added test cases for issue #852

packages/turf-line-split/index.js

@@ -37,18 +37,18 @@ module.exports = function (line, splitter) {
 
  // remove excessive decimals from splitter
  // to avoid possible approximation issues in rbush
- truncate(splitter, 6, 3, true);
+ var truncatedSplitter = truncate(splitter, 7);
 
  switch (splitterType) {
  case 'Point':
- return splitLineWithPoint(line, splitter);
+ return splitLineWithPoint(line, truncatedSplitter);
  case 'MultiPoint':
- return splitLineWithPoints(line, flatten(splitter));
+ return splitLineWithPoints(line, flatten(truncatedSplitter));
  case 'LineString':
  case 'MultiLineString':
  case 'Polygon':
  case 'MultiPolygon':
- return splitLineWithPoints(line, lineIntersect(line, splitter));
+ return splitLineWithPoints(line, lineIntersect(line, truncatedSplitter));
  default:
  throw new Error('<splitter> geometry type is not supported');
  }
@@ -99,7 +99,7 @@ function splitLineWithPoints(line, splitter) {
 }
 
 /**
- * Split LineString with MultiPoint
+ * Split LineString with Point
  *
  * @private
  * @param {Feature<LineString>} line LineString
@@ -109,6 +109,12 @@ function splitLineWithPoints(line, splitter) {
 function splitLineWithPoint(line, splitter) {
  var results = [];
 
+ // handle endpoints
+ var startPoint = getCoords(line)[0];
+ var endPoint = getCoords(line)[line.geometry.coordinates.length - 1];
+ if (pointsEquals(startPoint, getCoords(splitter)) ||
+ pointsEquals(endPoint, getCoords(splitter))) return featureCollection([line]);
+
  // Create spatial index
  var tree = rbush();
  var segments = lineSegment(line);
@@ -123,8 +129,8 @@ function splitLineWithPoint(line, splitter) {
  // RBush might return multiple lines - only process the closest line to splitter
  var closestSegment = findClosestFeature(splitter, search);
 
- // Initial value is the first point of the first segments (begining of line)
- var initialValue = [getCoords(segments.features[0])[0]];
+ // Initial value is the first point of the first segments (beginning of line)
+ var initialValue = [startPoint];
  var lastCoords = featureReduce(segments, function (previous, current, index) {
  var currentCoords = getCoords(current)[1];
  var splitterCoords = getCoords(splitter);
@@ -134,8 +140,7 @@ function splitLineWithPoint(line, splitter) {
  previous.push(splitterCoords);
  results.push(lineString(previous));
  // Don't duplicate splitter coordinate (Issue #688)
- if (splitterCoords[0] === currentCoords[0] &&
- splitterCoords[1] === currentCoords[1]) return [splitterCoords];
+ if (pointsEquals(splitterCoords, currentCoords)) return [splitterCoords];
  return [splitterCoords, currentCoords];
 
  // Keep iterating over coords until finished or intersection is found
@@ -151,6 +156,7 @@ function splitLineWithPoint(line, splitter) {
  return featureCollection(results);
 }
 
+
 /**
  * Find Closest Feature
  *
@@ -160,22 +166,31 @@ function splitLineWithPoint(line, splitter) {
  * @returns {Feature<LineString>} closest LineString
  */
 function findClosestFeature(point, lines) {
- // Filter to one segment that is the closest to the line
- var closestDistance;
- var closestFeature;
  if (!lines.features) throw new Error('<lines> must contain features');
+ // Filter to one segment that is the closest to the line
  if (lines.features.length === 1) return lines.features[0];
 
+ var closestFeature;
+ var closestDistance = Infinity;
  featureEach(lines, function (segment) {
  var pt = pointOnLine(segment, point);
  var dist = pt.properties.dist;
- if (closestDistance === undefined) {
- closestFeature = segment;
- closestDistance = dist;
- } else if (dist < closestDistance) {
+ if (dist < closestDistance) {
  closestFeature = segment;
  closestDistance = dist;
  }
  });
  return closestFeature;
 }
+
+/**
+ * Compares two points and returns if they are equals
+ *
+ * @private
+ * @param {Array<number>} pt1 point
+ * @param {Array<number>} pt2 point
+ * @returns {boolean} true if they are equals
+ */
+function pointsEquals(pt1, pt2) {
+ return pt1[0] === pt2[0] && pt1[1] === pt2[1];
+}

packages/turf-line-split/test.js

@@ -33,17 +33,18 @@ test('turf-line-split', t => {
  t.end();
 });
 
-test('turf-line-split - lines should only contain 2 vertices #688', t => {
- const pt = point([8, 50]);
+test('turf-line-split -- throws', t => {
+ const pt = point([9, 50]);
  const line = lineString([[7, 50], [8, 50], [9, 50]]);
- const [line1, line2] = lineSplit(line, pt).features;
 
