Initial parser rewrite start
This commit is contained in:
parent
323a38db3a
commit
84c4d9d484
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@ -2,30 +2,46 @@ use core::fmt::Write;
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use crate::Value;
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use super::parse::{Ast, AstKind, For, Has, If, Print, ValuePath};
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use super::parse::{Ast, AstArena, AstNodeKind, For, Has, If, Path, Print};
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pub fn execute(ast: &Ast, value: &dyn Value) -> String {
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let mut out = String::new();
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execute_(&mut out, ast, value);
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let nodes = ast.arena.deref_many(ast.root);
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execute_(&mut out, nodes, value, &ast.arena);
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out
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}
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pub fn execute_(out: &mut String, ast: &Ast, value: &dyn Value) {
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for node in ast {
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match node {
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AstKind::Text(t) => out.push_str(&t),
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AstKind::Print(p) => print(out, p, value),
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AstKind::For(f) => for_(out, f, value),
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AstKind::Has(h) => has(out, h, value),
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AstKind::If(h) => if_(out, h, value),
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pub fn execute_(
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out: &mut String,
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nodes: &[AstNodeKind],
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value: &dyn Value,
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arena: &AstArena,
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) {
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for node in nodes {
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execute_one(out, node, value, arena)
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}
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}
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pub fn execute_one(
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out: &mut String,
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node: &AstNodeKind,
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value: &dyn Value,
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arena: &AstArena,
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) {
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match node {
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AstNodeKind::Text(t) => out.push_str(&t),
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AstNodeKind::Print(p) => print(out, p, value),
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AstNodeKind::For(f) => for_(out, f, value, arena),
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AstNodeKind::Has(h) => has(out, h, value, arena),
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AstNodeKind::With(_) => todo!(),
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AstNodeKind::If(h) => if_(out, h, value, arena),
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}
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}
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pub fn lookup<'a>(
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out: &mut String,
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path: &ValuePath,
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path: &Path,
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value: &'a dyn Value,
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) -> Option<&'a dyn Value> {
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let mut value = value;
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@ -44,7 +60,7 @@ pub fn lookup<'a>(
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}
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pub fn print(out: &mut String, p: &Print, value: &dyn Value) {
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let value = match lookup(out, &p.0, value) {
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let value = match lookup(out, &p.path, value) {
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Some(v) => v,
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None => return,
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};
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@ -52,39 +68,43 @@ pub fn print(out: &mut String, p: &Print, value: &dyn Value) {
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value.print(out)
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}
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pub fn for_(out: &mut String, f: &For, value: &dyn Value) {
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let value = match lookup(out, &f.expr, value) {
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pub fn for_(out: &mut String, f: &For, value: &dyn Value, arena: &AstArena) {
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let value = match lookup(out, &f.path, value) {
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Some(v) => v,
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None => return,
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};
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let mut idx = 0;
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while let Some(value) = value.for_(idx) {
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execute_(out, &f.body, value);
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let nodes = arena.deref_many(f.body);
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execute_(out, nodes, value, arena);
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idx += 1;
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}
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}
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pub fn has(out: &mut String, f: &Has, value: &dyn Value) {
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let value = match lookup(out, &f.expr, value) {
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pub fn has(out: &mut String, f: &Has, value: &dyn Value, arena: &AstArena) {
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let value = match lookup(out, &f.path, value) {
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Some(v) => v,
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None => return,
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};
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if let Some(value) = value.has() {
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execute_(out, &f.body, value);
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let nodes = arena.deref_many(f.body);
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execute_(out, nodes, value, arena);
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}
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}
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pub fn if_(out: &mut String, f: &If, value: &dyn Value) {
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let value = match lookup(out, &f.expr, value) {
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pub fn if_(out: &mut String, f: &If, value: &dyn Value, arena: &AstArena) {
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let value = match lookup(out, &f.path, value) {
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Some(v) => v,
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None => return,
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};
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if value.if_() {
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execute_(out, &f.then, value);
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} else if let Some(else_) = f.else_.as_ref() {
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execute_(out, else_, value);
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let nodes = arena.deref_many(f.then);
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execute_(out, nodes, value, arena);
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} else if let Some(else_) = f.else_ {
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let nodes = arena.deref_many(else_);
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execute_(out, nodes, value, arena);
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}
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}
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@ -1,390 +1,479 @@
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#[derive(Debug, PartialEq, Eq, Hash, PartialOrd, Ord)]
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pub struct ValuePath(pub Vec<String>);
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use std::ops::ControlFlow;
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pub type Expr = ValuePath;
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#[derive(Debug, PartialEq, Eq, Hash, PartialOrd, Ord)]
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pub struct If {
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pub expr: Expr,
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pub then: Ast,
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pub else_: Option<Ast>,
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#[derive(Debug, Eq, PartialEq)]
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pub struct AstArena(Vec<AstNodeKind>);
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impl AstArena {
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pub const fn new() -> Self {
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Self(Vec::new())
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}
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#[derive(Debug, PartialEq, Eq, Hash, PartialOrd, Ord)]
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pub struct For {
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pub expr: Expr,
