//! Tree of nodes
use syn::{punctuated::Punctuated, token::Colon, Expr, ExprPath, Ident, Lit};
use crate::punctuation::Dash;
/// Node in the tree
#[derive(Debug)]
pub struct Node {
/// Name according to the `NodeType`:
///
/// - `Element`: Name of the element
/// - `Attribute`: Key of the element attribute
/// - `Text`: `None`
/// - `Block`: `None`
pub name: Option<NodeName>,
/// Type of the nodes
pub node_type: NodeType,
/// Value according to the `NodeType`:
///
/// - `Element`: `None`
/// - `Attribute`: Any valid `syn::Expr`
/// - `Text`: `syn::Expr::Lit`
/// - `Block`: `syn::Expr::Block`
pub value: Option<Expr>,
/// Has nodes if `NodeType::Element`. Every attribute is
/// `NodeType::Attribute`
pub attributes: Vec<Node>,
/// Has nodes if `NodeType::Element`
pub children: Vec<Node>,
}
impl Node {
/// Returns `name` as `String` if it's `Some`
pub fn name_as_string(&self) -> Option<String> {
match self.name.as_ref() {
Some(NodeName::Path(expr)) => Some(
expr.path
.segments
.iter()
.map(|segment| segment.ident.to_string())
.collect::<Vec<String>>()
.join("::"),
),
Some(NodeName::Dash(name)) => Some(
name.iter()
.map(|ident| ident.to_string())
.collect::<Vec<String>>()
.join("-"),
),
Some(NodeName::Colon(name)) => Some(
name.iter()
.map(|ident| ident.to_string())
.collect::<Vec<String>>()
.join(":"),
),
None => None,
}
}
/// Returns `value` as `String` if it's a `Lit::Str` expression
pub fn value_as_string(&self) -> Option<String> {
match self.value.as_ref() {
Some(Expr::Lit(expr)) => match &expr.lit {
Lit::Str(lit_str) => Some(lit_str.value()),
_ => None,
},
_ => None,
}
}
}
/// Type of the node
#[derive(Debug)]
pub enum NodeType {
/// A HTMLElement tag, with optional children and attributes.
/// Potentially selfclosing. Any tag name is valid.
Element,
/// Attributes of opening tags. Every attribute is itself a node.
Attribute,
/// Quoted text. It's planned to support unquoted text as well
/// using span start and end, but that currently only works
/// with nightly rust
Text,
/// Arbitrary rust code in braced `{}` blocks
Block,
}
/// Name of the node
#[derive(Debug)]
pub enum NodeName {
/// [Mod style path] containing no path arguments on any of its segments. A
/// plain identifier like `x` is a path of length 1.
///
/// [Mod style path]:
/// https://docs.rs/syn/1.0.30/syn/struct.Path.html#method.parse_mod_style
Path(ExprPath),
/// Name separated by dashes, e.g. `<div data-foo="bar" />`
Dash(Punctuated<Ident, Dash>),
/// Name separated by colons, e.g. `<div on:click={foo} />`
Colon(Punctuated<Ident, Colon>),
}
impl PartialEq for NodeName {
fn eq(&self, other: &NodeName) -> bool {
match self {
Self::Path(this) => match other {
Self::Path(other) => this == other,
_ => false,
},
Self::Dash(this) => match other {
Self::Dash(other) => this == other,
_ => false,
},
Self::Colon(this) => match other {
Self::Colon(other) => this == other,
_ => false,
},
}
}
}