Files
nushell/crates/nu-parser/src/hir/baseline_parse/tests.rs
Yehuda Katz 7efb31a4e4 Restructure and streamline token expansion (#1123)
Restructure and streamline token expansion

The purpose of this commit is to streamline the token expansion code, by
removing aspects of the code that are no longer relevant, removing
pointless duplication, and eliminating the need to pass the same
arguments to `expand_syntax`.

The first big-picture change in this commit is that instead of a handful
of `expand_` functions, which take a TokensIterator and ExpandContext, a
smaller number of methods on the `TokensIterator` do the same job.

The second big-picture change in this commit is fully eliminating the
coloring traits, making coloring a responsibility of the base expansion
implementations. This also means that the coloring tracer is merged into
the expansion tracer, so you can follow a single expansion and see how
the expansion process produced colored tokens.

One side effect of this change is that the expander itself is marginally
more error-correcting. The error correction works by switching from
structured expansion to `BackoffColoringMode` when an unexpected token
is found, which guarantees that all spans of the source are colored, but
may not be the most optimal error recovery strategy.

That said, because `BackoffColoringMode` only extends as far as a
closing delimiter (`)`, `]`, `}`) or pipe (`|`), it does result in
fairly granular correction strategy.

The current code still produces an `Err` (plus a complete list of
colored shapes) from the parsing process if any errors are encountered,
but this could easily be addressed now that the underlying expansion is
error-correcting.

This commit also colors any spans that are syntax errors in red, and
causes the parser to include some additional information about what
tokens were expected at any given point where an error was encountered,
so that completions and hinting could be more robust in the future.

Co-authored-by: Jonathan Turner <jonathandturner@users.noreply.github.com>
Co-authored-by: Andrés N. Robalino <andres@androbtech.com>
2020-01-21 17:45:03 -05:00