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pub body: Ast,
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pub fn next_id(&self) -> AstNodeRef {
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AstNodeRef(
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self.0
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.len()
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.try_into()
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.expect("Tried to store too many AST nodes"),
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)
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}
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#[derive(Debug, PartialEq, Eq, Hash, PartialOrd, Ord)]
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pub struct Has {
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pub expr: Expr,
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pub body: Ast,
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pub fn add(&mut self, n: AstNodeKind) -> AstNodeRef {
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let id = self.next_id();
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self.0.push(n);
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id
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}
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#[derive(Debug, PartialEq, Eq, Hash, PartialOrd, Ord)]
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pub struct Print(pub Expr);
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pub fn add_many(&mut self, mut many: Vec<AstNodeKind>) -> AstMany {
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let start = self.next_id();
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let end = AstNodeRef(
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(start.0 as usize + many.len())
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.try_into()
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.expect("Tried to store too many AST nodes"),
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);
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self.0.append(&mut many);
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#[derive(Debug, PartialEq, Eq, Hash, PartialOrd, Ord)]
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pub enum AstKind {
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Text(String),
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Print(Print),
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Has(Has),
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AstMany { start, end }
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}
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pub fn deref(&self, rf: AstNodeRef) -> &AstNodeKind {
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&self.0[rf.0 as usize]
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}
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pub fn deref_many(&self, rf: AstMany) -> &[AstNodeKind] {
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&self.0[rf.start.0 as usize..rf.end.0 as usize]
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}
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}
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#[derive(Debug, PartialEq, Eq, Hash, PartialOrd, Ord, Copy, Clone)]
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pub struct AstNodeRef(u32);
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#[derive(Debug, PartialEq, Eq, Hash)]
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pub enum AstNodeKind {
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If(If),
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For(For),
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Has(Has),
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With(With),
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Print(Print),
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Text(String),
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}
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pub type Ast = Vec<AstKind>;
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pub struct ParseState<'a> {
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template: &'a str,
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last_byte_offset: usize,
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speculative_text_starts_at: usize,
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speculative_text_ends_at: usize,
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current_byte_offset: usize,
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ast: Ast,
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}
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impl<'a> ParseState<'a> {
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pub fn out_of_input(&self) -> bool {
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self.current_byte_offset >= self.last_byte_offset
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#[derive(Debug, PartialEq, Eq, Hash, PartialOrd, Ord, Copy, Clone)]
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pub struct AstMany {
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start: AstNodeRef,
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end: AstNodeRef,
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}
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pub fn has_input(&self) -> bool {
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!self.out_of_input()
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#[derive(Debug, PartialEq, Eq, Hash, PartialOrd, Ord)]
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pub struct Path(pub Vec<String>);
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#[derive(Debug, PartialEq, Eq, Hash)]
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pub struct If {
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pub path: Path,
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pub then: AstMany,
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pub else_: Option<AstMany>,
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}
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#[derive(Debug, PartialEq, Eq, Hash)]
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pub struct For {
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pub path: Path,
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pub body: AstMany,
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}
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#[derive(Debug, PartialEq, Eq, Hash)]
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pub struct Has {
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pub path: Path,
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pub body: AstMany,
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}
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#[derive(Debug, PartialEq, Eq, Hash)]
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pub struct With {
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pub path: Path,
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pub body: AstMany,
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}
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#[derive(Debug, PartialEq, Eq, Hash)]
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pub struct Print {
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pub path: Path,
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}
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pub struct Ast {
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pub arena: AstArena,
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pub root: AstMany,
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}
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pub struct ParseCtx<'a> {
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pub source: &'a str,
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pub current_byte_offset: usize,
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pub arena: AstArena,
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}
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impl<'a> ParseCtx<'a> {
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pub fn new(source: &'a str) -> Self {
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Self {
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source,
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current_byte_offset: 0,
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arena: AstArena::new(),
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}
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}
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pub fn loop_expecting_progress<T>(
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&mut self,
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mut inner: impl FnMut(&mut Self) -> ControlFlow<T>,
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) -> T {
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loop {
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let start = self.current_byte_offset;
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let cf = inner(self);
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match cf {
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ControlFlow::Continue(_) => {
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if self.current_byte_offset == start {
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panic!("Parser didn't make progress");
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}
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continue;
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},
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ControlFlow::Break(v) => break v,
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}
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}
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}
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pub fn at_eof(&self) -> bool {
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self.current_byte_offset >= self.source.len()
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}
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pub fn current(&self) -> char {
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self.source[self.current_byte_offset..]
