Error Prone 2.3.3

New checks:

• AssignmentToMock: Fields annotated with @mock should not be manually assigned to.
• AutoValueImmutableFields: AutoValue recommends using immutable collections
• CompareToZero: The result of #compareTo or #compare should only be compared to 0. It is an implementation detail whether a given type returns strictly the values {-1, 0, +1} or others.
• DeduplicateConstants: This expression was previously declared as a constant; consider replacing this occurrence.
• DiscardedPostfixExpression: The result of this unary operation on a lambda parameter is discarded
• DuplicateMapKeys: Map#ofEntries will throw an IllegalArgumentException if there are any duplicate keys
• EscapedEntity: HTML entities in @code/@literal tags will appear literally in the rendered javadoc.
• InheritDoc: Invalid use of @inheritdoc.
• InterfaceWithOnlyStatics: This interface only contains static fields and methods; consider making it a final class instead to prevent subclassing.
• InvalidBlockTag: This tag is invalid.
• InvalidInlineTag: This tag is invalid.
• MissingSummary: A summary line is required on public/protected Javadocs.
• MixedDescriptors: The field number passed into #getFieldByNumber belongs to a different proto to the Descriptor.
• MixedMutabilityReturnType: This method returns both mutable and immutable collections or maps from different paths. This may be confusing for users of the method.
• MockitoInternalUsage: org.mockito.internal.* is a private API and should not be used by clients
• OptionalMapToOptional: Mapping to another Optional will yield a nested Optional. Did you mean flatMap?
• OutlineNone: Setting CSS outline style to none or 0 (while not otherwise providing visual focus indicators) is inaccessible for users navigating a web page without a mouse.
• PreconditionsCheckNotNullRepeated: Including the first argument of checkNotNull in the failure message is not useful, as it will always be null.
• RedundantOverride: This override is redundant, and can be removed.
• RefersToDaggerCodegen: Don't refer to Dagger's internal or generated code
• RxReturnValueIgnored: Returned Rx objects must be checked. Ignoring a returned Rx value means it is never scheduled for execution
• TreeToString: Tree#toString shouldn't be used for Trees deriving from the code being compiled, as it discards whitespace and comments.
• TypeEquals: com.sun.tools.javac.code.Type doesn't override Object.equals and instances are not interned by javac, so testing types for equality should be done with Types#isSameType instead
• UnescapedEntity: Javadoc is interpreted as HTML, so HTML entities such as &, <, > must be escaped.
• UnusedMethod: Unused.
• UnusedNestedClass: This nested class is unused, and can be removed.
• UnusedVariable: Unused.

New date and time related checks:

• JavaDurationGetSecondsGetNano: duration.getNano() only accesses the underlying nanosecond adjustment from the whole second.
• JavaDurationWithNanos: Use of java.time.Duration.withNanos(int) is not allowed.
• JavaDurationWithSeconds: Use of java.time.Duration.withSeconds(long) is not allowed.
• JavaInstantGetSecondsGetNano: instant.getNano() only accesses the underlying nanosecond adjustment from the whole second.
• JavaTimeDefaultTimeZone: java.time APIs that silently use the default system time-zone are not allowed.
• JodaDurationConstructor: Use of new Duration(long) is not allowed. Please use Duration.millis(long) instead.
• JodaDurationWithMillis: Use of duration.withMillis(long) is not allowed. Please use Duration.millis(long) instead.
• JodaInstantWithMillis: Use of instant.withMillis(long) is not allowed. Please use new Instant(long) instead.
• JodaNewPeriod: This may have surprising semantics, e.g. new Period(LocalDate.parse("1970-01-01"), LocalDate.parse("1970-02-02")).getDays() == 1, not 32.
• JodaPlusMinusLong: Use of JodaTime's type.plus(long) or type.minus(long) is not allowed (where = {Duration,Instant,DateTime,DateMidnight}). Please use type.plus(Duration.millis(long)) or type.minus(Duration.millis(long)) instead.
• JodaTimeConverterManager: Joda-Time's ConverterManager makes the semantics of DateTime/Instant/etc construction subject to global static state. If you need to define your own converters, use a helper.
• JodaToSelf: Use of Joda-Time's DateTime.toDateTime(), Duration.toDuration(), Instant.toInstant(), Interval.toInterval(), and Period.toPeriod() are not allowed.
• JodaWithDurationAddedLong: Use of JodaTime's type.withDurationAdded(long, int) (where = {Duration,Instant,DateTime}). Please use type.withDurationAdded(Duration.millis(long), int) instead.
• TemporalAccessorGetChronoField: TemporalAccessor.get() only works for certain values of ChronoField.
• TimeUnitConversionChecker: This TimeUnit conversion looks buggy: converting from a smaller unit to a larger unit (and passing a constant), converting to/from the same TimeUnit, or converting TimeUnits where the result is statically known to be 0 or 1 are all buggy patterns.
• DurationFrom: Duration.from(Duration) returns itself; from(Period) throws a runtime exception.
• DurationGetTemporalUnit: Duration.get() only works with SECONDS or NANOS.
• DurationToLongTimeUnit: Unit mismatch when decomposing a Duration or Instant to call a <long, TimeUnit> API
• InvalidZoneId: Invalid zone identifier. ZoneId.of(String) will throw exception at runtime.
• PeriodFrom: Period.from(Period) returns itself; from(Duration) throws a runtime exception.
• PeriodGetTemporalUnit: Period.get() only works with YEARS, MONTHS, or DAYS.
• PeriodTimeMath: When adding or subtracting from a Period, Duration is incompatible.
• ProtoDurationGetSecondsGetNano: getNanos() only accesses the underlying nanosecond-adjustment of the duration.
• ProtoTimestampGetSecondsGetNano: getNanos() only accesses the underlying nanosecond-adjustment of the instant.
• ProtoTruthMixedDescriptors: The arguments passed to ignoringFields are inconsistent with the proto which is the subject of the assertion.
• TimeUnitMismatch: An value that appears to be represented in one unit is used where another appears to be required (e.g., seconds where nanos are needed)

