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>

test/unit/stdlib/collections/tuple.c3

@@ -0,0 +1,71 @@
+module tuple_test;
+
+struct TestStruct
+{
+    String a;
+    int b;
+}
+
+fn bool TestStruct.eq(self, TestStruct other) @operator(==)
+    => self.a == other.a && self.b == other.b;
+
+
+module tuple_test @test;
+
+import std::collections::pair;
+import std::collections::triple;
+
+
+fn void pair_make_and_unpack()
+{
+    Pair { ulong, String } x = { 0x8034534, "some string" };
+
+    assert(x.first == 0x8034534);
+    assert(x.second == "some string");
+
+    ulong a;
+    String b;
+    x.unpack(&a, &b);
+
+    assert(a == 0x8034534);
+    assert(b == "some string");
+}
+
+fn void pair_compare()
+{
+    Pair { TestStruct, String } x = { {"left", -123}, "right" };
+    Pair { TestStruct, String } y = { {"left", -123}, "right" };
+    Pair { TestStruct, String } z = { {"left", 4096}, "right" };
+
+    assert(x == y);
+    assert(x != z);
+}
+
+fn void triple_make_and_unpack()
+{
+    int myval = 7;
+    Triple { ulong, String, int* } x = { 0xA_DEAD_C0DE, "yet another string", &myval };
+
+    assert(x.first == 0xA_DEAD_C0DE);
+    assert(x.second == "yet another string");
+    assert(x.third == &myval);
+
+    ulong a;
+    String b;
+    int* c;
+    x.unpack(&a, &b, &c);
+
+    assert(a == 0xA_DEAD_C0DE);
+    assert(b == "yet another string");
+    assert(c == &myval);
+}
+
+fn void triple_compare()
+{
+    Triple { TestStruct, String, String } x = { {"in", 42}, "left", "right" };
+    Triple { TestStruct, String, String } y = { {"in", 42}, "left", "right" };
+    Triple { TestStruct, String, String } z = { {"in", 42}, "up", "down" };
+
+    assert(x == y);
+    assert(x != z);
+}

test/unit/stdlib/time/datetime.c3

@@ -49,6 +49,44 @@ fn void test_parse_and_add()
     test::eq(x.day, 4);
 }
 
+fn void datetime_eq()
+{
+	DateTime d = datetime::from_date(1973, APRIL, 27, 12, 23, 55, 34);
+	DateTime d2 = d;
+
+	assert(d == d2);
+
+	d2 = d2.add_days(6);
+	assert(d != d2);
+
+	d2 = d2.add_days(-5);
+	assert(d != d2);
+
+	d2 = d2.add_days(-1);
+	assert(d == d2);
+}
+
+fn void tzdatetime_eq()
+{
+	int offset1_hours = 7;
+	int offset2_hours = -1;
+
+	TzDateTime d1 = datetime::from_date_tz(2022, OCTOBER, 15, 9, 07, 45, gmt_offset: offset1_hours * 3600);
+	TzDateTime d2 = datetime::from_date_tz(2022, OCTOBER, 15, 1, 07, 45, gmt_offset: offset2_hours * 3600);
+
+	assert(d1 == d2);
+
+	d2 = d2.add_years(30);
+	assert(d1 != d2);
+
+	offset1_hours = 12;
+	offset2_hours = -10;
+
+	d1 = datetime::from_date_tz(2022, OCTOBER, 15, 20, 15, 31, gmt_offset: offset1_hours * 3600);
+	d2 = datetime::from_date_tz(2022, OCTOBER, 14, 22, 15, 31, gmt_offset: offset2_hours * 3600);
+	assert(d1 == d2);
+}
+
 fn void test_timezone()
 {
 	int offset_hours = 7;

test/unit/stdlib/time/time.c3

@@ -13,6 +13,20 @@ fn void time_diff()
 	test::eq(t, t2);
 }
 
+fn void time_eq()
+{
+	Time t = time::now();
+	Time t2 = t;
+
+	assert(t == t2);
+
+	t2 += time::US;
+	assert(t != t2);
+
+	t2 -= time::US;
+	assert(t == t2);
+}
+
 fn void clock_diff()
 {
 	Clock c = clock::now();