rustfmt_nightly/parse/
parser.rs
1use std::panic::{AssertUnwindSafe, catch_unwind};
2use std::path::{Path, PathBuf};
3
4use rustc_ast::{ast, attr, ptr};
5use rustc_errors::Diag;
6use rustc_parse::parser::Parser as RawParser;
7use rustc_parse::{exp, new_parser_from_file, new_parser_from_source_str, unwrap_or_emit_fatal};
8use rustc_span::{Span, sym};
9use thin_vec::ThinVec;
10
11use crate::Input;
12use crate::parse::session::ParseSess;
13
14pub(crate) type DirectoryOwnership = rustc_expand::module::DirOwnership;
15pub(crate) type ModulePathSuccess = rustc_expand::module::ModulePathSuccess;
16pub(crate) type ModError<'a> = rustc_expand::module::ModError<'a>;
17
18#[derive(Clone)]
19pub(crate) struct Directory {
20 pub(crate) path: PathBuf,
21 pub(crate) ownership: DirectoryOwnership,
22}
23
24pub(crate) struct Parser<'a> {
26 parser: RawParser<'a>,
27}
28
29#[derive(Default)]
31pub(crate) struct ParserBuilder<'a> {
32 psess: Option<&'a ParseSess>,
33 input: Option<Input>,
34}
35
36impl<'a> ParserBuilder<'a> {
37 pub(crate) fn input(mut self, input: Input) -> ParserBuilder<'a> {
38 self.input = Some(input);
39 self
40 }
41
42 pub(crate) fn psess(mut self, psess: &'a ParseSess) -> ParserBuilder<'a> {
43 self.psess = Some(psess);
44 self
45 }
46
47 pub(crate) fn build(self) -> Result<Parser<'a>, ParserError> {
48 let psess = self.psess.ok_or(ParserError::NoParseSess)?;
49 let input = self.input.ok_or(ParserError::NoInput)?;
50
51 let parser = match Self::parser(psess.inner(), input) {
52 Ok(p) => p,
53 Err(diagnostics) => {
54 psess.emit_diagnostics(diagnostics);
55 return Err(ParserError::ParserCreationError);
56 }
57 };
58
59 Ok(Parser { parser })
60 }
61
62 fn parser(
63 psess: &'a rustc_session::parse::ParseSess,
64 input: Input,
65 ) -> Result<RawParser<'a>, Vec<Diag<'a>>> {
66 match input {
67 Input::File(ref file) => new_parser_from_file(psess, file, None),
68 Input::Text(text) => new_parser_from_source_str(
69 psess,
70 rustc_span::FileName::Custom("stdin".to_owned()),
71 text,
72 ),
73 }
74 }
75}
76
77#[derive(Debug, PartialEq)]
78pub(crate) enum ParserError {
79 NoParseSess,
80 NoInput,
81 ParserCreationError,
82 ParseError,
83 ParsePanicError,
84}
85
86impl<'a> Parser<'a> {
87 pub(crate) fn submod_path_from_attr(attrs: &[ast::Attribute], path: &Path) -> Option<PathBuf> {
88 let path_sym = attr::first_attr_value_str_by_name(attrs, sym::path)?;
89 let path_str = path_sym.as_str();
90
91 #[cfg(windows)]
96 let path_str = path_str.replace("/", "\\");
97
98 Some(path.join(path_str))
99 }
100
101 pub(crate) fn parse_file_as_module(
102 psess: &'a ParseSess,
103 path: &Path,
104 span: Span,
105 ) -> Result<(ast::AttrVec, ThinVec<ptr::P<ast::Item>>, Span), ParserError> {
106 let result = catch_unwind(AssertUnwindSafe(|| {
107 let mut parser =
108 unwrap_or_emit_fatal(new_parser_from_file(psess.inner(), path, Some(span)));
109 match parser.parse_mod(exp!(Eof)) {
110 Ok((a, i, spans)) => Some((a, i, spans.inner_span)),
111 Err(e) => {
112 e.emit();
113 if psess.can_reset_errors() {
114 psess.reset_errors();
115 }
116 None
117 }
118 }
119 }));
120 match result {
121 Ok(Some(m)) if !psess.has_errors() => Ok(m),
122 Ok(Some(m)) if psess.can_reset_errors() => {
123 psess.reset_errors();
124 Ok(m)
125 }
126 Ok(_) => Err(ParserError::ParseError),
127 Err(..) if path.exists() => Err(ParserError::ParseError),
128 Err(_) => Err(ParserError::ParsePanicError),
129 }
130 }
131
132 pub(crate) fn parse_crate(
133 input: Input,
134 psess: &'a ParseSess,
135 ) -> Result<ast::Crate, ParserError> {
136 let krate = Parser::parse_crate_inner(input, psess)?;
137 if !psess.has_errors() {
138 return Ok(krate);
139 }
140
141 if psess.can_reset_errors() {
142 psess.reset_errors();
143 return Ok(krate);
144 }
145
146 Err(ParserError::ParseError)
147 }
148
149 fn parse_crate_inner(input: Input, psess: &'a ParseSess) -> Result<ast::Crate, ParserError> {
150 ParserBuilder::default()
151 .input(input)
152 .psess(psess)
153 .build()?
154 .parse_crate_mod()
155 }
156
157 fn parse_crate_mod(&mut self) -> Result<ast::Crate, ParserError> {
158 let mut parser = AssertUnwindSafe(&mut self.parser);
159 let err = Err(ParserError::ParsePanicError);
160 match catch_unwind(move || parser.parse_crate_mod()) {
161 Ok(Ok(k)) => Ok(k),
162 Ok(Err(db)) => {
163 db.emit();
164 err
165 }
166 Err(_) => err,
167 }
168 }
169}