Merge pull request #890 from Turfjs/intersect-issue-820

Fixes #820 - `@turf/intersect`
Turfjs · Aug 11, 2017 · dd4d365 · dd4d365
2 parents f853637 + 3a30d12
commit dd4d365
Show file tree

Hide file tree

Showing 14 changed files with 219 additions and 77 deletions.
diff --git a/packages/turf-intersect/index.js b/packages/turf-intersect/index.js
@@ -1,5 +1,6 @@
 // depend on jsts for now http://bjornharrtell.github.io/jsts/
 var jsts = require('jsts');
+var truncate = require('@turf/truncate');
 
 /**
  * Takes two {@link Polygon|polygons} and finds their intersection. If they share a border, returns the border; if they don't intersect, returns undefined.
@@ -34,22 +35,21 @@ var jsts = require('jsts');
  * var addToMap = [poly1, poly2, intersection];
  */
 module.exports = function (poly1, poly2) {
-    var geom1, geom2;
-    if (poly1.type === 'Feature') geom1 = poly1.geometry;
-    else geom1 = poly1;
-    if (poly2.type === 'Feature') geom2 = poly2.geometry;
-    else geom2 = poly2;
+    var geom1 = (poly1.type === 'Feature') ? poly1.geometry : poly1;
+    var geom2 = (poly2.type === 'Feature') ? poly2.geometry : poly2;
+
     var reader = new jsts.io.GeoJSONReader();
-    var a = reader.read(JSON.stringify(geom1));
-    var b = reader.read(JSON.stringify(geom2));
+    var a = reader.read(truncate(geom1));
+    var b = reader.read(truncate(geom2));
     var intersection = a.intersection(b);
 
-    if (intersection.isEmpty()) {
-        return undefined;
-    }
+    if (intersection.isEmpty()) return {
+        type: 'Feature',
+        properties: {},
+        geometry: null
+    };
 
     var writer = new jsts.io.GeoJSONWriter();
-
     var geojsonGeometry = writer.write(intersection);
     return {
         type: 'Feature',

diff --git a/packages/turf-intersect/package.json b/packages/turf-intersect/package.json
@@ -34,6 +34,7 @@
     "write-json-file": "^2.0.0"
   },
   "dependencies": {
+    "@turf/truncate": "^4.6.0",
     "jsts": "1.3.0"
   }
 }
diff --git a/packages/turf-intersect/test.js b/packages/turf-intersect/test.js
@@ -23,10 +23,8 @@ test('intersect', t => {
         const features = geojson.features;
         const result = intersect(features[0], features[1]);
 
-        if (result) {
-            if (process.env.REGEN) write.sync(directories.out + filename, result);
-            t.deepEqual(result, load.sync(directories.out + filename), name);
-        }
+        if (process.env.REGEN) write.sync(directories.out + filename, result);
+        t.deepEqual(result, load.sync(directories.out + filename), name);
     }
     t.end();
 });
diff --git a/packages/turf-intersect/test/in/issue-820.geojson b/packages/turf-intersect/test/in/issue-820.geojson
@@ -0,0 +1,123 @@
+{
+  "type": "FeatureCollection",
+  "features": [
+    {
+      "type": "Feature",
+      "properties": {},
+      "geometry": {
+        "type": "Polygon",
+        "coordinates": [
+          [
+            [
+              43.741513133300735,
+              56.20222135938059
+            ],
+            [
+              43.74237144018551,
+              56.18856400988486
+            ],
+            [
+              43.77756202246089,
+              56.187608768581725
+            ],
+            [
+              43.77927863623042,
+              56.19639609165836
+            ],
+            [
+              43.763142466796836,
+              56.20212587032091
+            ],
+            [
+              43.741513133300735,
+              56.20222135938059
+            ]
+          ]
+        ]
+      }
+    },
+    {
+      "type": "Feature",
+      "properties": {},
+      "geometry": {
+        "type": "Polygon",
+        "coordinates": [
+          [
+            [
+              43.970066430113974,
+              56.332893840607994
+            ],
+            [
+              43.970066430115764,
+              56.33289386305967
+            ],
+            [
+              43.96907396330773,
+              56.33216050512385
+            ],
+            [
+              43.96712784882449,
+              56.3329676824026
+            ],
+            [
+              43.9675997442062,
+              56.33331243182769
+            ],
+            [
+              43.96955706305079,
+              56.33351088302814
+            ],
+            [
+              43.96958194836136,
+              56.33343379993835
+            ],
+            [
+              43.969613521760365,
+              56.3333626110674
+            ],
+            [
+              43.96964739754773,
+              56.3333044427381
+            ],
+            [
+              43.96968537953426,
+              56.3332457040905
+            ],
+            [
+              43.96973157401614,
+              56.333186395086614
+            ],
+            [
+              43.969791873109784,
+              56.333117882577056
+            ],
+            [
+              43.96983217547703,
+              56.3330786121781
+            ],
+            [
+              43.969883502771644,
+              56.3330312788475
+            ],
+            [
+              43.969928670817815,
+              56.332993640236595
+            ],
+            [
+              43.96997589197615,
+              56.33295771241299
+            ],
+            [
+              43.97002822123187,
+              56.332919492368774
+            ],
+            [
+              43.970066430113974,
+              56.332893840607994
+            ]
+          ]
+        ]
+      }
+    }
+  ]
+}
diff --git a/packages/turf-intersect/test/out/Intersect1.geojson b/packages/turf-intersect/test/out/Intersect1.geojson
@@ -6,40 +6,40 @@
 		"coordinates": [
 			[
 				[
-					-79.94623496447946,
-					32.89900638172028
+					-79.94623485028362,
+					32.89900648336843
 				],
 				[
-					-79.88571166992188,
-					32.887659962078956
+					-79.885712,
+					32.88766
 				],
 				[
-					-79.89395141601562,
-					32.75551989829049
+					-79.893951,
+					32.75552
 				],
 				[
-					-79.92322780260464,
-					32.73910022106017
+					-79.92322798892725,
+					32.739099979427955
 				],
 				[
-					-79.93789672851562,
-					32.74108223150125
+					-79.937897,
+					32.741082
 				],
 				[
-					-79.93034362792969,
-					32.76475877693074
+					-79.930344,
+					32.764759
 				],
 				[
-					-79.97360229492188,
-					32.76071688548088
+					-79.973602,
+					32.760717
 				],
 				[
-					-79.97428894042969,
-					32.83690450361482
+					-79.974289,
+					32.836905
 				],
 				[
-					-79.94623496447946,
-					32.89900638172028
+					-79.94623485028362,
+					32.89900648336843
 				]
 			]
 		]

