Extract askama_parser crate

1 files changed, 0 insertions, 381 deletions

diff --git a/askama_derive/src/parser/mod.rs b/askama_derive/src/parser/mod.rs
deleted file mode 100644
index 8da96f5..0000000
--- a/askama_derive/src/parser/mod.rs
+++ /dev/null
@@ -1,381 +0,0 @@
-use std::cell::Cell;
-use std::{fmt, str};
-
-use nom::branch::alt;
-use nom::bytes::complete::{escaped, is_not, tag, take_till};
-use nom::character::complete::char;
-use nom::character::complete::{anychar, digit1};
-use nom::combinator::{eof, map, not, opt, recognize, value};
-use nom::error::ErrorKind;
-use nom::multi::separated_list1;
-use nom::sequence::{delimited, pair, tuple};
-use nom::{error_position, AsChar, IResult, InputTakeAtPosition};
-
-pub(crate) use self::expr::Expr;
-pub(crate) use self::node::{Cond, CondTest, Loop, Macro, Node, Target, When, Whitespace, Ws};
-
-mod expr;
-mod node;
-#[cfg(test)]
-mod tests;
-
-struct State<'a> {
-    syntax: &'a Syntax<'a>,
-    loop_depth: Cell<usize>,
-}
-
-impl<'a> State<'a> {
-    fn new(syntax: &'a Syntax<'a>) -> State<'a> {
-        State {
-            syntax,
-            loop_depth: Cell::new(0),
-        }
-    }
-
-    fn enter_loop(&self) {
-        self.loop_depth.set(self.loop_depth.get() + 1);
-    }
-
-    fn leave_loop(&self) {
-        self.loop_depth.set(self.loop_depth.get() - 1);
-    }
-
-    fn is_in_loop(&self) -> bool {
-        self.loop_depth.get() > 0
-    }
-}
-
-impl From<char> for Whitespace {
-    fn from(c: char) -> Self {
-        match c {
-            '+' => Self::Preserve,
-            '-' => Self::Suppress,
-            '~' => Self::Minimize,
-            _ => panic!("unsupported `Whitespace` conversion"),
-        }
-    }
-}
-
-mod _parsed {
-    use std::mem;
-
-    use super::{parse, Node, ParseError, Syntax};
-
-    pub(crate) struct Parsed {
-        #[allow(dead_code)]
-        source: String,
-        nodes: Vec<Node<'static>>,
-    }
-
-    impl Parsed {
-        pub(crate) fn new(source: String, syntax: &Syntax<'_>) -> Result<Self, ParseError> {
-            // Self-referential borrowing: `self` will keep the source alive as `String`,
-            // internally we will transmute it to `&'static str` to satisfy the compiler.
-            // However, we only expose the nodes with a lifetime limited to `self`.
-            let src = unsafe { mem::transmute::<&str, &'static str>(source.as_str()) };
-            let nodes = match parse(src, syntax) {
-                Ok(nodes) => nodes,
-                Err(e) => return Err(e),
-            };
-
-            Ok(Self { source, nodes })
-        }
-
-        // The return value's lifetime must be limited to `self` to uphold the unsafe invariant.
-        pub(crate) fn nodes(&self) -> &[Node<'_>] {
-            &self.nodes
-        }
-    }
-}
-
-pub(crate) use _parsed::Parsed;
-
-pub(crate) fn parse<'a>(src: &'a str, syntax: &Syntax<'_>) -> Result<Vec<Node<'a>>, ParseError> {
-    match Node::parse(src, &State::new(syntax)) {
-        Ok((left, res)) => {
-            if !left.is_empty() {
-                Err(ParseError(format!("unable to parse template:\n\n{left:?}")))
-            } else {
-                Ok(res)
-            }
-        }
-
-        Err(nom::Err::Error(err)) | Err(nom::Err::Failure(err)) => {
-            let nom::error::Error { input, .. } = err;
-            let offset = src.len() - input.len();
-            let (source_before, source_after) = src.split_at(offset);
-
-            let source_after = match source_after.char_indices().enumerate().take(41).last() {
-                Some((40, (i, _))) => format!("{:?}...", &source_after[..i]),
-                _ => format!("{source_after:?}"),
-            };
-
-            let (row, last_line) = source_before.lines().enumerate().last().unwrap();
-            let column = last_line.chars().count();
-
-            let msg = format!(
-                "problems parsing template source at row {}, column {} near:\n{}",
-                row + 1,
-                column,
-                source_after,
-            );
-
-            Err(ParseError(msg))
-        }
-
-        Err(nom::Err::Incomplete(_)) => Err(ParseError("parsing incomplete".into())),
-    }
-}
-
-#[derive(Debug, Clone, PartialEq, Eq)]
-pub(crate) struct ParseError(String);
-
-impl std::error::Error for ParseError {}
-
-impl fmt::Display for ParseError {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        self.0.fmt(f)
-    }
-}
-
-fn is_ws(c: char) -> bool {
-    matches!(c, ' ' | '\t' | '\r' | '\n')
-}
-
-fn not_ws(c: char) -> bool {
-    !is_ws(c)
-}
-
-fn ws<'a, O>(
-    inner: impl FnMut(&'a str) -> IResult<&'a str, O>,
-) -> impl FnMut(&'a str) -> IResult<&'a str, O> {
-    delimited(take_till(not_ws), inner, take_till(not_ws))
-}
-
-fn split_ws_parts(s: &str) -> Node<'_> {
-    let trimmed_start = s.trim_start_matches(is_ws);
-    let len_start = s.len() - trimmed_start.len();
-    let trimmed = trimmed_start.trim_end_matches(is_ws);
-    Node::Lit(&s[..len_start], trimmed, &trimmed_start[trimmed.len()..])
