Implement fixed width area.

src/parser/fixed_width_area.rs

@@ -1,5 +1,23 @@
+use nom::branch::alt;
+use nom::bytes::complete::is_not;
+use nom::bytes::complete::tag;
+use nom::character::complete::line_ending;
+use nom::character::complete::space0;
+use nom::character::complete::space1;
+use nom::combinator::eof;
+use nom::combinator::not;
+use nom::combinator::opt;
+use nom::multi::many0;
+use nom::sequence::preceded;
+use nom::sequence::tuple;
+
 use super::Context;
 use crate::error::Res;
+use crate::parser::parser_with_context::parser_with_context;
+use crate::parser::util::exit_matcher_parser;
+use crate::parser::util::get_consumed;
+use crate::parser::util::maybe_consume_trailing_whitespace_if_not_exiting;
+use crate::parser::util::start_of_line;
 use crate::parser::FixedWidthArea;
 
 #[tracing::instrument(ret, level = "debug")]
@@ -7,5 +25,31 @@ pub fn fixed_width_area<'r, 's>(
     context: Context<'r, 's>,
     input: &'s str,
 ) -> Res<&'s str, FixedWidthArea<'s>> {
-    todo!()
+    let fixed_width_area_line_matcher = parser_with_context!(fixed_width_area_line)(context);
+    let exit_matcher = parser_with_context!(exit_matcher_parser)(context);
+    let (remaining, _first_line) = fixed_width_area_line_matcher(input)?;
+    let (remaining, _remaining_lines) =
+        many0(preceded(not(exit_matcher), fixed_width_area_line_matcher))(remaining)?;
+
+    let (remaining, _trailing_ws) =
+        maybe_consume_trailing_whitespace_if_not_exiting(context, remaining)?;
+
+    let source = get_consumed(input, remaining);
+    Ok((remaining, FixedWidthArea { source }))
+}
+
+#[tracing::instrument(ret, level = "debug")]
+fn fixed_width_area_line<'r, 's>(
+    context: Context<'r, 's>,
+    input: &'s str,
+) -> Res<&'s str, &'s str> {
+    start_of_line(context, input)?;
+    let (remaining, _indent) = space0(input)?;
+    let (remaining, (_hash, _leading_whitespace_and_content, _line_ending)) = tuple((
+        tag(":"),
+        opt(tuple((space1, is_not("\r\n")))),
+        alt((line_ending, eof)),
+    ))(remaining)?;
+    let source = get_consumed(input, remaining);
+    Ok((remaining, source))
 }