nushell/src/parser/hir/syntax_shape/expression/string.rs
Yehuda Katz 6a7c00eaef Finish the job of moving shapes into the stream
This commit should finish the `coloring_in_tokens` feature, which moves
the shape accumulator into the token stream. This allows rollbacks of
the token stream to also roll back any shapes that were added.

This commit also adds a much nicer syntax highlighter trace, which shows
all of the paths the highlighter took to arrive at a particular coloring
output. This change is fairly substantial, but really improves the
understandability of the flow. I intend to update the normal parser with
a similar tracing view.

In general, this change also fleshes out the concept of "atomic" token
stream operations.

A good next step would be to try to make the parser more
error-correcting, using the coloring infrastructure. A follow-up step
would involve merging the parser and highlighter shapes themselves.
2019-10-22 16:19:22 -07:00

130 lines
3.9 KiB
Rust

use crate::parser::hir::syntax_shape::{
expand_atom, expand_variable, parse_single_node, AtomicToken, ExpandContext, ExpandExpression,
ExpansionRule, FallibleColorSyntax, FlatShape, TestSyntax,
};
use crate::parser::hir::tokens_iterator::Peeked;
use crate::parser::{hir, hir::TokensIterator, RawToken, TokenNode};
use crate::prelude::*;
#[derive(Debug, Copy, Clone)]
pub struct StringShape;
#[cfg(not(coloring_in_tokens))]
impl FallibleColorSyntax for StringShape {
type Info = ();
type Input = FlatShape;
fn color_syntax<'a, 'b>(
&self,
input: &FlatShape,
token_nodes: &'b mut TokensIterator<'a>,
context: &ExpandContext,
shapes: &mut Vec<Spanned<FlatShape>>,
) -> Result<(), ShellError> {
let atom = expand_atom(token_nodes, "string", context, ExpansionRule::permissive());
let atom = match atom {
Err(_) => return Ok(()),
Ok(atom) => atom,
};
match atom {
Spanned {
item: AtomicToken::String { .. },
span,
} => shapes.push((*input).spanned(span)),
other => other.color_tokens(shapes),
}
Ok(())
}
}
#[cfg(coloring_in_tokens)]
impl FallibleColorSyntax for StringShape {
type Info = ();
type Input = FlatShape;
fn name(&self) -> &'static str {
"StringShape"
}
fn color_syntax<'a, 'b>(
&self,
input: &FlatShape,
token_nodes: &'b mut TokensIterator<'a>,
context: &ExpandContext,
) -> Result<(), ShellError> {
let atom = expand_atom(token_nodes, "string", context, ExpansionRule::permissive());
let atom = match atom {
Err(_) => return Ok(()),
Ok(atom) => atom,
};
match atom {
Spanned {
item: AtomicToken::String { .. },
span,
} => token_nodes.color_shape((*input).spanned(span)),
atom => token_nodes.mutate_shapes(|shapes| atom.color_tokens(shapes)),
}
Ok(())
}
}
impl ExpandExpression for StringShape {
fn expand_expr<'a, 'b>(
&self,
token_nodes: &mut TokensIterator<'_>,
context: &ExpandContext,
) -> Result<hir::Expression, ShellError> {
parse_single_node(token_nodes, "String", |token, token_span, _| {
Ok(match token {
RawToken::GlobPattern => {
return Err(ShellError::type_error(
"String",
"glob pattern".tagged(token_span),
))
}
RawToken::Operator(..) => {
return Err(ShellError::type_error(
"String",
"operator".tagged(token_span),
))
}
RawToken::Variable(span) => expand_variable(span, token_span, &context.source),
RawToken::ExternalCommand(span) => {
hir::Expression::external_command(span, token_span)
}
RawToken::ExternalWord => {
return Err(ShellError::invalid_external_word(token_span))
}
RawToken::Number(_) => hir::Expression::bare(token_span),
RawToken::Bare => hir::Expression::bare(token_span),
RawToken::String(span) => hir::Expression::string(span, token_span),
})
})
}
}
impl TestSyntax for StringShape {
fn test<'a, 'b>(
&self,
token_nodes: &'b mut TokensIterator<'a>,
_context: &ExpandContext,
) -> Option<Peeked<'a, 'b>> {
let peeked = token_nodes.peek_any();
match peeked.node {
Some(TokenNode::Token(token)) => match token.item {
RawToken::String(_) => Some(peeked),
_ => None,
},
_ => None,
}
}
}