298 lines
8.8 KiB
Rust

use crate::commands::classified::{internal::InternalCommand, ClassifiedCommand};
use crate::hir::expand_external_tokens::{ExternalTokensShape, ExternalTokensSyntax};
use crate::hir::{
self, named::NamedValue, syntax_shape::*, Expression, NamedArguments, SpannedExpression,
TokensIterator,
};
use crate::parse::files::Files;
use crate::parse::token_tree_builder::{CurriedToken, TokenTreeBuilder as b};
use crate::SpannedToken;
use derive_new::new;
use indexmap::IndexMap;
use nu_errors::{ParseError, ShellError};
use nu_protocol::{outln, PathMember, Signature, SyntaxShape};
use nu_source::{HasSpan, PrettyDebugWithSource, Span, SpannedItem, Tag, Text};
use pretty_assertions::assert_eq;
use std::fmt::Debug;
#[test]
fn test_parse_external() {
parse_tokens(
fallible(ExternalTokensShape),
"5kb",
vec![b::bare("5kb")],
|tokens| {
ExternalTokensSyntax::new(
vec![format!("5kb").spanned(tokens[0].span())].spanned(tokens[0].span()),
)
},
);
parse_tokens(
fallible(ExternalTokensShape),
"cargo +nightly run -- --features all",
vec![
b::bare("cargo"),
b::sp(),
b::external_word("+nightly"),
b::sp(),
b::bare("run"),
b::sp(),
b::external_word("--"),
b::sp(),
b::flag("features"),
b::sp(),
b::bare("all"),
],
|tokens| {
let cargo = format!("cargo").spanned(tokens[0].span());
let nightly = format!("+nightly").spanned(tokens[2].span());
let run = format!("run").spanned(tokens[4].span());
let dashdash = format!("--").spanned(tokens[6].span());
let features = format!("--features").spanned(tokens[8].span());
let all = format!("all").spanned(tokens[10].span());
let span = tokens[0].span().until(tokens[10].span());
ExternalTokensSyntax::new(
vec![cargo, nightly, run, dashdash, features, all].spanned(span),
)
},
);
}
#[test]
fn test_parse_string() {
parse_tokens(
CoerceStringShape,
r#""hello""#,
vec![b::string("hello")],
|tokens| {
Expression::string(inner_string_span(tokens[0].span())).into_expr(tokens[0].span())
},
);
}
#[test]
fn test_parse_path() {
let _ = pretty_env_logger::try_init();
parse_expr(
AnyExpressionShape,
"$it.cpu",
vec![b::it_var(), b::dot(), b::bare("cpu")],
|tokens| {
let (outer_var, inner_var) = tokens[0].expect_var();
let bare = tokens[2].expect_bare();
Expression::path(
Expression::it_variable(inner_var).into_expr(outer_var),
vec![PathMember::string("cpu", bare)],
)
.into_expr(outer_var.until(bare))
},
);
parse_expr(
VariablePathShape,
r#"$cpu.amount."max ghz""#,
vec![
b::var("cpu"),
b::dot(),
b::bare("amount"),
b::dot(),
b::string("max ghz"),
],
|tokens| {
let (outer_var, inner_var) = tokens[0].expect_var();
let amount = tokens[2].expect_bare();
let (outer_max_ghz, _) = tokens[4].expect_string();
Expression::path(
Expression::variable(inner_var).into_expr(outer_var),
vec![
PathMember::string("amount", amount),
PathMember::string("max ghz", outer_max_ghz),
],
)
.into_expr(outer_var.until(outer_max_ghz))
},
);
}
#[test]
fn test_parse_command() {
parse_tokens(
fallible(ClassifiedCommandShape),
"ls *.txt",
vec![b::bare("ls"), b::sp(), b::pattern("*.txt")],
|tokens| {
let bare = tokens[0].expect_bare();
let pat = tokens[2].expect_pattern();
let mut map = IndexMap::new();
map.insert("full".to_string(), NamedValue::AbsentSwitch);
map.insert("help".to_string(), NamedValue::AbsentSwitch);
ClassifiedCommand::Internal(InternalCommand::new(
"ls".to_string(),
Tag {
span: bare,
anchor: None,
},
hir::Call {
head: Box::new(Expression::Command(bare).into_expr(bare)),
positional: Some(vec![Expression::pattern("*.txt").into_expr(pat)]),
named: Some(NamedArguments { named: map }),
span: bare.until(pat),
},
))
},
);
}
#[derive(Debug, Clone, new)]
struct TestRegistry {
#[new(default)]
signatures: indexmap::IndexMap<String, Signature>,
}
impl TestRegistry {
fn insert(&mut self, key: &str, value: Signature) {
self.signatures.insert(key.to_string(), value);
}
}
impl SignatureRegistry for TestRegistry {
fn has(&self, name: &str) -> bool {
self.signatures.contains_key(name)
}
fn get(&self, name: &str) -> Option<Signature> {
self.signatures.get(name).cloned()
}
fn clone_box(&self) -> Box<dyn SignatureRegistry> {
Box::new(self.clone())
}
}
fn with_empty_context(source: &Text, callback: impl FnOnce(ExpandContext)) {
let mut registry = TestRegistry::new();
registry.insert(
"ls",
Signature::build("ls")
.optional(
"path",
SyntaxShape::Pattern,
"a path to get the directory contents from",
)
.switch("full", "list all available columns for each entry"),
);
callback(ExpandContext::new(Box::new(registry), source, None))
}
trait Expand {}
fn parse_tokens<T: Eq + HasSpan + PrettyDebugWithSource + Clone + Debug + 'static>(
shape: impl ExpandSyntax<Output = Result<T, ParseError>>,
syntax: &str,
tokens: Vec<CurriedToken>,
expected: impl FnOnce(&[SpannedToken]) -> T,
) {
// let parsed_tokens = parse(syntax);
let tokens = b::token_list(tokens);
let (tokens, source) = b::build(tokens);
let text = Text::from(&source);
assert_eq!(syntax, source);
with_empty_context(&text, |context| {
let tokens = tokens.expect_list();
let mut iterator = TokensIterator::new(&tokens.item, context, tokens.span);
let expr = iterator.expand_syntax(shape);
let expr = match expr {
Ok(expr) => expr,
Err(err) => {
outln!("");
ptree::print_tree(&iterator.expand_tracer().print(text.clone())).unwrap();
outln!("");
print_err(err.into(), &iterator.context().source().clone());
panic!("Parse failed");
}
};
let expected = expected(&tokens.item);
if expr != expected {
outln!("");
ptree::print_tree(&iterator.expand_tracer().print(text.clone())).unwrap();
outln!("");
assert_eq!(expr, expected);
}
})
}
fn parse_expr(
shape: impl ExpandSyntax<Output = Result<SpannedExpression, ParseError>>,
syntax: &str,
tokens: Vec<CurriedToken>,
expected: impl FnOnce(&[SpannedToken]) -> SpannedExpression,
) {
// let parsed_tokens = parse(syntax);
let tokens = b::token_list(tokens);
let (tokens, source) = b::build(tokens);
let text = Text::from(&source);
assert_eq!(syntax, source);
with_empty_context(&text, |context| {
let tokens = tokens.expect_list();
let mut iterator = TokensIterator::new(&tokens.item, context, tokens.span);
let expr = iterator.expand_syntax(shape);
let expr = match expr {
Ok(expr) => expr,
Err(err) => {
outln!("");
ptree::print_tree(&iterator.expand_tracer().print(text.clone())).unwrap();
outln!("");
print_err(err.into(), &iterator.source());
panic!("Parse failed");
}
};
let expected = expected(&tokens.item);
if expr != expected {
outln!("");
ptree::print_tree(&iterator.expand_tracer().print(text.clone())).unwrap();
outln!("");
assert_eq!(expr, expected);
}
})
}
fn inner_string_span(span: Span) -> Span {
Span::new(span.start() + 1, span.end() - 1)
}
pub fn print_err(err: ShellError, source: &Text) {
let diag = err.into_diagnostic();
let writer = termcolor::StandardStream::stderr(termcolor::ColorChoice::Auto);
let mut source = source.to_string();
source.push_str(" ");
let files = Files::new(source);
let _ = language_reporting::emit(
&mut writer.lock(),
&files,
&diag,
&language_reporting::DefaultConfig,
);
}