Move parser into askama_shared

4 files changed, 4 insertions, 1106 deletions

diff --git a/askama_derive/Cargo.toml b/askama_derive/Cargo.toml
index 799f989..8b77d12 100644
--- a/askama_derive/Cargo.toml
+++ b/askama_derive/Cargo.toml
@@ -21,9 +21,6 @@ warp = []
 
 [dependencies]
 askama_shared = { version = "0.9", path = "../askama_shared" }
-# default for features for nom don't work result in linker errors:
-# https://github.com/rust-lang/rust/issues/62146
-nom = { version = "5", default-features = false, features = ["std"] }
 proc-macro2 = "1"
 quote = "1"
 syn = "1"
diff --git a/askama_derive/src/generator.rs b/askama_derive/src/generator.rs
index ab1a012..4f5b495 100644
--- a/askama_derive/src/generator.rs
+++ b/askama_derive/src/generator.rs
@@ -1,9 +1,9 @@
 use super::{get_template_source, Context, Heritage};
 use crate::input::{Source, TemplateInput};
-use crate::parser::{
-    Cond, Expr, MatchParameter, MatchParameters, MatchVariant, Node, Target, When, WS,
-};
 use askama_shared::filters;
+use askama_shared::parser::{
+    parse, Cond, Expr, MatchParameter, MatchParameters, MatchVariant, Node, Target, When, WS,
+};
 
 use proc_macro2::Span;
 
@@ -15,8 +15,6 @@ use std::{cmp, hash, mem, str};
 
 use syn;
 
-use crate::parser::parse;
-
 pub(crate) fn generate(
     input: &TemplateInput,
     contexts: &HashMap<&PathBuf, Context>,
diff --git a/askama_derive/src/lib.rs b/askama_derive/src/lib.rs
index 97228fd..2189458 100644
--- a/askama_derive/src/lib.rs
+++ b/askama_derive/src/lib.rs
@@ -1,19 +1,15 @@
 extern crate proc_macro;
 #[macro_use]
-extern crate nom;
-#[macro_use]
 extern crate quote;
 
 mod generator;
 mod input;
-mod parser;
 
 use crate::input::{Print, Source, TemplateInput};
-use crate::parser::{Expr, Macro, Node};
+use askama_shared::parser::{parse, Expr, Macro, Node};
 use askama_shared::{read_config_file, Config};
 use proc_macro::TokenStream;
 
-use crate::parser::parse;
 use std::collections::HashMap;
 use std::fs;
 use std::path::{Path, PathBuf};
diff --git a/askama_derive/src/parser.rs b/askama_derive/src/parser.rs
deleted file mode 100644
index 910815a..0000000
--- a/askama_derive/src/parser.rs
+++ /dev/null
@@ -1,1093 +0,0 @@
-use nom::branch::alt;
-use nom::bytes::complete::{escaped, is_not, tag, take_until};
-use nom::character::complete::{anychar, char, digit1};
-use nom::combinator::{complete, map, opt};
-use nom::error::ParseError;
-use nom::multi::{many0, many1, separated_list, separated_nonempty_list};
-use nom::sequence::{delimited, pair, tuple};
-use nom::{self, Compare, IResult, InputTake};
-use std::str;
-
-use askama_shared::Syntax;
-
-#[derive(Debug)]
-pub enum Expr<'a> {
-    BoolLit(&'a str),
-    NumLit(&'a str),
-    StrLit(&'a str),
-    CharLit(&'a str),
-    Var(&'a str),
-    Path(Vec<&'a str>),
-    Array(Vec<Expr<'a>>),
-    Attr(Box<Expr<'a>>, &'a str),
-    Index(Box<Expr<'a>>, Box<Expr<'a>>),
-    Filter(&'a str, Vec<Expr<'a>>),
-    Unary(&'a str, Box<Expr<'a>>),
-    BinOp(&'a str, Box<Expr<'a>>, Box<Expr<'a>>),
-    Range(&'a str, Option<Box<Expr<'a>>>, Option<Box<Expr<'a>>>),
-    Group(Box<Expr<'a>>),
-    MethodCall(Box<Expr<'a>>, &'a str, Vec<Expr<'a>>),
-    RustMacro(&'a str, &'a str),
-}
-
-#[derive(Debug)]
-pub enum MatchVariant<'a> {
-    Path(Vec<&'a str>),
-    Name(&'a str),
-    NumLit(&'a str),
-    StrLit(&'a str),
-    CharLit(&'a str),
-}
-
-#[derive(Debug)]
-pub enum MatchParameter<'a> {
-    Name(&'a str),
-    NumLit(&'a str),
-    StrLit(&'a str),
-    CharLit(&'a str),
-}
-
-#[derive(Debug)]
-pub enum Target<'a> {
-    Name(&'a str),
-    Tuple(Vec<&'a str>),
-}
-
-#[derive(Clone, Copy, Debug)]
-pub struct WS(pub bool, pub bool);
-
-#[derive(Debug)]
-pub struct Macro<'a> {
-    pub ws1: WS,
-    pub args: Vec<&'a str>,
-    pub nodes: Vec<Node<'a>>,
-    pub ws2: WS,
-}
-
-#[derive(Debug)]
-pub enum Node<'a> {
-    Lit(&'a str, &'a str, &'a str),
-    Comment(WS),
