Use flattenEach with @turf/flatten

Turfjs · May 8, 2017 · e798e07 · e798e07
1 parent b49ce34
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diff --git a/packages/turf-flatten/README.md b/packages/turf-flatten/README.md
@@ -6,12 +6,12 @@ Flattens any [GeoJSON](GeoJSON) to a [FeatureCollection](http://geojson.org/geoj
 
 **Parameters**
 
--   `geojson` **[Feature](http://geojson.org/geojson-spec.html#feature-objects)** any valid [GeoJSON](GeoJSON) with multi-geometry [Feature](http://geojson.org/geojson-spec.html#feature-objects)s
+-   `geojson` **([FeatureCollection](http://geojson.org/geojson-spec.html#feature-collection-objects) \| [Geometry](http://geojson.org/geojson-spec.html#geometry) \| [Feature](http://geojson.org/geojson-spec.html#feature-objects)&lt;any>)** any valid GeoJSON Object
 
 **Examples**
 
 ```javascript
-var geometry = {
+var multiGeometry = {
   "type": "MultiPolygon",
   "coordinates": [
      [[[102.0, 2.0], [103.0, 2.0], [103.0, 3.0], [102.0, 3.0], [102.0, 2.0]]],
@@ -20,13 +20,13 @@ var geometry = {
    ]
  };
 
-var flatten = turf.flatten(geometry);
+var flatten = turf.flatten(multiGeometry);
 
 //addToMap
 var addToMap = [flatten]
 ```
 
-Returns **[FeatureCollection](http://geojson.org/geojson-spec.html#feature-collection-objects)** a flattened [FeatureCollection](http://geojson.org/geojson-spec.html#feature-collection-objects)
+Returns **[FeatureCollection](http://geojson.org/geojson-spec.html#feature-collection-objects)&lt;any>** all Multi-Geometries are flattened into single Features
 
 <!-- This file is automatically generated. Please don't edit it directly:
 if you find an error, edit the source file (likely index.js), and re-run

diff --git a/packages/turf-flatten/index.js b/packages/turf-flatten/index.js
@@ -1,20 +1,14 @@
-var featureEach = require('@turf/meta').featureEach;
-var geomEach = require('@turf/meta').geomEach;
-var getCoords = require('@turf/invariant').getCoords;
-var helpers = require('@turf/helpers');
-var point = helpers.point;
-var lineString = helpers.lineString;
-var polygon = helpers.polygon;
-var featureCollection = helpers.featureCollection;
+var flattenEach = require('@turf/meta').flattenEach;
+var featureCollection = require('@turf/helpers').featureCollection;
 
 /**
  * Flattens any {@link GeoJSON} to a {@link FeatureCollection} inspired by [geojson-flatten](https://github.com/tmcw/geojson-flatten).
  *
  * @name flatten
- * @param {Feature} geojson any valid {@link GeoJSON} with multi-geometry {@link Feature}s
- * @returns {FeatureCollection} a flattened {@link FeatureCollection}
+ * @param {FeatureCollection|Geometry|Feature<any>} geojson any valid GeoJSON Object
+ * @returns {FeatureCollection<any>} all Multi-Geometries are flattened into single Features
  * @example
- * var geometry = {
+ * var multiGeometry = {
  *   "type": "MultiPolygon",
  *   "coordinates": [
  *      [[[102.0, 2.0], [103.0, 2.0], [103.0, 3.0], [102.0, 3.0], [102.0, 2.0]]],
@@ -23,129 +17,18 @@ var featureCollection = helpers.featureCollection;
  *    ]
  *  };
  *
- * var flatten = turf.flatten(geometry);
+ * var flatten = turf.flatten(multiGeometry);
  *
  * //addToMap
  * var addToMap = [flatten]
  */
 function flatten(geojson) {
-    var type = (geojson.geometry) ? geojson.geometry.type : geojson.type;
-    switch (type) {
-    case 'MultiPoint':
-        return flattenMultiPoint(geojson);
-    case 'MultiPolygon':
-        return flattenMultiPolygon(geojson);
-    case 'MultiLineString':
-        return flattenMultiLineString(geojson);
-    case 'FeatureCollection':
-        return flattenFeatureCollection(geojson);
-    case 'GeometryCollection':
-        return flattenGeometryCollection(geojson);
-    case 'Point':
-    case 'LineString':
-    case 'Polygon':
-        return featureCollection([geojson]);
-    }
-}
-module.exports = flatten;
-
-/**
- * Flatten MultiPoint
- *
- * @private
- * @param {Feature<MultiPoint>} geojson GeoJSON Feature
- * @returns {FeatureCollection<Point>} Feature Collection
- */
-function flattenMultiPoint(geojson) {
-    var points = [];
-    getCoords(geojson).forEach(function (coords) {
-        points.push(point(coords, geojson.properties));
-    });
-    return featureCollection(points);
-}
-
-/**
- * Flatten MultiLineString
- *
- * @private
- * @param {Feature<MultiLineString>} geojson GeoJSON Feature
- * @returns {FeatureCollection<LineString>} Feature Collection
- */
-function flattenMultiLineString(geojson) {
-    var lines = [];
-    getCoords(geojson).forEach(function (coords) {
-        lines.push(lineString(coords, geojson.properties));
-    });
-    return featureCollection(lines);
-}
-
-/**
- * Flatten MultiPolygon
- *
- * @private
- * @param {Feature<MultiPolygon>} geojson GeoJSON Feature
- * @returns {FeatureCollection<Polygon>} Feature Collection
- */
-function flattenMultiPolygon(geojson) {
-    var polygons = [];
-    getCoords(geojson).forEach(function (coords) {
-        polygons.push(polygon(coords, geojson.properties));
-    });
-    return featureCollection(polygons);
-}
+    if (!geojson) throw new Error('geojson is required');
 
-/**
- * Flatten FeatureCollection
- *
- * @private
- * @param {FeatureCollection<any>} geojson GeoJSON Feature
- * @returns {FeatureCollection<any>} Feature Collection
- */
-function flattenFeatureCollection(geojson) {
-    var features = [];
-    featureEach(geojson, function (multiFeature) {
-        switch (multiFeature.geometry.type) {
-        case 'MultiPoint':
-        case 'MultiLineString':
-        case 'MultiPolygon':
-            featureEach(flatten(multiFeature), function (feature) {
-                features.push(feature);
-            });
-            break;
-        default:
-            features.push(multiFeature);
-        }
+    var results = [];
+    flattenEach(geojson, function (feature) {
+        results.push(feature);
     });
-    return featureCollection(features);
-}
-
-/**
- * Flatten GeometryCollection
- *
- * @private
- * @param {GeometryCollection<any>} geojson GeoJSON Geometry Collection
- * @param {*} [properties] translate properties to Feature
- * @returns {FeatureCollection<any>} Feature Collection
- */
-function flattenGeometryCollection(geojson) {
-    var features = [];
-    geomEach(geojson, function (geometry) {
-        switch (geometry.type) {
-        case 'MultiPoint':
-        case 'MultiLineString':
-        case 'MultiPolygon':
-            featureEach(flatten(geometry), function (feature) {
-                features.push(feature);
-            });
-            break;
-        default:
-            var feature = {
-                type: 'Feature',
-                properties: {},
-                geometry: geometry
-            };
-            features.push(feature);
-        }
-    });
-    return featureCollection(features);
+    return featureCollection(results);
 }
+module.exports = flatten;