checker/tests/regex/GroupCounts.java

import java.util.regex.Matcher;
import java.util.regex.Pattern;
import org.checkerframework.checker.regex.qual.Regex;
import org.checkerframework.checker.regex.util.RegexUtil;

public class GroupCounts {
  void testGroupCount() {
    @Regex(0) String s1 = "abc";
    @Regex(1) String s2 = "(abc)";
    @Regex(2) String s3 = "()(abc)";
    @Regex(3) String s4 = "(abc())()";
    @Regex(4) String s5 = "((((abc))))";

    @Regex(0) String s7 = "(abc)";
    @Regex String s9 = "()()(())";
    @Regex(2) String s10 = "()()(())";
    @Regex(3) String s11 = "()()(())";

    // :: error: (assignment)
    @Regex(2) String s6 = "nonregex("; // error
    // :: error: (assignment)
    @Regex(1) String s8 = "abc"; // error
    // :: error: (assignment)
    @Regex(3) String s12 = "()()"; // error
    // :: error: (assignment)
    @Regex(4) String s13 = "(())()"; // error
  }

  void testPatternCompileGroupCount(@Regex String r, @Regex(3) String r3, @Regex(5) String r5) {
    @Regex(5) Pattern p1 = Pattern.compile(r5);
    @Regex Pattern p2 = Pattern.compile(r5);
    @Regex Pattern p3 = Pattern.compile(r);

    // :: error: (assignment)
    @Regex(6) Pattern p4 = Pattern.compile(r5); // error
    // :: error: (assignment)
    @Regex(6) Pattern p5 = Pattern.compile(r3); // error

    // Make sure Pattern.compile still works when passed an @UnknownRegex String
    // that's actually a regex, with the warning suppressed.
    @SuppressWarnings("regex:argument")
    Pattern p6 = Pattern.compile("(" + r + ")");
  }

  void testConcatenationGroupCount(@Regex String r, @Regex(3) String r3, @Regex(5) String r5) {
    @Regex(0) String s1 = r + r;
    @Regex(3) String s2 = r + r3;
    @Regex(8) String s3 = r3 + r5;

    // :: error: (assignment)
    @Regex(1) String s4 = r + r;
    // :: error: (assignment)
    @Regex(4) String s5 = r + r3;
    // :: error: (assignment)
    @Regex(9) String s6 = r3 + r5;
  }

  void testCompoundConcatenationWithGroups(
      @Regex String s0, @Regex(1) String s1, @Regex(3) String s3) {
    s0 += s0;
    @Regex String test0 = s0;
    // :: error: (assignment)
    @Regex(1) String test01 = s0;

    s0 += s1;
    @Regex(1) String test1 = s0;
    // :: error: (assignment)
    @Regex(2) String test12 = s0;

    s1 += s3;
    @Regex(4) String test4 = s1;
    // :: error: (assignment)
    @Regex(5) String test45 = s1;
  }

  void testAsRegexGroupCounts(String s) {
    @Regex String test1 = RegexUtil.asRegex(s);
    // :: error: (assignment)
    @Regex(1) String test2 = RegexUtil.asRegex(s);

    @Regex(3) String test3 = RegexUtil.asRegex(s, 3);
    // :: error: (assignment)
    @Regex(4) String test4 = RegexUtil.asRegex(s, 3);
  }

  void testMatcherGroupCounts(
      @Regex Matcher m0, @Regex(1) Matcher m1, @Regex(4) Matcher m4, int n) {
    m0.end(0);
    m0.group(0);
    m0.start(0);

    // :: error: (group.count)
    m0.end(1);
    // :: error: (group.count)
    m0.group(1);
    // :: error: (group.count)
    m0.start(1);

    m1.start(0);
    m1.start(1);

    // :: error: (group.count)
    m1.start(2);

    m4.start(0);
    m4.start(2);
    m4.start(4);

    // :: error: (group.count)
    m4.start(5);

    // :: warning: (group.count.unknown)
    m0.start(n);
  }
}