msgpack_ext: added string() function for interval

[babyTsakhes]

Added function for converting interval type to string, added tests for this function. Added test for decimal conversion.

Closes #322

[oleg-jukovec]

Please, rebase on the master branch too.

[oleg-jukovec]

@babyTsakhes any updates here?

[babyTsakhes]

testing_mac_os (stable, macos-15)35040Z --- PASS: TestFdDialer_Dial/id_response_error (1.00s)
2026-03-12T10:36:34.6435370Z === RUN TestFdDialer_Dial_requirements
2026-03-12T10:36:34.6455500Z dial_test.go:723:
2026-03-12T10:36:34.6456680Z Error Trace: /Users/runner/work/go-tarantool/go-tarantool/tarantool/go-tarantool/dial_test.go:723
2026-03-12T10:36:34.6457930Z Error: "failed to read greeting: read tcp 127.0.0.1:50143->127.0.0.1:50141: read: bad file descriptor" does not contain "invalid server protocol"
2026-03-12T10:36:34.6458730Z Test: TestFdDialer_Dial_requirements
2026-03-12T10:36:34.6459140Z --- FAIL: TestFdDialer_Dial_requirements

[babyTsakhes]

2026-03-12T10:47:42.2373532Z === RUN TestGracefulShutdown
2026-03-12T10:47:42.2382870Z shutdown_test.go:135:
2026-03-12T10:47:42.2383885Z Error Trace: /home/runner/work/go-tarantool/go-tarantool/shutdown_test.go:135
2026-03-12T10:47:42.2385405Z Error: Expected nil, but got: &fs.PathError{Op:"fork/exec", Path:"/usr/bin/tarantool", Err:0x9}
2026-03-12T10:47:42.2386275Z Test: TestGracefulShutdown
2026-03-12T10:47:42.2386764Z --- FAIL: TestGracefulShutdown (0.00s)
run-tests (1.24, 3.4, false, false) / run-testsrun-tests (1.24, 3.4, false, false) / run-tests

[babyTsakhes]

BenchmarkIntervalStringOld-2 2686132 450.5 ns/op 150 B/op 8 allocs/op
BenchmarkIntervalString-2 2716714 615.6 ns/op 150 B/op 8 allocs/op
PASS
ok github.com/tarantool/go-tarantool/v3/datetime 3.822s
Old version of string is faster.

[babyTsakhes]

func (ival Interval) StringOld() string {
values := []int64{
ival.Year,
ival.Month,
ival.Week,
ival.Day,
ival.Hour,
ival.Min,
ival.Sec,
ival.Nsec,
}

parts := make([]string, 0, 8)
first := true
hasNonZero := false

for i, field := range intervalFields {
	value := values[i]
	if value == 0 {
		continue
	}

	hasNonZero = true
	var sign string
	var absValue int64

	if value < 0 {
		sign = "-"
		absValue = -value
	} else {
		if first {
			sign = "+"
		}
		absValue = value
	}

	unit := field.plur
	if absValue == 1 {
		unit = field.sing
	}

	parts = append(parts, fmt.Sprintf("%s%d %s", sign, absValue, unit))
	first = false
}

if !hasNonZero {
	return "0 seconds"
}

return strings.Join(parts, ", ")

}

func (ival Interval) String() string {
parts := make([]string, 0, 8)
first := true
hasNonZero := false

addPart := func(value int64, sing, plur string) {
	if value == 0 {
		return
	}
	hasNonZero = true
	var sign string
	var absValue int64
	if value < 0 {
		sign = "-"
		absValue = -value
	} else {
		if first {
			sign = "+"
		}
		absValue = value
	}
	unit := plur
	if absValue == 1 {
		unit = sing
	}
	parts = append(parts, fmt.Sprintf("%s%d %s", sign, absValue, unit))
	first = false
}

addPart(ival.Year, "year", "years")
addPart(ival.Month, "month", "months")
addPart(ival.Week, "week", "weeks")
addPart(ival.Day, "day", "days")
addPart(ival.Hour, "hour", "hours")
addPart(ival.Min, "minute", "minutes")
addPart(ival.Sec, "second", "seconds")
addPart(ival.Nsec, "nanosecond", "nanoseconds")

if !hasNonZero {
	return "0 seconds"
}
return strings.Join(parts, ", ")

}

[babyTsakhes]

Please take a look.

[babyTsakhes]

RUN TestConnectionHandlerOpenError
2026-03-17T15:59:55.2847270Z 2026/03/17 15:59:55 tarantool: storing connection to 127.0.0.1:3013 canceled: any error
2026-03-17T15:59:55.2850390Z 2026/03/17 15:59:55 tarantool: connect to 127.0.0.1:3013 failed: storing connection canceled
2026-03-17T15:59:55.2871680Z 2026/03/17 15:59:55 tarantool: storing connection to 127.0.0.1:3014 canceled: any error
2026-03-17T15:59:55.2874940Z 2026/03/17 15:59:55 tarantool: connect to 127.0.0.1:3014 failed: storing connection canceled
2026-03-17T15:59:55.2877160Z --- PASS: TestConnectionHandlerOpenError (0.01s)
2026-03-17T15:59:55.2878680Z === RUN TestConnectionHandlerUpdateError
2026-03-17T15:59:55.3104700Z 2026/03/17 15:59:55 tarantool: connect to 127.0.0.1:3013 failed: failed to read greeting: context canceled
2026-03-17T15:59:55.3122250Z 2026/03/17 15:59:55 tarantool: storing connection to 127.0.0.1:3014 canceled: any error
2026-03-17T15:59:55.3122810Z connection_pool_test.go:1283:
2026-03-17T15:59:55.3123630Z Error Trace: /Users/runner/work/go-tarantool/go-tarantool/tarantool/go-tarantool/pool/connection_pool_test.go:1283
2026-03-17T15:59:55.3124620Z Error: Expected nil, but got: tarantool.ClientError{Code:0x4001, Msg:"connection closed by client"}
2026-03-17T15:59:55.3125170Z Test: TestConnectionHandlerUpdateError
2026-03-17T15:59:55.3125500Z Messages: failed to make ro
2026-03-17T15:59:55.3125820Z 2026/03/17 15:59:55 tarantool: reopen connection to 127.0.0.1:3014 failed: pool is closed
2026-03-17T15:59:55.3126240Z 2026/03/17 15:59:55 tarantool: reopen connection to 127.0.0.1:3013 failed: pool is closed
2026-03-17T15:59:55.3126600Z --- FAIL: TestConnectionHandlerUpdateError (0.03s)
macos

[babyTsakhes]

testing / testing_mac_os (1.24, macos-14) (push)