NPE in UnsafeWildcard

[jinlintt]

We just upgraded to 2.18 today and got an NPE on the first line of the following snippet.

    persistentBean.setLabelName(
        translationContext.get(TranslatorContextKeyConstants.LABEL_GROUP, new TypeToken<>() {}));

Stack trace.

   error-prone version: 2.18.0
   BugPattern: UnsafeWildcard
   Stack Trace:
   java.lang.NullPointerException
	at com.google.errorprone.bugpatterns.nullness.UnsafeWildcard.matchMethodInvocation(UnsafeWildcard.java:168)
	at com.google.errorprone.scanner.ErrorProneScanner.processMatchers(ErrorProneScanner.java:449)
	at com.google.errorprone.scanner.ErrorProneScanner.visitMethodInvocation(ErrorProneScanner.java:746)
	at com.google.errorprone.scanner.ErrorProneScanner.visitMethodInvocation(ErrorProneScanner.java:150)
	at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCMethodInvocation.accept(JCTree.java:1650)
	at jdk.compiler/com.sun.source.util.TreePathScanner.scan(TreePathScanner.java:82)
	at com.google.errorprone.scanner.Scanner.scan(Scanner.java:74)
	at com.google.errorprone.scanner.Scanner.scan(Scanner.java:48)
	at jdk.compiler/com.sun.source.util.TreeScanner.visitExpressionStatement(TreeScanner.java:433)
	at com.google.errorprone.scanner.ErrorProneScanner.visitExpressionStatement(ErrorProneScanner.java:633)
	at com.google.errorprone.scanner.ErrorProneScanner.visitExpressionStatement(ErrorProneScanner.java:150)
	at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCExpressionStatement.accept(JCTree.java:1460)
	at jdk.compiler/com.sun.source.util.TreePathScanner.scan(TreePathScanner.java:82)
	at com.google.errorprone.scanner.Scanner.scan(Scanner.java:74)
	at com.google.errorprone.scanner.Scanner.scan(Scanner.java:48)
	at jdk.compiler/com.sun.source.util.TreeScanner.scanAndReduce(TreeScanner.java:90)
	at jdk.compiler/com.sun.source.util.TreeScanner.scan(TreeScanner.java:105)
	at jdk.compiler/com.sun.source.util.TreeScanner.visitBlock(TreeScanner.java:248)
	at com.google.errorprone.scanner.ErrorProneScanner.visitBlock(ErrorProneScanner.java:520)
	at com.google.errorprone.scanner.ErrorProneScanner.visitBlock(ErrorProneScanner.java:150)
	at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCBlock.accept(JCTree.java:1032)
	at jdk.compiler/com.sun.source.util.TreePathScanner.scan(TreePathScanner.java:82)
	at com.google.errorprone.scanner.Scanner.scan(Scanner.java:74)
	at com.google.errorprone.scanner.Scanner.scan(Scanner.java:48)
	at jdk.compiler/com.sun.source.util.TreeScanner.scanAndReduce(TreeScanner.java:90)
	at jdk.compiler/com.sun.source.util.TreeScanner.visitMethod(TreeScanner.java:206)
	at com.google.errorprone.scanner.ErrorProneScanner.visitMethod(ErrorProneScanner.java:740)
	at com.google.errorprone.scanner.ErrorProneScanner.visitMethod(ErrorProneScanner.java:150)
	at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCMethodDecl.accept(JCTree.java:898)
	at jdk.compiler/com.sun.source.util.TreePathScanner.scan(TreePathScanner.java:82)
	at com.google.errorprone.scanner.Scanner.scan(Scanner.java:74)
	at com.google.errorprone.scanner.Scanner.scan(Scanner.java:48)
	at jdk.compiler/com.sun.source.util.TreeScanner.scanAndReduce(TreeScanner.java:90)
	at jdk.compiler/com.sun.source.util.TreeScanner.scan(TreeScanner.java:105)
	at jdk.compiler/com.sun.source.util.TreeScanner.scanAndReduce(TreeScanner.java:113)
	at jdk.compiler/com.sun.source.util.TreeScanner.visitClass(TreeScanner.java:187)
	at com.google.errorprone.scanner.ErrorProneScanner.visitClass(ErrorProneScanner.java:548)
	at com.google.errorprone.scanner.ErrorProneScanner.visitClass(ErrorProneScanner.java:150)
	at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCClassDecl.accept(JCTree.java:808)
	at jdk.compiler/com.sun.source.util.TreePathScanner.scan(TreePathScanner.java:82)
	at com.google.errorprone.scanner.Scanner.scan(Scanner.java:74)
	at com.google.errorprone.scanner.Scanner.scan(Scanner.java:48)
	at jdk.compiler/com.sun.source.util.TreeScanner.scan(TreeScanner.java:105)
	at jdk.compiler/com.sun.source.util.TreeScanner.scanAndReduce(TreeScanner.java:113)
	at jdk.compiler/com.sun.source.util.TreeScanner.visitCompilationUnit(TreeScanner.java:144)
	at com.google.errorprone.scanner.ErrorProneScanner.visitCompilationUnit(ErrorProneScanner.java:560)
	at com.google.errorprone.scanner.ErrorProneScanner.visitCompilationUnit(ErrorProneScanner.java:150)
	at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCCompilationUnit.accept(JCTree.java:591)
	at jdk.compiler/com.sun.source.util.TreePathScanner.scan(TreePathScanner.java:56)
	at com.google.errorprone.scanner.Scanner.scan(Scanner.java:58)
	at com.google.errorprone.scanner.ErrorProneScannerTransformer.apply(ErrorProneScannerTransformer.java:43)
	at com.google.errorprone.ErrorProneAnalyzer.finished(ErrorProneAnalyzer.java:156)
	at jdk.compiler/com.sun.tools.javac.api.MultiTaskListener.finished(MultiTaskListener.java:132)
	at jdk.compiler/com.sun.tools.javac.main.JavaCompiler.flow(JavaCompiler.java:1418)
	at jdk.compiler/com.sun.tools.javac.main.JavaCompiler.flow(JavaCompiler.java:1365)
	at jdk.compiler/com.sun.tools.javac.main.JavaCompiler.compile(JavaCompiler.java:960)
	at jdk.compiler/com.sun.tools.javac.main.Main.compile(Main.java:311)
	at jdk.compiler/com.sun.tools.javac.main.Main.compile(Main.java:170)
	at jdk.compiler/com.sun.tools.javac.Main.compile(Main.java:57)
	at jdk.compiler/com.sun.tools.javac.Main.main(Main.java:43)

[jinlintt]

We worked around the problem by changing the code to the following

PersistentLabelName persistentLabelName =
        translationContext.get(TranslatorContextKeyConstants.LABEL_GROUP, new TypeToken<>() {});
persistentBean.setLabelName(persistentLabelName);