pager: changing from: value updates to: but keeps size; changing to: value updates size and from:

src/widget.pager.js

@@ -30,11 +30,16 @@ my.Pager = Backbone.View.extend({
   },
   onFormSubmit: function(e) {
     e.preventDefault();
-    var newFrom = parseInt(this.$el.find('input[name="from"]').val());
+    // filter is 0-based; form is 1-based
-    newFrom = Math.min(this.model.recordCount, Math.max(newFrom, 1))-1;
+    var formFrom = parseInt(this.$el.find('input[name="from"]').val())-1; 
-    var newSize = parseInt(this.$el.find('input[name="to"]').val()) - newFrom;
+    var formTo = parseInt(this.$el.find('input[name="to"]').val())-1; 
-    newSize = Math.min(Math.max(newSize, 1), this.model.recordCount);
+    var maxRecord = this.model.recordCount-1;
-    this.model.queryState.set({size: newSize, from: newFrom});
+    if (this.model.queryState.get('from') != formFrom) { // changed from; update from
+      this.model.queryState.set({from: Math.min(maxRecord, Math.max(formFrom, 0))});
+    } else if (this.model.queryState.get('to') != formTo) { // change to; update size
+      var to = Math.min(maxRecord, Math.max(formTo, 0));
+      this.model.queryState.set({size: Math.min(maxRecord+1, Math.max(to-formFrom+1, 1))});
+    }
   },
   onPaginationUpdate: function(e) {
     e.preventDefault();
@@ -44,10 +49,10 @@ my.Pager = Backbone.View.extend({
     var size = this.model.queryState.get('size');
     var updateQuery = false;
     if ($el.parent().hasClass('prev')) {
-      newFrom = Math.max(currFrom - Math.max(0, size), 1)-1;
+      newFrom = Math.max(currFrom - Math.max(0, size), 0);
       updateQuery = newFrom != currFrom;
     } else {
-      newFrom = Math.max(currFrom + size, 1);
+      newFrom = Math.max(currFrom + size, 0);
       updateQuery = (newFrom < this.model.recordCount);
     }
     if (updateQuery) {

test/widget.pager.test.js

@@ -42,6 +42,37 @@ test('basics', function () {
   view.remove();
 });
 
+test('change inputs', function () {
+  var dataset = Fixture.getDataset();
+  var size = parseInt(dataset.recordCount/3);
+  dataset.queryState.set({ size : size }, { silent : true });
+  var view = new recline.View.Pager({
+    model: dataset
+  });
+  $('.fixtures').append(view.el);
+  var toSelector = 'input[name=to]';
+  var fromSelector = 'input[name=from]';
+
+  // change from: update to, keep size
+  var fromVal = size;
+  $(fromSelector).val(fromVal).change();
+  equal($(fromSelector).val(), fromVal);
+  // UI is 1-based but model is zero-based
+  equal(dataset.queryState.get('from'), fromVal-1);
+  equal($(toSelector).val(), fromVal+(size-1));
+  
+  // change to: update from, change size
+  var toVal = dataset.recordCount; 
+  $(toSelector).val(toVal).change();
+  equal($(toSelector).val(), toVal);
+  equal($(fromSelector).val(), fromVal);
+  // UI is 1-based but model is zero-based
+  equal(dataset.queryState.get('from'), fromVal-1);
+  notEqual(dataset.queryState.get('size'), size);
+
+  view.remove();
+});
+
 test('bounds checking', function () {
   var dataset = Fixture.getDataset();
   var size = dataset.recordCount/2 + 1;
@@ -62,10 +93,9 @@ test('bounds checking', function () {
 
   // enter size-1 in from: reloads size-1 - size
   var fromVal = size-1;
-  var toVal = parseInt($(toSelector).val());
   $(fromSelector).val(fromVal).change();
   equal($(fromSelector).val(), fromVal);
-  equal($(toSelector).val(), toVal);
+  equal($(toSelector).val(), fromVal+(size-1));
   // UI is 1-based but model is zero-based
   equal(dataset.queryState.get('from'), fromVal-1);
 
@@ -80,17 +110,17 @@ test('bounds checking', function () {
   // click next on end -> nothing happens
   var queryCalls = querySpy.callCount;
   fromVal = parseInt($(fromSelector).val());
-  toVal = parseInt($(toSelector).val());
+  var toVal = parseInt($(toSelector).val());
   view.$el.find('.next a').click();
   equal(querySpy.callCount, queryCalls);
   equal($(fromSelector).val(), fromVal);
   equal($(toSelector).val(), toVal);
 
-  // reset from to 1
+  // reset from=1
-  // type value past the end in to: 1-recordCount
   fromVal = 1;
+  $(fromSelector).val(fromVal).change();
+  // type value past the end in to: 1-recordCount
   toVal = dataset.recordCount + 10;
-  $(fromSelector).val(fromVal);
   $(toSelector).val(toVal).change();
   equal($(fromSelector).val(), 1);
   equal($(toSelector).val(), dataset.recordCount);