* @param t The node traversal object that supplies context, such as the
* scope chain to use in name lookups as well as error reporting.
* @param n The node being visited.
*/
private void visitCall(NodeTraversal t, Node n) {
Node child = n.getFirstChild();
JSType childType = getJSType(child).restrictByNotNullOrUndefined();
if (!childType.canBeCalled()) {
report(t, n, NOT_CALLABLE, childType.toString());
ensureTyped(t, n);
return;
}
// A couple of types can be called as if they were functions.
// If it is a function type, then validate parameters.
if (childType.isFunctionType()) {
FunctionType functionType = childType.toMaybeFunctionType();
boolean isExtern = false;
JSDocInfo functionJSDocInfo = functionType.getJSDocInfo();
if(functionJSDocInfo != null) {
isExtern = functionJSDocInfo.getAssociatedNode().isFromExterns();
}
// Non-native constructors should not be called directly
// unless they specify a return type and are defined
// in an extern.
if (functionType.isConstructor() &&
!functionType.isNativeObjectType() &&
(functionType.getReturnType().isUnknownType() ||
functionType.getReturnType().isVoidType() ||
!isExtern)) {
report(t, n, CONSTRUCTOR_NOT_CALLABLE, childType.toString());
}
// Functions with explcit 'this' types must be called in a GETPROP
// or GETELEM.
if (functionType.isOrdinaryFunction() &&
!functionType.getTypeOfThis().isUnknownType() &&
!functionType.getTypeOfThis().isNativeObjectType() &&
!(child.getType() == Token.GETELEM ||
child.getType() == Token.GETPROP)) {
report(t, n, EXPECTED_THIS_TYPE, functionType.toString());
}
visitParameterList(t, n, functionType);
ensureTyped(t, n, functionType.getReturnType());
} else {
ensureTyped(t, n);
}
// TODO: Add something to check for calls of RegExp objects, which is not
// supported by IE. Either say something about the return type or warn
// about the non-portability of the call or both.
}
/**
* Visits the parameters of a CALL or a NEW node.
*/
private void visitParameterList(NodeTraversal t, Node call,
FunctionType functionType) {
Iterator<Node> arguments = call.children().iterator();
arguments.next(); // skip the function name
Iterator<Node> parameters = functionType.getParameters().iterator();
int ordinal = 0;
Node parameter = null;
Node argument = null;
while (arguments.hasNext() &&
(parameters.hasNext() ||
parameter != null && parameter.isVarArgs())) {
// If there are no parameters left in the list, then the while loop
// above implies that this must be a var_args function.
if (parameters.hasNext()) {
parameter = parameters.next();
}
argument = arguments.next();
ordinal++;
validator.expectArgumentMatchesParameter(t, argument,
getJSType(argument), getJSType(parameter), call, ordinal);
}
int numArgs = call.getChildCount() - 1;
int minArgs = functionType.getMinArguments();
int maxArgs = functionType.getMaxArguments();
if (minArgs > numArgs || maxArgs < numArgs) {
report(t, call, WRONG_ARGUMENT_COUNT,
validator.getReadableJSTypeName(call.getFirstChild(), false),
String.valueOf(numArgs), String.valueOf(minArgs),
maxArgs != Integer.MAX_VALUE ?
" and no more than " + maxArgs + " argument(s)" : "");
}
}
/**
* Visits a RETURN node.
*
* @param t The node traversal object that supplies context, such as the
* scope chain to use in name lookups as well as error reporting.
* @param n The node being visited.
*/
private void visitReturn(NodeTraversal t, Node n) {
Node function = t.getEnclosingFunction();
// This is a misplaced return, but the real JS will fail to compile,
// so let it go.
if (function == null) {
return;
}
JSType jsType = getJSType(function);
if (jsType.isFunctionType()) {
FunctionType functionType = jsType.toMaybeFunctionType();
JSType returnType = functionType.getReturnType();
// if no return type is specified, undefined must be returned
// (it's a void function)
if (returnType == null) {
returnType = getNativeType(VOID_TYPE);
}
// fetching the returned value's type
Node valueNode = n.getFirstChild();
JSType actualReturnType;
if (valueNode == null) {
actualReturnType = getNativeType(VOID_TYPE);
valueNode = n;
} else {
actualReturnType = getJSType(valueNode);
}
// verifying
validator.expectCanAssignTo(t, valueNode, actualReturnType, returnType,
"inconsistent return type");
}
}
/**
* This function unifies the type checking involved in the core binary
* operators and the corresponding assignment operators. The representation
* used internally is such that common code can handle both kinds of
* operators easily.
*
* @param op The operator.
* @param t The traversal object, needed to report errors.
* @param n The node being checked.
