fix(windows): the status clock prints local time, as Go does

crates/ts_goport/Cargo.toml

@@ -38,6 +38,11 @@ tikv-jemalloc-ctl = { version = "=0.7.0", optional = true }
 # through miow's safe `NamedPipe` API. execute/tsc/compile.rs: Go
 # `os.SameFile` in the Windows `LookPath`. No `unsafe` here (D-W1).
 [target.'cfg(windows)'.dependencies]
+# Go `time.Local` on Windows (time/zoneinfo_windows.go) asks the system for
+# its zone. jiff does the same with `tz-system`; Windows has no zoneinfo
+# files, so the zone data comes with the binary. See
+# execute/tsc/diagnostics.rs `init_local`.
+jiff = { version = "=0.2.37", default-features = false, features = ["std", "tz-system", "tzdb-bundle-platform"] }
 miow = "=0.6.1"
 same-file = "=1.0.6"
 

crates/ts_goport/src/execute/tsc/diagnostics.rs

@@ -307,12 +307,13 @@ pub fn format_status_time(now: SystemTime) -> String {
 }
 
 // ---------------------------------------------------------------------------
-// Go time.Local (go1.27.1 time/zoneinfo_unix.go), for the status clock
+// Go time.Local (go1.27.1 time/zoneinfo_unix.go and zoneinfo_windows.go),
+// for the status clock
 // ---------------------------------------------------------------------------
-// PORT: Go `time.Location` is a `jiff::tz::TimeZone`. Go parses zone files
-// with `LoadLocationFromTZData`; jiff parses the same TZif data (the
-// transitions and the POSIX TZ footer) with `TimeZone::tzif`. This is the
-// Unix path (zoneinfo_unix.go); the port targets Linux.
+// PORT: Go `time.Location` is a `jiff::tz::TimeZone`. On Unix, Go parses
+// zone files with `LoadLocationFromTZData`; jiff parses the same TZif data
+// (the transitions and the POSIX TZ footer) with `TimeZone::tzif`. Windows
+// has its own `init_local` (below).
 
 // Go: time/zoneinfo.go:88 localLoc, :89 localOnce, :91 (*Location).get
 static LOCAL_LOC: OnceLock<jiff::tz::TimeZone> = OnceLock::new();
@@ -336,6 +337,7 @@ const PLATFORM_ZONE_SOURCES: &[&str] = &[
 // Go: time/zoneinfo_unix.go:28 initLocal
 // PORT: Go `syscall.Getenv` gives the raw bytes of the value; so does
 // `as_encoded_bytes` on Unix.
+#[cfg(not(windows))]
 fn init_local() -> jiff::tz::TimeZone {
     // consult $TZ to find the time zone to use.
     // no $TZ means use the system default /etc/localtime.
@@ -370,6 +372,23 @@ fn init_local() -> jiff::tz::TimeZone {
     jiff::tz::TimeZone::UTC
 }
 
+// Go: time/zoneinfo_windows.go:230 initLocal
+// PORT: Go calls `GetTimeZoneInformation` and makes the zone from the
+// Windows standard and daylight rules. jiff asks Windows for the zone key
+// name (`GetDynamicTimeZoneInformation`), maps it to an IANA name (CLDR
+// windowsZones) and takes that zone from the zone data in the binary. For a
+// mapped zone, both give the same civil time now. On failure both fall back
+// to UTC.
+// DIVERGES: jiff reads `TZ` first; Go on Windows does not read it. The
+// logger test `log_time_is_local_time` sets `TZ`, so on Windows it needs
+// this. A Windows zone with no IANA name in jiff's table gives UTC, and jiff
+// does not read the Windows setting that turns off daylight saving time.
+// Go's exact path needs `unsafe` FFI, which the workspace forbids.
+#[cfg(windows)]
+fn init_local() -> jiff::tz::TimeZone {
+    jiff::tz::TimeZone::try_system().unwrap_or(jiff::tz::TimeZone::UTC)
+}
+
 // Go: time/zoneinfo_read.go:531 loadLocation
 // PORT: `initLocal` reads only whether it failed, so the Go first-error
 // bookkeeping is dropped. After the sources Go tries the embedded