transform-scale, transform-translate, transform-rotate: Invalidate stale bboxes after coordinate transforms

packages/turf-helpers/README.md

@@ -569,6 +569,18 @@ turf.isObject('foo')
 
 Returns **[boolean][23]** true/false, including false for Arrays and Functions
 
+## removeBbox
+
+Recursively removes bounding boxes from a GeoJSON object.
+
+This function mutates the input GeoJSON object.
+
+### Parameters
+
+*   `geojson` **[GeoJSON][24]** GeoJSON object whose bounding boxes should be removed
+
+Returns **void** 
+
 [1]: https://www.thoughtco.com/degree-of-latitude-and-longitude-distance-4070616
 
 [2]: #units
@@ -615,6 +627,8 @@ Returns **[boolean][23]** true/false, including false for Arrays and Functions
 
 [23]: https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Boolean
 
+[24]: https://tools.ietf.org/html/rfc7946#section-3
+
 <!-- 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. -->
 
 ---

packages/turf-helpers/index.ts

@@ -13,6 +13,7 @@ import {
   Polygon,
   Position,
   GeoJsonProperties,
+  GeoJSON,
 } from "geojson";
 
 import { Id } from "./lib/geojson.js";
@@ -877,6 +878,27 @@ export function isObject(input: any): boolean {
   return input !== null && typeof input === "object" && !Array.isArray(input);
 }
 
+/**
+ * Recursively removes bounding boxes from a GeoJSON object.
+ *
+ * This function mutates the input GeoJSON object.
+ *
+ * @function
+ * @param {GeoJSON} geojson GeoJSON object whose bounding boxes should be removed
+ * @returns {void}
+ */
+export function removeBbox(geojson: GeoJSON): void {
+  delete geojson.bbox;
+
+  if (geojson.type === "Feature") {
+    if (geojson.geometry) removeBbox(geojson.geometry);
+  } else if (geojson.type === "FeatureCollection") {
+    geojson.features.forEach(removeBbox);
+  } else if (geojson.type === "GeometryCollection") {
+    geojson.geometries.forEach(removeBbox);
+  }
+}
+
 /**
  * Validate BBox
  *

packages/turf-helpers/test.ts

@@ -22,6 +22,7 @@ import {
   isObject,
   isNumber,
   earthRadius,
+  removeBbox,
 } from "./index.js";
 import * as turf from "./index.js";
 
@@ -47,6 +48,38 @@ test("point", (t) => {
   t.end();
 });
 
+test("removeBbox", (t) => {
+  const line = lineString(
+    [
+      [0, 0],
+      [1, 1],
+    ],
+    { bbox: "property value is preserved" }
+  );
+  line.bbox = [0, 0, 1, 1];
+  line.geometry.bbox = [0, 0, 1, 1];
+
+  const collection = geometryCollection([line.geometry]);
+  collection.bbox = [0, 0, 1, 1];
+  collection.geometry.bbox = [0, 0, 1, 1];
+
+  const input = featureCollection([collection]);
+  input.bbox = [0, 0, 1, 1];
+
+  removeBbox(input);
+
+  t.notOk(input.bbox, "removes FeatureCollection bbox");
+  t.notOk(collection.bbox, "removes Feature bbox");
+  t.notOk(collection.geometry.bbox, "removes GeometryCollection bbox");
+  t.notOk(line.geometry.bbox, "removes nested geometry bbox");
+  t.equal(
+    line.properties.bbox,
+    "property value is preserved",
+    "does not alter feature properties"
+  );
+  t.end();
+});
+
 test("polygon", (t) => {
   const poly = polygon(
     [

packages/turf-helpers/types.ts

@@ -16,6 +16,7 @@ import {
   point,
   polygon,
   radiansToLength,
+  removeBbox,
 } from "./index.js";
 
 // Fixtures
@@ -58,6 +59,8 @@ const multiPoly = multiPolygon([
   ],
 ]);
 
+removeBbox(multiPoly);
+
 // radiansToLength & lengthToRadians
 radiansToLength(5);
 lengthToRadians(10);

packages/turf-transform-rotate/index.ts

@@ -6,7 +6,7 @@ import { rhumbDestination } from "@turf/rhumb-destination";
 import { clone } from "@turf/clone";
 import { coordEach } from "@turf/meta";
 import { getCoords } from "@turf/invariant";
-import { isObject, Coord } from "@turf/helpers";
+import { isObject, removeBbox, Coord } from "@turf/helpers";
 
