[Temporal] Add toJSON to PlainTime

Bug: v8:11544
Change-Id: Iaf440009b2abdf9e90de3ed0e6e02eb35060a65b
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3437889Reviewed-by: Adam Klein <adamk@chromium.org>
Commit-Queue: Frank Tang <ftang@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80682}

src/builtins/builtins-temporal.cc

@@ -82,8 +82,6 @@ TO_BE_IMPLEMENTED(TemporalPlainTimePrototypeToZonedDateTime)
 TO_BE_IMPLEMENTED(TemporalPlainTimePrototypeToLocaleString)
 /* Temporal #sec-temporal.plaintime.prototype.tostring */
 TO_BE_IMPLEMENTED(TemporalPlainTimePrototypeToString)
-/* Temporal #sec-temporal.plaindtimeprototype.tojson */
-TO_BE_IMPLEMENTED(TemporalPlainTimePrototypeToJSON)
 
 /* Temporal.PlaneDateTime */
 /* Temporal #sec-temporal.plaindatetime.compare */
@@ -461,6 +459,7 @@ TEMPORAL_GET_SMI(PlainTime, Nanosecond, iso_nanosecond)
 TEMPORAL_METHOD2(PlainTime, From)
 TEMPORAL_PROTOTYPE_METHOD0(PlainTime, GetISOFields, getISOFields)
 TEMPORAL_VALUE_OF(PlainTime)
+TEMPORAL_PROTOTYPE_METHOD0(PlainTime, ToJSON, toJSON)
 
 // PlainDateTime
 BUILTIN(TemporalPlainDateTimeConstructor) {

src/objects/js-temporal-objects.cc

@@ -1358,6 +1358,77 @@ Handle<String> TemporalDurationToString(Isolate* isolate,
   return builder.Finish().ToHandleChecked();
 }
 
+void ToZeroPaddedDecimalString(IncrementalStringBuilder* builder, int32_t n,
+                               int32_t min_length);
+// #sec-temporal-formatsecondsstringpart
+void FormatSecondsStringPart(IncrementalStringBuilder* builder, int32_t second,
+                             int32_t millisecond, int32_t microsecond,
+                             int32_t nanosecond, Precision precision) {
+  // 1. Assert: second, millisecond, microsecond and nanosecond are integers.
+  // 2. If precision is "minute", return "".
+  if (precision == Precision::kMinute) {
+    return;
+  }
+  // 3. Let secondsString be the string-concatenation of the code unit 0x003A
+  // (COLON) and second formatted as a two-digit decimal number, padded to the
+  // left with zeroes if necessary.
+  builder->AppendCharacter(':');
+  ToZeroPaddedDecimalString(builder, second, 2);
+  // 4. Let fraction be millisecond × 10^6 + microsecond × 10^3 + nanosecond.
+  int32_t fraction = millisecond * 1000000 + microsecond * 1000 + nanosecond;
+  // 5. If fraction is 0, return secondsString.
+  if (fraction == 0) return;
+  // 6. Set fraction to fraction formatted as a nine-digit decimal number,
+  // padded to the left with zeroes if necessary.
+  builder->AppendCharacter('.');
+  // 7. If precision is "auto", then
+  int32_t divisor = 100000000;
+  if (precision == Precision::kAuto) {
+    // a. Set fraction to the
+    // longest possible substring of fraction starting at position 0 and not
+    // ending with the code unit 0x0030 (DIGIT ZERO).
+    do {
+      builder->AppendInt(fraction / divisor);
+      fraction %= divisor;
+      divisor /= 10;
+    } while (fraction > 0);
+  } else {
+    // c. Set fraction to the substring of fraction from 0 to precision.
+    int32_t precision_len = static_cast<int32_t>(precision);
+    DCHECK_LE(0, precision_len);
+    DCHECK_GE(9, precision_len);
+    for (int32_t len = 0; len < precision_len;
+         len++, fraction %= divisor, divisor /= 10) {
+      builder->AppendInt(fraction / divisor);
+    }
+  }
+  // 7. Return the string-concatenation of secondsString, the code unit 0x002E
+  // (FULL STOP), and fraction.
+}
+
+// #sec-temporal-temporaltimetostring
+Handle<String> TemporalTimeToString(Isolate* isolate,
+                                    Handle<JSTemporalPlainTime> temporal_time,
+                                    Precision precision) {
+  // 1. Assert: hour, minute, second, millisecond, microsecond and nanosecond
+  // are integers.
+  IncrementalStringBuilder builder(isolate);
+  // 2. Let hour be ToZeroPaddedDecimalString(hour, 2).
+  ToZeroPaddedDecimalString(&builder, temporal_time->iso_hour(), 2);
+  builder.AppendCharacter('-');
+  // 3. Let minute be ToZeroPaddedDecimalString(minute, 2).
+  ToZeroPaddedDecimalString(&builder, temporal_time->iso_minute(), 2);
+  // 4. Let seconds be ! FormatSecondsStringPart(second, millisecond,
+  // microsecond, nanosecond, precision).
+  FormatSecondsStringPart(&builder, temporal_time->iso_second(),
+                          temporal_time->iso_millisecond(),
+                          temporal_time->iso_microsecond(),
+                          temporal_time->iso_nanosecond(), precision);
+  // 5. Return the string-concatenation of hour, the code unit 0x003A (COLON),
+  // minute, and seconds.
+  return builder.Finish().ToHandleChecked();
+}
+
 }  // namespace
 