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.chars()
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.next()
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.unwrap()
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}
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pub fn remaining(&self) -> &str {
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&self.template[self.current_byte_offset..]
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&self.source[self.current_byte_offset..]
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}
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pub fn add_current_text_to_ast(&mut self) {
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let text = &self.template
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[self.speculative_text_starts_at..self.speculative_text_ends_at];
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if text.is_empty() {
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return;
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pub fn looking_at(&self, ch: char) -> bool {
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!self.at_eof() && self.current() == ch
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}
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self.ast.push(AstKind::Text(
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self.template[self.speculative_text_starts_at
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..self.speculative_text_ends_at]
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.to_string(),
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));
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pub fn forward(&mut self) {
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self.current_byte_offset += self.current().len_utf8()
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}
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pub fn text_might_end(&mut self) {
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self.speculative_text_ends_at = self.current_byte_offset;
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pub fn forward_str(&mut self, str: &str) {
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self.current_byte_offset += str.len()
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}
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pub fn parse(&mut self) {
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while self.has_input() {
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self.parse_one();
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pub fn scan_until(&mut self, ch: char) {
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self.loop_expecting_progress(|s| {
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if s.at_eof() {
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return ControlFlow::Break(());
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}
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self.text_might_end();
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self.add_current_text_to_ast();
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let current = s.current();
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if current == ch {
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return ControlFlow::Break(());
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}
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s.current_byte_offset += current.len_utf8();
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pub fn parse_one(&mut self) {
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assert!(self.has_input());
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let started_at = self.current_byte_offset;
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if self.remaining().starts_with('{') {
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self.text_might_end();
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self.maybe_parse_block();
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} else {
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self.current_byte_offset += 1;
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}
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if started_at == self.current_byte_offset {
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panic!("Parser made no progress");
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}
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}
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pub fn maybe_parse_block(&mut self) {
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assert!(self.remaining().starts_with('{'));
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self.current_byte_offset += 1;