*/
private void visitBinaryOperator(int op, NodeTraversal t, Node n) {
Node left = n.getFirstChild();
JSType leftType = getJSType(left);
Node right = n.getLastChild();
JSType rightType = getJSType(right);
switch (op) {
case Token.ASSIGN_LSH:
case Token.ASSIGN_RSH:
case Token.LSH:
case Token.RSH:
case Token.ASSIGN_URSH:
case Token.URSH:
if (!leftType.matchesInt32Context()) {
report(t, left, BIT_OPERATION,
NodeUtil.opToStr(n.getType()), leftType.toString());
}
if (!rightType.matchesUint32Context()) {
report(t, right, BIT_OPERATION,
NodeUtil.opToStr(n.getType()), rightType.toString());
}
break;
case Token.ASSIGN_DIV:
case Token.ASSIGN_MOD:
case Token.ASSIGN_MUL:
case Token.ASSIGN_SUB:
case Token.DIV:
case Token.MOD:
case Token.MUL:
case Token.SUB:
validator.expectNumber(t, left, leftType, "left operand");
validator.expectNumber(t, right, rightType, "right operand");
break;
case Token.ASSIGN_BITAND:
case Token.ASSIGN_BITXOR:
case Token.ASSIGN_BITOR:
case Token.BITAND:
case Token.BITXOR:
case Token.BITOR:
validator.expectBitwiseable(t, left, leftType,
"bad left operand to bitwise operator");
validator.expectBitwiseable(t, right, rightType,
"bad right operand to bitwise operator");
break;
case Token.ASSIGN_ADD:
case Token.ADD:
break;
default:
report(t, n, UNEXPECTED_TOKEN, Node.tokenToName(op));
}
ensureTyped(t, n);
}
/**
* <p>Checks the initializer of an enum. An enum can be initialized with an
* object literal whose values must be subtypes of the declared enum element
* type, or by copying another enum.</p>
*
* <p>In the case of an enum copy, we verify that the enum element type of the
* enum used for initialization is a subtype of the enum element type of
* the enum the value is being copied in.</p>
*
* <p>Examples:</p>
* <pre>var myEnum = {FOO: ..., BAR: ...};
* var myEnum = myOtherEnum;</pre>
*
* @param value the value used for initialization of the enum
* @param primitiveType The type of each element of the enum.
*/
private void checkEnumInitializer(
NodeTraversal t, Node value, JSType primitiveType) {
if (value.getType() == Token.OBJECTLIT) {
for (Node key = value.getFirstChild();
key != null; key = key.getNext()) {
Node propValue = key.getFirstChild();
// the value's type must be assignable to the enum's primitive type
validator.expectCanAssignTo(
t, propValue, getJSType(propValue), primitiveType,
"element type must match enum's type");
}
} else if (value.getJSType() instanceof EnumType) {
// TODO(user): Remove the instanceof check in favor
// of a type.isEnumType() predicate. Currently, not all enum types are
// implemented by the EnumClass, e.g. the unknown type and the any
// type. The types need to be defined by interfaces such that an
// implementation can implement multiple types interface.
EnumType valueEnumType = (EnumType) value.getJSType();
JSType valueEnumPrimitiveType =
valueEnumType.getElementsType().getPrimitiveType();
validator.expectCanAssignTo(t, value, valueEnumPrimitiveType,
primitiveType, "incompatible enum element types");
} else {
// The error condition is handled in TypedScopeCreator.
}
}
/**
* This method gets the JSType from the Node argument and verifies that it is
* present.
*/
private JSType getJSType(Node n) {
JSType jsType = n.getJSType();
if (jsType == null) {
// TODO(nicksantos): This branch indicates a compiler bug, not worthy of
// halting the compilation but we should log this and analyze to track
// down why it happens. This is not critical and will be resolved over
// time as the type checker is extended.
return getNativeType(UNKNOWN_TYPE);
} else {
return jsType;
}
}
// TODO(nicksantos): TypeCheck should never be attaching types to nodes.
// All types should be attached by TypeInference. This is not true today
// for legacy reasons. There are a number of places where TypeInference
// doesn't attach a type, as a signal to TypeCheck that it needs to check
// that node's type.
/**
* Ensure that the given node has a type. If it does not have one,
* attach the UNKNOWN_TYPE.
*/
private void ensureTyped(NodeTraversal t, Node n) {
ensureTyped(t, n, getNativeType(UNKNOWN_TYPE));
}
private void ensureTyped(NodeTraversal t, Node n, JSTypeNative type) {
ensureTyped(t, n, getNativeType(type));
}
/**
* Enforces type casts, and ensures the node is typed.
*
* A cast in the way that we use it in JSDoc annotations never
* alters the generated code and therefore never can induce any runtime
* operation. What this means is that a 'cast' is really just a compile
* time constraint on the underlying value. In the future, we may add
* support for run-time casts for compiled tests.
*
* To ensure some shred of sanity, we enforce the notion that the
* type you are casting to may only meaningfully be a narrower type
* than the underlying declared type. We also invalidate optimizations
* on bad type casts.
*
* @param t The traversal object needed to report errors.
* @param n The node getting a type assigned to it.
* @param type The type to be assigned.
*/
private void ensureTyped(NodeTraversal t, Node n, JSType type) {
// Make sure FUNCTION nodes always get function type.
Preconditions.checkState(n.getType() != Token.FUNCTION ||
type.isFunctionType() ||
type.isUnknownType());
JSDocInfo info = n.getJSDocInfo();
if (info != null) {
if (info.hasType()) {
JSType infoType = info.getType().evaluate(t.getScope(), typeRegistry);
validator.expectCanCast(t, n, infoType, type);
type = infoType;
}
if (info.isImplicitCast() && !inExterns) {
String propName = n.getType() == Token.GETPROP ?
n.getLastChild().getString() : "(missing)";
compiler.report(
t.makeError(n, ILLEGAL_IMPLICIT_CAST, propName));
}
}
if (n.getJSType() == null) {
n.setJSType(type);
}
}
/**
* Returns the percentage of nodes typed by the type checker.
* @return a number between 0.0 and 100.0
*/
double getTypedPercent() {
int total = nullCount + unknownCount + typedCount;
if (total == 0) {
return 0.0;
} else {
return (100.0 * typedCount) / total;
}
}
private JSType getNativeType(JSTypeNative typeId) {
return typeRegistry.getNativeType(typeId);
}
}