// Copyright 2016 The Bazel Authors. All rights reserved.
//
// 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.devtools.build.lib.packages;
import com.google.common.annotations.VisibleForTesting;
import com.google.common.base.Joiner;
import com.google.common.base.Objects;
import com.google.common.base.Preconditions;
import com.google.common.collect.ImmutableCollection;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.Ordering;
import com.google.devtools.build.lib.events.Location;
import com.google.devtools.build.lib.skyframe.serialization.autocodec.AutoCodec.VisibleForSerialization;
import com.google.devtools.build.lib.skylarkbuildapi.StructApi;
import com.google.devtools.build.lib.skylarkinterface.SkylarkPrinter;
import com.google.devtools.build.lib.syntax.ClassObject;
import com.google.devtools.build.lib.syntax.Environment;
import com.google.devtools.build.lib.syntax.EvalException;
import com.google.devtools.build.lib.syntax.EvalUtils;
import com.google.devtools.build.lib.syntax.Printer;
import com.google.devtools.build.lib.syntax.Runtime;
import com.google.devtools.build.lib.syntax.SkylarkList;
import com.google.devtools.build.lib.syntax.SkylarkType;
import com.google.protobuf.TextFormat;
import java.io.Serializable;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import javax.annotation.Nullable;
/** An instance (in the Skylark sense, not Java) of a {@link Provider}. */
public abstract class Info implements ClassObject, StructApi, Serializable {
/** The {@link Provider} that describes the type of this instance. */
private final Provider provider;
/**
* The Skylark location where this provider instance was created.
*
*
Built-in provider instances may use {@link Location#BUILTIN}.
*/
@VisibleForSerialization protected final Location location;
/**
* Constructs an {@link Info}.
*
* @param provider the provider describing the type of this instance
* @param location the Skylark location where this instance is created. If null, defaults to
* {@link Location#BUILTIN}.
*/
protected Info(Provider provider, @Nullable Location location) {
this.provider = Preconditions.checkNotNull(provider);
this.location = location == null ? Location.BUILTIN : location;
}
/**
* Preprocesses a map of field values to convert the field names and field values to
* Skylark-acceptable names and types.
*
*
This preserves the order of the map entries.
*/
protected static ImmutableMap copyValues(Map values) {
Preconditions.checkNotNull(values);
ImmutableMap.Builder builder = ImmutableMap.builder();
for (Map.Entry e : values.entrySet()) {
builder.put(
Attribute.getSkylarkName(e.getKey()),
SkylarkType.convertToSkylark(e.getValue(), (Environment) null));
}
return builder.build();
}
/**
* Returns the Skylark location where this provider instance was created.
*
*
Builtin provider instances may return {@link Location#BUILTIN}.
*/
public Location getCreationLoc() {
return location;
}
public Provider getProvider() {
return provider;
}
/**
* Returns whether the given field name exists.
*
*
This conceptually extends the API for {@link ClassObject}.
*/
public abstract boolean hasField(String name);
/**
*
Wraps {@link ClassObject#getValue(String)}, returning null in cases where
* {@link EvalException} would have been thrown.
*/
@VisibleForTesting
public Object getValueOrNull(String name) {
try {
return getValue(name);
} catch (EvalException e) {
return null;
}
}
/**
* Returns the result of {@link #getValue(String)}, cast as the given type, throwing {@link
* EvalException} if the cast fails.
*/
public T getValue(String key, Class type) throws EvalException {
Object obj = getValue(key);
if (obj == null) {
return null;
}
SkylarkType.checkType(obj, type, key);
return type.cast(obj);
}
/**
* {@inheritDoc}
*
*
Overrides {@link ClassObject#getFieldNames()}, but does not allow {@link EvalException} to
* be thrown.
*/
@Override
public abstract ImmutableCollection getFieldNames();
/**
* Returns the error message format to use for unknown fields.
*
*
By default, it is the one specified by the provider.
*/
protected String getErrorMessageFormatForUnknownField() {
return provider.getErrorMessageFormatForUnknownField();
}
@Override
public String getErrorMessageForUnknownField(String name) {
String suffix = "Available attributes: "
+ Joiner.on(", ").join(Ordering.natural().sortedCopy(getFieldNames()));
return String.format(getErrorMessageFormatForUnknownField(), name) + "\n" + suffix;
}
@Override
public boolean equals(Object otherObject) {
if (!(otherObject instanceof Info)) {
return false;
}
Info other = (Info) otherObject;
if (this == other) {
return true;
}
if (!this.provider.equals(other.provider)) {
return false;
}
// Compare objects' fields and their values
if (!this.getFieldNames().equals(other.getFieldNames())) {
return false;
}
for (String field : getFieldNames()) {
if (!Objects.equal(this.getValueOrNull(field), other.getValueOrNull(field))) {
return false;
}
}
return true;
}
@Override
public int hashCode() {
List fields = new ArrayList<>(getFieldNames());
Collections.sort(fields);
List