com.google.javascript.jscomp.modules.Binding Maven / Gradle / Ivy
/*
* Copyright 2018 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.modules;
import static com.google.common.base.Preconditions.checkNotNull;
import static com.google.common.base.Preconditions.checkState;
import com.google.auto.value.AutoValue;
import com.google.javascript.jscomp.modules.ModuleMetadataMap.ModuleMetadata;
import com.google.javascript.rhino.Node;
import javax.annotation.Nullable;
/**
* Represents a variable bound by an import or export statement. This can either be a single
* variable or a entire module namespace created by an import * statement.
*
* See {@link Module#namespace()} and {@link Module#boundNames()} for how Bindings are used.
*/
@AutoValue
public abstract class Binding {
// Prevent unwanted subclasses.
Binding() {}
/** Binding for an exported value that is not a module namespace object. */
static Binding from(Export boundExport, Node sourceNode) {
return new AutoValue_Binding(
boundExport.moduleMetadata(),
sourceNode,
boundExport,
/* isModuleNamespace= */ false,
/* closureNamespace= */ null);
}
/** Binding for an entire module namespace created by an import *. */
static Binding from(Module namespaceBoundModule, Node sourceNode) {
return new AutoValue_Binding(
namespaceBoundModule.metadata(),
sourceNode,
/* originatingExport= */ null,
/* isModuleNamespace= */ true,
namespaceBoundModule.closureNamespace());
}
/** Copies the binding with a new source node. */
Binding withSource(Node sourceNode) {
checkNotNull(sourceNode);
return new AutoValue_Binding(
metadata(), sourceNode, originatingExport(), isModuleNamespace(), closureNamespace());
}
/**
* Metadata of the module this is bound to.
*
*
If this was made from an {@code import *} then it is the module that this imported.
* Otherwise it is the module this binding was created in (e.g. the module of the originating
* export).
*/
public abstract ModuleMetadata metadata();
/**
* The AST node to use for source location when rewriting.
*
*
This is generally a NAME node inside an import or export statement that represents where the
* name was bound. However as {@code export * from} has no NAME nodes the source node in that
* instance should be the entire export node.
*/
public abstract Node sourceNode();
/**
* Returns the original export if this binding was created by an export.
*
*
For transitive exports this will still be the *original* export, not the transitive link.
*/
@Nullable
public abstract Export originatingExport();
/** True if this represents a module namespace, e.g. created by {@code import *} */
public abstract boolean isModuleNamespace();
@Nullable
public abstract String closureNamespace();
/**
* The name of the variable this export is bound to, assuming it is not a binding of a module
* namespace.
*/
public final String boundName() {
checkState(!isModuleNamespace());
return originatingExport().localName();
}
/**
* Returns whether or not this export is potentially mutated after module execution (i.e. in a
* function scope).
*/
public final boolean isMutated() {
// Module namespaces can never be mutated. They are always imported, and import bound names
// are const.
return !isModuleNamespace() && originatingExport().mutated();
}
}