- t.deepEqual(line1, lineString([[7, 50], [8, 50]]), 'line1 should have 2 vertices');
- t.deepEqual(line2, lineString([[8, 50], [9, 50]]), 'line2 should have 2 vertices');
+ t.throws(() => lineSplit(null, pt), '<geojson> is required');
+ t.throws(() => lineSplit(line, null), '<geojson> is required');
+ t.throws(() => lineSplit(pt, pt), '<line> must be LineString');
+ t.throws(() => lineSplit(line, featureCollection([pt, line])), '<splitter> cannot be a FeatureCollection');
  t.end();
 });
 
-test('turf-line-split - splitter exactly on end of line', t => {
+test('turf-line-split -- splitter exactly on end of line', t => {
  const pt = point([9, 50]);
  const line = lineString([[7, 50], [8, 50], [9, 50]]);
  const features = lineSplit(line, pt).features;
@@ -52,18 +53,40 @@ test('turf-line-split - splitter exactly on end of line', t => {
  t.end();
 });
 
-test('turf-line-split -- throws', t => {
- const pt = point([9, 50]);
+
+test('turf-line-split -- lines should only contain 2 vertices #688', t => {
+ const middlePoint = point([8, 50]);
  const line = lineString([[7, 50], [8, 50], [9, 50]]);
+ const [line1, line2] = lineSplit(line, middlePoint).features;
 
- t.throws(() => lineSplit(null, pt), '<geojson> is required');
- t.throws(() => lineSplit(line, null), '<geojson> is required');
- t.throws(() => lineSplit(pt, pt), '<line> must be LineString');
- t.throws(() => lineSplit(line, featureCollection([pt, line])), '<splitter> cannot be a FeatureCollection');
+ t.deepEqual(line1, lineString([[7, 50], [8, 50]]), 'line1 should have 2 vertices');
+ t.deepEqual(line2, lineString([[8, 50], [9, 50]]), 'line2 should have 2 vertices');
+ t.end();
+});
+
+test("turf-line-split -- precision issue #852", t => {
+ const line = lineString([[9.2202022, 49.1438226], [9.2199531, 49.1439048], [9.2196177, 49.1440264]]);
+ const startPoint = point([9.2202022, 49.1438226]);
+ const middlePoint = point([9.2199531, 49.1439048]);
+ const endPoint = point([9.2196177, 49.1440264]);
+ const [line1, line2] = lineSplit(line, middlePoint).features;
 
+ t.deepEqual(line1, lineString([[9.2202022, 49.1438226], [9.2199531, 49.1439048]]), 'middlePoint: line1 should have 2 vertices');
+ t.deepEqual(line2, lineString([[9.2199531, 49.1439048], [9.2196177, 49.1440264]]), 'middlePoint: line2 should have 2 vertices');
+ t.deepEqual(lineSplit(line, startPoint).features, [line], 'startPoint: should only contain 1 line of 3 vertices');
+ t.deepEqual(lineSplit(line, endPoint).features, [line], 'endPoint: should only contain 1 line of 3 vertices');
  t.end();
 });
 
+test('turf-line-split -- prevent input mutation', t => {
+ const line = lineString([[9.2202022, 49.1438226], [9.2199531, 49.1439048], [9.2196177, 49.1440264]]);
+ const lineBefore = JSON.parse(JSON.stringify(line));
+ lineSplit(line, point([9.2196177, 49.1440264]));
+
+ t.deepEqual(line, lineBefore, 'line should be the same');
+ t.end();
+})
+
 
 /**
  * Colorize FeatureCollection
@@ -75,7 +98,7 @@ function colorize(geojson) {
  const results = [];
  featureEach(geojson, (feature, index) => {
  const r = (index % 2 === 0) ? 'F' : '0';
- const g = (index % 2 === 0) ? '0' : '0';
+ const g = '0';
  const b = (index % 2 === 0) ? '0' : 'F';
  feature.properties = Object.assign({
  stroke: '#' + r + g + b,

packages/turf-line-split/test/out/issue-#852.geojson

@@ -15,12 +15,8 @@
  49.1438226
  ],
  [
- 9.2199531,
+ 9.2199532,
  49.1439048
- ],
- [
- 9.219953,
- 49.143905
  ]
  ]
  }
@@ -35,8 +31,12 @@
  "type": "LineString",
  "coordinates": [
  [
- 9.219953,
- 49.143905
+ 9.2199532,
+ 49.1439048
+ ],
+ [
+ 9.2199531,
+ 49.1439048
  ],
  [
  9.2196177,
@@ -72,8 +72,8 @@
  "geometry": {
  "type": "Point",
  "coordinates": [
- 9.219953,
- 49.143905
+ 9.219953175634146,
+ 49.14390480825327
  ]
  }
  }