API changes:

• @BugPattern.category is no longer supported; prefer @BugPattern.tags as a means to apply general tags to checks.

Other changes:

• Suppress checks thoroughly when -XepDisableWarningsInGeneratedCode is passed.
• Make UnusedVariable match unused assignments too.
• Handle static methods in InfiniteRecursion
• Add common java.time types to ReturnValueIgnored.
• ModifiedButNotUsed: match orphaned chains of proto/collection builders
• Improve NarrowingCompoundAssignment's fixes for ternary
• Allow suppressing AutoValueImmutableFields at the field level rather than just for the entire class...

Error Prone 2.3.2

Highlights:

• Opt-in check AndroidJdkLibsChecker enforces which JDK libraries can be used in Android applications, and, with the -XepOpt:Android:Java8Libs flag, can allow select Java 8 library support via https://developer.android.com/studio/write/java8-support. Look out for this in bazel.build after the next release.
• Immutable{Annotation,Enum}Checker now requires the Error Prone @Immutable annotation, not the JSR-305 @Immutable annotation

New Checks:

• Javadoc Checkers: InvalidParam, InvalidTag, InvalidThrows, ReturnFromVoid
• API Checkers: AndroidJdkLibsChecker, Java7ApiChecker, ApiDiffChecker
• AnnotateFormatMethod
• AnnotationPosition
• ArrayAsKeyOfSetOrMap
• AutoValueFinalMethods
• BadInstanceof
• BigDecimalEquals
• ClassNamedLikeTypeParameter
• CloseableProvides
• ComparingThisWithNull
• DeprecatedThreadMethods
• EqualsBrokenForNull
• EqualsGetClass
• EqualsUnsafeCast
• EqualsUsingHashCode
• EqualsWrongThing
• ExpectedExceptionRefactoring
• ExtendingJUnitAssert
• FloatingPointAssertionWithinEpsilon
• ImmutableRefactoring
• InconsistentHashCode
• InjectOnMemberAndConstructor
• LockNotBeforeTry
• MathAbsoluteRandom
• MathRoundIntLong
• MissingTestCall
• ModifiedButNotUsed
• NoFunctionalReturnType
• NullableDereference
• ObjectsHashCodePrimitive
• ProtoRedundantSet
• ProtosAsKeyOfSetOrMap
• SubstringOfZero
• SwigMemoryLeak
• SystemExitOutsideMain
• TestExceptionRefactoring
• ThreadPriorityCheck
• ToStringReturnsNull
• TruthAssertExpected
• TypeNameShadowing
• UndefinedEquals
• UnnecessaryParentheses
• UnsafeReflectiveConstructionCast
• UnusedException
• VariableNameSameAsType

Fixes Issues:

#1008, #1028, #1038, #1040, #1077, #1078, #1079, #1083, #1084, #1085, #1095, #1096, #1101, #1125, #1129, #1130, #35, #607, #783, #849, #926

