feat: add Style::with() method to overlay one UI Style onto another

crates/bevy_ui/src/ui_node.rs

@@ -468,6 +468,225 @@ impl Style {
  grid_column: GridPlacement::DEFAULT,
  grid_row: GridPlacement::DEFAULT,
  };
+
+ /// Overlays the `patch` onto `self`, ignoring any fields of the `patch` which are at the `DEFAULT` value.
+ ///
+ /// # Example
+ ///
+ /// ```
+ /// # use bevy_ui::{Style, Display, PositionType};
+ /// let patch = Style {
+ /// display: Display::Grid, // non-default
+ /// ..Default::default()
+ /// };
+ ///
+ /// let style = Style {
+ /// position_type: PositionType::Absolute, // non-default
+ /// ..Default::default()
+ /// };
+ ///
+ /// let patched = style.with(patch);
+ ///
+ /// // `patch`'s default `position_type` does not overwrite `style`'s
+ /// assert_eq!(patched.position_type, PositionType::Absolute);
+ /// assert_eq!(patched.display, Display::Grid);
+ /// ```
+ pub fn with(self, patch: Self) -> Self {
+ Style {
+ display: if patch.display == Self::DEFAULT.display {
+ self.display
+ } else {
+ patch.display
+ },
+ position_type: if patch.position_type == Self::DEFAULT.position_type {
+ self.position_type
+ } else {
+ patch.position_type
+ },
+ left: if patch.left == Self::DEFAULT.left {
+ self.left
+ } else {
+ patch.left
+ },
+ right: if patch.right == Self::DEFAULT.right {
+ self.right
+ } else {
+ patch.right
+ },
+ top: if patch.top == Self::DEFAULT.top {
+ self.top
+ } else {
+ patch.top
+ },
+ bottom: if patch.bottom == Self::DEFAULT.bottom {
+ self.bottom
+ } else {
+ patch.bottom
+ },
+ direction: if patch.direction == Self::DEFAULT.direction {
+ self.direction
+ } else {
+ patch.direction
+ },
+ flex_direction: if patch.flex_direction == Self::DEFAULT.flex_direction {
+ self.flex_direction
+ } else {
+ patch.flex_direction
+ },
+ flex_wrap: if patch.flex_wrap == Self::DEFAULT.flex_wrap {
+ self.flex_wrap
+ } else {
+ patch.flex_wrap
+ },
+ align_items: if patch.align_items == Self::DEFAULT.align_items {
+ self.align_items
+ } else {
+ patch.align_items
+ },
+ justify_items: if patch.justify_items == Self::DEFAULT.justify_items {
+ self.justify_items
+ } else {
+ patch.justify_items
+ },
+ align_self: if patch.align_self == Self::DEFAULT.align_self {
+ self.align_self
+ } else {
+ patch.align_self
+ },
+ justify_self: if patch.justify_self == Self::DEFAULT.justify_self {
+ self.justify_self
+ } else {
+ patch.justify_self
+ },
+ align_content: if patch.align_content == Self::DEFAULT.align_content {
+ self.align_content
+ } else {
+ patch.align_content
+ },
+ justify_content: if patch.justify_content == Self::DEFAULT.justify_content {
+ self.justify_content
+ } else {
+ patch.justify_content
+ },
+ margin: if patch.margin == Self::DEFAULT.margin {
+ self.margin
+ } else {
+ patch.margin
+ },
+ padding: if patch.padding == Self::DEFAULT.padding {
+ self.padding
+ } else {
+ patch.padding
+ },
+ border: if patch.border == Self::DEFAULT.border {
+ self.border
+ } else {
+ patch.border
+ },
+ flex_grow: if patch.flex_grow == Self::DEFAULT.flex_grow {
+ self.flex_grow
+ } else {
+ patch.flex_grow
+ },
+ flex_shrink: if patch.flex_shrink == Self::DEFAULT.flex_shrink {
+ self.flex_shrink
+ } else {
+ patch.flex_shrink
+ },
+ flex_basis: if patch.flex_basis == Self::DEFAULT.flex_basis {
+ self.flex_basis
+ } else {
+ patch.flex_basis
+ },
+ width: if patch.width == Self::DEFAULT.width {
+ self.width
+ } else {
+ patch.width
+ },
+ height: if patch.height == Self::DEFAULT.height {
+ self.height
+ } else {
+ patch.height
+ },
+ min_width: if patch.min_width == Self::DEFAULT.min_width {
+ self.min_width
+ } else {
+ patch.min_width
+ },
+ min_height: if patch.min_height == Self::DEFAULT.min_height {
+ self.min_height
+ } else {
+ patch.min_height
+ },
+ max_width: if patch.max_width == Self::DEFAULT.max_width {
+ self.max_width
+ } else {
+ patch.max_width
+ },
+ max_height: if patch.max_height == Self::DEFAULT.max_height {
+ self.max_height
+ } else {
+ patch.max_height
+ },
+ aspect_ratio: if patch.aspect_ratio == Self::DEFAULT.aspect_ratio {
+ self.aspect_ratio
+ } else {
+ patch.aspect_ratio
+ },
+ overflow: if patch.overflow == Self::DEFAULT.overflow {
+ self.overflow
+ } else {
+ patch.overflow
+ },
+ row_gap: if patch.row_gap == Self::DEFAULT.row_gap {
+ self.row_gap
+ } else {
+ patch.row_gap
+ },
+ column_gap: if patch.column_gap == Self::DEFAULT.column_gap {
+ self.column_gap
+ } else {
+ patch.column_gap
+ },
+ grid_auto_flow: if patch.grid_auto_flow == Self::DEFAULT.grid_auto_flow {
+ self.grid_auto_flow
+ } else {
+ patch.grid_auto_flow
+ },
+ grid_template_rows: if patch.grid_template_rows == Self::DEFAULT.grid_template_rows {
+ self.grid_template_rows
+ } else {
+ patch.grid_template_rows
+ },
+ grid_template_columns: if patch.grid_template_columns
+ == Self::DEFAULT.grid_template_columns
+ {
+ self.grid_template_columns
+ } else {
+ patch.grid_template_columns
+ },
+ grid_auto_rows: if patch.grid_auto_rows == Self::DEFAULT.grid_auto_rows {
+ self.grid_auto_rows
+ } else {
+ patch.grid_auto_rows
+ },
+ grid_auto_columns: if patch.grid_auto_columns == Self::DEFAULT.grid_auto_columns {
+ self.grid_auto_columns
+ } else {
+ patch.grid_auto_columns
+ },
+ grid_column: if patch.grid_column == Self::DEFAULT.grid_column {
+ self.grid_column
+ } else {
+ patch.grid_column
+ },
+ grid_row: if patch.grid_row == Self::DEFAULT.grid_row {
+ self.grid_row
+ } else {
+ patch.grid_row
+ },
+ }
+ }
 }
 
 impl Default for Style {