001 /*
002 * Copyright 2010-2015 JetBrains s.r.o.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 * http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017 package org.jetbrains.kotlin.resolve;
018
019 import com.google.common.collect.Sets;
020 import com.intellij.openapi.util.Pair;
021 import com.intellij.util.containers.MultiMap;
022 import org.jetbrains.annotations.NotNull;
023 import org.jetbrains.kotlin.descriptors.*;
024 import org.jetbrains.kotlin.diagnostics.Errors;
025 import org.jetbrains.kotlin.idea.MainFunctionDetector;
026 import org.jetbrains.kotlin.name.FqNameUnsafe;
027 import org.jetbrains.kotlin.name.Name;
028 import org.jetbrains.kotlin.psi.*;
029
030 import java.util.Collection;
031 import java.util.Map;
032 import java.util.Set;
033
034 import static org.jetbrains.kotlin.resolve.DescriptorUtils.getFqName;
035
036 public class OverloadResolver {
037 @NotNull private final BindingTrace trace;
038 @NotNull private final MainFunctionDetector mainFunctionDetector;
039
040 public OverloadResolver(@NotNull BindingTrace trace) {
041 this.trace = trace;
042 mainFunctionDetector = new MainFunctionDetector(trace.getBindingContext());
043 }
044
045 public void process(@NotNull BodiesResolveContext c) {
046 checkOverloads(c);
047 }
048
049 private void checkOverloads(@NotNull BodiesResolveContext c) {
050 MultiMap<ClassDescriptor, ConstructorDescriptor> inClasses = MultiMap.create();
051 MultiMap<FqNameUnsafe, ConstructorDescriptor> inPackages = MultiMap.create();
052 fillGroupedConstructors(c, inClasses, inPackages);
053
054 for (Map.Entry<KtClassOrObject, ClassDescriptorWithResolutionScopes> entry : c.getDeclaredClasses().entrySet()) {
055 checkOverloadsInAClass(entry.getValue(), entry.getKey(), inClasses.get(entry.getValue()));
056 }
057 checkOverloadsInPackages(c, inPackages);
058 }
059
060 private static void fillGroupedConstructors(
061 @NotNull BodiesResolveContext c,
062 @NotNull MultiMap<ClassDescriptor, ConstructorDescriptor> inClasses,
063 @NotNull MultiMap<FqNameUnsafe, ConstructorDescriptor> inPackages
064 ) {
065 for (ClassDescriptorWithResolutionScopes klass : c.getDeclaredClasses().values()) {
066 if (klass.getKind().isSingleton() || klass.getName().isSpecial()) {
067 // Constructors of singletons or anonymous object aren't callable from the code, so they shouldn't participate in overload name checking
068 continue;
069 }
070 DeclarationDescriptor containingDeclaration = klass.getContainingDeclaration();
071 if (containingDeclaration instanceof ClassDescriptor) {
072 ClassDescriptor classDescriptor = (ClassDescriptor) containingDeclaration;
073 inClasses.putValues(classDescriptor, klass.getConstructors());
074 }
075 else if (containingDeclaration instanceof PackageFragmentDescriptor) {
076 inPackages.putValues(getFqName(klass), klass.getConstructors());
077 }
078 else if (containingDeclaration instanceof ScriptDescriptor) {
079 // TODO: check overload conflicts of functions with constructors in scripts
080 }
081 else if (!(containingDeclaration instanceof FunctionDescriptor)) {
082 throw new IllegalStateException("Illegal class container: " + containingDeclaration);
083 }
084 }
085 }
086
087 private void checkOverloadsInPackages(
088 @NotNull BodiesResolveContext c,
089 @NotNull MultiMap<FqNameUnsafe, ConstructorDescriptor> inPackages
090 ) {
091 MultiMap<FqNameUnsafe, CallableMemberDescriptor> membersByName = OverloadUtil.groupModulePackageMembersByFqName(c, inPackages);
092
093 for (Map.Entry<FqNameUnsafe, Collection<CallableMemberDescriptor>> e : membersByName.entrySet()) {
094 FqNameUnsafe fqName = e.getKey().parent();
095 checkOverloadsInPackage(e.getValue(), fqName);
096 }
097 }
098
099 private static String nameForErrorMessage(ClassDescriptor classDescriptor, KtClassOrObject jetClass) {
100 String name = jetClass.getName();
101 if (name != null) {
102 return name;
103 }
104 if (jetClass instanceof KtObjectDeclaration) {
105 // must be companion object
106 name = classDescriptor.getContainingDeclaration().getName().asString();
107 return "companion object " + name;
108 }
109 // safe
110 return "<unknown>";
111 }
112
113 private void checkOverloadsInAClass(
114 ClassDescriptorWithResolutionScopes classDescriptor, KtClassOrObject klass,
115 Collection<ConstructorDescriptor> nestedClassConstructors
116 ) {
117 MultiMap<Name, CallableMemberDescriptor> functionsByName = MultiMap.create();
118
119 for (CallableMemberDescriptor function : classDescriptor.getDeclaredCallableMembers()) {
120 functionsByName.putValue(function.getName(), function);
121 }
122