-    Expr(WS, Expr<'a>),
-    Call(WS, Option<&'a str>, &'a str, Vec<Expr<'a>>),
-    LetDecl(WS, Target<'a>),
-    Let(WS, Target<'a>, Expr<'a>),
-    Cond(Vec<(WS, Option<Expr<'a>>, Vec<Node<'a>>)>, WS),
-    Match(WS, Expr<'a>, Option<&'a str>, Vec<When<'a>>, WS),
-    Loop(WS, Target<'a>, Expr<'a>, Vec<Node<'a>>, WS),
-    Extends(Expr<'a>),
-    BlockDef(WS, &'a str, Vec<Node<'a>>, WS),
-    Include(WS, &'a str),
-    Import(WS, &'a str, &'a str),
-    Macro(&'a str, Macro<'a>),
-    Raw(WS, &'a str, WS),
-}
-
-pub type Cond<'a> = (WS, Option<Expr<'a>>, Vec<Node<'a>>);
-pub type When<'a> = (
-    WS,
-    Option<MatchVariant<'a>>,
-    MatchParameters<'a>,
-    Vec<Node<'a>>,
-);
-
-#[derive(Debug)]
-pub enum MatchParameters<'a> {
-    Simple(Vec<MatchParameter<'a>>),
-    Named(Vec<(&'a str, Option<MatchParameter<'a>>)>),
-}
-
-impl<'a> Default for MatchParameters<'a> {
-    fn default() -> Self {
-        MatchParameters::Simple(vec![])
-    }
-}
-
-fn ws<F, I, O, E>(inner: F) -> impl Fn(I) -> IResult<I, O, E>
-where
-    F: Fn(I) -> IResult<I, O, E>,
-    I: InputTake + Clone + PartialEq + for<'a> Compare<&'a [u8; 1]>,
-    E: ParseError<I>,
-{
-    move |i: I| {
-        let i = alt::<_, _, (), _>((tag(b" "), tag(b"\t")))(i.clone())
-            .map(|(i, _)| i)
-            .unwrap_or(i);
-        let (i, res) = inner(i)?;
-        let i = alt::<_, _, (), _>((tag(b" "), tag(b"\t")))(i.clone())
-            .map(|(i, _)| i)
-            .unwrap_or(i);
-        Ok((i, res))
-    }
-}
-
-fn split_ws_parts(s: &[u8]) -> Node {
-    if s.is_empty() {
-        let rs = str::from_utf8(s).unwrap();
-        return Node::Lit(rs, rs, rs);
-    }
-
-    let is_ws = |c: &u8| *c != b' ' && *c != b'\t' && *c != b'\r' && *c != b'\n';
-    let start = s.iter().position(&is_ws);
-    let res = if let Some(start) = start {
-        let end = s.iter().rposition(&is_ws);
-        if let Some(end) = end {
-            (&s[..start], &s[start..=end], &s[end + 1..])
-        } else {
-            (&s[..start], &s[start..], &s[0..0])
-        }
-    } else {
-        (s, &s[0..0], &s[0..0])
-    };
-
-    Node::Lit(
-        str::from_utf8(res.0).unwrap(),
-        str::from_utf8(res.1).unwrap(),
-        str::from_utf8(res.2).unwrap(),
-    )
-}
-
-#[derive(Debug)]
-enum ContentState {
-    Start,
-    Any,
-    Brace(usize),
-    End(usize),
-}
-
-fn take_content<'a>(i: &'a [u8], s: &'a Syntax<'a>) -> ParserError<'a, Node<'a>> {
-    use crate::parser::ContentState::*;
-    let bs = s.block_start.as_bytes()[0];
-    let be = s.block_start.as_bytes()[1];
-    let cs = s.comment_start.as_bytes()[0];
-    let ce = s.comment_start.as_bytes()[1];
-    let es = s.expr_start.as_bytes()[0];
-    let ee = s.expr_start.as_bytes()[1];
-
-    let mut state = Start;
-    for (idx, c) in i.iter().enumerate() {
-        state = match state {
-            Start | Any => {
-                if *c == bs || *c == es || *c == cs {
-                    Brace(idx)
-                } else {
-                    Any
-                }
-            }
-            Brace(start) => {
-                if *c == be || *c == ee || *c == ce {
-                    End(start)
-                } else {
-                    Any
-                }
-            }
-            End(_) => panic!("cannot happen"),
-        };
-        if let End(_) = state {
-            break;
-        }
-    }
-
-    match state {
-        Any | Brace(_) => Ok((&i[..0], split_ws_parts(i))),
-        Start | End(0) => Err(nom::Err::Error(error_position!(
-            i,
-            nom::error::ErrorKind::TakeUntil
-        ))),
-        End(start) => Ok((&i[start..], split_ws_parts(&i[..start]))),
-    }
-}
-
-fn identifier(input: &[u8]) -> ParserError<&str> {
-    if !nom::character::is_alphabetic(input[0]) && input[0] != b'_' && !non_ascii(input[0]) {
-        return Err(nom::Err::Error(error_position!(
-            input,
