aboutsummaryrefslogtreecommitdiff
path: root/crates/ra_mbe
diff options
context:
space:
mode:
Diffstat (limited to 'crates/ra_mbe')
-rw-r--r--crates/ra_mbe/src/lib.rs177
-rw-r--r--crates/ra_mbe/src/mbe_expander.rs36
-rw-r--r--crates/ra_mbe/src/subtree_parser.rs12
-rw-r--r--crates/ra_mbe/src/syntax_bridge.rs71
-rw-r--r--crates/ra_mbe/src/tt_cursor.rs40
5 files changed, 325 insertions, 11 deletions
diff --git a/crates/ra_mbe/src/lib.rs b/crates/ra_mbe/src/lib.rs
index 8d5008d20..d2115bd67 100644
--- a/crates/ra_mbe/src/lib.rs
+++ b/crates/ra_mbe/src/lib.rs
@@ -37,9 +37,19 @@ pub enum ExpandError {
37 NoMatchingRule, 37 NoMatchingRule,
38 UnexpectedToken, 38 UnexpectedToken,
39 BindingError(String), 39 BindingError(String),
40 ConversionError,
40} 41}
41 42
42pub use crate::syntax_bridge::{ast_to_token_tree, token_tree_to_ast_item_list, syntax_node_to_token_tree}; 43pub use crate::syntax_bridge::{
44 ast_to_token_tree,
45 token_tree_to_ast_item_list,
46 syntax_node_to_token_tree,
47 token_tree_to_expr,
48 token_tree_to_pat,
49 token_tree_to_ty,
50 token_tree_to_macro_items,
51 token_tree_to_macro_stmts,
52};
43 53
44/// This struct contains AST for a single `macro_rules` definition. What might 54/// This struct contains AST for a single `macro_rules` definition. What might
45/// be very confusing is that AST has almost exactly the same shape as 55/// be very confusing is that AST has almost exactly the same shape as
@@ -192,23 +202,26 @@ impl_froms!(TokenTree: Leaf, Subtree);
192 pub(crate) fn expand_to_syntax( 202 pub(crate) fn expand_to_syntax(
193 rules: &MacroRules, 203 rules: &MacroRules,
194 invocation: &str, 204 invocation: &str,
195 ) -> ra_syntax::TreeArc<ast::SourceFile> { 205 ) -> ra_syntax::TreeArc<ast::MacroItems> {
196 let expanded = expand(rules, invocation); 206 let expanded = expand(rules, invocation);
197 token_tree_to_ast_item_list(&expanded) 207 token_tree_to_macro_items(&expanded).unwrap()
198 } 208 }
199 209
200 pub(crate) fn assert_expansion(rules: &MacroRules, invocation: &str, expansion: &str) { 210 pub(crate) fn assert_expansion(rules: &MacroRules, invocation: &str, expansion: &str) {
201 let expanded = expand(rules, invocation); 211 let expanded = expand(rules, invocation);
202 assert_eq!(expanded.to_string(), expansion); 212 assert_eq!(expanded.to_string(), expansion);
203 213
204 let tree = token_tree_to_ast_item_list(&expanded); 214 let tree = token_tree_to_macro_items(&expanded);
205 215
206 // Eat all white space by parse it back and forth 216 // Eat all white space by parse it back and forth
207 let expansion = ast::SourceFile::parse(expansion); 217 let expansion = ast::SourceFile::parse(expansion);
208 let expansion = syntax_node_to_token_tree(expansion.syntax()).unwrap().0; 218 let expansion = syntax_node_to_token_tree(expansion.syntax()).unwrap().0;
209 let file = token_tree_to_ast_item_list(&expansion); 219 let file = token_tree_to_macro_items(&expansion);
210 220
211 assert_eq!(tree.syntax().debug_dump().trim(), file.syntax().debug_dump().trim()); 221 assert_eq!(
