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|
use std::{
collections::BTreeMap,
fs,
io::Write,
path::Path,
process::{Command, Stdio},
};
use heck::{ShoutySnakeCase, SnakeCase};
use quote::{format_ident, quote};
use ron;
use serde::Deserialize;
use crate::{project_root, Mode, Result, AST, GRAMMAR, SYNTAX_KINDS};
pub fn generate(mode: Mode) -> Result<()> {
let grammar = project_root().join(GRAMMAR);
let grammar: Grammar = {
let text = fs::read_to_string(grammar)?;
ron::de::from_str(&text)?
};
let _syntax_kinds = project_root().join(SYNTAX_KINDS);
let _ast = project_root().join(AST);
let ast = generate_ast(&grammar)?;
println!("{}", ast);
Ok(())
}
fn generate_ast(grammar: &Grammar) -> Result<String> {
let nodes = grammar.ast.iter().map(|(name, ast_node)| {
let variants =
ast_node.variants.iter().map(|var| format_ident!("{}", var)).collect::<Vec<_>>();
let name = format_ident!("{}", name);
let kinds = if variants.is_empty() { vec![name.clone()] } else { variants.clone() }
.into_iter()
.map(|name| format_ident!("{}", name.to_string().to_shouty_snake_case()))
.collect::<Vec<_>>();
let variants = if variants.is_empty() {
None
} else {
let kind_enum = format_ident!("{}Kind", name);
Some(quote!(
pub enum #kind_enum {
#(#variants(#variants),)*
}
#(
impl From<#variants> for #name {
fn from(node: #variants) -> #name {
#name { syntax: node.syntax }
}
}
)*
impl #name {
pub fn kind(&self) -> #kind_enum {
let syntax = self.syntax.clone();
match syntax.kind() {
#(
#kinds =>
#kind_enum::#variants(#variants { syntax }),
)*
_ => unreachable!(),
}
}
}
))
};
let traits = ast_node.traits.iter().map(|trait_name| {
let trait_name = format_ident!("{}", trait_name);
quote!(impl ast::#trait_name for #name {})
});
let collections = ast_node.collections.iter().map(|(name, kind)| {
let method_name = format_ident!("{}", name);
let kind = format_ident!("{}", kind);
quote! {
pub fn #method_name(&self) -> AstChildren<#kind> {
AstChildren::new(&self.syntax)
}
}
});
let options = ast_node.options.iter().map(|attr| {
let method_name = match attr {
Attr::Type(t) => format_ident!("{}", t.to_snake_case()),
Attr::NameType(n, _) => format_ident!("{}", n),
};
let ty = match attr {
Attr::Type(t) | Attr::NameType(_, t) => format_ident!("{}", t),
};
quote! {
pub fn #method_name(&self) -> Option<#ty> {
AstChildren::new(&self.syntax).next()
}
}
});
quote! {
#[derive(Debug, Clone, PartialEq, Eq, Hash)]
pub struct #name {
pub(crate) syntax: SyntaxNode,
}
impl AstNode for #name {
fn can_cast(kind: SyntaxKind) -> bool {
match kind {
#(#kinds)|* => true,
_ => false,
}
}
fn cast(syntax: SyntaxNode) -> Option<Self> {
if Self::can_cast(syntax.kind()) { Some(Self { syntax }) } else { None }
}
fn syntax(&self) -> &SyntaxNode { &self.syntax }
}
#variants
#(#traits)*
impl #name {
#(#collections)*
#(#options)*
}
}
});
let ast = quote! {
use crate::{
SyntaxNode, SyntaxKind::{self, *},
ast::{self, AstNode, AstChildren},
};
#(#nodes)*
};
let pretty = reformat(ast)?;
Ok(pretty)
}
fn reformat(text: impl std::fmt::Display) -> Result<String> {
let mut rustfmt = Command::new("rustfmt")
.arg("--config-path")
.arg(project_root().join("rustfmt.toml"))
.stdin(Stdio::piped())
.stdout(Stdio::piped())
.spawn()?;
write!(rustfmt.stdin.take().unwrap(), "{}", text)?;
let output = rustfmt.wait_with_output()?;
let stdout = String::from_utf8(output.stdout)?;
Ok(stdout)
}
#[derive(Deserialize, Debug)]
struct Grammar {
single_byte_tokens: Vec<(String, String)>,
multi_byte_tokens: Vec<(String, String)>,
keywords: Vec<String>,
contextual_keywords: Vec<String>,
literals: Vec<String>,
tokens: Vec<String>,
ast: BTreeMap<String, AstNode>,
}
#[derive(Deserialize, Debug)]
struct AstNode {
#[serde(default)]
#[serde(rename = "enum")]
variants: Vec<String>,
#[serde(default)]
traits: Vec<String>,
#[serde(default)]
collections: Vec<(String, String)>,
#[serde(default)]
options: Vec<Attr>,
}
#[derive(Deserialize, Debug)]
#[serde(untagged)]
enum Attr {
Type(String),
NameType(String, String),
}
|