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self.skip_whitespace();
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let remaining = self.remaining();
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if remaining.starts_with('.') {
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self.maybe_parse_print();
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} else if remaining.starts_with("for") {
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self.maybe_parse_for();
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} else if remaining.starts_with("has") {
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self.maybe_parse_has();
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} else if remaining.starts_with("if") {
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self.maybe_parse_if();
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}
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}
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pub fn maybe_parse_print(&mut self) {
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assert!(self.remaining().starts_with('.'));
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let path = match self.parse_path() {
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None => return,
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Some(vp) => vp,
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};
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self.skip_whitespace();
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if !self.remaining().starts_with('}') {
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return;
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}
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self.current_byte_offset += 1;
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self.push_node_and_text(AstKind::Print(Print(path)));
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self.new_empty_text();
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}
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pub fn maybe_parse_for(&mut self) {
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assert!(self.remaining().starts_with("for"));
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self.current_byte_offset += "for".len();
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self.skip_whitespace();
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let path = match self.parse_path() {
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None => return,
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Some(vp) => vp,
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};
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self.skip_whitespace();
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if !self.remaining().starts_with('}') {
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return;
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}
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self.current_byte_offset += 1;
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let mut inner = ParseState {
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template: self.template,
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last_byte_offset: self.last_byte_offset,
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speculative_text_starts_at: self.current_byte_offset,
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speculative_text_ends_at: self.current_byte_offset,
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current_byte_offset: self.current_byte_offset,
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ast: Ast::new(),
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};
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while inner.has_input() {
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if inner.remaining().starts_with("{/for}") {
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break;
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}
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inner.parse_one();
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}
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inner.text_might_end();
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inner.add_current_text_to_ast();
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self.current_byte_offset = inner.current_byte_offset;
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if !self.remaining().starts_with("{/for}") {
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return;
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}
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self.current_byte_offset += "{/for}".len();
