checker/jtreg/nullness/issue1929/Issue1929.java

/*
 * @test
 * @summary Test case for Issue 1929: test -Alint=trustArrayLenZero
 *
 * @compile/fail/ref=Issue1929-notrust.out -XDrawDiagnostics -processor org.checkerframework.checker.nullness.NullnessChecker Issue1929.java
 * @compile/fail/ref=Issue1929-trust.out -XDrawDiagnostics -processor org.checkerframework.checker.nullness.NullnessChecker -Alint=trustArrayLenZero Issue1929.java
 */

import java.util.Collection;
import org.checkerframework.common.value.qual.ArrayLen;

public class Issue1929 {

  String[] works1(Collection<String> c) {
    return c.toArray(new String[0]);
  }

  private static final String @ArrayLen(0) [] EMPTY_STRING_ARRAY_2 = new String[0];

  String[] fails2(Collection<String> c) {
    return c.toArray(EMPTY_STRING_ARRAY_2);
  }

  private static final String[] EMPTY_STRING_ARRAY_3 = new String[0];

  String[] fails3(Collection<String> c) {
    // We don't determine field types from initialization expressions.
    // :: error: (return)
    return c.toArray(EMPTY_STRING_ARRAY_3);
  }
}