com.google.errorprone.bugpatterns.time.DurationGetTemporalUnit Maven / Gradle / Ivy
/*
* Copyright 2018 The Error Prone Authors.
*
* 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.google.errorprone.bugpatterns.time;
import static com.google.errorprone.BugPattern.SeverityLevel.ERROR;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Iterables;
import com.google.errorprone.BugPattern;
import com.google.errorprone.VisitorState;
import com.google.errorprone.bugpatterns.BugChecker;
import com.google.errorprone.bugpatterns.BugChecker.MethodInvocationTreeMatcher;
import com.google.errorprone.fixes.SuggestedFix;
import com.google.errorprone.matchers.Description;
import com.google.errorprone.matchers.Matcher;
import com.google.errorprone.matchers.Matchers;
import com.google.errorprone.util.ASTHelpers;
import com.sun.source.tree.ExpressionTree;
import com.sun.source.tree.IdentifierTree;
import com.sun.source.tree.MemberSelectTree;
import com.sun.source.tree.MethodInvocationTree;
import java.time.temporal.ChronoUnit;
import java.util.EnumSet;
import java.util.Optional;
/**
* Bans calls to {@code Duration.get(temporalUnit)} where {@code temporalUnit} is not {@code
* SECONDS} or {@code NANOS}.
*/
@BugPattern(
summary = "Duration.get() only works with SECONDS or NANOS.",
explanation =
"`Duration.get(TemporalUnit)` only works when passed `ChronoUnit.SECONDS` or "
+ "`ChronoUnit.NANOS`. All other values are guaranteed to throw a "
+ "`UnsupportedTemporalTypeException`. In general, you should avoid "
+ "`duration.get(ChronoUnit)`. Instead, please use `duration.toNanos()`, "
+ "`Durations.toMicros(duration)`, `duration.toMillis()`, `duration.getSeconds()`, "
+ "`duration.toMinutes()`, `duration.toHours()`, or `duration.toDays()`.",
severity = ERROR)
public final class DurationGetTemporalUnit extends BugChecker
implements MethodInvocationTreeMatcher {
private static final ImmutableSet INVALID_TEMPORAL_UNITS =
ImmutableSet.copyOf(EnumSet.complementOf(EnumSet.of(ChronoUnit.SECONDS, ChronoUnit.NANOS)));
private static final ImmutableMap SUGGESTIONS =
ImmutableMap.builder()
.put(ChronoUnit.DAYS, ".toDays()")
.put(ChronoUnit.HOURS, ".toHours()")
.put(ChronoUnit.MINUTES, ".toMinutes()")
// SECONDS is omitted because it's a valid parameter
.put(ChronoUnit.MILLIS, ".toMillis()")
.buildOrThrow();
private static final Matcher MATCHER =
Matchers.instanceMethod()
.onExactClass("java.time.Duration")
.named("get")
.withParameters("java.time.temporal.TemporalUnit");
@Override
public Description matchMethodInvocation(MethodInvocationTree tree, VisitorState state) {
if (MATCHER.matches(tree, state)) {
Optional invalidUnit =
getInvalidChronoUnit(
Iterables.getOnlyElement(tree.getArguments()), INVALID_TEMPORAL_UNITS);
if (invalidUnit.isPresent()) {
if (SUGGESTIONS.containsKey(invalidUnit.get())) {
SuggestedFix.Builder builder = SuggestedFix.builder();
builder.replace(
tree,
state.getSourceForNode(ASTHelpers.getReceiver(tree))
+ SUGGESTIONS.get(invalidUnit.get()));
return describeMatch(tree, builder.build());
}
return describeMatch(tree);
}
}
return Description.NO_MATCH;
}
// used by PeriodGetTemporalUnit and DurationOfLongTemporalUnit
static Optional getInvalidChronoUnit(
ExpressionTree tree, Iterable invalidUnits) {
Optional constant = getEnumName(tree);
if (constant.isPresent()) {
for (ChronoUnit invalidTemporalUnit : invalidUnits) {
if (constant.get().equals(invalidTemporalUnit.name())) {
return Optional.of(invalidTemporalUnit);
}
}
}
return Optional.empty();
}
private static Optional getEnumName(ExpressionTree temporalUnit) {
if (temporalUnit instanceof IdentifierTree) { // e.g., SECONDS
return Optional.of(((IdentifierTree) temporalUnit).getName().toString());
}
if (temporalUnit instanceof MemberSelectTree) { // e.g., ChronoUnit.SECONDS
return Optional.of(((MemberSelectTree) temporalUnit).getIdentifier().toString());
}
return Optional.empty();
}
}