-            nom::error::ErrorKind::AlphaNumeric
-        )));
-    }
-    for (i, ch) in input.iter().enumerate() {
-        if i == 0 || nom::character::is_alphanumeric(*ch) || *ch == b'_' || non_ascii(*ch) {
-            continue;
-        }
-        return Ok((&input[i..], str::from_utf8(&input[..i]).unwrap()));
-    }
-    Ok((&input[1..], str::from_utf8(&input[..1]).unwrap()))
-}
-
-#[inline]
-fn non_ascii(chr: u8) -> bool {
-    chr >= 0x80 && chr <= 0xFD
-}
-
-fn expr_bool_lit(i: &[u8]) -> IResult<&[u8], Expr> {
-    map(alt((tag("false"), tag("true"))), |s| {
-        Expr::BoolLit(str::from_utf8(s).unwrap())
-    })(i)
-}
-
-fn num_lit(i: &[u8]) -> IResult<&[u8], &str> {
-    map(digit1, |s| str::from_utf8(s).unwrap())(i)
-}
-
-fn expr_num_lit(i: &[u8]) -> IResult<&[u8], Expr> {
-    map(num_lit, |s| Expr::NumLit(s))(i)
-}
-
-fn expr_array_lit(i: &[u8]) -> IResult<&[u8], Expr> {
-    delimited(
-        ws(tag("[")),
-        map(separated_nonempty_list(ws(tag(",")), expr_any), |arr| {
-            Expr::Array(arr)
-        }),
-        ws(tag("]")),
-    )(i)
-}
-
-fn variant_num_lit(i: &[u8]) -> IResult<&[u8], MatchVariant> {
-    map(num_lit, |s| MatchVariant::NumLit(s))(i)
-}
-
-fn param_num_lit(i: &[u8]) -> IResult<&[u8], MatchParameter> {
-    map(num_lit, |s| MatchParameter::NumLit(s))(i)
-}
-
-fn str_lit(i: &[u8]) -> IResult<&[u8], &str> {
-    map(
-        delimited(
-            char('\"'),
-            opt(escaped(is_not("\\\""), '\\', anychar)),
-            char('\"'),
-        ),
-        |s| s.map(|s| str::from_utf8(s).unwrap()).unwrap_or(""),
-    )(i)
-}
-
-fn expr_str_lit(i: &[u8]) -> IResult<&[u8], Expr> {
-    map(str_lit, |s| Expr::StrLit(s))(i)
-}
-
-fn variant_str_lit(i: &[u8]) -> IResult<&[u8], MatchVariant> {
-    map(str_lit, |s| MatchVariant::StrLit(s))(i)
-}
-
-fn param_str_lit(i: &[u8]) -> IResult<&[u8], MatchParameter> {
-    map(str_lit, |s| MatchParameter::StrLit(s))(i)
-}
-
-fn char_lit(i: &[u8]) -> IResult<&[u8], &str> {
-    map(
-        delimited(
-            char('\''),
-            opt(escaped(is_not("\\\'"), '\\', anychar)),
-            char('\''),
-        ),
-        |s| s.map(|s| str::from_utf8(s).unwrap()).unwrap_or(""),
-    )(i)
-}
-
-fn expr_char_lit(i: &[u8]) -> IResult<&[u8], Expr> {
-    map(char_lit, |s| Expr::CharLit(s))(i)
-}
-
-fn variant_char_lit(i: &[u8]) -> IResult<&[u8], MatchVariant> {
-    map(char_lit, |s| MatchVariant::CharLit(s))(i)
-}
-
-fn param_char_lit(i: &[u8]) -> IResult<&[u8], MatchParameter> {
-    map(char_lit, |s| MatchParameter::CharLit(s))(i)
-}
-
-fn expr_var(i: &[u8]) -> IResult<&[u8], Expr> {
-    map(identifier, |s| Expr::Var(s))(i)
-}
-
-fn expr_path(i: &[u8]) -> IResult<&[u8], Expr> {
-    let tail = separated_nonempty_list(tag("::"), identifier);
-    let (i, (start, _, rest)) = tuple((identifier, tag("::"), tail))(i)?;
-
-    let mut path = vec![start];
-    path.extend(rest);
-    Ok((i, Expr::Path(path)))
-}
-
-fn variant_path(i: &[u8]) -> IResult<&[u8], MatchVariant> {
-    map(separated_nonempty_list(tag("::"), identifier), |path| {
-        MatchVariant::Path(path)
-    })(i)
-}
-
-fn target_single(i: &[u8]) -> IResult<&[u8], Target> {
-    map(identifier, |s| Target::Name(s))(i)
-}
-
-fn target_tuple(i: &[u8]) -> IResult<&[u8], Target> {
-    let parts = separated_list(tag(","), ws(identifier));
-    let trailing = opt(ws(tag(",")));
-    let full = delimited(tag("("), tuple((parts, trailing)), tag(")"));
-
-    let (i, (elems, _)) = full(i)?;
-    Ok((i, Target::Tuple(elems)))
-}
-
-fn variant_name(i: &[u8]) -> IResult<&[u8], MatchVariant> {
-    map(identifier, |s| MatchVariant::Name(s))(i)
-}
-
-fn param_name(i: &[u8]) -> IResult<&[u8], MatchParameter> {
-    map(identifier, |s| MatchParameter::Name(s))(i)
-}
-
-fn arguments(i: &[u8]) -> IResult<&[u8], Vec<Expr>> {
-    delimited(tag("("), separated_list(tag(","), ws(expr_any)), tag(")"))(i)
