| // 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.base.Preconditions; |
| import com.google.common.collect.ImmutableList; |
| import com.google.common.collect.ImmutableMap; |
| import com.google.devtools.build.lib.cmdline.Label; |
| import com.google.devtools.build.lib.events.Location; |
| import com.google.devtools.build.lib.skylarkinterface.SkylarkPrinter; |
| import com.google.devtools.build.lib.syntax.EvalException; |
| import com.google.devtools.build.lib.syntax.FunctionSignature; |
| import com.google.devtools.build.lib.syntax.SkylarkType; |
| import java.util.Map; |
| import java.util.Objects; |
| import javax.annotation.Nullable; |
| |
| /** |
| * Declared provider defined in Skylark. |
| * |
| * <p>This is a result of calling {@code provider()} function from Skylark ({@link |
| * com.google.devtools.build.lib.analysis.skylark.SkylarkRuleClassFunctions#provider}). |
| */ |
| public class SkylarkProvider extends Provider implements SkylarkExportable { |
| |
| private static final FunctionSignature.WithValues<Object, SkylarkType> SIGNATURE = |
| FunctionSignature.WithValues.create(FunctionSignature.KWARGS); |
| |
| @Nullable private SkylarkKey key; |
| @Nullable private String errorMessageFormatForInstances; |
| |
| private static final String DEFAULT_ERROR_MESSAFE = "Object has no '%s' attribute."; |
| |
| /** |
| * Creates a Skylark-defined Declared Provider ({@link Info} constructor). |
| * |
| * <p>Needs to be exported later. |
| */ |
| public SkylarkProvider(String name, |
| @Nullable Iterable<String> fields, |
| Location location) { |
| this(name, buildSignature(fields), location); |
| } |
| |
| private SkylarkProvider( |
| String name, |
| FunctionSignature.WithValues<Object, SkylarkType> signature, Location location) { |
| super(name, signature, location); |
| this.errorMessageFormatForInstances = DEFAULT_ERROR_MESSAFE; |
| } |
| |
| private static FunctionSignature.WithValues<Object, SkylarkType> buildSignature( |
| @Nullable Iterable<String> fields) { |
| if (fields == null) { |
| return SIGNATURE; |
| } |
| return |
| FunctionSignature.WithValues.create( |
| FunctionSignature.namedOnly(0, ImmutableList.copyOf(fields).toArray(new String[0])) |
| ); |
| } |
| |
| @Override |
| protected Info createInstanceFromSkylark(Object[] args, Location loc) throws EvalException { |
| if (signature.getSignature().getShape().hasKwArg()) { |
| @SuppressWarnings("unchecked") |
| Map<String, Object> kwargs = (Map<String, Object>) args[0]; |
| return new SkylarkInfo(this, kwargs, loc); |
| } else { |
| // todo(dslomov): implement shape sharing. |
| ImmutableList<String> names = signature.getSignature().getNames(); |
| Preconditions.checkState(names.size() == args.length); |
| ImmutableMap.Builder<String, Object> fields = ImmutableMap.builder(); |
| for (int i = 0; i < args.length; i++) { |
| if (args[i] != null) { |
| fields.put(names.get(i), args[i]); |
| } |
| } |
| return new SkylarkInfo(this, fields.build(), loc); |
| } |
| } |
| |
| @Override |
| public boolean isExported() { |
| return key != null; |
| } |
| |
| @Override |
| public SkylarkKey getKey() { |
| Preconditions.checkState(isExported()); |
| return key; |
| } |
| |
| @Override |
| public String getName() { |
| return key != null ? key.getExportedName() : "<no name>"; |
| } |
| |
| @Override |
| public String getPrintableName() { |
| return getName(); |
| } |
| |
| @Override |
| public String getErrorMessageFormatForInstances() { |
| return errorMessageFormatForInstances; |
| } |
| |
| @Override |
| public void export(Label extensionLabel, String exportedName) { |
| Preconditions.checkState(!isExported()); |
| this.key = new SkylarkKey(extensionLabel, exportedName); |
| this.errorMessageFormatForInstances = |
| String.format("'%s' object has no attribute '%%s'", exportedName); |
| } |
| |
| @Override |
| public int hashCode() { |
| if (isExported()) { |
| return getKey().hashCode(); |
| } |
| return System.identityHashCode(this); |
| } |
| |
| @Override |
| public boolean equals(@Nullable Object otherObject) { |
| if (!(otherObject instanceof SkylarkProvider)) { |
| return false; |
| } |
| SkylarkProvider other = (SkylarkProvider) otherObject; |
| |
| if (this.isExported() && other.isExported()) { |
| return this.getKey().equals(other.getKey()); |
| } else { |
| return this == other; |
| } |
| } |
| |
| @Override |
| public boolean isImmutable() { |
| // Hash code for non exported constructors may be changed |
| return isExported(); |
| } |
| |
| @Override |
| public void repr(SkylarkPrinter printer) { |
| printer.append("<provider>"); |
| } |
| |
| /** |
| * A serializable representation of Skylark-defined {@link SkylarkProvider} that uniquely |
| * identifies all {@link SkylarkProvider}s that are exposed to SkyFrame. |
| */ |
| public static class SkylarkKey extends Key { |
| private final Label extensionLabel; |
| private final String exportedName; |
| |
| public SkylarkKey(Label extensionLabel, String exportedName) { |
| this.extensionLabel = Preconditions.checkNotNull(extensionLabel); |
| this.exportedName = Preconditions.checkNotNull(exportedName); |
| } |
| |
| public Label getExtensionLabel() { |
| return extensionLabel; |
| } |
| |
| public String getExportedName() { |
| return exportedName; |
| } |
| |
| @Override |
| public String toString() { |
| return exportedName; |
| } |
| |
| @Override |
| public int hashCode() { |
| return Objects.hash(extensionLabel, exportedName); |
| } |
| |
| @Override |
| public boolean equals(Object obj) { |
| if (this == obj) { |
| return true; |
| } |
| |
| if (!(obj instanceof SkylarkKey)) { |
| return false; |
| } |
| SkylarkKey other = (SkylarkKey) obj; |
| return Objects.equals(this.extensionLabel, other.extensionLabel) |
| && Objects.equals(this.exportedName, other.exportedName); |
| } |
| } |
| } |