MB-70026: Fixed error in polygon contains polylines

geojson/geojson_s2_util.go

@@ -136,44 +136,53 @@ func geometryCollectionIntersectsShape(gc *GeometryCollection,
 
 func polygonsContainsLineStrings(s2pgns []*s2.Polygon,
 	pls []*s2.Polyline) bool {
-	linesWithIn := make(map[int]struct{})
 	checker := s2.NewCrossingEdgeQuery(s2.NewShapeIndex())
-nextLine:
-	for lineIndex, pl := range pls {
+
+	// Every line segment in every linestring must be
+	// fully contained in atleast one of the polygons
+	for _, pl := range pls {
 		for i := 0; i < len(*pl)-1; i++ {
 			start := (*pl)[i]
 			end := (*pl)[i+1]
 
+			contains := false
 			for _, s2pgn := range s2pgns {
 				containsStart := s2pgn.ContainsPoint(start)
 				containsEnd := s2pgn.ContainsPoint(end)
+				// check if both end points are contained and if so,
+				// check if the line segment between them crosses the boundary of the polygon
 				if containsStart && containsEnd {
 					crossings := checker.Crossings(start, end, s2pgn, s2.CrossingTypeInterior)
 					if len(crossings) > 0 {
-						continue nextLine
+						continue
 					}
-					linesWithIn[lineIndex] = struct{}{}
-					continue nextLine
+					contains = true
+					break
 				} else {
+					// else we check if the line segment is an edge of the polygon
 					for _, loop := range s2pgn.Loops() {
 						for i := 0; i < loop.NumVertices(); i++ {
 							if !containsStart && start.ApproxEqual(loop.Vertex(i)) {
 								containsStart = true
-							} else if !containsEnd && end.ApproxEqual(loop.Vertex(i)) {
+							}
+							if !containsEnd && end.ApproxEqual(loop.Vertex(i)) {
 								containsEnd = true
 							}
 							if containsStart && containsEnd {
-								linesWithIn[lineIndex] = struct{}{}
-								continue nextLine
+								contains = true
+								break
 							}
 						}
 					}
 				}
 			}
+			if !contains {
+				return false
+			}
 		}
 	}
 
-	return len(pls) == len(linesWithIn)
+	return true
 }
 
 func rectangleIntersectsWithPolygons(s2rect *s2.Rect,

geojson/geojson_shapes_test.go

@@ -1300,7 +1300,7 @@ func TestPolygonContains(t *testing.T) {
 		},
 		{ // 6 - Linestring contained by polygon
 			query:  &Polygon{Typ: PolygonType, Vertices: [][][]float64{{{-1, 0}, {1, 0}, {2, 3}, {0, 3}, {-1, 0}}}},
-			other:  NewGeoJsonLinestring([][]float64{{2, 2}, {1, 1}, {0, 1}}),
+			other:  NewGeoJsonLinestring([][]float64{{1, 2}, {1, 1}, {0, 1}}),
 			output: true,
 		},
 		{ // 7 - Linestring with no intersection
@@ -1320,7 +1320,7 @@ func TestPolygonContains(t *testing.T) {
 		},
 		{ // 10 - Multilinestring with both linestrings contained by polygon
 			query:  &Polygon{Typ: PolygonType, Vertices: [][][]float64{{{-1, 0}, {1, 0}, {2, 3}, {0, 3}, {-1, 0}}}},
-			other:  NewGeoJsonMultilinestring([][][]float64{{{2, 2}, {1, 1}, {0, 1}}, {{0.5, 0.5}, {0, 1}, {0.5, 1.5}}}),
+			other:  NewGeoJsonMultilinestring([][][]float64{{{1, 2}, {1, 1}, {0, 1}}, {{0.5, 0.5}, {0, 1}, {0.5, 1.5}}}),
 			output: true,
 		},
 		{ // 11 - Multilinestring with no intersection
@@ -1465,7 +1465,7 @@ func TestMultiPolygonContains(t *testing.T) {
 		},
 		{ // 6 - Linestring contained by polygon
 			query:  &MultiPolygon{Typ: MultiPolygonType, Vertices: [][][][]float64{{{{100, 100}, {100, 101}, {101, 101}, {101, 100}, {100, 100}}}, {{{-1, 0}, {1, 0}, {2, 3}, {0, 3}, {-1, 0}}}}},
-			other:  NewGeoJsonLinestring([][]float64{{2, 2}, {1, 1}, {0, 1}}),
+			other:  NewGeoJsonLinestring([][]float64{{1, 2}, {1, 1}, {0, 1}}),
 			output: true,
 		},
 		{ // 7 - Linestring with no intersection
@@ -1485,7 +1485,7 @@ func TestMultiPolygonContains(t *testing.T) {
 		},
 		{ // 10 - Multilinestring with both linestrings contained by polygon
 			query:  &MultiPolygon{Typ: MultiPolygonType, Vertices: [][][][]float64{{{{100, 100}, {100, 101}, {101, 101}, {101, 100}, {100, 100}}}, {{{-1, 0}, {1, 0}, {2, 3}, {0, 3}, {-1, 0}}}}},
-			other:  NewGeoJsonMultilinestring([][][]float64{{{2, 2}, {1, 1}, {0, 1}}, {{0.5, 0.5}, {0, 1}, {0.5, 1.5}}}),
+			other:  NewGeoJsonMultilinestring([][][]float64{{{1, 2}, {1, 1}, {0, 1}}, {{0.5, 0.5}, {0, 1}, {0.5, 1.5}}}),
 			output: true,
 		},
 		{ // 11 - Multilinestring with no intersection