-}
-
-fn macro_arguments(i: &[u8]) -> IResult<&[u8], &str> {
-    delimited(char('('), nested_parenthesis, char(')'))(i)
-}
-
-fn nested_parenthesis(i: &[u8]) -> ParserError<&str> {
-    let mut nested = 0;
-    let mut last = 0;
-    let mut in_str = false;
-    let mut escaped = false;
-
-    for (i, b) in i.iter().enumerate() {
-        if !(*b == b'(' || *b == b')') || !in_str {
-            match *b {
-                b'(' => nested += 1,
-                b')' => {
-                    if nested == 0 {
-                        last = i;
-                        break;
-                    }
-                    nested -= 1;
-                }
-                b'"' => {
-                    if in_str {
-                        if !escaped {
-                            in_str = false;
-                        }
-                    } else {
-                        in_str = true;
-                    }
-                }
-                b'\\' => {
-                    escaped = !escaped;
-                }
-                _ => (),
-            }
-        }
-
-        if escaped && *b != b'\\' {
-            escaped = false;
-        }
-    }
-
-    if nested == 0 {
-        Ok((&i[last..], str::from_utf8(&i[..last]).unwrap()))
-    } else {
-        Err(nom::Err::Error(error_position!(
-            i,
-            nom::error::ErrorKind::SeparatedNonEmptyList
-        )))
-    }
-}
-
-fn parameters(i: &[u8]) -> IResult<&[u8], Vec<&str>> {
-    delimited(tag("("), separated_list(tag(","), ws(identifier)), tag(")"))(i)
-}
-
-fn with_parameters(i: &[u8]) -> IResult<&[u8], MatchParameters> {
-    let (i, (_, value)) = tuple((
-        tag("with"),
-        alt((match_simple_parameters, match_named_parameters)),
-    ))(i)?;
-    Ok((i, value))
-}
-
-fn match_simple_parameters(i: &[u8]) -> IResult<&[u8], MatchParameters> {
-    delimited(
-        ws(tag("(")),
-        map(separated_list(tag(","), ws(match_parameter)), |mps| {
-            MatchParameters::Simple(mps)
-        }),
-        tag(")"),
-    )(i)
-}
-
-fn match_named_parameters(i: &[u8]) -> IResult<&[u8], MatchParameters> {
-    delimited(
-        ws(tag("{")),
-        map(separated_list(tag(","), ws(match_named_parameter)), |mps| {
-            MatchParameters::Named(mps)
-        }),
-        tag("}"),
-    )(i)
-}
-
-fn expr_group(i: &[u8]) -> IResult<&[u8], Expr> {
-    map(delimited(char('('), expr_any, char(')')), |s| {
-        Expr::Group(Box::new(s))
-    })(i)
-}
-
-fn expr_single(i: &[u8]) -> IResult<&[u8], Expr> {
-    alt((
-        expr_bool_lit,
-        expr_num_lit,
-        expr_str_lit,
-        expr_char_lit,
-        expr_path,
-        expr_rust_macro,
-        expr_array_lit,
-        expr_var,
-        expr_group,
-    ))(i)
-}
-
-fn match_variant(i: &[u8]) -> IResult<&[u8], MatchVariant> {
-    alt((
-        variant_path,
-        variant_name,
-        variant_num_lit,
-        variant_str_lit,
-        variant_char_lit,
-    ))(i)
-}
-
-fn match_parameter(i: &[u8]) -> IResult<&[u8], MatchParameter> {
-    alt((param_name, param_num_lit, param_str_lit, param_char_lit))(i)
-}
-
-fn match_named_parameter(i: &[u8]) -> IResult<&[u8], (&str, Option<MatchParameter>)> {
-    let param = tuple((ws(tag(":")), match_parameter));
-    let (i, (name, param)) = tuple((identifier, opt(param)))(i)?;
-    Ok((i, (name, param.map(|s| s.1))))
-}
-
-fn attr(i: &[u8]) -> IResult<&[u8], (&str, Option<Vec<Expr>>)> {
-    let (i, (_, attr, args)) = tuple((tag("."), alt((num_lit, identifier)), opt(arguments)))(i)?;
-    Ok((i, (attr, args)))
-}
-
-fn expr_attr(i: &[u8]) -> IResult<&[u8], Expr> {
-    let (i, (obj, attrs)) = tuple((expr_single, many0(attr)))(i)?;
-
-    let mut res = obj;
-    for (aname, args) in attrs {
-        res = if let Some(args) = args {
-            Expr::MethodCall(Box::new(res), aname, args)
-        } else {
-            Expr::Attr(Box::new(res), aname)