222 tree.unwrap().syntax().debug_dump().trim(),
223 file.unwrap().syntax().debug_dump().trim()
224 );
212 } 225 }
213 226
214 #[test] 227 #[test]
@@ -346,11 +359,11 @@ impl_froms!(TokenTree: Leaf, Subtree);
346 ", 359 ",
347 ); 360 );
348 let expansion = expand(&rules, "structs!(Foo, Bar)"); 361 let expansion = expand(&rules, "structs!(Foo, Bar)");
349 let tree = token_tree_to_ast_item_list(&expansion); 362 let tree = token_tree_to_macro_items(&expansion);
350 assert_eq!( 363 assert_eq!(
351 tree.syntax().debug_dump().trim(), 364 tree.unwrap().syntax().debug_dump().trim(),
352 r#" 365 r#"
353SOURCE_FILE@[0; 40) 366MACRO_ITEMS@[0; 40)
354 STRUCT_DEF@[0; 20) 367 STRUCT_DEF@[0; 20)
355 STRUCT_KW@[0; 6) "struct" 368 STRUCT_KW@[0; 6) "struct"
356 NAME@[6; 9) 369 NAME@[6; 9)
@@ -444,6 +457,59 @@ SOURCE_FILE@[0; 40)
444 assert_expansion(&rules, "foo! { foo, bar }", "fn foo () {let a = foo ; let b = bar ;}"); 457 assert_expansion(&rules, "foo! { foo, bar }", "fn foo () {let a = foo ; let b = bar ;}");
445 } 458 }
446 459
460 #[test]
461 fn test_tt_to_stmts() {
462 let rules = create_rules(
463 r#"
464 macro_rules! foo {
465 () => {
466 let a = 0;
467 a = 10 + 1;
468 a
469 }
470 }
471"#,
472 );
473
474 let expanded = expand(&rules, "foo!{}");
475 let stmts = token_tree_to_macro_stmts(&expanded);
476
477 assert_eq!(
478 stmts.unwrap().syntax().debug_dump().trim(),
479 r#"MACRO_STMTS@[0; 15)
480 LET_STMT@[0; 7)
481 LET_KW@[0; 3) "let"
482 BIND_PAT@[3; 4)
483 NAME@[3; 4)
484 IDENT@[3; 4) "a"
485 EQ@[4; 5) "="
486 LITERAL@[5; 6)
487 INT_NUMBER@[5; 6) "0"
488 SEMI@[6; 7) ";"
489 EXPR_STMT@[7; 14)
490 BIN_EXPR@[7; 13)
491 PATH_EXPR@[7; 8)
492 PATH@[7; 8)
493 PATH_SEGMENT@[7; 8)
494 NAME_REF@[7; 8)
495 IDENT@[7; 8) "a"
496 EQ@[8; 9) "="
497 BIN_EXPR@[9; 13)
498 LITERAL@[9; 11)
499 INT_NUMBER@[9; 11) "10"
500 PLUS@[11; 12) "+"
501 LITERAL@[12; 13)
502 INT_NUMBER@[12; 13) "1"
503 SEMI@[13; 14) ";"
504 EXPR_STMT@[14; 15)
505 PATH_EXPR@[14; 15)
506 PATH@[14; 15)
507 PATH_SEGMENT@[14; 15)
508 NAME_REF@[14; 15)
509 IDENT@[14; 15) "a""#,
510 );
511 }
512
447 // The following tests are port from intellij-rust directly 513 // The following tests are port from intellij-rust directly
448 // https://github.com/intellij-rust/intellij-rust/blob/c4e9feee4ad46e7953b1948c112533360b6087bb/src/test/kotlin/org/rust/lang/core/macros/RsMacroExpansionTest.kt 514 // https://github.com/intellij-rust/intellij-rust/blob/c4e9feee4ad46e7953b1948c112533360b6087bb/src/test/kotlin/org/rust/lang/core/macros/RsMacroExpansionTest.kt
449 515
@@ -527,7 +593,7 @@ SOURCE_FILE@[0; 40)
527 593
528 assert_eq!( 594 assert_eq!(
529 expand_to_syntax(&rules, "foo! { 1 + 1 }").syntax().debug_dump().trim(), 595 expand_to_syntax(&rules, "foo! { 1 + 1 }").syntax().debug_dump().trim(),
530 r#"SOURCE_FILE@[0; 15) 596 r#"MACRO_ITEMS@[0; 15)
531 FN_DEF@[0; 15) 597 FN_DEF@[0; 15)
532 FN_KW@[0; 2) "fn" 598 FN_KW@[0; 2) "fn"
533 NAME@[2; 5) 599 NAME@[2; 5)
@@ -665,4 +731,95 @@ SOURCE_FILE@[0; 40)
665 } 731 }