 /**
  * Rotates any geojson Feature or Geometry of a specified angle, around its `centroid` or a given `pivot` point.
@@ -66,6 +66,7 @@ function transformRotate<T extends GeoJSON | GeometryCollection>(
     pointCoords[0] = newCoords[0];
     pointCoords[1] = newCoords[1];
   });
+  removeBbox(geojson);
   return geojson;
 }
 

packages/turf-transform-rotate/test.ts

@@ -147,3 +147,53 @@ function makePivot(pivot: Coord, geojson: GeoJSON | GeometryCollection) {
   }
   return point(getCoord(pivot), { "marker-symbol": "circle" });
 }
+
+test("rotate -- removes stale bbox values", (t) => {
+  const input = nestedGeojsonWithBboxes();
+  const rotated = rotate(input, 45);
+
+  t.equal(countBboxes(rotated), 0, "removes bboxes from cloned output");
+  t.ok(countBboxes(input) > 0, "does not alter input by default");
+
+  rotate(input, 45, { mutate: true });
+  t.equal(countBboxes(input), 0, "removes bboxes from mutated input");
+  t.end();
+});
+
+function nestedGeojsonWithBboxes() {
+  const geojson = featureCollection([
+    geometryCollection([
+      lineString([
+        [0, 0],
+        [1, 1],
+      ]).geometry,
+    ]),
+  ]);
+  addBboxes(geojson);
+  return geojson;
+}
+
+function addBboxes(geojson: GeoJSON | GeometryCollection): void {
+  geojson.bbox = [0, 0, 1, 1];
+  if (geojson.type === "Feature" && geojson.geometry) {
+    addBboxes(geojson.geometry);
+  } else if (geojson.type === "FeatureCollection") {
+    geojson.features.forEach(addBboxes);
+  } else if (geojson.type === "GeometryCollection") {
+    geojson.geometries.forEach(addBboxes);
+  }
+}
+
+function countBboxes(geojson: GeoJSON | GeometryCollection): number {
+  let count = geojson.bbox ? 1 : 0;
+  if (geojson.type === "Feature" && geojson.geometry) {
+    count += countBboxes(geojson.geometry);
+  } else if (geojson.type === "FeatureCollection") {
+    geojson.features.forEach((feature) => (count += countBboxes(feature)));
+  } else if (geojson.type === "GeometryCollection") {
+    geojson.geometries.forEach((geometry) => {
+      count += countBboxes(geometry);
+    });
+  }
+  return count;
+}

packages/turf-transform-scale/index.ts

@@ -1,4 +1,4 @@
-import { Corners, Coord } from "@turf/helpers";
+import { Corners, Coord, removeBbox } from "@turf/helpers";
 import { FeatureCollection, GeoJSON, GeometryCollection } from "geojson";
 import { clone } from "@turf/clone";
 import { center } from "@turf/center";
@@ -67,6 +67,7 @@ function transformScale<T extends GeoJSON | GeometryCollection>(
         origin
       );
     });
+    if (factor !== 1) delete geojson.bbox;
     return geojson;
   }
   // Scale Feature/Geometry
@@ -108,7 +109,7 @@ function scale<T extends GeoJSON | GeometryCollection>(
     if (coord.length === 3) coord[2] *= factor;
   });
 
-  delete feature.bbox;
+  removeBbox(feature);
 
   return feature;
 }

packages/turf-transform-scale/test.ts

@@ -1,4 +1,10 @@
-import { BBox, Feature, FeatureCollection } from "geojson";
+import {
+  BBox,
+  Feature,
+  FeatureCollection,
+  GeoJSON,
+  GeometryCollection,
+} from "geojson";
 import fs from "fs";
 import test from "tape";
 import path from "path";
@@ -277,6 +283,56 @@ function colorize(geojson: FeatureCollection | Feature) {
   return geojson;
 }
 
