Unnamed repository; edit this file 'description' to name the repository.
3 files changed, 165 insertions, 17 deletions
diff --git a/crates/parser/src/grammar/expressions/atom.rs b/crates/parser/src/grammar/expressions/atom.rs index 72848a1f2b..54ed5f0ba2 100644 --- a/crates/parser/src/grammar/expressions/atom.rs +++ b/crates/parser/src/grammar/expressions/atom.rs @@ -490,6 +490,18 @@ fn match_expr(p: &mut Parser<'_>) -> CompletedMarker { m.complete(p, MATCH_EXPR) } +// test_err match_arms_recovery +// fn foo() { +// match () { +// _ => (),, +// _ => , +// _ => (), +// => (), +// if true => (), +// _ => (), +// () if => (), +// } +// } pub(crate) fn match_arm_list(p: &mut Parser<'_>) { assert!(p.at(T!['{'])); let m = p.start(); @@ -511,6 +523,10 @@ pub(crate) fn match_arm_list(p: &mut Parser<'_>) { error_block(p, "expected match arm"); continue; } + if p.at(T![,]) { + p.err_and_bump("expected pattern"); + continue; + } match_arm(p); } p.expect(T!['}']); @@ -544,26 +560,30 @@ fn match_arm(p: &mut Parser<'_>) { // } attributes::outer_attrs(p); - patterns::pattern_top_r(p, TokenSet::EMPTY); + patterns::pattern_top_r(p, TokenSet::new(&[T![=], T![if]])); if p.at(T![if]) { match_guard(p); } p.expect(T![=>]); - let blocklike = match expr_stmt(p, None) { - Some((_, blocklike)) => blocklike, - None => BlockLike::NotBlock, - }; - - // test match_arms_commas - // fn foo() { - // match () { - // _ => (), - // _ => {} - // _ => () - // } - // } - if !p.eat(T![,]) && !blocklike.is_block() && !p.at(T!['}']) { - p.error("expected `,`"); + if p.eat(T![,]) { + p.error("expected expression"); + } else { + let blocklike = match expr_stmt(p, None) { + Some((_, blocklike)) => blocklike, + None => BlockLike::NotBlock, + }; + + // test match_arms_commas + // fn foo() { + // match () { + // _ => (), + // _ => {} + // _ => () + // } + // } + if !p.eat(T![,]) && !blocklike.is_block() && !p.at(T!['}']) { + p.error("expected `,`"); + } } m.complete(p, MATCH_ARM); } @@ -579,7 +599,11 @@ fn match_guard(p: &mut Parser<'_>) -> CompletedMarker { assert!(p.at(T![if])); let m = p.start(); p.bump(T![if]); - expr(p); + if p.at(T![=]) { + p.error("expected expression"); + } else { + expr(p); + } m.complete(p, MATCH_GUARD) } diff --git a/crates/parser/test_data/parser/inline/err/0034_match_arms_recovery.rast b/crates/parser/test_data/parser/inline/err/0034_match_arms_recovery.rast new file mode 100644 index 0000000000..5b191945e4 --- /dev/null +++ b/crates/parser/test_data/parser/inline/err/0034_match_arms_recovery.rast @@ -0,0 +1,113 @@ +SOURCE_FILE + FN + FN_KW "fn" + WHITESPACE " " + NAME + IDENT "foo" + PARAM_LIST + L_PAREN "(" + R_PAREN ")" + WHITESPACE " " + BLOCK_EXPR + STMT_LIST + L_CURLY "{" + WHITESPACE "\n " + MATCH_EXPR + MATCH_KW "match" + WHITESPACE " " + TUPLE_EXPR + L_PAREN "(" + R_PAREN ")" + WHITESPACE " " + MATCH_ARM_LIST + L_CURLY "{" + WHITESPACE "\n " + MATCH_ARM + WILDCARD_PAT + UNDERSCORE "_" + WHITESPACE " " + FAT_ARROW "=>" + WHITESPACE " " + TUPLE_EXPR + L_PAREN "(" + R_PAREN ")" + COMMA "," + ERROR + COMMA "," + WHITESPACE "\n " + MATCH_ARM + WILDCARD_PAT + UNDERSCORE "_" + WHITESPACE " " + FAT_ARROW "=>" + WHITESPACE " " + COMMA "," + WHITESPACE "\n " + MATCH_ARM + WILDCARD_PAT + UNDERSCORE "_" + WHITESPACE " " + FAT_ARROW "=>" + WHITESPACE " " + TUPLE_EXPR + L_PAREN "(" + R_PAREN ")" + COMMA "," + WHITESPACE "\n " + MATCH_ARM + FAT_ARROW "=>" + WHITESPACE " " + TUPLE_EXPR + L_PAREN "(" + R_PAREN ")" + COMMA "," + WHITESPACE "\n " + MATCH_ARM + MATCH_GUARD + IF_KW "if" + WHITESPACE " " + LITERAL + TRUE_KW "true" + WHITESPACE " " + FAT_ARROW "=>" + WHITESPACE " " + TUPLE_EXPR + L_PAREN "(" + R_PAREN ")" + COMMA "," + WHITESPACE "\n " + MATCH_ARM + WILDCARD_PAT + UNDERSCORE "_" + WHITESPACE " " + FAT_ARROW "=>" + WHITESPACE " " + TUPLE_EXPR + L_PAREN "(" + R_PAREN ")" + COMMA "," + WHITESPACE "\n " + MATCH_ARM + TUPLE_PAT + L_PAREN "(" + R_PAREN ")" + WHITESPACE " " + MATCH_GUARD + IF_KW "if" + WHITESPACE " " + FAT_ARROW "=>" + WHITESPACE " " + TUPLE_EXPR + L_PAREN "(" + R_PAREN ")" + COMMA "," + WHITESPACE "\n " + R_CURLY "}" + WHITESPACE "\n" + R_CURLY "}" + WHITESPACE "\n" +error 42: expected pattern +error 58: expected expression +error 85: expected pattern +error 100: expected pattern +error 145: expected expression diff --git a/crates/parser/test_data/parser/inline/err/0034_match_arms_recovery.rs b/crates/parser/test_data/parser/inline/err/0034_match_arms_recovery.rs new file mode 100644 index 0000000000..173103b2e3 --- /dev/null +++ b/crates/parser/test_data/parser/inline/err/0034_match_arms_recovery.rs @@ -0,0 +1,11 @@ +fn foo() { + match () { + _ => (),, + _ => , + _ => (), + => (), + if true => (), + _ => (), + () if => (), + } +} |