666"#, r#"extern crate a ; mod b ; mod c {} use d ; const E : i32 = 0 ; static F : i32 = 0 ; impl G {} struct H ; enum I {Foo} trait J {} fn h () {} extern {} type T = u8 ;"#); 732"#, r#"extern crate a ; mod b ; mod c {} use d ; const E : i32 = 0 ; static F : i32 = 0 ; impl G {} struct H ; enum I {Foo} trait J {} fn h () {} extern {} type T = u8 ;"#);
667 } 733 }
734
735 #[test]
736 fn test_block() {
737 let rules = create_rules(
738 r#"
739 macro_rules! foo {
740 ($ i:block) => { fn foo() $ i }
741 }
742"#,
743 );
744 assert_expansion(&rules, "foo! { { 1; } }", "fn foo () {1 ;}");
745 }
746
747 #[test]
748 fn test_meta() {
749 let rules = create_rules(
750 r#"
751 macro_rules! foo {
752 ($ i:meta) => (
753 #[$ i]
754 fn bar() {}
755 )
756 }
757"#,
758 );
759 assert_expansion(
760 &rules,
761 r#"foo! { cfg(target_os = "windows") }"#,
762 r#"# [cfg (target_os = "windows")] fn bar () {}"#,
763 );
764 }
765
766 // #[test]
767 // fn test_tt_block() {
768 // let rules = create_rules(
769 // r#"
770 // macro_rules! foo {
771 // ($ i:tt) => { fn foo() $ i }
772 // }
773 // "#,
774 // );
775 // assert_expansion(&rules, r#"foo! { { 1; } }"#, r#"fn foo () {1 ;}"#);
776 // }
777
778 // #[test]
779 // fn test_tt_group() {
780 // let rules = create_rules(
781 // r#"
782 // macro_rules! foo {
783 // ($($ i:tt)*) => { $($ i)* }
784 // }
785 // "#,
786 // );
787 // assert_expansion(&rules, r#"foo! { fn foo() {} }"#, r#"fn foo () {}"#);
788 // }
789
790 #[test]
791 fn test_lifetime() {
792 let rules = create_rules(
793 r#"
794 macro_rules! foo {
795 ($ lt:lifetime) => { struct Ref<$ lt>{ s: &$ lt str } }
796 }
797"#,
798 );
799 assert_expansion(&rules, r#"foo!{'a}"#, r#"struct Ref < 'a > {s : & 'a str}"#);
800 }
801
802 #[test]
803 fn test_literal() {
804 let rules = create_rules(
805 r#"
806 macro_rules! foo {
807 ($ type:ty $ lit:literal) => { const VALUE: $ type = $ lit;};
808 }
809"#,
810 );
811 assert_expansion(&rules, r#"foo!(u8 0)"#, r#"const VALUE : u8 = 0 ;"#);
812 }
813
814 #[test]
815 fn test_vis() {
816 let rules = create_rules(
817 r#"
818 macro_rules! foo {
819 ($ vis:vis $ name:ident) => { $ vis fn $ name() {}};
820 }
821"#,
822 );
823 assert_expansion(&rules, r#"foo!(pub foo);"#, r#"pub fn foo () {}"#);
824 }
668} 825}
diff --git a/crates/ra_mbe/src/mbe_expander.rs b/crates/ra_mbe/src/mbe_expander.rs
index acba42809..86867111f 100644
--- a/crates/ra_mbe/src/mbe_expander.rs
+++ b/crates/ra_mbe/src/mbe_expander.rs
@@ -161,11 +161,47 @@ fn match_lhs(pattern: &crate::Subtree, input: &mut TtCursor) -> Result<Bindings,
161 let pat = input.eat_stmt().ok_or(ExpandError::UnexpectedToken)?.clone(); 161 let pat = input.eat_stmt().ok_or(ExpandError::UnexpectedToken)?.clone();
162 res.inner.insert(text.clone(), Binding::Simple(pat.into())); 162 res.inner.insert(text.clone(), Binding::Simple(pat.into()));
163 } 163 }
164 "block" => {
165 let block =
166 input.eat_block().ok_or(ExpandError::UnexpectedToken)?.clone();
167 res.inner.insert(text.clone(), Binding::Simple(block.into()));
168 }
169 "meta" => {
170 let meta =
171 input.eat_meta().ok_or(ExpandError::UnexpectedToken)?.clone();