-        };
-    }
-
-    Ok((i, res))
-}
-
-fn expr_index(i: &[u8]) -> IResult<&[u8], Expr> {
-    let key = opt(tuple((ws(tag("[")), expr_any, ws(tag("]")))));
-    let (i, (obj, key)) = tuple((expr_attr, key))(i)?;
-    let key = key.map(|(_, key, _)| key);
-
-    Ok((
-        i,
-        match key {
-            Some(key) => Expr::Index(Box::new(obj), Box::new(key)),
-            None => obj,
-        },
-    ))
-}
-
-fn filter(i: &[u8]) -> IResult<&[u8], (&str, Option<Vec<Expr>>)> {
-    let (i, (_, fname, args)) = tuple((tag("|"), identifier, opt(arguments)))(i)?;
-    Ok((i, (fname, args)))
-}
-
-fn expr_filtered(i: &[u8]) -> IResult<&[u8], Expr> {
-    let (i, (obj, filters)) = tuple((expr_index, many0(filter)))(i)?;
-
-    let mut res = obj;
-    for (fname, args) in filters {
-        res = Expr::Filter(fname, {
-            let mut args = match args {
-                Some(inner) => inner,
-                None => Vec::new(),
-            };
-            args.insert(0, res);
-            args
-        });
-    }
-
-    Ok((i, res))
-}
-
-fn expr_unary(i: &[u8]) -> IResult<&[u8], Expr> {
-    let (i, (op, expr)) = tuple((opt(alt((tag("!"), tag("-")))), expr_filtered))(i)?;
-    Ok((
-        i,
-        match op {
-            Some(op) => Expr::Unary(str::from_utf8(op).unwrap(), Box::new(expr)),
-            None => expr,
-        },
-    ))
-}
-
-fn expr_rust_macro(i: &[u8]) -> IResult<&[u8], Expr> {
-    let (i, (mname, _, args)) = tuple((identifier, tag("!"), macro_arguments))(i)?;
-    Ok((i, Expr::RustMacro(mname, args)))
-}
-
-macro_rules! expr_prec_layer {
-    ( $name:ident, $inner:ident, $op:expr ) => {
-        fn $name(i: &[u8]) -> IResult<&[u8], Expr> {
-            let (i, (left, op_and_right)) = tuple((
-                $inner,
-                opt(pair(
-                    ws(tag($op)),
-                    expr_any,
-                ))
-            ))(i)?;
-            Ok((i, match op_and_right {
-                Some((op, right)) => Expr::BinOp(
-                    str::from_utf8(op).unwrap(), Box::new(left), Box::new(right)
-                ),
-                None => left,
-            }))
-        }
-    };
-    ( $name:ident, $inner:ident, $( $op:expr ),+ ) => {
-        fn $name(i: &[u8]) -> IResult<&[u8], Expr> {
-            let (i, (left, op_and_right)) = tuple((
-                $inner,
-                opt(pair(
-                    ws(alt(($( tag($op) ),*,))),
-                    expr_any
-                ))
-            ))(i)?;
-            Ok((i, match op_and_right {
-                Some((op, right)) => Expr::BinOp(
-                    str::from_utf8(op).unwrap(), Box::new(left), Box::new(right)
-                ),
-                None => left,
-            }))
-        }
-    }
-}
-
-expr_prec_layer!(expr_muldivmod, expr_unary, "*", "/", "%");
-expr_prec_layer!(expr_addsub, expr_muldivmod, "+", "-");
-expr_prec_layer!(expr_shifts, expr_addsub, ">>", "<<");
-expr_prec_layer!(expr_band, expr_shifts, "&");
-expr_prec_layer!(expr_bxor, expr_band, "^");
-expr_prec_layer!(expr_bor, expr_bxor, "|");
-expr_prec_layer!(expr_compare, expr_bor, "==", "!=", ">=", ">", "<=", "<");
-expr_prec_layer!(expr_and, expr_compare, "&&");
-expr_prec_layer!(expr_or, expr_and, "||");
-
-fn range_right(i: &[u8]) -> IResult<&[u8], Expr> {
-    let (i, (_, incl, right)) = tuple((ws(tag("..")), opt(ws(tag("="))), opt(expr_or)))(i)?;
-    Ok((
-        i,
-        Expr::Range(
-            if incl.is_some() { "..=" } else { ".." },
-            None,
-            right.map(Box::new),
-        ),
-    ))
-}
-
-fn expr_any(i: &[u8]) -> IResult<&[u8], Expr> {
-    let compound = map(tuple((expr_or, range_right)), |(left, rest)| match rest {
-        Expr::Range(op, _, right) => Expr::Range(op, Some(Box::new(left)), right),
-        _ => unreachable!(),
-    });
-    let p = alt((range_right, compound, expr_or));
-    Ok(p(i)?)
