From 2a67e8e457bcf07d9f07ab56ddf232d057c4c838 Mon Sep 17 00:00:00 2001
From: Kim Truong <47833996+khtruong@users.noreply.github.com>
Date: Tue, 9 Apr 2019 15:46:47 -0700
Subject: [PATCH] fix: Handle rendering a single point (#7256)

* fix: Handle rendering a single point

* fix: typo
---
 .../deckgl/layers/common_spec.jsx             | 63 ++++++++++++++++++-
 .../visualizations/deckgl/layers/common.jsx   | 42 ++++++++++++-
 2 files changed, 102 insertions(+), 3 deletions(-)

diff --git a/superset/assets/spec/javascripts/visualizations/deckgl/layers/common_spec.jsx b/superset/assets/spec/javascripts/visualizations/deckgl/layers/common_spec.jsx
index a2a6ef3f5..c82eeeea4 100644
--- a/superset/assets/spec/javascripts/visualizations/deckgl/layers/common_spec.jsx
+++ b/superset/assets/spec/javascripts/visualizations/deckgl/layers/common_spec.jsx
@@ -17,7 +17,7 @@
  * under the License.
  */
 import { max } from 'd3-array';
-import { getAggFunc } from '../../../../../src/visualizations/deckgl/layers/common';
+import { getAggFunc, getBounds } from '../../../../../src/visualizations/deckgl/layers/common';
 
 describe('deckgl layers common', () => {
   it('getAggFunc', () => {
@@ -46,4 +46,65 @@ describe('deckgl layers common', () => {
     expect(getAggFunc('p95', accessor)(arr)).toEqual(2.9);
     expect(getAggFunc('p99', accessor)(arr)).toEqual(2.98);
   });
+
+  describe('getBounds', () => {
+    it('should return valid bounds for multiple points', () => {
+      const points = [
+        [0, 20],
+        [5, 25],
+        [10, 15],
+      ];
+      expect(getBounds(points)).toEqual([
+        [0, 15],
+        [10, 25],
+      ]);
+    });
+    it('should return valid bounds for single latitude point', () => {
+      const points = [
+        [0, 0],
+        [5, 0],
+      ];
+      expect(getBounds(points)).toEqual([
+        [0, -0.25],
+        [5, 0.25],
+      ]);
+    });
+    it('should return valid bounds for single longitude point', () => {
+      const points = [
+        [0, 0],
+        [0, 5],
+      ];
+      expect(getBounds(points)).toEqual([
+        [-0.25, 0],
+        [0.25, 5],
+      ]);
+    });
+    it('should return valid bounds for single point', () => {
+      const points = [
+        [0, 0],
+      ];
+      expect(getBounds(points)).toEqual([
+        [-0.25, -0.25],
+        [0.25, 0.25],
+      ]);
+    });
+    it('should return valid bounds for point 90, 180', () => {
+      const points = [
+        [180, 90],
+      ];
+      expect(getBounds(points)).toEqual([
+        [179.75, 89.75],
+        [180, 90],
+      ]);
+    });
+    it('should return valid bounds for point -90, -180', () => {
+      const points = [
+        [-180, -90],
+      ];
+      expect(getBounds(points)).toEqual([
+        [-180, -90],
+        [-179.75, -89.75],
+      ]);
+    });
+  });
 });
diff --git a/superset/assets/src/visualizations/deckgl/layers/common.jsx b/superset/assets/src/visualizations/deckgl/layers/common.jsx
index 7adf3b789..aaee55361 100644
--- a/superset/assets/src/visualizations/deckgl/layers/common.jsx
+++ b/superset/assets/src/visualizations/deckgl/layers/common.jsx
@@ -20,12 +20,50 @@ import { fitBounds } from 'viewport-mercator-project';
 import * as d3array from 'd3-array';
 import sandboxedEval from '../../../modules/sandbox';
 
+const PADDING = 0.25;
+const GEO_BOUNDS = {
+  LAT_MIN: -90,
+  LAT_MAX: 90,
+  LNG_MIN: -180,
+  LNG_MAX: 180,
+};
+
+/**
+ * Get the latitude bounds if latitude is a single coordinate
+ * @param latExt Latitude range
+ */
+function getLatBoundsForSingleCoordinate(latExt) {
+  const latMin = latExt[0] - PADDING < GEO_BOUNDS.LAT_MIN
+    ? GEO_BOUNDS.LAT_MIN
+    : latExt[0] - PADDING;
+  const latMax = latExt[1] + PADDING > GEO_BOUNDS.LAT_MAX
+    ? GEO_BOUNDS.LAT_MAX
+    : latExt[1] + PADDING;
+  return [latMin, latMax];
+}
+
+/**
+ * Get the longitude bounds if longitude is a single coordinate
+ * @param lngExt Longitude range
+ */
+function getLngBoundsForSingleCoordinate(lngExt) {
+  const lngMin = lngExt[0] - PADDING < GEO_BOUNDS.LNG_MIN
+    ? GEO_BOUNDS.LNG_MIN
+    : lngExt[0] - PADDING;
+  const lngMax = lngExt[1] + PADDING > GEO_BOUNDS.LNG_MAX
+    ? GEO_BOUNDS.LNG_MAX
+    : lngExt[1] + PADDING;
+  return [lngMin, lngMax];
+}
+
 export function getBounds(points) {
   const latExt = d3array.extent(points, d => d[1]);
   const lngExt = d3array.extent(points, d => d[0]);
+  const latBounds = latExt[0] === latExt[1] ? getLatBoundsForSingleCoordinate(latExt) : latExt;
+  const lngBounds = lngExt[0] === lngExt[1] ? getLngBoundsForSingleCoordinate(lngExt) : lngExt;
   return [
-    [lngExt[0], latExt[0]],
-    [lngExt[1], latExt[1]],
+    [lngBounds[0], latBounds[0]],
+    [lngBounds[1], latBounds[1]],
   ];
 }