172 res.inner.insert(text.clone(), Binding::Simple(meta.into()));
173 }
174 // FIXME:
175 // Enable followiing code when everything is fixed
176 // At least we can dogfood itself to not stackoverflow
177 //
178 // "tt" => {
179 // let token = input.eat().ok_or(ExpandError::UnexpectedToken)?.clone();
180 // res.inner.insert(text.clone(), Binding::Simple(token.into()));
181 // }
164 "item" => { 182 "item" => {
165 let item = 183 let item =
166 input.eat_item().ok_or(ExpandError::UnexpectedToken)?.clone(); 184 input.eat_item().ok_or(ExpandError::UnexpectedToken)?.clone();
167 res.inner.insert(text.clone(), Binding::Simple(item.into())); 185 res.inner.insert(text.clone(), Binding::Simple(item.into()));
168 } 186 }
187 "lifetime" => {
188 let lifetime =
189 input.eat_lifetime().ok_or(ExpandError::UnexpectedToken)?.clone();
190 res.inner.insert(text.clone(), Binding::Simple(lifetime.into()));
191 }
192 "literal" => {
193 let literal =
194 input.eat_literal().ok_or(ExpandError::UnexpectedToken)?.clone();
195 res.inner.insert(
196 text.clone(),
197 Binding::Simple(tt::Leaf::from(literal).into()),
198 );
199 }
200 "vis" => {
201 let vis = input.eat_vis().ok_or(ExpandError::UnexpectedToken)?.clone();
202 res.inner.insert(text.clone(), Binding::Simple(vis.into()));
203 }
204
169 _ => return Err(ExpandError::UnexpectedToken), 205 _ => return Err(ExpandError::UnexpectedToken),
170 } 206 }
171 } 207 }
diff --git a/crates/ra_mbe/src/subtree_parser.rs b/crates/ra_mbe/src/subtree_parser.rs
index 195e4c3ac..528aa0f8a 100644
--- a/crates/ra_mbe/src/subtree_parser.rs
+++ b/crates/ra_mbe/src/subtree_parser.rs
@@ -46,10 +46,22 @@ impl<'a> Parser<'a> {
46 self.parse(|src, sink| ra_parser::parse_stmt(src, sink, false)) 46 self.parse(|src, sink| ra_parser::parse_stmt(src, sink, false))
47 } 47 }
48 48
49 pub fn parse_block(self) -> Option<tt::TokenTree> {
50 self.parse(ra_parser::parse_block)
51 }
52
53 pub fn parse_meta(self) -> Option<tt::TokenTree> {
54 self.parse(ra_parser::parse_meta)
55 }
56
49 pub fn parse_item(self) -> Option<tt::TokenTree> { 57 pub fn parse_item(self) -> Option<tt::TokenTree> {
50 self.parse(ra_parser::parse_item) 58 self.parse(ra_parser::parse_item)
51 } 59 }
52 60
61 pub fn parse_vis(self) -> Option<tt::TokenTree> {
62 self.parse(ra_parser::parse_vis)
63 }
64
53 fn parse<F>(self, f: F) -> Option<tt::TokenTree> 65 fn parse<F>(self, f: F) -> Option<tt::TokenTree>
54 where 66 where
55 F: FnOnce(&dyn TokenSource, &mut dyn TreeSink), 67 F: FnOnce(&dyn TokenSource, &mut dyn TreeSink),
diff --git a/crates/ra_mbe/src/syntax_bridge.rs b/crates/ra_mbe/src/syntax_bridge.rs
index 28ded7870..38a481029 100644
--- a/crates/ra_mbe/src/syntax_bridge.rs
+++ b/crates/ra_mbe/src/syntax_bridge.rs
@@ -5,6 +5,7 @@ use ra_syntax::{
5}; 5};
6 6
7use crate::subtree_source::{SubtreeTokenSource, Querier}; 7use crate::subtree_source::{SubtreeTokenSource, Querier};
8use crate::ExpandError;
8 9
9/// Maps `tt::TokenId` to the relative range of the original token. 10/// Maps `tt::TokenId` to the relative range of the original token.
