refactor: clippy::return_self_not_must_use (#974)

Cargo.toml

@@ -76,6 +76,7 @@ items_after_statements = "warn"
 missing_const_for_fn = "warn"
 needless_for_each = "warn"
 needless_pass_by_value = "warn"
+return_self_not_must_use = "warn"
 semicolon_if_nothing_returned = "warn"
 trivially_copy_pass_by_ref = "warn"
 use_self = "warn"

src/layout/layout.rs

@@ -391,6 +391,7 @@ impl Layout {
     /// # use ratatui::layout::{Flex, Layout, Constraint::*};
     /// let layout = Layout::horizontal([Length(20), Length(20), Length(20)]).flex(Flex::Legacy);
     /// ```
+    #[must_use = "method moves the value of self and returns the modified value"]
     pub const fn flex(mut self, flex: Flex) -> Self {
         self.flex = flex;
         self
@@ -415,6 +416,7 @@ impl Layout {
     ///
     /// - If the layout has only one item, the spacing will not be applied.
     /// - Spacing will not be applied for [`Flex::SpaceAround`] and [`Flex::SpaceBetween`]
+    #[must_use = "method moves the value of self and returns the modified value"]
     pub const fn spacing(mut self, spacing: u16) -> Self {
         self.spacing = spacing;
         self

src/layout/rect.rs

@@ -111,6 +111,7 @@ impl Rect {
     /// Returns a new `Rect` inside the current one, with the given margin on each side.
     ///
     /// If the margin is larger than the `Rect`, the returned `Rect` will have no area.
+    #[must_use = "method returns the modified value"]
     pub fn inner(self, margin: &Margin) -> Self {
         let doubled_margin_horizontal = margin.horizontal.saturating_mul(2);
         let doubled_margin_vertical = margin.vertical.saturating_mul(2);
@@ -135,6 +136,7 @@ impl Rect {
     /// - Positive `y` moves the whole `Rect` to the bottom, negative to the top.
     ///
     /// See [`Offset`] for details.
+    #[must_use = "method returns the modified value"]
     pub fn offset(self, offset: Offset) -> Self {
         Self {
             x: i32::from(self.x)
@@ -148,6 +150,7 @@ impl Rect {
     }
 
     /// Returns a new `Rect` that contains both the current one and the given one.
+    #[must_use = "method returns the modified value"]
     pub fn union(self, other: Self) -> Self {
         let x1 = min(self.x, other.x);
         let y1 = min(self.y, other.y);
@@ -164,6 +167,7 @@ impl Rect {
     /// Returns a new `Rect` that is the intersection of the current one and the given one.
     ///
     /// If the two `Rect`s do not intersect, the returned `Rect` will have no area.
+    #[must_use = "method returns the modified value"]
     pub fn intersection(self, other: Self) -> Self {
         let x1 = max(self.x, other.x);
         let y1 = max(self.y, other.y);
@@ -227,6 +231,7 @@ impl Rect {
     /// let rect = Rect::new(0, 0, 100, 100).clamp(area);
     /// # }
     /// ```
+    #[must_use = "method returns the modified value"]
     pub fn clamp(self, other: Self) -> Self {
         let width = self.width.min(other.width);
         let height = self.height.min(other.height);

src/widgets/barchart.rs

@@ -118,6 +118,7 @@ impl<'a> BarChart<'a> {
     ///     .data(&[("B0", 0), ("B1", 2), ("B2", 4), ("B3", 3)])
     ///     .data(BarGroup::default().bars(&[Bar::default().value(10), Bar::default().value(20)]));
     /// ```
+    #[must_use = "method moves the value of self and returns the modified value"]
     pub fn data(mut self, data: impl Into<BarGroup<'a>>) -> BarChart<'a> {
         let group: BarGroup = data.into();
         if !group.bars.is_empty() {

src/widgets/block.rs

@@ -234,6 +234,7 @@ impl<'a> Block<'a> {
     /// - [`Block::title_style`]
     /// - [`Block::title_alignment`]
     /// - [`Block::title_position`]
+    #[must_use = "method moves the value of self and returns the modified value"]
     pub fn title<T>(mut self, title: T) -> Block<'a>
     where
         T: Into<Title<'a>>,

src/widgets/block/title.rs

@@ -87,6 +87,7 @@ pub enum Position {
 
 impl<'a> Title<'a> {
     /// Set the title content.
+    #[must_use = "method moves the value of self and returns the modified value"]
     pub fn content<T>(mut self, content: T) -> Title<'a>
     where
         T: Into<Line<'a>>,