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let body = inner.ast;
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self.push_node_and_text(AstKind::For(For { expr: path, body }));
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self.new_empty_text();
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}
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pub fn maybe_parse_has(&mut self) {
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assert!(self.remaining().starts_with("has"));
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self.current_byte_offset += "has".len();
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self.skip_whitespace();
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let path = match self.parse_path() {
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None => return,
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Some(vp) => vp,
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};
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self.skip_whitespace();
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if !self.remaining().starts_with('}') {
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return;
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}
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self.current_byte_offset += 1;
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let mut inner = ParseState {
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template: self.template,
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last_byte_offset: self.last_byte_offset,
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speculative_text_starts_at: self.current_byte_offset,
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speculative_text_ends_at: self.current_byte_offset,
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current_byte_offset: self.current_byte_offset,
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ast: Ast::new(),
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};
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while inner.has_input() {
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if inner.remaining().starts_with("{/has}") {
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break;
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}
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inner.parse_one();
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}
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inner.text_might_end();
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inner.add_current_text_to_ast();
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self.current_byte_offset = inner.current_byte_offset;
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if !self.remaining().starts_with("{/has}") {
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return;
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}
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self.current_byte_offset += "{/has}".len();
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let body = inner.ast;
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self.push_node_and_text(AstKind::Has(Has { expr: path, body }));
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self.new_empty_text();
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}
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pub fn maybe_parse_if(&mut self) {
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assert!(self.remaining().starts_with("if"));
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self.current_byte_offset += "if".len();
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self.skip_whitespace();
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let path = match self.parse_path() {
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None => return,
|
||||
Some(vp) => vp,
|
||||
};
|
||||
self.skip_whitespace();
|
||||
if !self.remaining().starts_with('}') {
|
||||
return;
|
||||
}
|
||||
self.current_byte_offset += 1;
|
||||
|
||||
let mut inner = ParseState {
|
||||
template: self.template,
|
||||
last_byte_offset: self.last_byte_offset,
|
||||
speculative_text_starts_at: self.current_byte_offset,
|
||||
speculative_text_ends_at: self.current_byte_offset,
|
||||
current_byte_offset: self.current_byte_offset,
|
||||
ast: Ast::new(),
|
||||
};
|
||||
while inner.has_input() {
|
||||
if inner.remaining().starts_with("{/if}") {
|
||||
break;
|
||||
}
|
||||
if inner.remaining().starts_with("{else}") {
|
||||
break;
|
||||
}
|
||||
inner.parse_one();
|
||||
}
|
||||
inner.text_might_end();
|
||||
inner.add_current_text_to_ast();
|
||||
self.current_byte_offset = inner.current_byte_offset;
|
||||
|
||||
let else_ = if self.remaining().starts_with("{else}") {
