| /* |
| * Copyright (C) 2012 The Android Open Source Project |
| * |
| * 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.android.tools.lint.checks; |
| |
| import static com.android.SdkConstants.RESOURCE_CLZ_ID; |
| import static com.android.tools.lint.checks.ViewTypeDetector.FIND_VIEW_BY_ID; |
| import static com.android.tools.lint.checks.ViewTypeDetector.REQUIRE_VIEW_BY_ID; |
| |
| import com.android.annotations.NonNull; |
| import com.android.annotations.Nullable; |
| import com.android.tools.lint.detector.api.Category; |
| import com.android.tools.lint.detector.api.Context; |
| import com.android.tools.lint.detector.api.Detector; |
| import com.android.tools.lint.detector.api.Implementation; |
| import com.android.tools.lint.detector.api.Issue; |
| import com.android.tools.lint.detector.api.JavaContext; |
| import com.android.tools.lint.detector.api.Location; |
| import com.android.tools.lint.detector.api.Scope; |
| import com.android.tools.lint.detector.api.Severity; |
| import com.android.tools.lint.detector.api.SourceCodeScanner; |
| import com.google.common.collect.Maps; |
| import com.intellij.psi.PsiMethod; |
| import java.util.Arrays; |
| import java.util.List; |
| import java.util.Map; |
| import org.jetbrains.uast.UArrayAccessExpression; |
| import org.jetbrains.uast.UBinaryExpression; |
| import org.jetbrains.uast.UBlockExpression; |
| import org.jetbrains.uast.UBreakExpression; |
| import org.jetbrains.uast.UCallExpression; |
| import org.jetbrains.uast.UContinueExpression; |
| import org.jetbrains.uast.UDoWhileExpression; |
| import org.jetbrains.uast.UElement; |
| import org.jetbrains.uast.UExpression; |
| import org.jetbrains.uast.UForEachExpression; |
| import org.jetbrains.uast.UForExpression; |
| import org.jetbrains.uast.UIfExpression; |
| import org.jetbrains.uast.ULabeledExpression; |
| import org.jetbrains.uast.ULocalVariable; |
| import org.jetbrains.uast.ULoopExpression; |
| import org.jetbrains.uast.UMethod; |
| import org.jetbrains.uast.UQualifiedReferenceExpression; |
| import org.jetbrains.uast.UReferenceExpression; |
| import org.jetbrains.uast.UReturnExpression; |
| import org.jetbrains.uast.USwitchExpression; |
| import org.jetbrains.uast.UWhileExpression; |
| import org.jetbrains.uast.UastUtils; |
| import org.jetbrains.uast.util.UastExpressionUtils; |
| import org.jetbrains.uast.visitor.AbstractUastVisitor; |
| |
| /** Detector looking for cut & paste issues */ |
| public class CutPasteDetector extends Detector implements SourceCodeScanner { |
| /** The main issue discovered by this detector */ |
| public static final Issue ISSUE = |
| Issue.create( |
| "CutPasteId", |
| "Likely cut & paste mistakes", |
| "This lint check looks for cases where you have cut & pasted calls to " |
| + "`findViewById` but have forgotten to update the R.id field. It's possible " |
| + "that your code is simply (redundantly) looking up the field repeatedly, " |
| + "but lint cannot distinguish that from a case where you for example want to " |
| + "initialize fields `prev` and `next` and you cut & pasted `findViewById(R.id.prev)` " |
| + "and forgot to update the second initialization to `R.id.next`.", |
| Category.CORRECTNESS, |
| 6, |
| Severity.WARNING, |
| new Implementation(CutPasteDetector.class, Scope.JAVA_FILE_SCOPE)) |
| .setAndroidSpecific(true); |
| |
| private PsiMethod lastMethod; |
| private Map<String, UCallExpression> ids; |
| private Map<String, String> lhs; |
| private Map<String, String> callOperands; |
| |
| /** Constructs a new {@link CutPasteDetector} check */ |
| public CutPasteDetector() {} |
| |
| // ---- implements SourceCodeScanner ---- |
| |
| @Override |
| public List<String> getApplicableMethodNames() { |
| return Arrays.asList(FIND_VIEW_BY_ID, REQUIRE_VIEW_BY_ID); |
| } |
| |
| @Override |
| public void visitMethodCall( |
| @NonNull JavaContext context, |
| @NonNull UCallExpression call, |
| @NonNull PsiMethod calledMethod) { |
| // If it's in a comparison, don't do anything |
| if (call.getUastParent() instanceof UBinaryExpression |
| && !UastExpressionUtils.isAssignment(call.getUastParent())) { |
