LibWeb/HTML: Implement valueAsNumber for 'date' input type

Author: https://github.com/shannonbooth
Commit: https://github.com/LadybirdBrowser/ladybird/commit/9585c6c0c78
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/3701

Libraries/LibWeb/HTML/Dates.cpp

@@ -129,22 +129,6 @@ bool is_valid_date_string(StringView value)
     return day >= 1 && day <= AK::days_in_month(year, month);
 }
 
-// https://html.spec.whatwg.org/multipage/common-microsyntaxes.html#parse-a-date-string
-WebIDL::ExceptionOr<GC::Ref<JS::Date>> parse_date_string(JS::Realm& realm, StringView value)
-{
-    // FIXME: Implement spec compliant date string parsing
-    auto parts = value.split_view('-', SplitBehavior::KeepEmpty);
-    if (parts.size() >= 3) {
-        if (auto year = parts.at(0).to_number<u32>(); year.has_value()) {
-            if (auto month = parts.at(1).to_number<u32>(); month.has_value()) {
-                if (auto day_of_month = parts.at(2).to_number<u32>(); day_of_month.has_value())
-                    return JS::Date::create(realm, JS::make_date(JS::make_day(*year, *month - 1, *day_of_month), 0));
-            }
-        }
-    }
-    return WebIDL::SimpleException { WebIDL::SimpleExceptionType::TypeError, "Can't parse date string"sv };
-}
-
 // https://html.spec.whatwg.org/multipage/common-microsyntaxes.html#valid-local-date-and-time-string
 bool is_valid_local_date_and_time_string(StringView value)
 {
@@ -363,4 +347,58 @@ Optional<WeekYearAndWeek> parse_a_week_string(StringView input_view)
     return WeekYearAndWeek { year, week };
 }
 
+// https://html.spec.whatwg.org/multipage/common-microsyntaxes.html#parse-a-date-component
+static Optional<YearMonthDay> parse_a_date_component(GenericLexer& input)
+{
+    // 1. Parse a month component to obtain year and month. If this returns nothing, then fail.
+    auto maybe_month_component = parse_a_month_component(input);
+    if (!maybe_month_component.has_value())
+        return {};
+    auto month_component = maybe_month_component.value();
+
+    // 2. Let maxday be the number of days in month month of year year.
+    u32 maxday = AK::days_in_month(month_component.year, month_component.month);
+
+    // 3. If position is beyond the end of input or if the character at position is not a U+002D HYPHEN-MINUS character, then fail.
+    //    Otherwise, move position forwards one character.
+    if (!input.consume_specific('-'))
+        return {};
+
+    // 4. Collect a sequence of code points that are ASCII digits from input given position. If the collected sequence is not
+    //    exactly two characters long, then fail. Otherwise, interpret the resulting sequence as a base-ten integer. Let that
+    //    number be the day.
+    auto day_string = input.consume_while(is_ascii_digit);
+    if (day_string.length() != 2)
+        return {};
+    auto day = day_string.to_number<u32>().value();
+
+    // 5. If day is not a number in the range 1 ≤ day ≤ maxday, then fail.
+    if (day < 1 || day > maxday)
+        return {};
+
+    // 6. Return year, month, and day.
+    return YearMonthDay { month_component.year, month_component.month, day };
+}
+
+// https://html.spec.whatwg.org/multipage/common-microsyntaxes.html#parse-a-date-string
+Optional<YearMonthDay> parse_a_date_string(StringView input_view)
+{
+    // 1. Let input be the string being parsed.
+    // 2. Let position be a pointer into input, initially pointing at the start of the string.
+    GenericLexer input { input_view };
+
+    // 3. Parse a date component to obtain year, month, and day. If this returns nothing, then fail.
+    auto year_month_day = parse_a_date_component(input);
+    if (!year_month_day.has_value())
+        return {};
+
+    // 4. If position is not beyond the end of input, then fail.
+    if (!input.is_eof())
+        return {};
+
+    // 5. Let date be the date with year year, month month, and day day.
+    // 6. Return date.
+    return year_month_day.release_value();
+}
+
 }