10#[derive(Default)] 11#[derive(Default)]
@@ -30,6 +31,71 @@ pub fn syntax_node_to_token_tree(node: &SyntaxNode) -> Option<(tt::Subtree, Toke
30 Some((tt, token_map)) 31 Some((tt, token_map))
31} 32}
32 33
34// The following items are what `rustc` macro can be parsed into :
35// link: https://github.com/rust-lang/rust/blob/9ebf47851a357faa4cd97f4b1dc7835f6376e639/src/libsyntax/ext/expand.rs#L141
36// * Expr(P<ast::Expr>) -> token_tree_to_expr
37// * Pat(P<ast::Pat>) -> token_tree_to_pat
38// * Ty(P<ast::Ty>) -> token_tree_to_ty
39// * Stmts(SmallVec<[ast::Stmt; 1]>) -> token_tree_to_stmts
40// * Items(SmallVec<[P<ast::Item>; 1]>) -> token_tree_to_items
41//
42// * TraitItems(SmallVec<[ast::TraitItem; 1]>)
43// * ImplItems(SmallVec<[ast::ImplItem; 1]>)
44// * ForeignItems(SmallVec<[ast::ForeignItem; 1]>
45//
46//
47
48/// Parses the token tree (result of macro expansion) to an expression
49pub fn token_tree_to_expr(tt: &tt::Subtree) -> Result<TreeArc<ast::Expr>, ExpandError> {
50 let token_source = SubtreeTokenSource::new(tt);
51 let mut tree_sink = TtTreeSink::new(token_source.querier());
52 ra_parser::parse_expr(&token_source, &mut tree_sink);
53 let syntax = tree_sink.inner.finish();
54 ast::Expr::cast(&syntax)
55 .map(|m| m.to_owned())
56 .ok_or_else(|| crate::ExpandError::ConversionError)
57}
58
59/// Parses the token tree (result of macro expansion) to a Pattern
60pub fn token_tree_to_pat(tt: &tt::Subtree) -> Result<TreeArc<ast::Pat>, ExpandError> {
61 let token_source = SubtreeTokenSource::new(tt);
62 let mut tree_sink = TtTreeSink::new(token_source.querier());
63 ra_parser::parse_pat(&token_source, &mut tree_sink);
64 let syntax = tree_sink.inner.finish();
65 ast::Pat::cast(&syntax).map(|m| m.to_owned()).ok_or_else(|| ExpandError::ConversionError)
66}
67
68/// Parses the token tree (result of macro expansion) to a Type
69pub fn token_tree_to_ty(tt: &tt::Subtree) -> Result<TreeArc<ast::TypeRef>, ExpandError> {
70 let token_source = SubtreeTokenSource::new(tt);
71 let mut tree_sink = TtTreeSink::new(token_source.querier());
72 ra_parser::parse_ty(&token_source, &mut tree_sink);
73 let syntax = tree_sink.inner.finish();
74 ast::TypeRef::cast(&syntax).map(|m| m.to_owned()).ok_or_else(|| ExpandError::ConversionError)
75}
76
77/// Parses the token tree (result of macro expansion) as a sequence of stmts
78pub fn token_tree_to_macro_stmts(
79 tt: &tt::Subtree,
80) -> Result<TreeArc<ast::MacroStmts>, ExpandError> {
81 let token_source = SubtreeTokenSource::new(tt);
82 let mut tree_sink = TtTreeSink::new(token_source.querier());
83 ra_parser::parse_macro_stmts(&token_source, &mut tree_sink);
84 let syntax = tree_sink.inner.finish();
85 ast::MacroStmts::cast(&syntax).map(|m| m.to_owned()).ok_or_else(|| ExpandError::ConversionError)
86}
87
88/// Parses the token tree (result of macro expansion) as a sequence of items
89pub fn token_tree_to_macro_items(
90 tt: &tt::Subtree,
91) -> Result<TreeArc<ast::MacroItems>, ExpandError> {
92 let token_source = SubtreeTokenSource::new(tt);
93 let mut tree_sink = TtTreeSink::new(token_source.querier());
94 ra_parser::parse_macro_items(&token_source, &mut tree_sink);
95 let syntax = tree_sink.inner.finish();
96 ast::MacroItems::cast(&syntax).map(|m| m.to_owned()).ok_or_else(|| ExpandError::ConversionError)
97}
98
33/// Parses the token tree (result of macro expansion) as a sequence of items 99/// Parses the token tree (result of macro expansion) as a sequence of items