| return; |
| } |
| |
| String leftSide = getLhs(call); |
| if (leftSide == null) { |
| return; |
| } |
| |
| UMethod method = UastUtils.getParentOfType(call, UMethod.class, false); |
| if (method == null) { |
| return; // prevent doing the same work for multiple findViewById calls in same method |
| } else if (method != lastMethod) { |
| ids = Maps.newHashMap(); |
| lhs = Maps.newHashMap(); |
| callOperands = Maps.newHashMap(); |
| lastMethod = method; |
| } |
| |
| String callOperand = call.getReceiver() != null ? call.getReceiver().asSourceString() : ""; |
| |
| List<UExpression> arguments = call.getValueArguments(); |
| if (arguments.isEmpty()) { |
| return; |
| } |
| UExpression first = arguments.get(0); |
| if (first instanceof UReferenceExpression) { |
| UReferenceExpression psiReferenceExpression = (UReferenceExpression) first; |
| String id = psiReferenceExpression.getResolvedName(); |
| UElement operand = |
| (first instanceof UQualifiedReferenceExpression) |
| ? ((UQualifiedReferenceExpression) first).getReceiver() |
| : null; |
| |
| if (operand instanceof UReferenceExpression) { |
| UReferenceExpression type = (UReferenceExpression) operand; |
| if (RESOURCE_CLZ_ID.equals(type.getResolvedName())) { |
| if (ids.containsKey(id)) { |
| if (leftSide.equals(this.lhs.get(id))) { |
| return; |
| } |
| if (!callOperand.equals(callOperands.get(id))) { |
| return; |
| } |
| UCallExpression earlierCall = ids.get(id); |
| if (!isReachableFrom(method, earlierCall, call)) { |
| return; |
| } |
| Location location = context.getLocation(call); |
| Location secondary = context.getLocation(earlierCall); |
| secondary.setMessage("First usage here"); |
| location.setSecondary(secondary); |
| context.report( |
| ISSUE, |
| call, |
| location, |
| String.format( |
| "The id `%1$s` has already been looked up in this method; possible " |
| + "cut & paste error?", |
| first.asSourceString())); |
| } else { |
| ids.put(id, call); |
| lhs.put(id, leftSide); |
| callOperands.put(id, callOperand); |
| } |
| } |
| } |
| } |
| } |
| |
| @Override |
| public void afterCheckFile(@NonNull Context context) { |
| ids = null; |
| lhs = null; |
| callOperands = null; |
| lastMethod = null; |
| } |
| |
| @Nullable |
| private static String getLhs(@NonNull UCallExpression call) { |
| UElement parent = call.getUastParent(); |
| while (parent != null && !(parent instanceof UBlockExpression)) { |
| if (parent instanceof ULocalVariable) { |
| return ((ULocalVariable) parent).getName(); |
| } else if (UastExpressionUtils.isAssignment(parent)) { |
| UExpression left = ((UBinaryExpression) parent).getLeftOperand(); |
| if (left instanceof UReferenceExpression) { |
| return left.asSourceString(); |
| } else if (left instanceof UArrayAccessExpression) { |
| UArrayAccessExpression aa = (UArrayAccessExpression) left; |
| return aa.getReceiver().asSourceString(); |
| } |
| } |
| parent = parent.getUastParent(); |
| } |
| return null; |
| } |
| |
| static boolean isReachableFrom( |
| @NonNull UMethod method, @NonNull UElement from, @NonNull UElement to) { |
| ReachabilityVisitor visitor = new ReachabilityVisitor(from, to); |
| method.accept(visitor); |
| return visitor.isReachable(); |
| } |
| |
| private static class ReachabilityVisitor extends AbstractUastVisitor { |
| |
| private final UElement from; |
| private final UElement target; |
| |
| private boolean isFromReached; |
| private boolean isTargetReachable; |
| private boolean isFinished; |
| |
| private UExpression breakedExpression; |
| private UExpression continuedExpression; |
| |
| ReachabilityVisitor(UElement from, UElement target) { |
| this.from = from; |
| this.target = target; |
| } |
| |
| @Override |
| public boolean visitElement(UElement node) { |
| if (isFinished || breakedExpression != null || continuedExpression != null) { |
| return true; |
| } |
| |
| if (node.equals(from)) { |
| isFromReached = true; |
| } |
| |
| if (node.equals(target)) { |
| isFinished = true; |
| if (isFromReached) { |
| isTargetReachable = true; |
| } |
| return true; |
| } |
| |
| if (isFromReached) { |
| if (node instanceof UReturnExpression) { |