123 for (ConstructorDescriptor nestedClassConstructor : nestedClassConstructors) {
124 functionsByName.putValue(nestedClassConstructor.getContainingDeclaration().getName(), nestedClassConstructor);
125 }
126
127 for (Map.Entry<Name, Collection<CallableMemberDescriptor>> e : functionsByName.entrySet()) {
128 checkOverloadsInClass(e.getValue(), classDescriptor, klass);
129 }
130 }
131
132 private void checkOverloadsInPackage(
133 @NotNull Collection<CallableMemberDescriptor> members,
134 @NotNull FqNameUnsafe packageFQN
135 ) {
136 if (members.size() == 1) return;
137
138 for (Collection<? extends CallableMemberDescriptor> redeclarationGroup : OverloadUtil.getPossibleRedeclarationGroups(members)) {
139 Set<Pair<KtDeclaration, CallableMemberDescriptor>> redeclarations = findRedeclarations(redeclarationGroup);
140 // TODO: don't render FQ name here, extract this logic to somewhere
141 reportRedeclarations(packageFQN.isRoot() ? "root package" : packageFQN.asString(), redeclarations);
142 }
143 }
144
145 private void checkOverloadsInClass(
146 @NotNull Collection<CallableMemberDescriptor> members,
147 @NotNull ClassDescriptor classDescriptor,
148 @NotNull KtClassOrObject ktClass
149 ) {
150 if (members.size() == 1) return;
151
152 reportRedeclarations(nameForErrorMessage(classDescriptor, ktClass), findRedeclarations(members));
153 }
154
155 @NotNull
156 private Set<Pair<KtDeclaration, CallableMemberDescriptor>> findRedeclarations(@NotNull Collection<? extends CallableMemberDescriptor> members) {
157 Set<Pair<KtDeclaration, CallableMemberDescriptor>> redeclarations = Sets.newLinkedHashSet();
158 for (CallableMemberDescriptor member : members) {
159 for (CallableMemberDescriptor member2 : members) {
160 if (member == member2 || isConstructorsOfDifferentRedeclaredClasses(member, member2)) {
161 continue;
162 }
163
164 if (!OverloadUtil.isOverloadable(member, member2) && member.getKind() != CallableMemberDescriptor.Kind.SYNTHESIZED) {
165 if (isTopLevelMainInDifferentFiles(member, member2)) {
166 continue;
167 }
168
169 KtDeclaration ktDeclaration = (KtDeclaration) DescriptorToSourceUtils.descriptorToDeclaration(member);
170 if (ktDeclaration != null) {
171 redeclarations.add(Pair.create(ktDeclaration, member));
172 }
173 }
174 }
175 }
176 return redeclarations;
177 }
178
179 private static boolean isConstructorsOfDifferentRedeclaredClasses(
180 @NotNull CallableMemberDescriptor member, @NotNull CallableMemberDescriptor member2
181 ) {
182 if (!(member instanceof ConstructorDescriptor) || !(member2 instanceof ConstructorDescriptor)) return false;
183 // ignore conflicting overloads for constructors of different classes because their redeclarations will be reported
184 // but don't ignore if there's possibility that classes redeclarations will not be reported
185 // (e.g. they're declared in different packages)
186 assert member.getContainingDeclaration().getContainingDeclaration() != null : "Grandparent of constructor should not be null";
187 return member.getContainingDeclaration() != member2.getContainingDeclaration() &&
188 member.getContainingDeclaration().getContainingDeclaration().equals(member2.getContainingDeclaration().getContainingDeclaration());
189 }
190
191 private boolean isTopLevelMainInDifferentFiles(@NotNull CallableMemberDescriptor member, @NotNull CallableMemberDescriptor member2) {
192 if (!DescriptorToSourceUtils.isTopLevelMainFunction(member, mainFunctionDetector) ||
193 !DescriptorToSourceUtils.isTopLevelMainFunction(member2, mainFunctionDetector)) {
194 return false;
195 }
196
197 return DescriptorToSourceUtils.getContainingFile(member) != DescriptorToSourceUtils.getContainingFile(member2);
198 }
199
200 private void reportRedeclarations(@NotNull String functionContainer,
201 @NotNull Set<Pair<KtDeclaration, CallableMemberDescriptor>> redeclarations) {
202 for (Pair<KtDeclaration, CallableMemberDescriptor> redeclaration : redeclarations) {
203 CallableMemberDescriptor memberDescriptor = redeclaration.getSecond();
204
205 KtDeclaration ktDeclaration = redeclaration.getFirst();
206 if (memberDescriptor instanceof PropertyDescriptor) {
207 trace.report(Errors.REDECLARATION.on(ktDeclaration, memberDescriptor.getName().asString()));
208 }
209 else {
210 String containingClassName = ktDeclaration instanceof KtSecondaryConstructor ?
211 ((KtSecondaryConstructor) ktDeclaration).getContainingClassOrObject().getName() : null;
212
213 trace.report(Errors.CONFLICTING_OVERLOADS.on(
214 ktDeclaration, memberDescriptor,
215 containingClassName != null ? containingClassName : functionContainer));
216 }
217 }
218 }
219 }