Fix to ensure date ranges that are 1 day apart still get merged into …

…a single range instead of splitting at this point.

.travis.yml

@@ -2,8 +2,9 @@ language: php
 php:
   - '7.1'
   - '7.2'
+  - '7.4'
 
 before_script:
   - composer install --prefer-dist --dev
 script:
-  - ./vendor/bin/phpunit --configuration phpunit.xml.dist
+  - ./vendor/bin/phpunit --configuration phpunit.xml.dist

README.md

@@ -9,6 +9,8 @@ Available via composer
 ## Usage
 ```PHP
 
+// Each date pair should consist of [earlierDate, laterDate].
+
 $dates = [
     [new DateTime('2019-04-01'), new DateTime('2019-05-01')],
     [new DateTime('2019-05-01'), new DateTime('2019-06-01')],

src/DateMerger.php

@@ -29,7 +29,13 @@ public static function mergeRanges(array $ranges): array
         foreach (array_slice($ranges, 1) as $range) {
             $top = &$stack[count($stack) - 1];
 
-            if ($top[1] < $range[0]) {
+            //check if more than 1 day away otherwise can just be merged.
+            $interval = date_diff($top[1], $range[0]);
+
+            if ($interval->days === 1) {
+              // We assume the date ranges are always formatted [earlier, later]
+              $top[1] = $range[1];
+            } elseif ($top[1] < $range[0]) {
                 // Its a new one so push to stack
                 array_push($stack, $range);
             } elseif
@@ -40,4 +46,4 @@ public static function mergeRanges(array $ranges): array
 
         return $stack;
     }
-}
+}

tests/DateMergerTest.php

@@ -22,6 +22,7 @@ public function testAllOverlapRanges()
             [new DateTime('2019-06-01'), new DateTime('2019-07-01')],
             [new DateTime('2019-07-01'), new DateTime('2019-08-01')],
             [new DateTime('2019-08-01'), new DateTime('2019-09-01')],
+            [new DateTime('2019-09-02'), new DateTime('2018-09-05')],
         ];
 
         $results = DateMerger::mergeRanges($dates);