| isFinished = true; |
| } else if (node instanceof UBreakExpression) { |
| breakedExpression = getBreakedExpression((UBreakExpression) node); |
| } else if (node instanceof UContinueExpression) { |
| UExpression expression = getContinuedExpression((UContinueExpression) node); |
| if (expression != null && UastUtils.isChildOf(target, expression, false)) { |
| isTargetReachable = true; |
| isFinished = true; |
| } else { |
| continuedExpression = expression; |
| } |
| } else if (UastUtils.isChildOf(target, node, false)) { |
| isTargetReachable = true; |
| isFinished = true; |
| } |
| return true; |
| } else { |
| if (node instanceof UIfExpression) { |
| UIfExpression ifExpression = (UIfExpression) node; |
| |
| ifExpression.getCondition().accept(this); |
| |
| boolean isFromReached = this.isFromReached; |
| |
| UExpression thenExpression = ifExpression.getThenExpression(); |
| if (thenExpression != null) { |
| thenExpression.accept(this); |
| } |
| |
| UExpression elseExpression = ifExpression.getElseExpression(); |
| if (elseExpression != null && isFromReached == this.isFromReached) { |
| elseExpression.accept(this); |
| } |
| return true; |
| } else if (node instanceof ULoopExpression) { |
| visitLoopExpressionHeader(node); |
| boolean isFromReached = this.isFromReached; |
| |
| ((ULoopExpression) node).getBody().accept(this); |
| |
| if (isFromReached != this.isFromReached |
| && UastUtils.isChildOf(target, node, false)) { |
| isTargetReachable = true; |
| isFinished = true; |
| } |
| return true; |
| } |
| } |
| |
| return false; |
| } |
| |
| @Override |
| public void afterVisitElement(UElement node) { |
| if (node.equals(breakedExpression)) { |
| breakedExpression = null; |
| } else if (node.equals(continuedExpression)) { |
| continuedExpression = null; |
| } |
| } |
| |
| private void visitLoopExpressionHeader(UElement node) { |
| if (node instanceof UWhileExpression) { |
| ((UWhileExpression) node).getCondition().accept(this); |
| } else if (node instanceof UDoWhileExpression) { |
| ((UDoWhileExpression) node).getCondition().accept(this); |
| } else if (node instanceof UForExpression) { |
| UForExpression forExpression = (UForExpression) node; |
| |
| if (forExpression.getDeclaration() != null) { |
| forExpression.getDeclaration().accept(this); |
| } |
| |
| if (forExpression.getCondition() != null) { |
| forExpression.getCondition().accept(this); |
| } |
| |
| if (forExpression.getUpdate() != null) { |
| forExpression.getUpdate().accept(this); |
| } |
| } else if (node instanceof UForEachExpression) { |
| UForEachExpression forEachExpression = (UForEachExpression) node; |
| forEachExpression.getForIdentifier().accept(this); |
| forEachExpression.getIteratedValue().accept(this); |
| } |
| } |
| |
| private static UExpression getBreakedExpression(UBreakExpression node) { |
| UElement parent = node.getUastParent(); |
| String label = node.getLabel(); |
| while (parent != null) { |
| if (label != null) { |
| if (parent instanceof ULabeledExpression) { |
| ULabeledExpression labeledExpression = (ULabeledExpression) parent; |
| if (labeledExpression.getLabel().equals(label)) { |
| return labeledExpression.getExpression(); |
| } |
| } |
| } else { |
| if (parent instanceof ULoopExpression || parent instanceof USwitchExpression) { |
| return (UExpression) parent; |
| } |
| } |
| parent = parent.getUastParent(); |
| } |
| return null; |
| } |
| |
| private static UExpression getContinuedExpression(UContinueExpression node) { |
| UElement parent = node.getUastParent(); |
| String label = node.getLabel(); |
| while (parent != null) { |
| if (label != null) { |
| if (parent instanceof ULabeledExpression) { |
| ULabeledExpression labeledExpression = (ULabeledExpression) parent; |
| if (labeledExpression.getLabel().equals(label)) { |
| return labeledExpression.getExpression(); |
| } |
| } |
| } else { |
| if (parent instanceof ULoopExpression) { |
| return (UExpression) parent; |
| } |
| } |
| parent = parent.getUastParent(); |
| } |
| return null; |
| } |
| |
| public boolean isReachable() { |
| return isTargetReachable; |
| } |
| } |
| } |