diff --git a/packages/turf-intersect/test/out/Intersect2.geojson b/packages/turf-intersect/test/out/Intersect2.geojson
@@ -6,32 +6,32 @@
 		"coordinates": [
 			[
 				[
-					-80.0066252126598,
-					32.84617770697059
+					-80.00662505026214,
+					32.84617737765197
 				],
 				[
-					-80.01686096191406,
-					32.87266705436184
+					-80.016861,
+					32.872667
 				],
 				[
-					-80.068359375,
-					32.88189375925038
+					-80.068359,
+					32.881894
 				],
 				[
-					-80.0050160405751,
-					32.91295307720083
+					-80.0050161842375,
+					32.91295285230695
 				],
 				[
-					-79.98184204101562,
-					32.90495631913751
+					-79.981842,
+					32.904956
 				],
 				[
-					-79.99351501464844,
-					32.84440429734253
+					-79.993515,
+					32.844404
 				],
 				[
-					-80.0066252126598,
-					32.84617770697059
+					-80.00662505026214,
+					32.84617737765197
 				]
 			]
 		]

diff --git a/packages/turf-intersect/test/out/issue-412.geojson b/packages/turf-intersect/test/out/issue-412.geojson
@@ -6,28 +6,28 @@
 		"coordinates": [
 			[
 				[
-					11.076136797048882,
-					9.856269774244707
+					11.076137,
+					9.85627
 				],
 				[
-					11.1687361088318,
-					9.855073034114678
+					11.16873572210611,
+					9.855073127840765
 				],
 				[
-					11.167525294018606,
-					9.85386305739084
+					11.16752475470916,
+					9.853863
 				],
 				[
-					11.102599853580063,
-					9.85386305739084
+					11.102599666666666,
+					9.853863
 				],
 				[
-					11.076136797048884,
-					9.856269774244707
+					11.076138743097555,
+					9.856269454758179
 				],
 				[
-					11.076136797048882,
-					9.856269774244707
+					11.076137,
+					9.85627
 				]
 			]
 		]

diff --git a/packages/turf-intersect/test/out/issue-820.geojson b/packages/turf-intersect/test/out/issue-820.geojson
@@ -0,0 +1,5 @@
+{
+	"type": "Feature",
+	"properties": {},
+	"geometry": null
+}
diff --git a/packages/turf-intersect/test/out/linestring.geojson b/packages/turf-intersect/test/out/linestring.geojson
@@ -5,12 +5,12 @@
 		"type": "LineString",
 		"coordinates": [
 			[
-				4.86544132232666,
-				45.78434474634739
+				4.865441,
+				45.784345
 			],
 			[
-				4.88217830657959,
-				45.78745711798122
+				4.882178,
+				45.787457
 			]
 		]
 	}

diff --git a/packages/turf-intersect/test/out/multilinestring.geojson b/packages/turf-intersect/test/out/multilinestring.geojson
@@ -6,22 +6,22 @@
 		"coordinates": [
 			[
 				[
-					4.86544132232666,
-					45.78434474634739
+					4.865441,
+					45.784345
 				],
 				[
-					4.88217830657959,
-					45.78745711798122
+					4.882178,
+					45.787457
 				]
 			],
 			[
 				[
-					4.860033988952637,
-					45.78213006841216
+					4.860034,
+					45.78213
 				],
 				[
-					4.8618364334106445,
-					45.784404601286774
+					4.861836,
+					45.784405
 				]
 			]
 		]