+test("scale -- removes stale bbox values", (t) => {
+  const input = nestedGeojsonWithBboxes();
+  const scaled = scale(input, 2, { origin: [0, 0] });
+
+  t.equal(countBboxes(scaled), 0, "removes bboxes from cloned output");
+  t.ok(countBboxes(input) > 0, "does not alter input by default");
+
+  scale(input, 2, { origin: [0, 0], mutate: true });
+  t.equal(countBboxes(input), 0, "removes bboxes from mutated input");
+  t.end();
+});
+
+function nestedGeojsonWithBboxes() {
+  const geojson = featureCollection([
+    geometryCollection([
+      lineString([
+        [0, 0],
+        [1, 1],
+      ]).geometry,
+    ]),
+  ]);
+  addBboxes(geojson);
+  return geojson;
+}
+
+function addBboxes(geojson: GeoJSON | GeometryCollection): void {
+  geojson.bbox = [0, 0, 1, 1];
+  if (geojson.type === "Feature" && geojson.geometry) {
+    addBboxes(geojson.geometry);
+  } else if (geojson.type === "FeatureCollection") {
+    geojson.features.forEach(addBboxes);
+  } else if (geojson.type === "GeometryCollection") {
+    geojson.geometries.forEach(addBboxes);
+  }
+}
+
+function countBboxes(geojson: GeoJSON | GeometryCollection): number {
+  let count = geojson.bbox ? 1 : 0;
+  if (geojson.type === "Feature" && geojson.geometry) {
+    count += countBboxes(geojson.geometry);
+  } else if (geojson.type === "FeatureCollection") {
+    geojson.features.forEach((feature) => (count += countBboxes(feature)));
+  } else if (geojson.type === "GeometryCollection") {
+    geojson.geometries.forEach((geometry) => {
+      count += countBboxes(geometry);
+    });
+  }
+  return count;
+}
+
 // define origin, as defined in transform-scale, and style it
 function markedOrigin(
   geojson: Feature,

packages/turf-transform-translate/index.ts

@@ -1,6 +1,6 @@
 import { GeoJSON, GeometryCollection } from "geojson";
 import { coordEach } from "@turf/meta";
-import { isObject, Units } from "@turf/helpers";
+import { isObject, removeBbox, Units } from "@turf/helpers";
 import { getCoords } from "@turf/invariant";
 import { clone } from "@turf/clone";
 import { rhumbDestination } from "@turf/rhumb-destination";
@@ -79,6 +79,7 @@ function transformTranslate<T extends GeoJSON | GeometryCollection>(
     if (zTranslation && pointCoords.length === 3)
       pointCoords[2] += zTranslation;
   });
+  removeBbox(geojson);
   return geojson;
 }
 

packages/turf-transform-translate/test.ts

@@ -1,4 +1,4 @@
-import { Feature } from "geojson";
+import { Feature, GeoJSON, GeometryCollection } from "geojson";
 import fs from "fs";
 import test from "tape";
 import path from "path";
@@ -152,3 +152,53 @@ function colorize(geojson: Feature) {
   }
   return geojson;
 }
+
+test("translate -- removes stale bbox values", (t) => {
+  const input = nestedGeojsonWithBboxes();
+  const translated = translate(input, 10, 45);
+
+  t.equal(countBboxes(translated), 0, "removes bboxes from cloned output");
+  t.ok(countBboxes(input) > 0, "does not alter input by default");
+
+  translate(input, 10, 45, { mutate: true });
+  t.equal(countBboxes(input), 0, "removes bboxes from mutated input");
+  t.end();
+});
+
+function nestedGeojsonWithBboxes() {
+  const geojson = featureCollection([
+    geometryCollection([
+      lineString([
+        [0, 0],
+        [1, 1],
+      ]).geometry,
+    ]),
+  ]);
+  addBboxes(geojson);
+  return geojson;
+}
+
+function addBboxes(geojson: GeoJSON | GeometryCollection): void {
+  geojson.bbox = [0, 0, 1, 1];
+  if (geojson.type === "Feature" && geojson.geometry) {
+    addBboxes(geojson.geometry);
+  } else if (geojson.type === "FeatureCollection") {
+    geojson.features.forEach(addBboxes);
+  } else if (geojson.type === "GeometryCollection") {
+    geojson.geometries.forEach(addBboxes);
+  }
+}
+
+function countBboxes(geojson: GeoJSON | GeometryCollection): number {
+  let count = geojson.bbox ? 1 : 0;
+  if (geojson.type === "Feature" && geojson.geometry) {
+    count += countBboxes(geojson.geometry);
+  } else if (geojson.type === "FeatureCollection") {
+    geojson.features.forEach((feature) => (count += countBboxes(feature)));
+  } else if (geojson.type === "GeometryCollection") {
+    geojson.geometries.forEach((geometry) => {
+      count += countBboxes(geometry);
+    });
+  }
+  return count;
+}