Pair and Triple Compare w/ Unit Tests (#2359)

* Pair and Triple Compare w/ Unit Tests
* scope creep myself by adding date-time eq op
* make Pair and Triple printable
* Update releasenotes. Restrict equals on tuples to when underlying type supports `==`. Remove unnecessary Time.eq.

---------

Co-authored-by: Christoffer Lerno <christoffer@aegik.com>

lib/std/collections/tuple.c3

@@ -1,11 +1,17 @@
 module std::collections::pair{Type1, Type2};
+import std::io;
 
-struct Pair
+struct Pair (Printable)
 {
 	Type1 first;
 	Type2 second;
 }
 
+fn usz? Pair.to_format(&self, Formatter* f) @dynamic
+{
+	return f.printf("{ %s, %s }", self.first, self.second);
+}
+
 <*
  @param [&out] a
  @param [&out] b
@@ -18,15 +24,27 @@ macro void Pair.unpack(&self, a, b)
 	*b = self.second;
 }
 
-module std::collections::triple{Type1, Type2, Type3};
+fn bool Pair.equal(self, Pair other) @operator(==) @if (types::has_equals(Type1) &&& types::has_equals(Type2))
+{
+	return self.first == other.first && self.second == other.second;
+}
 
-struct Triple
+
+
+module std::collections::triple{Type1, Type2, Type3};
+import std::io;
+
+struct Triple (Printable)
 {
 	Type1 first;
 	Type2 second;
 	Type3 third;
 }
 
+fn usz? Triple.to_format(&self, Formatter* f) @dynamic
+{
+	return f.printf("{ %s, %s, %s }", self.first, self.second, self.third);
+}
 <*
  @param [&out] a
  @param [&out] b
@@ -42,6 +60,12 @@ macro void Triple.unpack(&self, a, b, c)
 	*c = self.third;
 }
 
+fn bool Triple.equal(self, Triple other) @operator(==) @if (types::has_equals(Type1) &&& types::has_equals(Type2) &&& types::has_equals(Type3))
+{
+	return self.first == other.first && self.second == other.second && self.third == other.third;
+}
+
+
 module std::collections::tuple{Type1, Type2};
 
 struct Tuple @deprecated("Use 'Pair' instead")

lib/std/core/types.c3

@@ -339,6 +339,8 @@ macro bool is_same_vector_type($Type1, $Type2) @const
 	$endif
 }
 
+macro bool has_equals($Type) @const => $defined(($Type){} == ($Type){});
+
 macro bool is_equatable_type($Type) @const
 {
 	$if $defined($Type.less) || $defined($Type.compare_to) || $defined($Type.equals):

lib/std/time/datetime.c3

@@ -112,6 +112,11 @@ fn TzDateTime TzDateTime.to_gmt_offset(self, int gmt_offset) {
 	return { dt, gmt_offset };
 }
 
+fn bool TzDateTime.eq(self, TzDateTime other) @operator(==) @inline
+{
+	return self.to_gmt_offset(0).time == other.to_gmt_offset(0).time;
+}
+
 <*
  @require day >= 1 && day < 32
  @require hour >= 0 && hour < 24
@@ -257,3 +262,5 @@ fn Duration DateTime.diff_us(self, DateTime from) @operator(-)
 {
 	return self.time.diff_us(from.time);
 }
+
+fn bool DateTime.eq(self, DateTime other) @operator(==) @inline => self.time == other.time;