Turf polygonize

packages/turf-polygonize/LICENSE

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+The MIT License (MIT)
+
+Copyright (c) 2017 TurfJS
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software is furnished to do so,
+subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

packages/turf-polygonize/README.md

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+# @turf/polygonize
+
+# index
+
+Implementation of GEOSPolygonize function (`geos::operation::polygonize::Polygonizer`).
+
+Polygonizes a set of lines that represents edges in a planar graph. Edges must be correctly
+noded, i.e., they must only meet at their endpoints. LineStrings must only have two coordinate
+points.
+
+The implementation correctly handles:
+
+-   Dangles: edges which have one or both ends which are not incident on another edge endpoint.
+-   Cut Edges (bridges): edges that are connected at both ends but which do not form part
+      of a polygon.
+
+**Parameters**
+
+-   `geoJson` **[FeatureCollection](http://geojson.org/geojson-spec.html#feature-collection-objects)<[LineString](http://geojson.org/geojson-spec.html#linestring)>** Lines in order to polygonize
+
+Returns **[FeatureCollection](http://geojson.org/geojson-spec.html#feature-collection-objects)<[Polygon](http://geojson.org/geojson-spec.html#polygon)>** Polygons created
+
+<!-- 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
+./scripts/generate-readmes in the turf project. -->
+
+---
+
+This module is part of the [Turfjs project](http://turfjs.org/), an open source
+module collection dedicated to geographic algorithms. It is maintained in the
+[Turfjs/turf](https://github.com/Turfjs/turf) repository, where you can create
+PRs and issues.
+
+### Installation
+
+Install this module individually:
+
+```sh
+$ npm install @turf/polygonize
+```
+
+Or install the Turf module that includes it as a function:
+
+```sh
+$ npm install @turf/turf
+```

packages/turf-polygonize/index.js

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+var polygonize = require('polygonize');
+
+/** Implementation of GEOSPolygonize function (`geos::operation::polygonize::Polygonizer`).
+ *
+ * Polygonizes a set of lines that represents edges in a planar graph. Edges must be correctly
+ * noded, i.e., they must only meet at their endpoints. LineStrings must only have two coordinate
+ * points.
+ *
+ * The implementation correctly handles:
+ *
+ * - Dangles: edges which have one or both ends which are not incident on another edge endpoint.
+ * - Cut Edges (bridges): edges that are connected at both ends but which do not form part
+ *     of a polygon.
+ *
+ * @param {FeatureCollection<LineString>} geoJson - Lines in order to polygonize
+ * @returns {FeatureCollection<Polygon>} - Polygons created
+ */
+module.exports = polygonize;

packages/turf-polygonize/package.json

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+{
+  "name": "@turf/polygonize",
+  "version": "4.3.0",
+  "description": "turf polygonize module",
+  "main": "index.js",
+  "files": [
+    "index.js"
+  ],
+  "scripts": {
+    "test": "tape test.js"
+  },
+  "repository": {
+    "type": "git",
+    "url": "git://github.com/Turfjs/turf.git"
+  },
+  "keywords": [
+    "turf",
+    "geojson",
+    "gis",
+    "polygonize"
+  ],
+  "author": "Turf Authors",
+  "contributors": [
+    "Nicolas Cisco <@nickcis>"
+  ],
+  "license": "MIT",
+  "bugs": {
+    "url": "https://github.com/Turfjs/turf/issues"
+  },
+  "homepage": "https://github.com/Turfjs/turf#readme",
+  "devDependencies": {
+    "@turf/helpers": "^4.3.0",
+    "tape": "^4.6.3"
+  },
+  "dependencies": {
+    "polygonize": "^1.0.0"
+  }
+}

packages/turf-polygonize/test.js

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+const test = require('tape'),
+  { featureCollection, lineString, polygon } = require('@turf/helpers'),
+  polygonize = require('./'),
+  fs = require('fs'),
+  path = require('path');
+
+const directories = {
+  in: path.join(__dirname, 'test', 'in') + path.sep,
+  out: path.join(__dirname, 'test', 'out') + path.sep,
+};
+
+function getFullPath(filename, type='in') {
+  return path.join(directories[type], filename);
+}
+
+function readJsonFile(filename, type='in') {
+  try {
+    return JSON.parse(fs.readFileSync(getFullPath(filename, type)));
+  } catch(e) {
+    if (e.code !== 'ENOENT')
+      throw e;
+    return undefined;
+  }
+}
+
+function writeJsonFile(filename, data, type='out') {
+  fs.writeFileSync(getFullPath(filename, type), JSON.stringify(data));
+}
+
+fs.readdirSync(directories.in)
+  .filter(filename => !filename.startsWith('.'))
+  .map(filename => {
+    return {
+      filename,
+      name: path.parse(filename).name,
+      input: readJsonFile(filename, 'in'),
+      output: readJsonFile(filename, 'out'),
+    }
+  })
+  .forEach(({filename, name, input, output}) => {
+    test(`turf-polygonize :: ${name}`, t => {
+      const result = polygonize(input);
+      if (output) {
+        t.deepEqual(result, output);
+      } else {
+        t.skip(`${name} not found :: writing`);
+        writeJsonFile(filename, result);
+      }
+      t.end();
+    });
+  });