-}
-
-fn expr_node<'a>(i: &'a [u8], s: &'a Syntax<'a>) -> IResult<&'a [u8], Node<'a>> {
-    let p = tuple((
-        |i| tag_expr_start(i, s),
-        opt(tag("-")),
-        ws(expr_any),
-        opt(tag("-")),
-        |i| tag_expr_end(i, s),
-    ));
-    let (i, (_, pws, expr, nws, _)) = p(i)?;
-    Ok((i, Node::Expr(WS(pws.is_some(), nws.is_some()), expr)))
-}
-
-fn block_call(i: &[u8]) -> IResult<&[u8], Node> {
-    let p = tuple((
-        opt(tag("-")),
-        ws(tag("call")),
-        opt(tuple((ws(identifier), ws(tag("::"))))),
-        ws(identifier),
-        ws(arguments),
-        opt(tag("-")),
-    ));
-    let (i, (pws, _, scope, name, args, nws)) = p(i)?;
-    let scope = scope.map(|(scope, _)| scope);
-    Ok((
-        i,
-        Node::Call(WS(pws.is_some(), nws.is_some()), scope, name, args),
-    ))
-}
-
-fn cond_if(i: &[u8]) -> IResult<&[u8], Expr> {
-    let (i, (_, cond)) = tuple((ws(tag("if")), ws(expr_any)))(i)?;
-    Ok((i, cond))
-}
-
-fn cond_block<'a>(i: &'a [u8], s: &'a Syntax<'a>) -> IResult<&'a [u8], Cond<'a>> {
-    let p = tuple((
-        |i| tag_block_start(i, s),
-        opt(tag("-")),
-        ws(tag("else")),
-        opt(cond_if),
-        opt(tag("-")),
-        |i| tag_block_end(i, s),
-        |i| parse_template(i, s),
-    ));
-    let (i, (_, pws, _, cond, nws, _, block)) = p(i)?;
-    Ok((i, (WS(pws.is_some(), nws.is_some()), cond, block)))
-}
-
-fn block_if<'a>(i: &'a [u8], s: &'a Syntax<'a>) -> IResult<&'a [u8], Node<'a>> {
-    let p = tuple((
-        opt(tag("-")),
-        cond_if,
-        opt(tag("-")),
-        |i| tag_block_end(i, s),
-        |i| parse_template(i, s),
-        many0(|i| cond_block(i, s)),
-        |i| tag_block_start(i, s),
-        opt(tag("-")),
-        ws(tag("endif")),
-        opt(tag("-")),
-    ));
-    let (i, (pws1, cond, nws1, _, block, elifs, _, pws2, _, nws2)) = p(i)?;
-
-    let mut res = Vec::new();
-    res.push((WS(pws1.is_some(), nws1.is_some()), Some(cond), block));
-    res.extend(elifs);
-    Ok((i, Node::Cond(res, WS(pws2.is_some(), nws2.is_some()))))
-}
-
-fn match_else_block<'a>(i: &'a [u8], s: &'a Syntax<'a>) -> IResult<&'a [u8], When<'a>> {
-    let p = tuple((
-        |i| tag_block_start(i, s),
-        opt(tag("-")),
-        ws(tag("else")),
-        opt(tag("-")),
-        |i| tag_block_end(i, s),
-        |i| parse_template(i, s),
-    ));
-    let (i, (_, pws, _, nws, _, block)) = p(i)?;
-    Ok((
-        i,
-        (
-            WS(pws.is_some(), nws.is_some()),
-            None,
-            MatchParameters::Simple(vec![]),
-            block,
-        ),
-    ))
-}
-
-fn when_block<'a>(i: &'a [u8], s: &'a Syntax<'a>) -> IResult<&'a [u8], When<'a>> {
-    let p = tuple((
-        |i| tag_block_start(i, s),
-        opt(tag("-")),
-        ws(tag("when")),
-        ws(match_variant),
-        opt(ws(with_parameters)),
-        opt(tag("-")),
-        |i| tag_block_end(i, s),
-        |i| parse_template(i, s),
-    ));
-    let (i, (_, pws, _, variant, params, nws, _, block)) = p(i)?;
-    Ok((
-        i,
-        (
-            WS(pws.is_some(), nws.is_some()),
-            Some(variant),
-            params.unwrap_or_default(),
-            block,
-        ),
-    ))
-}
-
-fn block_match<'a>(i: &'a [u8], s: &'a Syntax<'a>) -> IResult<&'a [u8], Node<'a>> {
-    let p = tuple((
-        opt(tag("-")),
-        ws(tag("match")),
-        ws(expr_any),
-        opt(tag("-")),
-        |i| tag_block_end(i, s),
-        opt(|i| take_content(i, s)),
-        many1(|i| when_block(i, s)),
-        opt(|i| match_else_block(i, s)),
-        ws(|i| tag_block_start(i, s)),
-        opt(tag("-")),
-        ws(tag("endmatch")),
-        opt(tag("-")),
-    ));
-    let (i, (pws1, _, expr, nws1, _, inter, arms, else_arm, _, pws2, _, nws2)) = p(i)?;
-
-    let mut arms = arms;
-    if let Some(arm) = else_arm {
-        arms.push(arm);
-    }
-
-    let inter = match inter {
-        Some(Node::Lit(lws, val, rws)) => {
-            assert!(
-                val.is_empty(),
-                "only whitespace allowed between match and first when, found {}",
-                val
-            );
-            assert!(
-                rws.is_empty(),
-                "only whitespace allowed between match and first when, found {}",
-                rws
-            );
-            Some(lws)
-        }
-        None => None,
-        _ => panic!("only literals allowed between match and first when"),
-    };
-
-    Ok((
-        i,
-        Node::Match(
-            WS(pws1.is_some(), nws1.is_some()),