|
||||
self.current_byte_offset += "{else}".len();
|
||||
let mut inner = ParseState {
|
||||
template: self.template,
|
||||
last_byte_offset: self.last_byte_offset,
|
||||
speculative_text_starts_at: self.current_byte_offset,
|
||||
speculative_text_ends_at: self.current_byte_offset,
|
||||
current_byte_offset: self.current_byte_offset,
|
||||
ast: Ast::new(),
|
||||
};
|
||||
while inner.has_input() {
|
||||
if inner.remaining().starts_with("{/if}") {
|
||||
break;
|
||||
}
|
||||
inner.parse_one();
|
||||
}
|
||||
inner.text_might_end();
|
||||
inner.add_current_text_to_ast();
|
||||
self.current_byte_offset = inner.current_byte_offset;
|
||||
Some(inner.ast)
|
||||
} else {
|
||||
None
|
||||
};
|
||||
if !self.remaining().starts_with("{/if}") {
|
||||
return;
|
||||
}
|
||||
self.current_byte_offset += "{/if}".len();
|
||||
let body = inner.ast;
|
||||
|
||||
self.push_node_and_text(AstKind::If(If {
|
||||
expr: path,
|
||||
then: body,
|
||||
else_,
|
||||
}));
|
||||
self.new_empty_text();
|
||||
}
|
||||
|
||||
pub fn parse_path(&mut self) -> Option<ValuePath> {
|
||||
assert!(self.remaining().starts_with('.'));
|
||||
self.current_byte_offset += 1;
|
||||
let end = self
|
||||
.remaining()
|
||||
.find(|ch: char| ch == '}' || ch.is_whitespace())
|
||||
.unwrap_or(self.last_byte_offset - self.current_byte_offset);
|
||||
let inner = &self.remaining()[..end];
|
||||
let out = inner.split_terminator('.').map(|s| s.to_string()).collect();
|
||||
let out = ValuePath(out);
|
||||
|
||||
self.current_byte_offset += end;
|
||||
|
||||
Some(out)
|
||||
}
|
||||
|
||||
pub fn push_node_and_text(&mut self, node: AstKind) {
|
||||
self.add_current_text_to_ast();
|
||||
self.ast.push(node);
|
||||
}
|
||||
|
||||
pub fn new_empty_text(&mut self) {
|
||||
self.speculative_text_starts_at = self.current_byte_offset;
|
||||
self.speculative_text_ends_at = self.speculative_text_starts_at;
|
||||
ControlFlow::Continue(())
|
||||
})
|
||||
}
|
||||
|
||||
pub fn skip_whitespace(&mut self) {
|
||||
while self.has_input() {
|
||||
if self.remaining().starts_with(char::is_whitespace) {
|
||||
self.current_byte_offset +=
|
||||
self.remaining().chars().next().unwrap().len_utf8();
|
||||
continue;
|
||||
self.loop_expecting_progress(|s| {
|
||||
if s.at_eof() {
|
||||
return ControlFlow::Break(());
|
||||
}
|
||||
break;
|
||||
|
||||
let current = s.current();
|
||||
if !current.is_whitespace() {
|
||||
return ControlFlow::Break(());
|
||||
}
|
||||
s.current_byte_offset += current.len_utf8();
|
||||
|
||||
ControlFlow::Continue(())
|
||||
})
|
||||
}
|
||||
|
||||
pub fn parse_until(
|
||||
&mut self,
|
||||
mut f: impl FnMut(&mut Self) -> bool,
|
||||
) -> Option<AstMany> {
|
||||
let mut out = Vec::new();
|
||||
let missing_terminator = self.loop_expecting_progress(|s| {
|
||||
if f(s) {
|
||||
return ControlFlow::Break(false);
|
||||
}
|
||||
|
||||
if s.at_eof() {
|
||||
return ControlFlow::Break(true);
|
||||
}
|
||||
|
||||
let (text, trailing) = s.parse_text_with_trailing();
|
||||
if let Some(text) = text {
|
||||
out.push(AstNodeKind::Text(text));
|
||||
}
|
||||
if let Some(block) = trailing {
|
||||
out.push(block);
|
||||
}
|
||||
|
||||
ControlFlow::Continue(())
|
||||
});
|
||||
|
||||
if missing_terminator {
|
||||
None
|
||||
} else {
|
||||
Some(self.arena.add_many(out))
|
||||
}
|
||||
}
|
||||
|
||||
pub fn parse(template: &str) -> Ast {
|
||||
let mut state = ParseState {
|
||||
template,
|
||||
speculative_text_starts_at: 0,
|
||||
speculative_text_ends_at: 0,
|
||||
current_byte_offset: 0,
|
||||
last_byte_offset: template.len(),
|
||||
ast: Ast::new(),
|
||||
pub fn parse_text_with_trailing(
|
||||
&mut self,
|
||||
) -> (Option<String>, Option<AstNodeKind>) {
|
||||
let text_starts_at = self.current_byte_offset;
|
||||
|
||||
let (text, trailing) = self.loop_expecting_progress(|s| {
|
||||
s.scan_until('{');
|
||||
if s.at_eof() {
|
||||
return ControlFlow::Break((&s.source[text_starts_at..], None));
|
||||
}
|
||||
|
||||
let text_maybe_ends_at = s.current_byte_offset;
|
||||
if let Some(block) = s.parse_block() {
|
||||
return ControlFlow::Break((
|
||||
&s.source[text_starts_at..text_maybe_ends_at],
|
||||
Some(block),
|
||||
));
|
||||
}
|
||||
|
||||
ControlFlow::Continue(())
|
||||
});
|
||||
|
||||
let text = if text.is_empty() {
|
||||
None
|
||||
} else {
|
||||
Some(text.to_string())
|
||||
};
|
||||
state.parse();
|
||||
|
||||
state.ast
|
||||
(text, trailing)
|
||||
}
|
||||
|
||||
pub fn parse_block(&mut self) -> Option<AstNodeKind> {
|
||||
if !self.looking_at('{') {
|
||||
return None;
|
||||
}
|
||||
self.forward();
|
||||
|
||||
self.skip_whitespace();
|
||||
let remaining = self.remaining();
|
||||
if remaining.starts_with(".") {
