Actually Polygons with empty coordinates arrays are fine, stick with …

…that.
Turfjs · Jan 22, 2025 · 0ff7cf7 · 0ff7cf7
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diff --git a/packages/turf-bbox-clip/README.md b/packages/turf-bbox-clip/README.md
@@ -4,14 +4,15 @@
 
 ## bboxClip
 
-Takes a [Feature][1] and a bbox and clips the feature to the bbox using
-[lineclip][2].
-May result in degenerate edges when clipping Polygons.
+Takes a [Feature][1], [Geometry][2] or [FeatureCollection][3] and a bbox and clips the object to the bbox using
+[lineclip][4].
+If a Point or LineString geometry is entirely outside the bbox, a [MultiPoint][5] or [MultiLineString][6] with empty `coordinates` array is returned.
+LineString and Polygon geometries may also become MultiLineString or [MultiPolygon][7] if the clipping process cuts them into several pieces.
 
 ### Parameters
 
-*   `feature` **[Feature][1]<([LineString][3] | [MultiLineString][4] | [Polygon][5] | [MultiPolygon][6])>** feature to clip to the bbox
-*   `bbox` **[BBox][7]** extent in \[minX, minY, maxX, maxY] order
+*   `feature` **[Feature][1]<([Point][8] | [MultiPoint][5] | [LineString][9] | [MultiLineString][6] | [Polygon][10] | [MultiPolygon][7])>** feature to clip to the bbox
+*   `bbox` **[BBox][11]** extent in \[minX, minY, maxX, maxY] order
 
 ### Examples
 
@@ -25,21 +26,29 @@ var clipped = turf.bboxClip(poly, bbox);
 var addToMap = [bbox, poly, clipped]
 ```
 
-Returns **[Feature][1]<([LineString][3] | [MultiLineString][4] | [Polygon][5] | [MultiPolygon][6])>** clipped Feature
+Returns **[Feature][1]<([Point][8] | [MultiPoint][5] | [LineString][9] | [MultiLineString][6] | [Polygon][10] | [MultiPolygon][7])>** clipped Feature
 
 [1]: https://tools.ietf.org/html/rfc7946#section-3.2
 
-[2]: https://github.com/mapbox/lineclip
+[2]: https://tools.ietf.org/html/rfc7946#section-3.1
 
-[3]: https://tools.ietf.org/html/rfc7946#section-3.1.4
+[3]: https://tools.ietf.org/html/rfc7946#section-3.3
 
-[4]: https://tools.ietf.org/html/rfc7946#section-3.1.5
+[4]: https://github.com/mapbox/lineclip
 
-[5]: https://tools.ietf.org/html/rfc7946#section-3.1.6
+[5]: https://tools.ietf.org/html/rfc7946#section-3.1.3
 
-[6]: https://tools.ietf.org/html/rfc7946#section-3.1.7
+[6]: https://tools.ietf.org/html/rfc7946#section-3.1.5
 
-[7]: https://tools.ietf.org/html/rfc7946#section-5
+[7]: https://tools.ietf.org/html/rfc7946#section-3.1.7
+
+[8]: https://tools.ietf.org/html/rfc7946#section-3.1.2
+
+[9]: https://tools.ietf.org/html/rfc7946#section-3.1.4
+
+[10]: https://tools.ietf.org/html/rfc7946#section-3.1.6
+
+[11]: https://tools.ietf.org/html/rfc7946#section-5
 
 <!-- This file is automatically generated. Please don't edit it directly. If you find an error, edit the source file of the module in question (likely index.js or index.ts), and re-run "yarn docs" from the root of the turf project. -->
 

diff --git a/packages/turf-bbox-clip/index.ts b/packages/turf-bbox-clip/index.ts
@@ -30,8 +30,8 @@ import { lineclip, polygonclip } from "./lib/lineclip.js";
 /**
  * Takes a {@link Feature}, {@link Geometry} or {@link FeatureCollection} and a bbox and clips the object to the bbox using
  * [lineclip](https://github.com/mapbox/lineclip).
- * If a geometry is entirely outside the bbox, a Multi-geometry with no coordinates is returned.
- * LineString and Polygon geometries may also become Multi-geometry if the clipping process cuts them into several pieces.
+ * If a Point or LineString geometry is entirely outside the bbox, a {@link MultiPoint} or {@link MultiLineString} with empty `coordinates` array is returned.
+ * LineString and Polygon geometries may also become MultiLineString or {@link MultiPolygon} if the clipping process cuts them into several pieces.
  *
  * @function
  * @param {Feature<Point|MultiPoint|LineString|MultiLineString|Polygon|MultiPolygon>} feature feature to clip to the bbox
@@ -62,7 +62,6 @@ function bboxClip<
   G extends Polygon | MultiPolygon,
   P extends GeoJsonProperties = GeoJsonProperties,
 >(feature: Feature<G, P> | G, bbox: BBox): Feature<Polygon | MultiPolygon, P>;
-
 function bboxClip<
   G extends GeometryCollection,
   P extends GeoJsonProperties = GeoJsonProperties,
@@ -120,18 +119,14 @@ function bboxClip<
       coords.forEach((line) => {
         lineclip(line, bbox, lines);
       });
-      if (lines.length === 1) {
+      if (lines.length === 1 && type === "LineString") {
         return lineString(lines[0], properties);
       }
       return multiLineString(lines, properties);
     }
     case "Polygon": {
       const poly = clipPolygon(coords, bbox);
-      if (poly.length === 0) {
-        return multiPolygon([], properties);
-      } else {
-        return polygon(poly, properties);
-      }
+      return polygon(poly, properties);
     }
     case "MultiPolygon":
       return multiPolygon(

diff --git a/packages/turf-bbox-clip/test/out/feature-collection.geojson b/packages/turf-bbox-clip/test/out/feature-collection.geojson
@@ -188,7 +188,7 @@
         "fill-opacity": 0.1
       },
       "geometry": {
-        "type": "MultiPolygon",
+        "type": "Polygon",
         "coordinates": []
       }
     },

diff --git a/packages/turf-bbox-clip/test/out/geometry-collection.geojson b/packages/turf-bbox-clip/test/out/geometry-collection.geojson
@@ -106,7 +106,7 @@
             "coordinates": []
           },
           {
-            "type": "MultiPolygon",
+            "type": "Polygon",
             "coordinates": []
           }
         ]

diff --git a/packages/turf-bbox-clip/test/out/polygon-outside.geojson b/packages/turf-bbox-clip/test/out/polygon-outside.geojson
@@ -31,7 +31,7 @@
         "fill-opacity": 0.1
       },
       "geometry": {
-        "type": "MultiPolygon",
+        "type": "Polygon",
         "coordinates": []
       }
     },

diff --git a/packages/turf-bbox-clip/test/out/polygon-point-intersection.geojson b/packages/turf-bbox-clip/test/out/polygon-point-intersection.geojson
@@ -35,7 +35,7 @@
         "fill-opacity": 0.1
       },
       "geometry": {
-        "type": "MultiPolygon",
+        "type": "Polygon",
         "coordinates": []
       }
     },