-            expr,
-            inter,
-            arms,
-            WS(pws2.is_some(), nws2.is_some()),
-        ),
-    ))
-}
-
-fn block_let(i: &[u8]) -> IResult<&[u8], Node> {
-    let p = tuple((
-        opt(tag("-")),
-        ws(tag("let")),
-        ws(alt((target_single, target_tuple))),
-        opt(tuple((ws(tag("=")), ws(expr_any)))),
-        opt(tag("-")),
-    ));
-    let (i, (pws, _, var, val, nws)) = p(i)?;
-
-    Ok((
-        i,
-        if let Some((_, val)) = val {
-            Node::Let(WS(pws.is_some(), nws.is_some()), var, val)
-        } else {
-            Node::LetDecl(WS(pws.is_some(), nws.is_some()), var)
-        },
-    ))
-}
-
-fn block_for<'a>(i: &'a [u8], s: &'a Syntax<'a>) -> IResult<&'a [u8], Node<'a>> {
-    let p = tuple((
-        opt(tag("-")),
-        ws(tag("for")),
-        ws(alt((target_single, target_tuple))),
-        ws(tag("in")),
-        ws(expr_any),
-        opt(tag("-")),
-        |i| tag_block_end(i, s),
-        |i| parse_template(i, s),
-        |i| tag_block_start(i, s),
-        opt(tag("-")),
-        ws(tag("endfor")),
-        opt(tag("-")),
-    ));
-    let (i, (pws1, _, var, _, iter, nws1, _, block, _, pws2, _, nws2)) = p(i)?;
-    Ok((
-        i,
-        Node::Loop(
-            WS(pws1.is_some(), nws1.is_some()),
-            var,
-            iter,
-            block,
-            WS(pws2.is_some(), nws2.is_some()),
-        ),
-    ))
-}
-
-fn block_extends(i: &[u8]) -> IResult<&[u8], Node> {
-    let (i, (_, name)) = tuple((ws(tag("extends")), ws(expr_str_lit)))(i)?;
-    Ok((i, Node::Extends(name)))
-}
-
-fn block_block<'a>(i: &'a [u8], s: &'a Syntax<'a>) -> IResult<&'a [u8], Node<'a>> {
-    let start = tuple((
-        opt(tag("-")),
-        ws(tag("block")),
-        ws(identifier),
-        opt(tag("-")),
-        |i| tag_block_end(i, s),
-        |i| parse_template(i, s),
-    ));
-    let (i, (pws1, _, name, nws1, _, contents)) = start(i)?;
-
-    let end = tuple((
-        |i| tag_block_start(i, s),
-        opt(tag("-")),
-        ws(tag("endblock")),
-        opt(ws(tag(name))),
-        opt(tag("-")),
-    ));
-    let (i, (_, pws2, _, _, nws2)) = end(i)?;
-
-    Ok((
-        i,
-        Node::BlockDef(
-            WS(pws1.is_some(), nws1.is_some()),
-            name,
-            contents,
-            WS(pws2.is_some(), nws2.is_some()),
-        ),
-    ))
-}
-
-fn block_include(i: &[u8]) -> IResult<&[u8], Node> {
-    let p = tuple((
-        opt(tag("-")),
-        ws(tag("include")),
-        ws(expr_str_lit),
-        opt(tag("-")),
-    ));
-    let (i, (pws, _, name, nws)) = p(i)?;
-    Ok((
-        i,
-        Node::Include(
-            WS(pws.is_some(), nws.is_some()),
-            match name {
-                Expr::StrLit(s) => s,
-                _ => panic!("include path must be a string literal"),
-            },
-        ),
-    ))
-}
-
-fn block_import(i: &[u8]) -> IResult<&[u8], Node> {
-    let p = tuple((
-        opt(tag("-")),
-        ws(tag("import")),
-        ws(expr_str_lit),
-        ws(tag("as")),
-        ws(identifier),
-        opt(tag("-")),
-    ));
-    let (i, (pws, _, name, _, scope, nws)) = p(i)?;
-    Ok((
-        i,
-        Node::Import(
-            WS(pws.is_some(), nws.is_some()),
-            match name {
-                Expr::StrLit(s) => s,
-                _ => panic!("import path must be a string literal"),
-            },
-            scope,
-        ),
-    ))
-}
-
-fn block_macro<'a>(i: &'a [u8], s: &'a Syntax<'a>) -> IResult<&'a [u8], Node<'a>> {
-    let p = tuple((
-        opt(tag("-")),
-        ws(tag("macro")),
-        ws(identifier),
-        ws(parameters),
-        opt(tag("-")),
-        |i| tag_block_end(i, s),
-        |i| parse_template(i, s),
-        |i| tag_block_start(i, s),
-        opt(tag("-")),
-        ws(tag("endmacro")),
-        opt(tag("-")),
-    ));
-
-    let (i, (pws1, _, name, params, nws1, _, contents, _, pws2, _, nws2)) = p(i)?;
-    if name == "super" {
-        panic!("invalid macro name 'super'");
-    }
-
-    Ok((
-        i,
-        Node::Macro(
-            name,
-            Macro {
-                ws1: WS(pws1.is_some(), nws1.is_some()),
-                args: params,
-                nodes: contents,
-                ws2: WS(pws2.is_some(), nws2.is_some()),
-            },
-        ),
-    ))
-}
-
-fn block_raw<'a>(i: &'a [u8], s: &'a Syntax<'a>) -> IResult<&'a [u8], Node<'a>> {
-    let p = tuple((
-        opt(tag("-")),
-        ws(tag("raw")),
-        opt(tag("-")),
-        |i| tag_block_end(i, s),
