[fixed] consistent handling of end dates as _exclusive_ ranges

Ensures that date math is done the same way when calculating whether
things fall within a range. All event start-end are considered exclusive
ranges throughout.

fixes jquense#62, fixes jquense#36, fixes jquense#32, closes jquense#67, closes jquense#65

src/Month.jsx

@@ -19,8 +19,9 @@ import Overlay from 'react-overlays/lib/Overlay';
 import BackgroundCells from './BackgroundCells';
 
 import { dateFormat } from './utils/propTypes';
-import { segStyle, inRange, eventSegments, eventLevels, sortEvents } from './utils/eventLevels';
-
+import {
+    segStyle, inRange, eventSegments
+  , endOfRange, eventLevels, sortEvents } from './utils/eventLevels';
 
 let eventsForWeek = (evts, start, end, props) =>
   evts.filter(e => inRange(e, start, end, props));
@@ -132,8 +133,7 @@ let MonthView = React.createClass({
   },
 
   renderWeek(week, weekIdx, content) {
-    let first = week[0]
-    let last = week[week.length - 1]
+    let { first, last } = endOfRange(week);
     let evts = eventsForWeek(this.props.events, week[0], week[week.length - 1], this.props)
 
     evts.sort((a, b) => sortEvents(a, b, this.props))
@@ -200,8 +200,7 @@ let MonthView = React.createClass({
   },
 
   renderRowLevel(segments, week, idx){
-    let first = week[0]
-    let last = week[week.length - 1]
+    let { first, last } = endOfRange(week);
 
     return (
       <EventRow
@@ -217,8 +216,7 @@ let MonthView = React.createClass({
   },
 
   renderShowMore(segments, extraSegments, week, weekIdx) {
-    let first = week[0]
-    let last = week[week.length - 1]
+    let { first, last } = endOfRange(week);
 
     let onClick = slot => this._showMore(segments, week[slot - 1], weekIdx, slot)
 

src/TimeGrid.jsx

@@ -20,10 +20,13 @@ import { notify } from './utils/helpers';
 import { navigate } from './utils/constants';
 import { accessor as get } from './utils/accessors';
 
-import { inRange, eventSegments, eventLevels, sortEvents, segStyle } from './utils/eventLevels';
+import {
+    inRange, eventSegments, endOfRange
+  , eventLevels, sortEvents, segStyle } from './utils/eventLevels';
 
 const MIN_ROWS = 2;
 
+
 let TimeGrid = React.createClass({
 
   propTypes: {
@@ -154,8 +157,7 @@ let TimeGrid = React.createClass({
   },
 
   renderAllDayEvents(range, levels){
-    let first = range[0]
-      , last = range[range.length - 1];
+    let { first, last } = endOfRange(range);
 
     while (levels.length < MIN_ROWS )
       levels.push([])

src/utils/dates.js

@@ -122,6 +122,8 @@ let dates = Object.assign(dateMath, {
       return Math.abs(+dateA - +dateB)
 
     // the .round() handles an edge case
+    // with DST where the total won't be exact
+    // since one day in the range may be shorter/longer by an hour
     return Math.round(Math.abs(
       (+dates.startOf(dateA, unit) / MILLI[unit]) - (+dates.startOf(dateB, unit) / MILLI[unit])
     ))

src/utils/eventLevels.js

@@ -1,16 +1,23 @@
 import dates from './dates';
 import { accessor as get } from './accessors';
 
-export function eventSegments(event, first, last, { startAccessor, endAccessor, culture }){
+export function endOfRange(dateRange, unit = 'day') {
+  return {
+    first: dateRange[0],
+    last: dates.add(dateRange[dateRange.length - 1], 1, unit)
+  }
+}
+
+export function eventSegments(event, first, last, { startAccessor, endAccessor, culture }) {
   let slots = dates.diff(first, last, 'day')
   let start = dates.max(dates.startOf(get(event, startAccessor), 'day'), first);
-  let end = dates.min(dates.ceil(get(event, endAccessor), 'day'), dates.add(last, 1, 'day'))
+  let end = dates.min(dates.ceil(get(event, endAccessor), 'day'), last)
 
+  let padding = dates.diff(first, start, 'day');
   let span = dates.diff(start, end, 'day');
 
-  span = Math.floor(Math.max(Math.min(span, slots), 1));
-
-  let padding = Math.floor(dates.diff(first, start, 'day'));
+  span = Math.min(span, slots)
+  span = Math.max(span, 1);
 
   return {
     event,
@@ -54,14 +61,13 @@ export function eventLevels(rowSegments, limit = Infinity){
 }
 
 export function inRange(e, start, end, { startAccessor, endAccessor }){
-  let eStart = get(e, startAccessor)
-  let eEnd = get(e, endAccessor)
+  let eStart = dates.startOf(get(e, startAccessor), 'day')
+  let eEnd = dates.ceil(get(e, endAccessor), 'day')
 
-  let starts = dates.inRange(eStart, start, end, 'day')
-  let during = dates.lt(eStart, start, 'day') && dates.gt(eEnd, end, 'day')
-  let ends = dates.lt(eStart, start) && dates.inRange(eEnd, start, end, 'day')
+  let startsBeforeEnd = dates.lte(eStart, end, 'day')
+  let endsAfterStart = dates.gt(eEnd, start, 'day')
 
-  return starts || ends || during
+  return startsBeforeEnd && endsAfterStart
 }