Error Prone 2.3.1

New checks:

• [AssertThrowsMultipleStatements] The lambda passed to assertThows should contain exactly one statement
• [FieldCanBeFinal] This field is only assigned during initialization; consider making it final
• [ObjectToString] Calling toString on Objects that don't override toString() doesn't provide useful information

Other changes:

• Make ParcelableCreator check an ERROR
• OrphanedFormatString detects string literals correctly passed to @FormatMethod methods

Fixes issues: #996, #999, #1001, #1004

Error Prone 2.3.0

New checks:

• [ParcelableCreator]: Detects classes which implement Parcelable but don't have CREATOR
• [InconsistentCapitalization] It is confusing to have a field and a parameter under the same scope that differ only in capitalization
• [TruthIncompatibleType] Argument is not compatible with the subject's type
• [ByteBufferBackingArray] ByteBuffer.array() shouldn't be called unless ByteBuffer.arrayOffset() is used or if the ByteBuffer was initialized using ByteBuffer.wrap() or ByteBuffer.allocate()
• [OrphanedFormatString] String literal contains format specifiers, but is not passed to a format method
• [ScopeOnModule] Scopes on modules have no function and will soon be an error
• [CatchAndPrintStackTrace] Logging or rethrowing exceptions should usually be preferred to catching and calling printStackTrace
• [VarTypeName] var should not be used as a type name

Other changes:

• Remove MoreAsserts from TryFailThrowable
• Add java.util.Arrays to ReturnValueIgnored check
• Improve BugCheckerRefactoringTestHelper usability
• Extend SizeGreaterThanOrEqualsZero check to check proto repeated fields
• Disallow method references to @DonotCall methods
• Disallow Error Prone BugPattern names that includes spaces.
• Add an optional suffix comment to SuggestedFixes.addSuppressWarnings
• Allow @CompatibleWith to be used on varargs parameters.
• Make StreamResourceLeak a warning
• Recognize null test methods in java.util.Objects in nullness analysis
• Detect more cases of nested and ignored futures.
• Make the failure message in DiagnosticTestHelper easier to read.
• Enable QualifierOrScopeOnInjectMethod as a WARNING
• Consolidate NamedParameters and ParameterName

Fixes issues: #789, #893, #897, #899, #899, #904, #914, #921, #931, #942, #945, #954, #993

Error Prone 2.2.0

New errors:

• [ComparableType] A new check for detecting incompatibility of types between the type of a class implementing Comparable<T> and T.
• [ConditionalExpressionNumericPromotion] A conditional expression with numeric second and third operands of differing types may give surprising results.

New warnings:

• [CatchFail] detects tests that ignore exceptions and then call fail()
• [ModifyCollectionInEnhancedForLoop] detects collections modified within loops.
• [ThreadLocalUsage] ThreadLocals should be stored in static fields.

New optional checks:

• [StringSplit] detects String.split(String), which has surprising behaviour.
• [StringSplitter] refactors uses of String.split to Splitter.
• [TypeParameterNaming] enforces that type parameters are named according to the google style guide.
• [RandomCast] casting a random number in the range [0.0, 1.0) to an integer or long always results in 0.

Changes to existing checks

• ArrayEquals now detects misuse of android.support.v4.util.ObjectsCompat#equals.
• EqualsIncompatibleType now detects misuse of android.support.v4.util.ObjectsCompat#equals.
• SizeGreaterThanOrEqualsZero now detects misuse of common Android-specific collections.
• FilesLinesLeak was renamed to StreamResourceLeak, and now checks other methods in Files.
• FunctionalInterfaceClash is no longer enabled by default.
• JUnit4{SetUp,TearDown}NotRun will find methods that look like setup or teardown methods, but have a @Before or @After annotation that are not org.junit.Before or org.junit.After.
• SimpleDateFormatConstant now handles all DateFormats, and is renamed to DateFormatConstant
• Disable RestrictToEnforcer by default (fixes #812).
• EqualsIncompatibleType/PredicateIncompatibleType/CollectionIncompatible now explore type parameters to ensure their compatibility: Foo<A> is incompatible with Foo<B> if A and B are incompatible with each-other.

Other changes

• Update to javac 9+181-r4173-1 (fixes #781 and #784).
• Remove BugPattern.suppressibility and BugPattern.customSuppressionAnnotations: suppressionAnnotations should be used instead.