/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at
https://mozilla.org/MPL/2.0/. */
//! Value information for devtools.
use crate::arc_slice::ArcSlice;
use crate::owned_slice::OwnedSlice;
use servo_arc::Arc;
use std::ops::Range;
use std::sync::Arc as StdArc;
use thin_vec::ThinVec;
/// Type of value that a property supports. This is used by Gecko's
/// devtools to make sense about value it parses, and types listed
/// here should match InspectorPropertyType in InspectorUtils.webidl.
///
/// XXX This should really be a bitflags rather than a namespace mod,
/// but currently we cannot use bitflags in const.
#[allow(non_snake_case)]
pub mod CssType {
/// <color>
pub const COLOR: u8 = 1 << 0;
/// <gradient>
pub const GRADIENT: u8 = 1 << 1;
/// <timing-function>
pub const TIMING_FUNCTION: u8 = 1 << 2;
}
/// See SpecifiedValueInfo::collect_completion_keywords.
pub type KeywordsCollectFn<'a> = &'a mut dyn FnMut(&[&'static str]);
/// Information of values of a given specified value type.
///
/// This trait is derivable with `#[derive(SpecifiedValueInfo)]`.
///
/// The algorithm traverses the type definition. For `SUPPORTED_TYPES`,
/// it puts an or'ed value of `SUPPORTED_TYPES` of all types it finds.
/// For `collect_completion_keywords`, it recursively invokes this
/// method on types found, and lists all keyword values and function
/// names following the same rule as `ToCss` in that method.
///
/// Some attributes of `ToCss` can affect the behavior, specifically:
/// * If `#[css(function)]` is found, the content inside the annotated
/// variant (or the whole type) isn't traversed, only the function
/// name is listed in `collect_completion_keywords`.
/// * If `#[css(skip)]` is found, the content inside the variant or
/// field is ignored.
/// * Values listed in `#[css(if_empty)]`, `#[parse(aliases)]`, and
/// `#[css(keyword)]` are added into `collect_completion_keywords`.
///
/// In addition to `css` attributes, it also has `value_info` helper
/// attributes, including:
/// * `#[value_info(ty = "TYPE")]` can be used to specify a constant
/// from `CssType` to `SUPPORTED_TYPES`.
/// * `#[value_info(other_values = "value1,value2")]` can be used to
/// add other values related to a field, variant, or the type itself
/// into `collect_completion_keywords`.
/// * `#[value_info(starts_with_keyword)]` can be used on variants to
/// add the name of a non-unit variant (serialized like `ToCss`) into
/// `collect_completion_keywords`.
pub trait SpecifiedValueInfo {
/// Supported CssTypes by the given value type.
///
/// XXX This should be typed CssType when that becomes a bitflags.
/// Currently we cannot do so since bitflags cannot be used in constant.
const SUPPORTED_TYPES: u8 = 0;
/// Collect value starting words for the given specified value type.
/// This includes keyword and function names which can appear at the
/// beginning of a value of this type.
///
/// Caller should pass in a callback function to accept the list of
/// values. The callback function can be called multiple times, and
/// some values passed to the callback may be duplicate.
fn collect_completion_keywords(_f: KeywordsCollectFn) {}
}
impl SpecifiedValueInfo for bool {}
impl SpecifiedValueInfo for f32 {}
impl SpecifiedValueInfo for i8 {}
impl SpecifiedValueInfo for i32 {}
impl SpecifiedValueInfo for u8 {}
impl SpecifiedValueInfo for u16 {}
impl SpecifiedValueInfo for u32 {}
impl SpecifiedValueInfo for usize {}
impl SpecifiedValueInfo for str {}
impl SpecifiedValueInfo for String {}
impl SpecifiedValueInfo for crate::owned_str::OwnedStr {}
#[cfg(feature = "servo")]
impl SpecifiedValueInfo for ::servo_atoms::Atom {}
#[cfg(feature = "servo")]
impl SpecifiedValueInfo for ::url::Url {}
impl<T: SpecifiedValueInfo + ?Sized> SpecifiedValueInfo for Box<T> {
const SUPPORTED_TYPES: u8 = T::SUPPORTED_TYPES;
fn collect_completion_keywords(f: KeywordsCollectFn) {
T::collect_completion_keywords(f);
}
}
impl<T: SpecifiedValueInfo> SpecifiedValueInfo for [T] {
const SUPPORTED_TYPES: u8 = T::SUPPORTED_TYPES;
fn collect_completion_keywords(f: KeywordsCollectFn) {
T::collect_completion_keywords(f);
}
}
macro_rules! impl_generic_specified_value_info {
($ty:ident<$param:ident>) => {
impl<$param: SpecifiedValueInfo> SpecifiedValueInfo for $ty<$param> {
const SUPPORTED_TYPES: u8 = $param::SUPPORTED_TYPES;
fn collect_completion_keywords(f: KeywordsCollectFn) {
$param::collect_completion_keywords(f);
}
}
};
}
impl_generic_specified_value_info!(Option<T>);
impl_generic_specified_value_info!(OwnedSlice<T>);
impl_generic_specified_value_info!(Vec<T>);
impl_generic_specified_value_info!(ThinVec<T>);
impl_generic_specified_value_info!(Arc<T>);
impl_generic_specified_value_info!(StdArc<T>);
impl_generic_specified_value_info!(ArcSlice<T>);
impl_generic_specified_value_info!(Range<Idx>);
impl<T1, T2> SpecifiedValueInfo for (T1, T2)
where
T1: SpecifiedValueInfo,
T2: SpecifiedValueInfo,
{
const SUPPORTED_TYPES: u8 = T1::SUPPORTED_TYPES | T2::SUPPORTED_TYPES;
fn collect_completion_keywords(f: KeywordsCollectFn) {
T1::collect_completion_keywords(f);
T2::collect_completion_keywords(f);
}
}
