UnnecessarySemicolonRule throws exceptions for Groovy 3

[dmurat]

I'm trying to run the latest CodeNarc from master on a Groovy 3 project (an exact groovy version is 3.0.4). However, UneccessarySemicoloRule throws IndexOutOfBoundException on line 69. After changing the checkLastLineForSemicolon method as shown below, everything started to work correctly.

private void checkLastLineForSemicolon(SourceCode sourceCode, List<Violation> violations, AnnotatedNode node) {
    int lineNumber = node.getLastLineNumber()
    if (lineNumber < 1) { // <--- check added
        return
    }

    String line = sourceCode.getLines().get(lineNumber - 1) + ' '   // to make it easier to extract the final chars
    int lastColumn = node.lastColumnNumber
    boolean lastCharIsSemicolon = line[lastColumn - 1] == ';'

    if (lastCharIsSemicolon) {
        violations << createViolation(lineNumber, line, MESSAGE)
    }
}

Tnx

[dmurat]

I believe the root cause is in Groovy - https://issues.apache.org/jira/browse/GROOVY-9577
I'm not sure if it makes sense fixing it in CondeNarc. Probably not.

[chrismair]

Can you please provide some sample code that causes the above exception, so I can add a test for that.

[dmurat]

Sure, there is a test that triggered the problem for me:

@Test
void test_NoViolations_WithClassAnnotations() {
    final SOURCE = '''
        package foo
        
        import java.io.CharArrayReader
        import java.nio.file.AccessMode
        import java.io.Bits
        
        import java.lang.String

        class A {
            String firstName
            
            int a() {
                return 1
            }
        }
    '''

    assertNoViolations(SOURCE)
}

I added the test in UnnecessarySemicolonRuleTest and run it with following changes in build.gradle

def groovyTestVersion = '3.0.4'
...
dependencies {
  ...
  testRuntimeOnly("org.codehaus.groovy:groovy:$groovyTestVersion")
  testRuntimeOnly("org.codehaus.groovy:groovy-xml:$groovyTestVersion")
  testRuntimeOnly("org.codehaus.groovy:groovy-json:$groovyTestVersion")
  testRuntimeOnly("org.codehaus.groovy:groovy-ant:$groovyTestVersion")
  testRuntimeOnly("org.codehaus.groovy:groovy-templates:$groovyTestVersion")
}

Basically, whenever you add some package that Groovy does not include by default, the error can occur. If it passes, try adding more imports from "non-standard" packages.

[dmurat]

I just noticed that the name of a test is wrong. Previously I suspected that rule failed because of additional annotations on a class. But it turns out that imports are the problem.

[chrismair]

Thanks for providing the sample code and pointing out the fix!