|
||||
self.parse_print().map(AstNodeKind::Print)
|
||||
} else if remaining.starts_with("for") {
|
||||
self.parse_for().map(AstNodeKind::For)
|
||||
} else if remaining.starts_with("has") {
|
||||
self.parse_has().map(AstNodeKind::Has)
|
||||
} else if remaining.starts_with("if") {
|
||||
self.parse_if().map(AstNodeKind::If)
|
||||
} else if remaining.starts_with("with") {
|
||||
self.parse_with().map(AstNodeKind::With)
|
||||
} else {
|
||||
None
|
||||
}
|
||||
}
|
||||
|
||||
pub fn parse_path(&mut self) -> Option<Path> {
|
||||
let mut out = Vec::new();
|
||||
if !self.looking_at('.') {
|
||||
return None;
|
||||
}
|
||||
self.forward();
|
||||
|
||||
self.loop_expecting_progress(|s| {
|
||||
let start = s.current_byte_offset;
|
||||
s.loop_expecting_progress(|s| {
|
||||
if s.current().is_whitespace()
|
||||
|| s.current() == '}'
|
||||
|| s.current() == '.'
|
||||
{
|
||||
return ControlFlow::Break(());
|
||||
}
|
||||
s.forward();
|
||||
|
||||
ControlFlow::Continue(())
|
||||
});
|
||||
let end = s.current_byte_offset;
|
||||
let str = &s.source[start..end];
|
||||
if str.is_empty() {
|
||||
return ControlFlow::Break(());
|
||||
}
|
||||
out.push(str.to_string());
|
||||
|
||||
if !s.looking_at('.') {
|
||||
return ControlFlow::Break(());
|
||||
}
|
||||
s.forward();
|
||||
ControlFlow::Continue(())
|
||||
});
|
||||
|
||||
Some(Path(out))
|
||||
}
|
||||
|
||||
pub fn parse_print(&mut self) -> Option<Print> {
|
||||
let path = self.parse_path()?;
|
||||
self.skip_whitespace();
|
||||
if !self.looking_at('}') {
|
||||
return None;
|
||||
}
|
||||
self.forward();
|
||||
|
||||
Some(Print { path })
|
||||
}
|
||||
|
||||
pub fn parse_if(&mut self) -> Option<If> {
|
||||
if !self.remaining().starts_with("if") {
|
||||
return None;
|
||||
}
|
||||
self.forward_str("for");
|
||||
self.skip_whitespace();
|
||||
let path = self.parse_path()?;
|
||||
self.skip_whitespace();
|
||||
if !self.looking_at('}') {
|
||||
return None;
|
||||
}
|
||||
self.forward();
|
||||
|
||||
let then = self.parse_until(|s| {
|
||||
s.remaining().starts_with("{/if}")
|
||||
|| s.remaining().starts_with("{else}")
|
||||
})?;
|
||||
if self.remaining().starts_with("{/if}") {
|
||||
self.forward_str("{/if}");
|
||||
|
||||
return Some(If {
|
||||
path,
|
||||
then,
|
||||
else_: None,
|
||||
});
|
||||
}
|
||||
self.forward_str("{else}");
|
||||
let else_ = self.parse_until(|s| s.remaining().starts_with("{/if}"))?;
|
||||
self.forward_str("{/if}");
|
||||
|
||||
Some(If {
|
||||
path,
|
||||
then,
|
||||
else_: Some(else_),
|
||||
})
|
||||
}
|
||||
|
||||
pub fn parse_for(&mut self) -> Option<For> {
|
||||
if !self.remaining().starts_with("for") {
|
||||
return None;
|
||||
}
|
||||
self.forward_str("for");
|
||||
self.skip_whitespace();
|
||||
let path = self.parse_path()?;
|
||||
self.skip_whitespace();
|
||||
if !self.looking_at('}') {
|
||||
return None;
|
||||
}
|
||||
self.forward();
|
||||
|
||||
let many = self.parse_until(|s| s.remaining().starts_with("{/for}"))?;
|
||||
self.forward_str("{/for}");
|
||||
|
||||
Some(For { path, body: many })
|
||||
}
|
||||
|
||||
pub fn parse_with(&mut self) -> Option<With> {
|
||||
if !self.remaining().starts_with("with") {
|
||||
return None;
|
||||
}
|
||||
self.forward_str("with");
|
||||
self.skip_whitespace();
|
||||
let path = self.parse_path()?;
|
||||
self.skip_whitespace();
|
||||
if !self.looking_at('}') {
|
||||
return None;
|
||||
}
|
||||
self.forward();
|
||||
|
||||
let many =
|
||||
self.parse_until(|s| s.remaining().starts_with("{/with}"))?;
|
||||
self.forward_str("{/with}");
|
||||
|
||||
Some(With { path, body: many })
|
||||
}
|
||||
|
||||
pub fn parse_has(&mut self) -> Option<Has> {
|
||||
if !self.remaining().starts_with("has") {
|
||||
return None;
|
||||
}
|
||||
self.forward_str("has");
|
||||
self.skip_whitespace();
|
||||
let path = self.parse_path()?;
|
||||
self.skip_whitespace();
|
||||
if !self.looking_at('}') {
|
||||
return None;
|
||||
}
|
||||
self.forward();
|
||||
|
||||
let many = self.parse_until(|s| s.remaining().starts_with("{/has}"))?;
|
||||
self.forward_str("{/has}");
|
||||
|
||||
Some(Has { path, body: many })
|
||||
}
|
||||
}
|
||||
|
||||
pub fn parse(source: &str) -> Ast {
|
||||
let mut ctx = ParseCtx::new(source);
|
||||
let root = ctx.parse_until(|ctx| ctx.at_eof()).unwrap();
|
||||
|
||||
Ast {
|
||||
arena: ctx.arena,
|
||||
root,
|
||||
}
|
||||
}
|
||||
|
||||
#[cfg(test)]
|
||||
mod test {
|
||||
use crate::internal::parse::{AstKind, Print, ValuePath};
|
||||
use super::{
|
||||
parse, AstMany, AstNodeKind, AstNodeRef, For, Has, If, Path, Print,
|
||||
};
|
||||
|
||||
use super::{parse, Ast, For, Has, If};
|
||||
|
||||
fn go(tmpl: &str, rhs: Ast) {
|
||||
let ast = parse(tmpl);