-}
-
-/// Skips input until `end` was found, but does not consume it.
-/// Returns tuple that would be returned when parsing `end`.
-fn skip_till<'a, O>(
-    end: impl FnMut(&'a str) -> IResult<&'a str, O>,
-) -> impl FnMut(&'a str) -> IResult<&'a str, (&'a str, O)> {
-    enum Next<O> {
-        IsEnd(O),
-        NotEnd(char),
-    }
-    let mut next = alt((map(end, Next::IsEnd), map(anychar, Next::NotEnd)));
-    move |start: &'a str| {
-        let mut i = start;
-        loop {
-            let (j, is_end) = next(i)?;
-            match is_end {
-                Next::IsEnd(lookahead) => return Ok((i, (j, lookahead))),
-                Next::NotEnd(_) => i = j,
-            }
-        }
-    }
-}
-
-fn keyword<'a>(k: &'a str) -> impl FnMut(&'a str) -> IResult<&'a str, &'a str> {
-    move |i: &'a str| -> IResult<&'a str, &'a str> {
-        let (j, v) = identifier(i)?;
-        if k == v {
-            Ok((j, v))
-        } else {
-            Err(nom::Err::Error(error_position!(i, ErrorKind::Tag)))
-        }
-    }
-}
-
-fn identifier(input: &str) -> IResult<&str, &str> {
-    recognize(pair(identifier_start, opt(identifier_tail)))(input)
-}
-
-fn identifier_start(s: &str) -> IResult<&str, &str> {
-    s.split_at_position1_complete(
-        |c| !(c.is_alpha() || c == '_' || c >= '\u{0080}'),
-        nom::error::ErrorKind::Alpha,
-    )
-}
-
-fn identifier_tail(s: &str) -> IResult<&str, &str> {
-    s.split_at_position1_complete(
-        |c| !(c.is_alphanum() || c == '_' || c >= '\u{0080}'),
-        nom::error::ErrorKind::Alpha,
-    )
-}
-
-fn bool_lit(i: &str) -> IResult<&str, &str> {
-    alt((keyword("false"), keyword("true")))(i)
-}
-
-fn num_lit(i: &str) -> IResult<&str, &str> {
-    recognize(pair(digit1, opt(pair(char('.'), digit1))))(i)
-}
-
-fn str_lit(i: &str) -> IResult<&str, &str> {
-    let (i, s) = delimited(
-        char('"'),
-        opt(escaped(is_not("\\\""), '\\', anychar)),
-        char('"'),
-    )(i)?;
-    Ok((i, s.unwrap_or_default()))
-}
-
-fn char_lit(i: &str) -> IResult<&str, &str> {
-    let (i, s) = delimited(
-        char('\''),
-        opt(escaped(is_not("\\\'"), '\\', anychar)),
-        char('\''),
-    )(i)?;
-    Ok((i, s.unwrap_or_default()))
-}
-
-fn nested_parenthesis(i: &str) -> IResult<&str, ()> {
-    let mut nested = 0;
-    let mut last = 0;
-    let mut in_str = false;
-    let mut escaped = false;
-
-    for (i, b) in i.chars().enumerate() {
-        if !(b == '(' || b == ')') || !in_str {
-            match b {
-                '(' => nested += 1,
-                ')' => {
-                    if nested == 0 {
-                        last = i;
-                        break;
-                    }
-                    nested -= 1;
-                }
-                '"' => {
-                    if in_str {
-                        if !escaped {
-                            in_str = false;
-                        }
-                    } else {
-                        in_str = true;
-                    }
-                }
-                '\\' => {
-                    escaped = !escaped;
-                }
-                _ => (),
-            }
-        }
-
-        if escaped && b != '\\' {
-            escaped = false;
-        }
-    }
-
-    if nested == 0 {