34pub fn token_tree_to_ast_item_list(tt: &tt::Subtree) -> TreeArc<ast::SourceFile> { 100pub fn token_tree_to_ast_item_list(tt: &tt::Subtree) -> TreeArc<ast::SourceFile> {
35 let token_source = SubtreeTokenSource::new(tt); 101 let token_source = SubtreeTokenSource::new(tt);
@@ -91,7 +157,10 @@ fn convert_tt(
91 ); 157 );
92 } 158 }
93 } else { 159 } else {
94 let child = if token.kind().is_keyword() || token.kind() == IDENT { 160 let child: tt::TokenTree = if token.kind().is_keyword()
161 || token.kind() == IDENT
162 || token.kind() == LIFETIME
163 {
95 let relative_range = token.range() - global_offset; 164 let relative_range = token.range() - global_offset;
96 let id = token_map.alloc(relative_range); 165 let id = token_map.alloc(relative_range);
97 let text = token.text().clone(); 166 let text = token.text().clone();
diff --git a/crates/ra_mbe/src/tt_cursor.rs b/crates/ra_mbe/src/tt_cursor.rs
index 484437b0e..741b5ea1c 100644
--- a/crates/ra_mbe/src/tt_cursor.rs
+++ b/crates/ra_mbe/src/tt_cursor.rs
@@ -41,6 +41,13 @@ impl<'a> TtCursor<'a> {
41 } 41 }
42 } 42 }
43 43
44 pub(crate) fn at_literal(&mut self) -> Option<&'a tt::Literal> {
45 match self.current() {
46 Some(tt::TokenTree::Leaf(tt::Leaf::Literal(i))) => Some(i),
47 _ => None,
48 }
49 }
50
44 pub(crate) fn bump(&mut self) { 51 pub(crate) fn bump(&mut self) {
45 self.pos += 1; 52 self.pos += 1;
46 } 53 }
@@ -79,6 +86,13 @@ impl<'a> TtCursor<'a> {
79 }) 86 })
80 } 87 }
81 88
89 pub(crate) fn eat_literal(&mut self) -> Option<&'a tt::Literal> {
90 self.at_literal().map(|i| {
91 self.bump();
92 i
93 })
94 }
95
82 pub(crate) fn eat_path(&mut self) -> Option<tt::TokenTree> { 96 pub(crate) fn eat_path(&mut self) -> Option<tt::TokenTree> {
83 let parser = Parser::new(&mut self.pos, self.subtree); 97 let parser = Parser::new(&mut self.pos, self.subtree);
84 parser.parse_path() 98 parser.parse_path()
@@ -104,11 +118,37 @@ impl<'a> TtCursor<'a> {
104 parser.parse_stmt() 118 parser.parse_stmt()
105 } 119 }
106 120
121 pub(crate) fn eat_block(&mut self) -> Option<tt::TokenTree> {
122 let parser = Parser::new(&mut self.pos, self.subtree);
123 parser.parse_block()
124 }
125
126 pub(crate) fn eat_meta(&mut self) -> Option<tt::TokenTree> {
127 let parser = Parser::new(&mut self.pos, self.subtree);
128 parser.parse_meta()
129 }
130
107 pub(crate) fn eat_item(&mut self) -> Option<tt::TokenTree> { 131 pub(crate) fn eat_item(&mut self) -> Option<tt::TokenTree> {
108 let parser = Parser::new(&mut self.pos, self.subtree); 132 let parser = Parser::new(&mut self.pos, self.subtree);
109 parser.parse_item() 133 parser.parse_item()
110 } 134 }
111 135
136 pub(crate) fn eat_lifetime(&mut self) -> Option<tt::TokenTree> {
137 // check if it start from "`"
138 if let Some(ident) = self.at_ident() {
139 if ident.text.chars().next()? != '\'' {
140 return None;
141 }
142 }
143
144 self.eat_ident().cloned().map(|ident| tt::Leaf::from(ident).into())
145 }
146
147 pub(crate) fn eat_vis(&mut self) -> Option<tt::TokenTree> {
148 let parser = Parser::new(&mut self.pos, self.subtree);
149 parser.parse_vis()
150 }
151
112 pub(crate) fn expect_char(&mut self, char: char) -> Result<(), ParseError> { 152 pub(crate) fn expect_char(&mut self, char: char) -> Result<(), ParseError> {
113 if self.at_char(char) { 153 if self.at_char(char) {
114 self.bump(); 154 self.bump();