Parser fails when it encounters a variable named `_`

[donalmurtagh]

Describe the bug
In JDK v22, a feature was added to the Java language that allows unused variables to be named _. When the java parser encounters such a variable, it fails

To Reproduce
Run the annotator under JDK v22 on a codebase that contains an unused variable named _. The following sections show the relevant dependency versions, configuration, etc.

build.gradle

Relevant sections of the build file are

plugins {
    id "net.ltgt.errorprone" version "4.0.1"
}

dependencies {
    implementation "org.jspecify:jspecify:1.0.0"
    annotationProcessor 'edu.ucr.cs.riple.annotator:annotator-scanner:1.3.14'
    annotationProcessor "com.uber.nullaway:nullaway:0.11.1"
    errorprone "com.google.errorprone:error_prone_core:2.30.0"
    errorproneJavac "com.google.errorprone:javac:9+181-r4173-1"
}

tasks.withType(JavaCompile).configureEach {
    options.errorprone {
        check("NullAway", CheckSeverity.ERROR)
        check("AnnotatorScanner", CheckSeverity.ERROR)
        option("NullAway:AnnotatedPackages", "com.myapp")
        option("NullAway:SerializeFixMetadata", "true")
        option("NullAway:FixSerializationConfigPath", "/Users/donal/tmp/annotator-output/nullaway.xml")
        option("AnnotatorScanner:ConfigPath", "/Users/donal/tmp/annotator-output/scanner.xml")
    }

    options.compilerArgs << "-Xmaxerrs"<< "100000"
    options.compilerArgs << "-Xmaxwarns" << "100000"
}

paths.tsv

A tab character separates the two paths.

/Users/donal/tmp/annotator-output/nullaway.xml	/Users/donal/tmp/annotator-output/scanner.xml

Annotator Command

java -jar ~/tmp/annotator-core-1.3.14.jar -d ~/tmp/annotator-output -i jakarta.annotation.PostConstruct -bc "cd ~/workspace/my-app && ./gradlew build -x test" -cn NULLAWAY -cp ~/tmp/paths.tsv -n org.jspecify.annotations.Nullable

Expected behavior
Annotator should run successfully

Stack trace

Exception in thread "main" com.github.javaparser.ParseProblemException: (line 51,col 38) '_' is a reserved keyword.

        at com.github.javaparser.JavaParserAdapter.handleResult(JavaParserAdapter.java:83)
        at com.github.javaparser.JavaParserAdapter.parse(JavaParserAdapter.java:99)
        at com.github.javaparser.StaticJavaParser.parse(StaticJavaParser.java:173)
        at edu.ucr.cs.riple.injector.Injector.parse(Injector.java:173)
        at edu.ucr.cs.riple.core.registries.field.FieldRegistry$1.build(FieldRegistry.java:115)
        at edu.ucr.cs.riple.core.registries.field.FieldRegistry$1.build(FieldRegistry.java:97)
        at edu.ucr.cs.riple.core.registries.Registry.populateContent(Registry.java:122)
        at edu.ucr.cs.riple.core.registries.Registry.lambda$new$0(Registry.java:91)
        at java.base/java.lang.Iterable.forEach(Iterable.java:75)
        at edu.ucr.cs.riple.core.registries.Registry.<init>(Registry.java:88)
        at edu.ucr.cs.riple.core.registries.field.FieldRegistry.<init>(FieldRegistry.java:82)
        at edu.ucr.cs.riple.core.module.ModuleInfo.<init>(ModuleInfo.java:91)
        at edu.ucr.cs.riple.core.module.ModuleInfo.<init>(ModuleInfo.java:73)
        at edu.ucr.cs.riple.core.Context.<init>(Context.java:78)
        at edu.ucr.cs.riple.core.Annotator.<init>(Annotator.java:63)
        at edu.ucr.cs.riple.core.Main.main(Main.java:45)

OS (please complete the following information):

• OS: MacOS X
• Version: openjdk version "22.0.1" 2024-04-16
• Annotator Version: 1.3.14 (latest)

[donalmurtagh]

I guess there's not much the annotator can do about this until the java parser supports unnamed variables

[nimakarimipour]

@donalmurtagh Thanks for reporting the issue! I wanted to let you know that I’m actively monitoring for a new javaparser release. Once a release supporting Java 22 features is available, I’ll update the Annotator accordingly and inform you.