Feat: use auto calculate if min /max is null

src/coord/axisHelper.js

@@ -87,17 +87,6 @@ export function getScaleExtent(scale, model) {
     // (2) When `needCrossZero` and all data is positive/negative, should it be ensured
     // that the results processed by boundaryGap are positive/negative?
 
-    if (min == null) {
-        min = scaleType === 'ordinal'
-            ? (axisDataLen ? 0 : NaN)
-            : originalExtent[0] - boundaryGap[0] * span;
-    }
-    if (max == null) {
-        max = scaleType === 'ordinal'
-            ? (axisDataLen ? axisDataLen - 1 : NaN)
-            : originalExtent[1] + boundaryGap[1] * span;
-    }
-
     if (min === 'dataMin') {
         min = originalExtent[0];
     }
@@ -118,6 +107,17 @@ export function getScaleExtent(scale, model) {
         });
     }
 
+    if (min == null) {
+        min = scaleType === 'ordinal'
+            ? (axisDataLen ? 0 : NaN)
+            : originalExtent[0] - boundaryGap[0] * span;
+    }
+    if (max == null) {
+        max = scaleType === 'ordinal'
+            ? (axisDataLen ? axisDataLen - 1 : NaN)
+            : originalExtent[1] + boundaryGap[1] * span;
+    }
+
     (min == null || !isFinite(min)) && (min = NaN);
     (max == null || !isFinite(max)) && (max = NaN);
 
@@ -208,8 +208,24 @@ function adjustScaleForOverflow(min, max, model, barWidthAndOffset) {
 
 export function niceScaleExtent(scale, model) {
     var extent = getScaleExtent(scale, model);
-    var fixMin = model.getMin() != null;
-    var fixMax = model.getMax() != null;
+    var min = model.getMin();
+    var max = model.getMax();
+    var originalExtent = scale.getExtent();
+
+    if (typeof min === 'function') {
+        min = min({
+            min: originalExtent[0],
+            max: originalExtent[1]
+        });
+    }
+
+    if (typeof max === 'function') {
+        max = max({
+            min: originalExtent[0],
+            max: originalExtent[1]
+        });
+    }
+
     var splitNumber = model.get('splitNumber');
 
     if (scale.type === 'log') {
@@ -220,8 +236,8 @@ export function niceScaleExtent(scale, model) {
     scale.setExtent(extent[0], extent[1]);
     scale.niceExtent({
         splitNumber: splitNumber,
-        fixMin: fixMin,
-        fixMax: fixMax,
+        fixMin: min != null,
+        fixMax: max != null,
         minInterval: (scaleType === 'interval' || scaleType === 'time')
             ? model.get('minInterval') : null,
         maxInterval: (scaleType === 'interval' || scaleType === 'time')

src/echarts.js

@@ -601,7 +601,7 @@ echartsProto.getConnectedDataURL = function (opts) {
             each(canvasList, function (item) {
                 var x = item.left - left;
                 var y = item.top - top;
-                content += '<g transform="translate(' + x + ","
+                content += '<g transform="translate(' + x + ','
                     + y + ')">' + item.dom + '</g>';
             });
             zr.painter.getSvgRoot().innerHTML = content;

test/axis-extrema.html

@@ -68,6 +68,9 @@ <h2>cartesian value axis | xAxis: {min: -10, max: 10}</h2>
         <h2>cartesian value axis | xAxis: {min: function, max: function}</h2>
         <div class="chart" id="main4.1"></div>
 
+        <h2>cartesian value axis | xAxis: {min: function, max: function}</h2>
+        <div class="chart" id="main4.2"></div>
+
         <h2>cartesian time axis | xAxis: {min: 'dataMin', max: 'dataMax'}</h2>
         <div class="chart" id="main5"></div>
 
@@ -463,6 +466,42 @@ <h2>single category axis | singleAxis: {min: function, max: function}</h2>
             });
         </script>
 
+        <script>
+            makeChart('main4.2', {
+                legend: {
+                    data: ['no point', 'one point', 'two points'],
+                    selectedMode: 'single'
+                },
+                tooltip: {
+                    trigger: 'axis',
+                    axisPointer: {
+                        type: 'line'
+                    }
+                },
+                xAxis: {
+                    min: function (value) {
+                        return null
+                    },
+                    max: function (value) {
+                        return null;
+                    }
+                },
+                yAxis: {},
+                series: [{
+                    name: 'no point',
+                    type: 'line',
+                    data: []
+                }, {
+                    name: 'one point',
+                    type: 'line',
+                    data: [[2, 43]]
+                }, {
+                    name: 'two points',
+                    type: 'line',
+                    data: [[2, 43], [4, 99]]
+                }]
+            });
+        </script>