 namespace temporal {
@@ -8790,6 +8861,12 @@ MaybeHandle<JSReceiver> JSTemporalPlainTime::GetISOFields(
   return fields;
 }
 
+// #sec-temporal.plaintime.prototype.tojson
+MaybeHandle<String> JSTemporalPlainTime::ToJSON(
+    Isolate* isolate, Handle<JSTemporalPlainTime> temporal_time) {
+  return TemporalTimeToString(isolate, temporal_time, Precision::kAuto);
+}
+
 // #sec-temporal.zoneddatetime
 MaybeHandle<JSTemporalZonedDateTime> JSTemporalZonedDateTime::Constructor(
     Isolate* isolate, Handle<JSFunction> target, Handle<HeapObject> new_target,

src/objects/js-temporal-objects.h

@@ -418,6 +418,10 @@ class JSTemporalPlainTime
   V8_WARN_UNUSED_RESULT static MaybeHandle<JSTemporalPlainTime> NowISO(
       Isolate* isolate, Handle<Object> temporal_time_zone_like);
 
+  // #sec-temporal.plaintime.prototype.tojson
+  V8_WARN_UNUSED_RESULT static MaybeHandle<String> ToJSON(
+      Isolate* isolate, Handle<JSTemporalPlainTime> plain_time);
+
   DECL_PRINTER(JSTemporalPlainTime)
 
   DEFINE_TORQUE_GENERATED_JS_TEMPORAL_HOUR_MINUTE_SECOND()

test/test262/test262.status

@@ -1209,7 +1209,6 @@
   'built-ins/Temporal/PlainTime/prototype/subtract/non-integer-throws-rangeerror': [FAIL],
   'built-ins/Temporal/PlainTime/prototype/subtract/order-of-operations': [FAIL],
   'built-ins/Temporal/PlainTime/prototype/subtract/subclassing-ignored': [FAIL],
-  'built-ins/Temporal/PlainTime/prototype/toJSON/branding': [FAIL],
   'built-ins/Temporal/PlainTime/prototype/toLocaleString/branding': [FAIL],
   'built-ins/Temporal/PlainTime/prototype/toLocaleString/return-string': [FAIL],
   'built-ins/Temporal/PlainTime/prototype/toPlainDateTime/argument-plaindatetime': [FAIL],