src/widgets/calendar.rs

@@ -46,6 +46,7 @@ impl<'a, DS: DateStyler> Monthly<'a, DS> {
     ///
     /// `style` accepts any type that is convertible to [`Style`] (e.g. [`Style`], [`Color`], or
     /// your own type that implements [`Into<Style>`]).
+    #[must_use = "method moves the value of self and returns the modified value"]
     pub fn show_surrounding<S: Into<Style>>(mut self, style: S) -> Self {
         self.show_surrounding = Some(style.into());
         self
@@ -55,6 +56,7 @@ impl<'a, DS: DateStyler> Monthly<'a, DS> {
     ///
     /// `style` accepts any type that is convertible to [`Style`] (e.g. [`Style`], [`Color`], or
     /// your own type that implements [`Into<Style>`]).
+    #[must_use = "method moves the value of self and returns the modified value"]
     pub fn show_weekdays_header<S: Into<Style>>(mut self, style: S) -> Self {
         self.show_weekday = Some(style.into());
         self
@@ -64,6 +66,7 @@ impl<'a, DS: DateStyler> Monthly<'a, DS> {
     ///
     /// `style` accepts any type that is convertible to [`Style`] (e.g. [`Style`], [`Color`], or
     /// your own type that implements [`Into<Style>`]).
+    #[must_use = "method moves the value of self and returns the modified value"]
     pub fn show_month_header<S: Into<Style>>(mut self, style: S) -> Self {
         self.show_month = Some(style.into());
         self
@@ -73,12 +76,14 @@ impl<'a, DS: DateStyler> Monthly<'a, DS> {
     ///
     /// `style` accepts any type that is convertible to [`Style`] (e.g. [`Style`], [`Color`], or
     /// your own type that implements [`Into<Style>`]).
+    #[must_use = "method moves the value of self and returns the modified value"]
     pub fn default_style<S: Into<Style>>(mut self, style: S) -> Self {
         self.default_style = style.into();
         self
     }
 
     /// Render the calendar within a [Block]
+    #[must_use = "method moves the value of self and returns the modified value"]
     pub fn block(mut self, block: Block<'a>) -> Self {
         self.block = Some(block);
         self

src/widgets/canvas.rs

@@ -744,6 +744,7 @@ where
     ///     .marker(symbols::Marker::Block)
     ///     .paint(|ctx| {});
     /// ```
+    #[must_use = "method moves the value of self and returns the modified value"]
     pub const fn marker(mut self, marker: symbols::Marker) -> Canvas<'a, F> {
         self.marker = marker;
         self

src/widgets/gauge.rs

@@ -316,6 +316,7 @@ impl<'a> LineGauge<'a> {
     ///
     /// With `LineGauge`, labels are only on the left, see [`Gauge`] for a centered label.
     /// If the label is not defined, it is the percentage filled.
+    #[must_use = "method moves the value of self and returns the modified value"]
     pub fn label<T>(mut self, label: T) -> Self
     where
         T: Into<Line<'a>>,

src/widgets/table/table.rs

@@ -557,6 +557,7 @@ impl<'a> Table<'a> {
     /// ];
     /// let table = Table::new(Vec::<Row>::new(), widths).flex(Flex::Legacy);
     /// ```
+    #[must_use = "method moves the value of self and returns the modified value"]
     pub const fn flex(mut self, flex: Flex) -> Self {
         self.flex = flex;
         self

src/widgets/tabs.rs

@@ -160,6 +160,7 @@ impl<'a> Tabs<'a> {
     /// # use ratatui::{prelude::*, widgets::Tabs};
     /// let tabs = Tabs::new(vec!["Tab 1", "Tab 2"]).divider("-");
     /// ```
+    #[must_use = "method moves the value of self and returns the modified value"]
     pub fn divider<T>(mut self, divider: T) -> Tabs<'a>
     where
         T: Into<Span<'a>>,
@@ -184,6 +185,7 @@ impl<'a> Tabs<'a> {
     /// # use ratatui::{prelude::*, widgets::Tabs};
     /// let tabs = Tabs::new(vec!["Tab 1", "Tab 2"]).padding("", "");
     /// ```
+    #[must_use = "method moves the value of self and returns the modified value"]
     pub fn padding<T, U>(mut self, left: T, right: U) -> Tabs<'a>
     where
         T: Into<Line<'a>>,
@@ -205,6 +207,7 @@ impl<'a> Tabs<'a> {
     /// # use ratatui::{prelude::*, widgets::Tabs};
     /// let tabs = Tabs::new(vec!["Tab 1", "Tab 2"]).padding_left("->");
     /// ```
+    #[must_use = "method moves the value of self and returns the modified value"]
     pub fn padding_left<T>(mut self, padding: T) -> Tabs<'a>
     where
         T: Into<Line<'a>>,
@@ -224,6 +227,7 @@ impl<'a> Tabs<'a> {
     /// # use ratatui::{prelude::*, widgets::Tabs};
     /// let tabs = Tabs::new(vec!["Tab 1", "Tab 2"]).padding_right("<-");
     /// ```
+    #[must_use = "method moves the value of self and returns the modified value"]
     pub fn padding_right<T>(mut self, padding: T) -> Tabs<'a>
     where
         T: Into<Line<'a>>,