-        take_until("{% endraw %}"),
-        |i| tag_block_start(i, s),
-        opt(tag("-")),
-        ws(tag("endraw")),
-        opt(tag("-")),
-    ));
-
-    let (i, (pws1, _, nws1, _, contents, _, pws2, _, nws2)) = p(i)?;
-    let str_contents = str::from_utf8(contents).unwrap();
-    Ok((
-        i,
-        Node::Raw(
-            WS(pws1.is_some(), nws1.is_some()),
-            str_contents,
-            WS(pws2.is_some(), nws2.is_some()),
-        ),
-    ))
-}
-
-fn block_node<'a>(i: &'a [u8], s: &'a Syntax<'a>) -> IResult<&'a [u8], Node<'a>> {
-    let p = tuple((
-        |i| tag_block_start(i, s),
-        alt((
-            block_call,
-            block_let,
-            |i| block_if(i, s),
-            |i| block_for(i, s),
-            |i| block_match(i, s),
-            block_extends,
-            block_include,
-            block_import,
-            |i| block_block(i, s),
-            |i| block_macro(i, s),
-            |i| block_raw(i, s),
-        )),
-        |i| tag_block_end(i, s),
-    ));
-    let (i, (_, contents, _)) = p(i)?;
-    Ok((i, contents))
-}
-
-fn block_comment<'a>(i: &'a [u8], s: &'a Syntax<'a>) -> IResult<&'a [u8], Node<'a>> {
-    let p = tuple((
-        |i| tag_comment_start(i, s),
-        opt(tag("-")),
-        take_until(s.comment_end),
-        |i| tag_comment_end(i, s),
-    ));
-    let (i, (_, pws, inner, _)) = p(i)?;
-    Ok((
-        i,
-        Node::Comment(WS(
-            pws.is_some(),
-            inner.len() > 1 && inner[inner.len() - 1] == b'-',
-        )),
-    ))
-}
-
-fn parse_template<'a>(i: &'a [u8], s: &'a Syntax<'a>) -> IResult<&'a [u8], Vec<Node<'a>>> {
-    many0(alt((
-        complete(|i| take_content(i, s)),
-        complete(|i| block_comment(i, s)),
-        complete(|i| expr_node(i, s)),
-        complete(|i| block_node(i, s)),
-    )))(i)
-}
-
-fn tag_block_start<'a>(i: &'a [u8], s: &'a Syntax<'a>) -> IResult<&'a [u8], &'a [u8]> {
-    tag(s.block_start)(i)
-}
-fn tag_block_end<'a>(i: &'a [u8], s: &'a Syntax<'a>) -> IResult<&'a [u8], &'a [u8]> {
-    tag(s.block_end)(i)
-}
-fn tag_comment_start<'a>(i: &'a [u8], s: &'a Syntax<'a>) -> IResult<&'a [u8], &'a [u8]> {
-    tag(s.comment_start)(i)
-}
-fn tag_comment_end<'a>(i: &'a [u8], s: &'a Syntax<'a>) -> IResult<&'a [u8], &'a [u8]> {
-    tag(s.comment_end)(i)
-}
-fn tag_expr_start<'a>(i: &'a [u8], s: &'a Syntax<'a>) -> IResult<&'a [u8], &'a [u8]> {
-    tag(s.expr_start)(i)
-}
-fn tag_expr_end<'a>(i: &'a [u8], s: &'a Syntax<'a>) -> IResult<&'a [u8], &'a [u8]> {
-    tag(s.expr_end)(i)
-}
-
-pub fn parse<'a>(src: &'a str, syntax: &'a Syntax<'a>) -> Vec<Node<'a>> {
-    match parse_template(src.as_bytes(), syntax) {
-        Ok((left, res)) => {
-            if !left.is_empty() {
-                let s = str::from_utf8(left).unwrap();
-                panic!("unable to parse template:\n\n{:?}", s);
-            } else {
-                res
-            }
-        }
-        Err(nom::Err::Error(err)) => panic!("problems parsing template source: {:?}", err),
-        Err(nom::Err::Failure(err)) => panic!("problems parsing template source: {:?}", err),
-        Err(nom::Err::Incomplete(_)) => panic!("parsing incomplete"),
-    }
-}
-
-#[cfg(test)]
-mod tests {
-    use askama_shared::Syntax;
-
-    fn check_ws_split(s: &str, res: &(&str, &str, &str)) {
-        let node = super::split_ws_parts(s.as_bytes());
-        match node {
-            super::Node::Lit(lws, s, rws) => {
-                assert_eq!(lws, res.0);
-                assert_eq!(s, res.1);
-                assert_eq!(rws, res.2);
-            }
-            _ => {
-                panic!("fail");
-            }
-        }
-    }
-
-    #[test]
-    fn test_ws_splitter() {
-        check_ws_split("", &("", "", ""));
-        check_ws_split("a", &("", "a", ""));
-        check_ws_split("\ta", &("\t", "a", ""));
-        check_ws_split("b\n", &("", "b", "\n"));
-        check_ws_split(" \t\r\n", &(" \t\r\n", "", ""));
-    }
-
-    #[test]
-    #[should_panic]
-    fn test_invalid_block() {
-        super::parse("{% extend \"blah\" %}", &Syntax::default());
-    }
-
-    #[test]
-    fn test_parse_filter() {
-        super::parse("{{ strvar|e }}", &Syntax::default());
-    }
-
-    #[test]
-    fn change_delimiters_parse_filter() {
-        let syntax = Syntax {
-            expr_start: "{~",
-            expr_end: "~}",
-            ..Syntax::default()
-        };
-
-        super::parse("{~ strvar|e ~}", &syntax);
-    }
-}
-
-type ParserError<'a, T> = Result<(&'a [u8], T), nom::Err<(&'a [u8], nom::error::ErrorKind)>>;