Error Prone 2.0.21 release

[Eddie Aftandilian]

Error Prone 2.0.21 is now available for download from Maven Central.

(There release notes include all changes since 2.0.19.)

New features

• Added support for passing command-line flags to bug checkers.  See errorprone.info/docs/flags#pass-additional-info-to-bugcheckers for details (#524)

• Added -XepPatchImportOrder:<order> to control the import order when patchIng. Valid orders are “static-first”, “static-last”, “android-static-first”, and “android-static-last”

• Update to javac-9-dev-r4023-2 (#592)

New checks

• [ArgumentSelectionDefectChecker] Arguments are in the wrong order or could be commented for clarity

• [AssertEqualsArgumentOrderChecker] Arguments are swapped in assertEquals-like call

• [AutoValueConstructorOrderChecker] Arguments to AutoValue constructor are in the wrong order

• [ComparableAndComparator] Class should not implement both `Comparable` and `Comparator`

• [ConstructorInvokesOverridable] Constructors should not invoke overridable methods

• [ConstructorLeaksThis] Constructors should not pass the 'this' reference out in method invocations, since the object may not be fully constructed

• [InconsistentOverloads] The ordering of parameters in overloaded methods should be as consistent as possible (when viewed from left to right)

• [InstanceOfAndCastMatchWrongType] Casting inside an if block should be plausibly consistent with the instanceof type

• [IterablePathParameter] Path implements Iterable; prefer Collection for clarity

• [JavaLangClash] Never reuse class names from java.lang

• [LogicalAssignment] Assignment where a boolean expression was expected; use == if this assignment wasn't expected or add parentheses for clarity

• [NamedParameters] Parameter name in argument comment is missing or incorrect

• [NCopiesOfChar] The first argument to nCopies is the number of copies, and the second is the item to copy

• [NestedInstanceOfConditions] Nested instanceOf conditions of disjoint types create blocks of code that never execute

• [OvershadowingSubclassFields] Overshadowing variables of superclass causes confusion and errors

• [PredicateIncompatibleType] Using ::equals as an incompatible Predicate; the predicate will always return false

• [QualifierOrScopeOnInjectMethod] Qualifiers/Scope annotations on @Inject methods don't have any effect. Move the qualifier annotation to the binding location

• [ShouldHaveEvenArgs] This method must be called with an even number of arguments

• [UngroupedOverloads] Constructors and methods with the same name should appear sequentially with no other code in between

Bugs fixed

• -XepAllDisabledChecksAsWarnings now takes flag position into account (#486)

• Recognize safe try/finally/close patterns in MustBeClosedChecker (#489)

• Make well-known immutable and unsafe classes for Immutable checkers customizable with new-style command line flags (#512)

• Catch uses of Scanner in DefaultCharset (#603)

• Avoid subclassing CompilationTask in BaseErrorProneJavaCompiler (#608)

• Add second suggested fix to ArgumentSelectionDefectChecker which applies named comments to parameters (#609)

• Handle broken classpaths more gracefully in ImmutableAnalysis (#615)

• Fix inheritance of @Immutable annotations (#615)

• Fix issue where InstanceOfAndCastMatchWrongType was crashing on array accesses (#651)

Changes to existing checks

• [ArgumentParameterMismatch, ArgumentParameterSwap] Removed these and replaced with ArgumentSelectionDefectChecker

• [CheckReturnValue, FutureReturnValueIgnored, ReturnValueIgnored, PromiseReturnValueIgnored] Handle the case when a function is called in a lambda with a void return type

• [ElementsCountedInLoop] Removed this check

• [FormatMethod] Add support for constructors

• [FutureReturnValueIgnored] Downgrade from ERROR to WARNING

• [FutureReturnValueIgnored] Whitelist ChannelFuture#addListener(s)

• [GuardedBy] Support all annotations named 'GuardedBy'

• [JUnit3TestNotRun] Expand check to find non-public test methods.

• [JUnit4TestNotRun] Improve summary message

• [LiteralClassName] Downgrade from WARNING to SUGGESTION (#579)

• [LogicalAssignment] Downgrade from ERROR to WARNING

• [MutableConstantField] Replace declaration type regardless of the original declaration type

• [MutableConstantField] Do not suggest a fix when the declaration type is already immutable

• [MutableConstantField] Choose the new LHS type according to the original LHS type if possible, otherwise, use the RHS type

• [MutableConstantField] Fix references to Multimap and Multiset

• [NarrowingCompoundAssignment] Report errors for long-to-int conversions

• [ProtocolBufferOrdinal] Check when calling ordinal() on protobuf-lite enums as well as protobuf enums

• [ProtocolBufferOrdinal] Upgrade from WARNING to ERROR