Bug in Intersects Operator when Comparing LineString/MultiLineString with MultiLineString

[jasonmfehr]

The following two queries return false in postgis, but when using the same inputs with com.esri.core.geometry.OperatorIntersects, it returns true. The issue seems to happen when the x values of the first LineString are all between the x-min and x-max of the envelope of the second MultiLineString and at least one y value of the first LineString is between the y-min and y-max of the envelope of the second MultiLineString.

select ST_Intersects(st_geomfromtext('LINESTRING(1 0, 1 1)'), st_geomfromtext('MULTILINESTRING((0 0, 0 1), (2 0, 2 1))'));
select st_intersects(st_geomfromtext('MULTILINESTRING((2 0, 2 2),(3 0, 3 2))'), st_geomfromtext('MULTILINESTRING((0 0, 0 2), (4 0, 4 2))'));

As a workaround, I compare each of the individual LineStrings from the first/second parameters with each other and return true if any of the individual compares return true, return false otherwise.

[jasonmfehr]

PoC JUnit test that fails because the intersects functions return true instead of false:

package org.example;

import static org.junit.jupiter.api.Assertions.assertFalse;

import com.esri.core.geometry.ogc.OGCGeometry;
import org.junit.jupiter.api.Test;

class GeometryIntersectsTest {

  @Test
  void intersectsLinestringAndMultilinestring() {
    OGCGeometry line = OGCGeometry.fromText("LINESTRING(1 0, 1 1)");
    OGCGeometry multiLine =
        OGCGeometry.fromText("MULTILINESTRING((0 0, 0 1), (2 0, 2 1))");

    assertFalse(line.intersects(multiLine));
    assertFalse(multiLine.intersects(line));
  }
}

[stolstov]

@jasonmfehr Thank you for the concise error report. This happens due to a typo in the disjoint test when envelopes of the polyline parts are tested before testing the segments.