|
||||
assert_eq!(ast, rhs);
|
||||
fn go(input: &str, expected: Vec<AstNodeKind>) {
|
||||
assert_eq!(parse(input).arena.0, expected)
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn parse_print_only() {
|
||||
go("{.}", vec![AstKind::Print(Print(ValuePath(vec![])))]);
|
||||
fn parse_text() {
|
||||
go(
|
||||
"Hello, world!",
|
||||
vec![AstNodeKind::Text("Hello, world!".to_string())],
|
||||
)
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn parse_print() {
|
||||
go(
|
||||
"hello, {.}!",
|
||||
vec![
|
||||
AstKind::Text("hello, ".to_string()),
|
||||
AstKind::Print(Print(ValuePath(vec![]))),
|
||||
AstKind::Text("!".to_string()),
|
||||
],
|
||||
"{ .test }",
|
||||
vec![AstNodeKind::Print(Print {
|
||||
path: Path(vec!["test".to_string()]),
|
||||
})],
|
||||
);
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn parse_print_lookup() {
|
||||
fn parse_print_just_dot() {
|
||||
go(
|
||||
"hello, {.name}!",
|
||||
vec![
|
||||
AstKind::Text("hello, ".to_string()),
|
||||
AstKind::Print(Print(ValuePath(vec!["name".to_string()]))),
|
||||
AstKind::Text("!".to_string()),
|
||||
],
|
||||
"{ . }",
|
||||
vec![AstNodeKind::Print(Print { path: Path(vec![]) })],
|
||||
);
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn parse_for() {
|
||||
fn parse_print_nested_path() {
|
||||
go(
|
||||
"{for .}{.}{/for}",
|
||||
vec![AstKind::For(For {
|
||||
expr: ValuePath(vec![]),
|
||||
body: vec![AstKind::Print(Print(ValuePath(vec![])))],
|
||||
"{ .foo.bar }",
|
||||
vec![AstNodeKind::Print(Print {
|
||||
path: Path(vec!["foo".to_string(), "bar".to_string()]),
|
||||
})],
|
||||
);
|
||||
}
|
||||
|
|
@ -392,66 +481,76 @@ mod test {
|
|||
#[test]
|
||||
fn parse_has() {
|
||||
go(
|
||||
"{has .}{.}{/has}",
|
||||
vec![AstKind::Has(Has {
|
||||
expr: ValuePath(vec![]),
|
||||
body: vec![AstKind::Print(Print(ValuePath(vec![])))],
|
||||
})],
|
||||
"{ has .test }{.}{/has}",
|
||||
vec![
|
||||
AstNodeKind::Print(Print { path: Path(vec![]) }),
|
||||
AstNodeKind::Has(Has {
|
||||
path: Path(vec!["test".to_string()]),
|
||||
body: AstMany {
|
||||
start: AstNodeRef(0),
|
||||
end: AstNodeRef(1),
|
||||
},
|
||||
}),
|
||||
],
|
||||
);
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn parse_for() {
|
||||
go(
|
||||
"{ for .test }{.}{/for}",
|
||||
vec![
|
||||
AstNodeKind::Print(Print { path: Path(vec![]) }),
|
||||
AstNodeKind::For(For {
|
||||
path: Path(vec!["test".to_string()]),
|
||||
body: AstMany {
|
||||
start: AstNodeRef(0),
|
||||
end: AstNodeRef(1),
|
||||
},
|
||||
}),
|
||||
],
|
||||
);
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn parse_if() {
|
||||
go(
|
||||
"{if .}{.}{/if}",
|
||||
vec![AstKind::If(If {
|
||||
expr: ValuePath(vec![]),
|
||||
then: vec![AstKind::Print(Print(ValuePath(vec![])))],
|
||||
"{ if .test }{.test}{/if}",
|
||||
vec![
|
||||
AstNodeKind::Print(Print {
|
||||
path: Path(vec!["test".to_string()]),
|
||||
}),
|
||||
AstNodeKind::If(If {
|
||||
path: Path(vec!["test".to_string()]),
|
||||
then: AstMany {
|
||||
start: AstNodeRef(0),
|
||||
end: AstNodeRef(1),
|
||||
},
|
||||
else_: None,
|
||||
})],
|
||||
}),
|
||||
],
|
||||
);
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn parse_if_else() {
|
||||
go(
|
||||
"{if .}{.}{else}Empty{/if}",
|
||||
vec![AstKind::If(If {
|
||||
expr: ValuePath(vec![]),
|
||||
then: vec![AstKind::Print(Print(ValuePath(vec![])))],
|
||||
else_: Some(vec![AstKind::Text("Empty".to_string())]),
|
||||
})],
|
||||
"{ if .test }{.test}{else}Hello{/if}",
|
||||
vec![
|
||||
AstNodeKind::Print(Print {
|
||||
path: Path(vec!["test".to_string()]),
|
||||
}),
|
||||
AstNodeKind::If(If {
|
||||
path: Path(vec!["test".to_string()]),
|
||||
then: AstMany {
|
||||
start: AstNodeRef(0),
|
||||
end: AstNodeRef(1),
|
||||
},
|
||||
else_: Some(AstMany {
|
||||
start: AstNodeRef(0),
|
||||
end: AstNodeRef(1),
|
||||
}),
|
||||
}),
|
||||
],
|
||||
);
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn parse_for_2() {
|
||||
go(
|
||||
"{for .}{.}, {/for}",
|
||||
vec![AstKind::For(For {
|
||||
expr: ValuePath(vec![]),
|
||||
body: vec![
|
||||
AstKind::Print(Print(ValuePath(vec![]))),
|
||||
AstKind::Text(", ".to_string()),
|
||||
],
|
||||
})],
|
||||
);
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn parse_for_nested() {
|
||||
go(
|
||||
"{for .items}{for .names}{.},{/for}{/for}",
|
||||
vec![AstKind::For(For {
|
||||
expr: ValuePath(vec!["items".to_string()]),
|
||||
body: vec![AstKind::For(For {
|
||||
expr: ValuePath(vec!["names".to_string()]),
|
||||
body: vec![
|
||||
AstKind::Print(Print(ValuePath(vec![]))),
|
||||
AstKind::Text(",".to_string()),
|
||||
],
|
||||
})],
|
||||
})],
|
||||
)
|
||||
}
|
||||
}
|
||||
|
|
|
|||
Loading…
Reference in a new issue