fix scatterpolar line axis expansion for >1e5 pts

Author: etpinard

src/traces/scattergl/index.js

@@ -92,9 +92,12 @@ function calc(gd, trace) {
     // For graphs with very large number of points and array marker.size,
     // use average marker size instead to speed things up.
     setFirstScatter(fullLayout, trace);
-    var ppad = len < TOO_MANY_POINTS ?
-        calcMarkerSize(trace, len) :
-        2 * (opts.marker.sizeAvg || Math.max(opts.marker.size, 3));
+    var ppad;
+    if(len < TOO_MANY_POINTS) {
+        ppad = calcMarkerSize(trace, len);
+    } else if(opts.marker) {
+        ppad = 2 * (opts.marker.sizeAvg || Math.max(opts.marker.size, 3));
+    }
     calcAxisExpansion(gd, trace, xa, ya, x, y, ppad);
     if(opts.errorX) expandForErrorBars(trace, xa, opts.errorX);
     if(opts.errorY) expandForErrorBars(trace, ya, opts.errorY);

test/jasmine/tests/gl2d_plot_interact_test.js

@@ -1305,10 +1305,14 @@ describe('Test scattergl autorange:', function() {
     });
 
     describe('should return the approximative values for ~big~ data', function() {
+        var gd;
+
         beforeEach(function() {
+            gd = createGraphDiv();
             // to avoid expansive draw calls (which could be problematic on CI)
             spyOn(ScatterGl, 'plot').and.callFake(function(gd) {
                 gd._fullLayout._plots.xy._scene.scatter2d = {draw: function() {}};
+                gd._fullLayout._plots.xy._scene.line2d = {draw: function() {}};
             });
         });
 
@@ -1327,8 +1331,6 @@ describe('Test scattergl autorange:', function() {
         }
 
         it('@gl - case scalar marker.size', function(done) {
-            var gd = createGraphDiv();
-
             Plotly.newPlot(gd, [{
                 type: 'scattergl',
                 mode: 'markers',
@@ -1345,8 +1347,6 @@ describe('Test scattergl autorange:', function() {
         });
 
         it('@gl - case array marker.size', function(done) {
-            var gd = createGraphDiv();
-
             Plotly.newPlot(gd, [{
                 type: 'scattergl',
                 mode: 'markers',
@@ -1361,5 +1361,19 @@ describe('Test scattergl autorange:', function() {
             .catch(failTest)
             .then(done);
         });
+
+        it('@gl - case mode:lines', function(done) {
+            Plotly.newPlot(gd, [{
+                type: 'scattergl',
+                mode: 'lines',
+                y: y,
+            }])
+            .then(function() {
+                expect(gd._fullLayout.xaxis.range).toBeCloseToArray([0, N - 1], 2, 'x range');
+                expect(gd._fullLayout.yaxis.range).toBeCloseToArray([-0.0555, 1.0555], 2, 'y range');
+            })
+            .catch(failTest)
+            .then(done);
+        });
     });
 });