Class SelfAssignment

java.lang.Object

com.google.errorprone.bugpatterns.BugChecker

com.google.errorprone.bugpatterns.SelfAssignment

All Implemented Interfaces:

BugChecker.AssignmentTreeMatcher, BugChecker.VariableTreeMatcher, Suppressible, Serializable

public class SelfAssignment
extends BugChecker
implements BugChecker.AssignmentTreeMatcher, BugChecker.VariableTreeMatcher

TODO(eaftan): Consider cases where the parent is not a statement or there is no parent?

Author:

eaftan@google.com (Eddie Aftandilian), scottjohnson@google.com (Scott Johnson)

See Also:

• Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class com.google.errorprone.bugpatterns.BugChecker

BugChecker.AnnotatedTypeTreeMatcher, BugChecker.AnnotationTreeMatcher, BugChecker.ArrayAccessTreeMatcher, BugChecker.ArrayTypeTreeMatcher, BugChecker.AssertTreeMatcher, BugChecker.AssignmentTreeMatcher, BugChecker.BinaryTreeMatcher, BugChecker.BlockTreeMatcher, BugChecker.BreakTreeMatcher, BugChecker.CaseTreeMatcher, BugChecker.CatchTreeMatcher, BugChecker.ClassTreeMatcher, BugChecker.CompilationUnitTreeMatcher, BugChecker.CompoundAssignmentTreeMatcher, BugChecker.ConditionalExpressionTreeMatcher, BugChecker.ContinueTreeMatcher, BugChecker.DoWhileLoopTreeMatcher, BugChecker.EmptyStatementTreeMatcher, BugChecker.EnhancedForLoopTreeMatcher, BugChecker.ExpressionStatementTreeMatcher, BugChecker.ForLoopTreeMatcher, BugChecker.IdentifierTreeMatcher, BugChecker.IfTreeMatcher, BugChecker.ImportTreeMatcher, BugChecker.InstanceOfTreeMatcher, BugChecker.IntersectionTypeTreeMatcher, BugChecker.LabeledStatementTreeMatcher, BugChecker.LambdaExpressionTreeMatcher, BugChecker.LiteralTreeMatcher, BugChecker.MemberReferenceTreeMatcher, BugChecker.MemberSelectTreeMatcher, BugChecker.MethodInvocationTreeMatcher, BugChecker.MethodTreeMatcher, BugChecker.ModifiersTreeMatcher, BugChecker.NewArrayTreeMatcher, BugChecker.NewClassTreeMatcher, BugChecker.ParameterizedTypeTreeMatcher, BugChecker.ParenthesizedTreeMatcher, BugChecker.PrimitiveTypeTreeMatcher, BugChecker.ReturnTreeMatcher, BugChecker.SuppressibleTreePathScanner<R,P>, BugChecker.SwitchTreeMatcher, BugChecker.SynchronizedTreeMatcher, BugChecker.ThrowTreeMatcher, BugChecker.TryTreeMatcher, BugChecker.TypeCastTreeMatcher, BugChecker.TypeParameterTreeMatcher, BugChecker.UnaryTreeMatcher, BugChecker.UnionTypeTreeMatcher, BugChecker.VariableTreeMatcher, BugChecker.WhileLoopTreeMatcher, BugChecker.WildcardTreeMatcher

Constructor Summary

Constructors

Constructor	Description
SelfAssignment()

Method Summary

Modifier and Type	Method	Description
Description	describeForAssignment(com.sun.source.tree.AssignmentTree assignmentTree, VisitorState state)	We expect that the lhs is a field and the rhs is an identifier, specifically a parameter to the method.
Description	describeForVarDecl(com.sun.source.tree.VariableTree tree, VisitorState state)
Description	matchAssignment(com.sun.source.tree.AssignmentTree tree, VisitorState state)
Description	matchVariable(com.sun.source.tree.VariableTree tree, VisitorState state)

Methods inherited from class com.google.errorprone.bugpatterns.BugChecker

allNames, buildDescription, buildDescription, buildDescription, canonicalName, customSuppressionAnnotations, defaultSeverity, describeMatch, describeMatch, describeMatch, describeMatch, describeMatch, describeMatch, disableable, equals, hashCode, isSuppressed, isSuppressed, isSuppressed, isSuppressed, linkUrl, message, supportsSuppressWarnings, suppressedByAnyOf, suppressedRegions

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface com.google.errorprone.matchers.Suppressible

allNames, canonicalName, customSuppressionAnnotations, supportsSuppressWarnings, suppressedByAnyOf

Constructor Details

SelfAssignment

public SelfAssignment()

Method Details

matchAssignment

public Description matchAssignment(com.sun.source.tree.AssignmentTree tree,
 VisitorState state)

Specified by:

matchAssignment in interface BugChecker.AssignmentTreeMatcher

matchVariable

public Description matchVariable(com.sun.source.tree.VariableTree tree,
 VisitorState state)

Specified by:

matchVariable in interface BugChecker.VariableTreeMatcher

describeForVarDecl

public Description describeForVarDecl(com.sun.source.tree.VariableTree tree,
 VisitorState state)

describeForAssignment

public Description describeForAssignment(com.sun.source.tree.AssignmentTree assignmentTree,
 VisitorState state)

We expect that the lhs is a field and the rhs is an identifier, specifically a parameter to the method. We base our suggested fixes on this expectation.

Case 1: If lhs is a field and rhs is an identifier, find a method parameter of the same type and similar name and suggest it as the rhs. (Guess that they have misspelled the identifier.)

Case 2: If lhs is a field and rhs is not an identifier, find a method parameter of the same type and similar name and suggest it as the rhs.

Case 3: If lhs is not a field and rhs is an identifier, find a class field of the same type and similar name and suggest it as the lhs.

Case 4: Otherwise suggest deleting the assignment.