-        Ok((&i[last..], ()))
-    } else {
-        Err(nom::Err::Error(error_position!(
-            i,
-            ErrorKind::SeparatedNonEmptyList
-        )))
-    }
-}
-
-fn path(i: &str) -> IResult<&str, Vec<&str>> {
-    let root = opt(value("", ws(tag("::"))));
-    let tail = separated_list1(ws(tag("::")), identifier);
-
-    match tuple((root, identifier, ws(tag("::")), tail))(i) {
-        Ok((i, (root, start, _, rest))) => {
-            let mut path = Vec::new();
-            path.extend(root);
-            path.push(start);
-            path.extend(rest);
-            Ok((i, path))
-        }
-        Err(err) => {
-            if let Ok((i, name)) = identifier(i) {
-                // The returned identifier can be assumed to be path if:
-                // - Contains both a lowercase and uppercase character, i.e. a type name like `None`
-                // - Doesn't contain any lowercase characters, i.e. it's a constant
-                // In short, if it contains any uppercase characters it's a path.
-                if name.contains(char::is_uppercase) {
-                    return Ok((i, vec![name]));
-                }
-            }
-
-            // If `identifier()` fails then just return the original error
-            Err(err)
-        }
-    }
-}
-
-fn take_content<'a>(i: &'a str, s: &State<'_>) -> IResult<&'a str, Node<'a>> {
-    let p_start = alt((
-        tag(s.syntax.block_start),
-        tag(s.syntax.comment_start),
-        tag(s.syntax.expr_start),
-    ));
-
-    let (i, _) = not(eof)(i)?;
-    let (i, content) = opt(recognize(skip_till(p_start)))(i)?;
-    let (i, content) = match content {
-        Some("") => {
-            // {block,comment,expr}_start follows immediately.
-            return Err(nom::Err::Error(error_position!(i, ErrorKind::TakeUntil)));
-        }
-        Some(content) => (i, content),
-        None => ("", i), // there is no {block,comment,expr}_start: take everything
-    };
-    Ok((i, split_ws_parts(content)))
-}
-
-fn tag_block_start<'a>(i: &'a str, s: &State<'_>) -> IResult<&'a str, &'a str> {
-    tag(s.syntax.block_start)(i)
-}
-
-fn tag_block_end<'a>(i: &'a str, s: &State<'_>) -> IResult<&'a str, &'a str> {
-    tag(s.syntax.block_end)(i)
-}
-
-fn tag_comment_start<'a>(i: &'a str, s: &State<'_>) -> IResult<&'a str, &'a str> {
-    tag(s.syntax.comment_start)(i)
-}
-
-fn tag_comment_end<'a>(i: &'a str, s: &State<'_>) -> IResult<&'a str, &'a str> {
-    tag(s.syntax.comment_end)(i)
-}
-
-fn tag_expr_start<'a>(i: &'a str, s: &State<'_>) -> IResult<&'a str, &'a str> {
-    tag(s.syntax.expr_start)(i)
-}
-
-fn tag_expr_end<'a>(i: &'a str, s: &State<'_>) -> IResult<&'a str, &'a str> {
-    tag(s.syntax.expr_end)(i)
-}
-
-#[derive(Debug)]
-pub(crate) struct Syntax<'a> {
-    pub(crate) block_start: &'a str,
-    pub(crate) block_end: &'a str,
-    pub(crate) expr_start: &'a str,
-    pub(crate) expr_end: &'a str,
-    pub(crate) comment_start: &'a str,
-    pub(crate) comment_end: &'a str,
-}
-
-impl Default for Syntax<'static> {
-    fn default() -> Self {
-        Self {
-            block_start: "{%",
-            block_end: "%}",
-            expr_start: "{{",
-            expr_end: "}}",
-            comment_start: "{#",
-            comment_end: "#}",
-        }
-    }
-}