Struct MaterialDate 

pub struct MaterialDate { /* private fields */ }

A whole calendar day: year, month (1..=12), day (1..=days_in_month).

Named MaterialDate rather than a bare Date because this crate flat re-exports every widget/spec type at its root (frust_material::MaterialDate), where a bare Date would collide with any other catalog or app type of the same name — the same reason crate::MaterialTokens/crate::MaterialMotion carry the prefix.

Ordering is chronological (Ord over (year, month, day), which is equivalent to ordering by Self::epoch_day because every field is normalized on construction), so first_date <= day && day <= last_date is the bounds test the whole family uses.

Implementations

impl MaterialDate

pub fn new(year: i32, month: u32, day: u32) -> Self

The nearest real date to (year, month, day): the year clamped to MIN_YEAR..=MAX_YEAR, the month to 1..=12, the day to that month’s own length. See the module docs’ clamping note.

use frust_material::MaterialDate;

// 31 February resolves to the 29th in a leap year, the 28th otherwise.
assert_eq!(MaterialDate::new(2024, 2, 31), MaterialDate::new(2024, 2, 29));
assert_eq!(MaterialDate::new(2023, 2, 31), MaterialDate::new(2023, 2, 28));

pub fn year(self) -> i32

This date’s year.

pub fn month(self) -> u32

This date’s month, 1..=12.

pub fn day(self) -> u32

This date’s day of the month, 1..=days_in_month.

pub fn first_of_month(self) -> Self

The first of this date’s own month — the reference’s M3EDatePickerUtils.getMonth(date.year, date.month), which is how every “displayed month” value in this family is normalized.

pub fn epoch_day(self) -> i64

Days since 1970-01-01 (negative before it) — Howard Hinnant’s days_from_civil. The one primitive Self::weekday_index and Self::days_until are derived from.

use frust_material::MaterialDate;

assert_eq!(MaterialDate::new(1970, 1, 1).epoch_day(), 0);
assert_eq!(MaterialDate::new(1969, 12, 31).epoch_day(), -1);

pub fn days_until(self, other: Self) -> i64

Signed day count from self to other (other - self).

pub fn weekday_index(self) -> u32

This date’s weekday as a Sunday-first index: 0 Sunday through 6 Saturday.

The reference reads Dart’s DateTime.weekday (Monday-first, 1..=7) and folds it with % 7 (M3ECalendarLabels.firstWeekday); this returns the folded value directly, since every consumer here — the grid’s leading-blank count and the weekday header row — wants the Sunday-first one.

use frust_material::MaterialDate;

// 2000-01-01 was a Saturday; 2026-08-20 a Thursday.
assert_eq!(MaterialDate::new(2000, 1, 1).weekday_index(), 6);
assert_eq!(MaterialDate::new(2026, 8, 20).weekday_index(), 4);

pub fn days_in_this_month(self) -> u32

How many days this date’s own month has.

pub fn add_months(self, delta: i32) -> Self

This date shifted by delta whole months, keeping the day of the month where the target month is long enough and shortening it where it is not — the reference’s addMonthsToMonthDate + normalizeSelectedDay pair.

use frust_material::MaterialDate;

let jan31 = MaterialDate::new(2026, 1, 31);
assert_eq!(jan31.add_months(1), MaterialDate::new(2026, 2, 28));
assert_eq!(jan31.add_months(-1), MaterialDate::new(2025, 12, 31));

pub fn month_delta(self, other: Self) -> i32

Whole months from self’s month to other’s — the reference’s monthDelta. Day-of-month is ignored on both sides.

pub fn clamp_to(self, first: Self, last: Self) -> Self

self clamped into first..=last (the reference’s clampDate). A reversed pair (last < first) collapses onto first, so a caller that hands the bounds in the wrong order gets a defined date rather than a panic.

pub fn is_within(self, first: Self, last: Self) -> bool

Whether self lies within first..=last, inclusive — the reference’s isSelectable bounds half (its optional predicate is applied by the widget, which owns the caller-supplied closure).

pub fn format_compact(self) -> String

This date in the compact, parseable mm/dd/yyyy form — Flutter’s MaterialLocalizations.formatCompactDate for en_US, which is the format the reference’s input mode both renders and parses.

See crate::DatePickerStrings for why this port ships one fixed English/US format rather than a locale-resolved one.

use frust_material::MaterialDate;

assert_eq!(MaterialDate::new(2026, 8, 20).format_compact(), "08/20/2026");

pub fn parse_compact(text: &str) -> Option<Self>

Parse the compact mm/dd/yyyy form back into a date, or None if the text is not exactly that — Flutter’s parseCompactDate for en_US, which is what drives the input mode’s format error.

Rejects (rather than clamping — see the module docs): a part count other than three, any non-ASCII-digit character, an empty part, a month outside 1..=12, a day outside the month’s own length, and a year outside MIN_YEAR..=MAX_YEAR. Surrounding whitespace is trimmed first, so a paste with a trailing newline still parses.

use frust_material::MaterialDate;

assert_eq!(MaterialDate::parse_compact("08/20/2026"), Some(MaterialDate::new(2026, 8, 20)));
assert_eq!(MaterialDate::parse_compact("8/2/2026"), Some(MaterialDate::new(2026, 8, 2)));
assert_eq!(MaterialDate::parse_compact("02/30/2026"), None);
assert_eq!(MaterialDate::parse_compact("2026-08-20"), None);

Trait Implementations

impl Clone for MaterialDate

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for MaterialDate

impl Debug for MaterialDate

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Eq for MaterialDate

impl Hash for MaterialDate

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Ord for MaterialDate

fn cmp(&self, other: &Self) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

fn clamp_to<R>(self, range: R) -> Self

where Self: Sized, R: ClampBounds<Self>,

🔬This is a nightly-only experimental API. (clamp_to)

Restrict a value to a certain range.

impl PartialEq for MaterialDate

fn eq(&self, other: &Self) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl PartialOrd for MaterialDate

fn partial_cmp(&self, other: &Self) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl StructuralPartialEq for MaterialDate