Libraries/LibWeb/HTML/Dates.h

@@ -17,7 +17,6 @@ u32 week_number_of_the_last_day(u64 year);
 bool is_valid_week_string(StringView value);
 bool is_valid_month_string(StringView value);
 bool is_valid_date_string(StringView value);
-WebIDL::ExceptionOr<GC::Ref<JS::Date>> parse_date_string(JS::Realm& realm, StringView value);
 bool is_valid_local_date_and_time_string(StringView value);
 String normalize_local_date_and_time_string(String const& value);
 bool is_valid_time_string(StringView value);
@@ -35,6 +34,14 @@ struct WeekYearAndWeek {
 };
 Optional<WeekYearAndWeek> parse_a_week_string(StringView);
 
+struct YearMonthDay {
+    u32 year;
+    u32 month;
+    u32 day;
+};
+
+Optional<YearMonthDay> parse_a_date_string(StringView);
+
 i32 number_of_months_since_unix_epoch(YearAndMonth);
 
 }

Libraries/LibWeb/HTML/HTMLInputElement.cpp

@@ -11,6 +11,7 @@
  * SPDX-License-Identifier: BSD-2-Clause
  */
 
+#include <LibCore/DateTime.h>
 #include <LibJS/Runtime/Date.h>
 #include <LibJS/Runtime/NativeFunction.h>
 #include <LibWeb/Bindings/HTMLInputElementPrototype.h>
@@ -2094,6 +2095,22 @@ static Optional<double> convert_week_string_to_number(StringView input)
     return UnixDateTime::from_iso8601_week(parsed_week->week_year, parsed_week->week).milliseconds_since_epoch();
 }
 
+// https://html.spec.whatwg.org/multipage/input.html#date-state-(type=date):concept-input-value-number-string
+static Optional<double> convert_date_string_to_number(StringView input)
+{
+    // The algorithm to convert a string to a number, given a string input, is as follows: If parsing a date
+    // from input results in an error, then return an error; otherwise, return the number of milliseconds
+    // elapsed from midnight UTC on the morning of 1970-01-01 (the time represented by the value
+    // "1970-01-01T00:00:00.0Z") to midnight UTC on the morning of the parsed date, ignoring leap seconds.
+    auto maybe_date = parse_a_date_string(input);
+    if (!maybe_date.has_value())
+        return {};
+    auto date = maybe_date.value();
+
+    auto date_time = UnixDateTime::from_unix_time_parts(date.year, date.month, date.day, 0, 0, 0, 0);
+    return date_time.milliseconds_since_epoch();
+}
+
 // https://html.spec.whatwg.org/multipage/input.html#concept-input-value-string-number
 Optional<double> HTMLInputElement::convert_string_to_number(StringView input) const
 {
@@ -2111,6 +2128,9 @@ Optional<double> HTMLInputElement::convert_string_to_number(StringView input) co
     if (type_state() == TypeAttributeState::Week)
         return convert_week_string_to_number(input);
 
+    if (type_state() == TypeAttributeState::Date)
+        return convert_date_string_to_number(input);
+
     dbgln("HTMLInputElement::convert_string_to_number() not implemented for input type {}", type());
     return {};
 }
@@ -2156,6 +2176,16 @@ static String convert_number_to_week_string(double input)
     return MUST(String::formatted("{:04d}-W{:02d}", year, week));
 }
 
+// https://html.spec.whatwg.org/multipage/input.html#date-state-(type=date):concept-input-value-number-string
+static String convert_number_to_date_string(double input)
+{
+    // The algorithm to convert a number to a string, given a number input, is as follows: Return a valid
+    // date string that represents the date that, in UTC, is current input milliseconds after midnight UTC
+    // on the morning of 1970-01-01 (the time represented by the value "1970-01-01T00:00:00.0Z").
+    auto date = Core::DateTime::from_timestamp(input / 1000.);
+    return MUST(date.to_string("%Y-%m-%d"sv, Core::DateTime::LocalTime::No));
+}
+
 // https://html.spec.whatwg.org/multipage/input.html#concept-input-value-string-number
 String HTMLInputElement::convert_number_to_string(double input) const
 {
@@ -2173,6 +2203,9 @@ String HTMLInputElement::convert_number_to_string(double input) const
     if (type_state() == TypeAttributeState::Week)
         return convert_number_to_week_string(input);
 
