Add same-date? first and last-day-of-the-month? functions

src/cljs_time/predicates.cljs

@@ -6,7 +6,8 @@
 
   Is it January?
   (january? (clj-time.core/date-time 2011 1 1))"
-  (:require [cljs-time.core :as time]))
+  (:require [cljs-time.core :as time]
+            [cljs-time.coerce :as coerce]))
 
 ;; days of the week
 (defn monday? [date-time]
@@ -73,3 +74,15 @@
 
 (defn december? [date-time]
   (= (time/month date-time) 12))
+
+;;First and last day of month checks
+(defn last-day-of-month? [date-time]
+  (= (time/last-day-of-the-month date-time) date-time))
+
+(defn first-day-of-month? [date-time]
+  (= (time/first-day-of-the-month date-time) date-time))
+
+(defn same-date?
+  "Compares two date times to see if they are the same date"
+  [this-date-time that-date-time]
+  (= (coerce/to-local-date this-date-time) (coerce/to-local-date that-date-time)))

test/cljs_time/predicates_test.cljs

@@ -6,7 +6,9 @@
     [cljs-time.predicates :refer
      [monday? tuesday? wednesday? thursday? friday? saturday? sunday? weekend?
       weekday? january? february? march? april? may? june? july? august?
-      september? october? november? december?]]))
+      september? october? november? december?
+      last-day-of-month? first-day-of-month?
+      same-date?]]))
 
 (deftest test-days-of-the-week
   (is (= true (monday? (date-time 2012 9 10))))
@@ -36,3 +38,16 @@
   (is (= true (november? (date-time 2012 11 16))))
   (is (= true (december? (date-time 2012 12 16))))
   (is (= false (january? (date-time 2012 12 31)))))
+
+(deftest test-first-and-last-day-of-month
+  (is (= false (first-day-of-month? (date-time 2016 2 2))))
+  (is (= true (first-day-of-month? (date-time 2016 2 1))))
+  (is (= false (last-day-of-month? (date-time 2016 2 28))))
+  (is (= true (last-day-of-month? (date-time 2016 1 31))))
+  (is (= true (last-day-of-month? (date-time 2016 2 29)))))
+
+(deftest test-same-date
+  (is (= true (same-date? (date-time 2013 10 8) (date-time 2013 10 8))))
+  (is (= true (same-date? (date-time 2012 1 1) (date-time 2012 1 1))))
+  (is (= false (same-date? (date-time 2012 2 2) (date-time 2012 1 1))))
+  (is (= false (same-date? (date-time 2011 2 2) (date-time 2012 2 2)))))