Hover label namelength

src/components/fx/attributes.js

@@ -33,6 +33,20 @@ module.exports = {
             family: extendFlat({}, fontAttrs.family, { arrayOk: true }),
             size: extendFlat({}, fontAttrs.size, { arrayOk: true }),
             color: extendFlat({}, fontAttrs.color, { arrayOk: true })
+        },
+        namelength: {
+            valType: 'integer',
+            min: -1,
+            arrayOk: true,
+            role: 'style',
+            description: [
+                'Sets the length (in number of characters) of the trace name in',
+                'the hover labels for this trace. -1 shows the whole name',
+                'regardless of length. 0-3 shows the first 0-3 characters, and',
+                'an integer >3 will show the whole name if it is less than that',
+                'many characters, but if it is longer, will truncate to',
+                '`namelength - 3` characters and add an ellipsis.'
+            ].join(' ')
         }
     }
 };

src/components/fx/calc.js

@@ -41,6 +41,7 @@ module.exports = function calc(gd) {
         fillFn(trace.hoverlabel.font.size, cd, 'hts');
         fillFn(trace.hoverlabel.font.color, cd, 'htc');
         fillFn(trace.hoverlabel.font.family, cd, 'htf');
+        fillFn(trace.hoverlabel.namelength, cd, 'hnl');
     }
 };
 

src/components/fx/hover.js

@@ -689,7 +689,12 @@ function createHoverText(hoverData, opts, gd) {
             // strip out our pseudo-html elements from d.name (if it exists at all)
             name = svgTextUtils.plainText(d.name || '');
 
-            if(name.length > 15) name = name.substr(0, 12) + '...';
+            var nameLength = Math.round(d.nameLength);
+
+            if(nameLength > -1 && name.length > nameLength) {
+                if(nameLength > 3) name = name.substr(0, nameLength - 3) + '...';
+                else name = name.substr(0, nameLength);
+            }
         }
 
         // used by other modules (initially just ternary) that
@@ -1061,6 +1066,7 @@ function cleanPoint(d, hovermode) {
     fill('fontFamily', 'htf', 'hoverlabel.font.family');
     fill('fontSize', 'hts', 'hoverlabel.font.size');
     fill('fontColor', 'htc', 'hoverlabel.font.color');
+    fill('nameLength', 'hnl', 'hoverlabel.namelength');
 
     d.posref = hovermode === 'y' ? (d.x0 + d.x1) / 2 : (d.y0 + d.y1) / 2;
 

src/components/fx/hoverlabel_defaults.js

@@ -15,5 +15,6 @@ module.exports = function handleHoverLabelDefaults(contIn, contOut, coerce, opts
 
     coerce('hoverlabel.bgcolor', opts.bgcolor);
     coerce('hoverlabel.bordercolor', opts.bordercolor);
+    coerce('hoverlabel.namelength', opts.namelength);
     Lib.coerceFont(coerce, 'hoverlabel.font', opts.font);
 };

src/components/fx/layout_attributes.js

@@ -55,6 +55,20 @@ module.exports = {
                 dflt: constants.HOVERFONTSIZE
             }),
             color: extendFlat({}, fontAttrs.color)
+        },
+        namelength: {
+            valType: 'integer',
+            min: -1,
+            dflt: 15,
+            role: 'style',
+            description: [
+                'Sets the default length (in number of characters) of the trace name in',
+                'the hover labels for all traces. -1 shows the whole name',
+                'regardless of length. 0-3 shows the first 0-3 characters, and',
+                'an integer >3 will show the whole name if it is less than that',
+                'many characters, but if it is longer, will truncate to',
+                '`namelength - 3` characters and add an ellipsis.'
+            ].join(' ')
         }
     }
 };

src/lib/coerce.js

@@ -94,7 +94,7 @@ exports.valObjects = {
             'are coerced to the `dflt`.'
         ].join(' '),
         requiredOpts: [],
-        otherOpts: ['dflt', 'min', 'max'],
+        otherOpts: ['dflt', 'min', 'max', 'arrayOk'],
         coerceFunction: function(v, propOut, dflt, opts) {
             if(v % 1 || !isNumeric(v) ||
                     (opts.min !== undefined && v < opts.min) ||

test/jasmine/tests/fx_test.js

@@ -148,7 +148,8 @@ describe('Fx defaults', function() {
                 family: 'Roboto',
                 size: 40,
                 color: 'pink'
-            }
+            },
+            namelength: 15
         });
 
         expect(out.data[1].hoverlabel).toEqual({
@@ -158,7 +159,8 @@ describe('Fx defaults', function() {
                 family: 'Roboto',
                 size: 20,
                 color: 'red'
-            }
+            },
+            namelength: 15
         });
 
         expect(out.layout.annotations[0].hoverlabel).toEqual({

test/jasmine/tests/hover_label_test.js

@@ -683,7 +683,13 @@ describe('hover info on stacked subplots', function() {
     });
 
     describe('hover info on stacked subplots with shared y-axis', function() {
-        var mock = require('@mocks/stacked_subplots_shared_yaxis.json');
+        var mock = Lib.extendDeep(require('@mocks/stacked_subplots_shared_yaxis.json'));
+        mock.data[0].name = 'Who put the bomp in the bomp bah bomp bah bomp';
+        mock.data[0].hoverlabel = {namelength: -1};
+        mock.data[1].name = 'Who put the ram in the rama lama ding dong';
+        mock.data[1].hoverlabel = {namelength: [2, 4]};
+        mock.data[2].name = 'Who put the bop in the bop shoo bop shoo bop';
+        mock.layout.hoverlabel = {namelength: 10};
 
         beforeEach(function(done) {
             Plotly.plot(createGraphDiv(), mock.data, mock.layout).then(done);
@@ -727,11 +733,11 @@ describe('hover info on stacked subplots', function() {
             expect(d3.selectAll('g.hovertext').size()).toEqual(3);
             var textNodes = d3.selectAll('g.hovertext').selectAll('text');
 
-            expect(textNodes[0][0].innerHTML).toEqual('trace 0');
+            expect(textNodes[0][0].innerHTML).toEqual('Who put the bomp in the bomp bah bomp bah bomp');
             expect(textNodes[0][1].innerHTML).toEqual('1');
-            expect(textNodes[1][0].innerHTML).toEqual('trace 1');
+            expect(textNodes[1][0].innerHTML).toEqual('Wh');
             expect(textNodes[1][1].innerHTML).toEqual('2.1');
-            expect(textNodes[2][0].innerHTML).toEqual('trace 2');
+            expect(textNodes[2][0].innerHTML).toEqual('Who put...');
             expect(textNodes[2][1].innerHTML).toEqual('3');
         });
     });