+    if (type_state() == TypeAttributeState::Date)
+        return convert_number_to_date_string(input);
+
     dbgln("HTMLInputElement::convert_number_to_string() not implemented for input type {}", type());
     return {};
 }
@@ -2183,12 +2216,13 @@ WebIDL::ExceptionOr<GC::Ptr<JS::Date>> HTMLInputElement::convert_string_to_date(
     // https://html.spec.whatwg.org/multipage/input.html#date-state-(type=date):concept-input-value-string-date
     if (type_state() == TypeAttributeState::Date) {
         // If parsing a date from input results in an error, then return an error;
-        auto maybe_date = parse_date_string(realm(), input);
-        if (maybe_date.is_exception())
-            return maybe_date.exception();
+        auto maybe_date = parse_a_date_string(input);
+        if (!maybe_date.has_value())
+            return WebIDL::SimpleException { WebIDL::SimpleExceptionType::TypeError, "Can't parse date string"sv };
+        auto date = maybe_date.value();
 
         // otherwise, return a new Date object representing midnight UTC on the morning of the parsed date.
-        return maybe_date.value();
+        return JS::Date::create(realm(), JS::make_date(JS::make_day(date.year, date.month - 1, date.day), 0));
     }
 
     // https://html.spec.whatwg.org/multipage/input.html#time-state-(type=time):concept-input-value-string-date

Tests/LibWeb/Text/expected/HTML/HTMLInputElement-valueAsNumber.txt

@@ -31,7 +31,7 @@ tel threw exception: InvalidStateError: valueAsNumber: Invalid input type used
 url threw exception: InvalidStateError: valueAsNumber: Invalid input type used
 email threw exception: InvalidStateError: valueAsNumber: Invalid input type used
 password threw exception: InvalidStateError: valueAsNumber: Invalid input type used
-date did not throw: NaN
+date did not throw: 0
 month did not throw: 100
 week did not throw: 345600000
 time did not throw: NaN

Tests/LibWeb/Text/expected/wpt-import/html/semantics/forms/the-input-element/input-valueasnumber.txt

@@ -2,19 +2,19 @@ Harness status: OK
 
 Found 60 tests
 
-43 Pass
-17 Fail
+48 Pass
+12 Fail
 Pass	valueAsNumber getter on type date (actual value: , expected valueAsNumber: NaN)
 Pass	valueAsNumber getter on type date (actual value: 0000-12-10, expected valueAsNumber: NaN)
 Pass	valueAsNumber getter on type date (actual value: 2019-00-12, expected valueAsNumber: NaN)
 Pass	valueAsNumber getter on type date (actual value: 2019-12-00, expected valueAsNumber: NaN)
 Pass	valueAsNumber getter on type date (actual value: 2019-13-10, expected valueAsNumber: NaN)
 Pass	valueAsNumber getter on type date (actual value: 2019-02-29, expected valueAsNumber: NaN)
-Fail	valueAsNumber getter on type date (actual value: 2019-12-10, expected valueAsNumber: 1575936000000)
-Fail	valueAsNumber getter on type date (actual value: 2016-02-29, expected valueAsNumber: 1456704000000)
-Fail	valueAsNumber setter on type date (actual valueAsNumber: 0, expected value: 1970-01-01)
-Fail	valueAsNumber setter on type date (actual valueAsNumber: 1575936000000, expected value: 2019-12-10)
-Fail	valueAsNumber setter on type date (actual valueAsNumber: 1456704000000, expected value: 2016-02-29)
+Pass	valueAsNumber getter on type date (actual value: 2019-12-10, expected valueAsNumber: 1575936000000)
+Pass	valueAsNumber getter on type date (actual value: 2016-02-29, expected valueAsNumber: 1456704000000)
+Pass	valueAsNumber setter on type date (actual valueAsNumber: 0, expected value: 1970-01-01)
+Pass	valueAsNumber setter on type date (actual valueAsNumber: 1575936000000, expected value: 2019-12-10)
+Pass	valueAsNumber setter on type date (actual valueAsNumber: 1456704000000, expected value: 2016-02-29)
 Pass	valueAsNumber getter on type month (actual value: , expected valueAsNumber: NaN)
 Pass	valueAsNumber getter on type month (actual value: 0000-12, expected valueAsNumber: NaN)
 Pass	valueAsNumber getter on type month (actual value: 2019-00, expected valueAsNumber: NaN)