From 7c67612b8a894187fa3b64725531a5459f9211bf Mon Sep 17 00:00:00 2001 From: Aleksey Kladov Date: Fri, 10 Aug 2018 22:33:29 +0300 Subject: organizize --- crates/libsyntax2/src/grammar/attributes.rs | 79 +++++ crates/libsyntax2/src/grammar/expressions/atom.rs | 348 ++++++++++++++++++++ crates/libsyntax2/src/grammar/expressions/mod.rs | 379 ++++++++++++++++++++++ crates/libsyntax2/src/grammar/items/consts.rs | 21 ++ crates/libsyntax2/src/grammar/items/mod.rs | 332 +++++++++++++++++++ crates/libsyntax2/src/grammar/items/structs.rs | 116 +++++++ crates/libsyntax2/src/grammar/items/traits.rs | 87 +++++ crates/libsyntax2/src/grammar/items/use_item.rs | 66 ++++ crates/libsyntax2/src/grammar/mod.rs | 161 +++++++++ crates/libsyntax2/src/grammar/params.rs | 116 +++++++ crates/libsyntax2/src/grammar/paths.rs | 86 +++++ crates/libsyntax2/src/grammar/patterns.rs | 204 ++++++++++++ crates/libsyntax2/src/grammar/type_args.rs | 48 +++ crates/libsyntax2/src/grammar/type_params.rs | 127 ++++++++ crates/libsyntax2/src/grammar/types.rs | 212 ++++++++++++ 15 files changed, 2382 insertions(+) create mode 100644 crates/libsyntax2/src/grammar/attributes.rs create mode 100644 crates/libsyntax2/src/grammar/expressions/atom.rs create mode 100644 crates/libsyntax2/src/grammar/expressions/mod.rs create mode 100644 crates/libsyntax2/src/grammar/items/consts.rs create mode 100644 crates/libsyntax2/src/grammar/items/mod.rs create mode 100644 crates/libsyntax2/src/grammar/items/structs.rs create mode 100644 crates/libsyntax2/src/grammar/items/traits.rs create mode 100644 crates/libsyntax2/src/grammar/items/use_item.rs create mode 100644 crates/libsyntax2/src/grammar/mod.rs create mode 100644 crates/libsyntax2/src/grammar/params.rs create mode 100644 crates/libsyntax2/src/grammar/paths.rs create mode 100644 crates/libsyntax2/src/grammar/patterns.rs create mode 100644 crates/libsyntax2/src/grammar/type_args.rs create mode 100644 crates/libsyntax2/src/grammar/type_params.rs create mode 100644 crates/libsyntax2/src/grammar/types.rs (limited to 'crates/libsyntax2/src/grammar') diff --git a/crates/libsyntax2/src/grammar/attributes.rs b/crates/libsyntax2/src/grammar/attributes.rs new file mode 100644 index 000000000..c411d4d7f --- /dev/null +++ b/crates/libsyntax2/src/grammar/attributes.rs @@ -0,0 +1,79 @@ +use super::*; + +pub(super) fn inner_attributes(p: &mut Parser) { + while p.current() == POUND && p.nth(1) == EXCL { + attribute(p, true) + } +} + +pub(super) fn outer_attributes(p: &mut Parser) { + while p.at(POUND) { + attribute(p, false) + } +} + +fn attribute(p: &mut Parser, inner: bool) { + let attr = p.start(); + assert!(p.at(POUND)); + p.bump(); + + if inner { + assert!(p.at(EXCL)); + p.bump(); + } + + if p.expect(L_BRACK) { + meta_item(p); + p.expect(R_BRACK); + } + attr.complete(p, ATTR); +} + +fn meta_item(p: &mut Parser) { + if p.at(IDENT) { + let meta_item = p.start(); + p.bump(); + match p.current() { + EQ => { + p.bump(); + if expressions::literal(p).is_none() { + p.error("expected literal"); + } + } + L_PAREN => meta_item_arg_list(p), + _ => (), + } + meta_item.complete(p, META_ITEM); + } else { + p.error("expected attribute value"); + } +} + +fn meta_item_arg_list(p: &mut Parser) { + assert!(p.at(L_PAREN)); + p.bump(); + loop { + match p.current() { + EOF | R_PAREN => break, + IDENT => meta_item(p), + c => if expressions::literal(p).is_none() { + let message = "expected attribute"; + + if items::ITEM_FIRST.contains(c) { + p.error(message); + return; + } + + let err = p.start(); + p.error(message); + p.bump(); + err.complete(p, ERROR); + continue; + }, + } + if !p.at(R_PAREN) { + p.expect(COMMA); + } + } + p.expect(R_PAREN); +} diff --git a/crates/libsyntax2/src/grammar/expressions/atom.rs b/crates/libsyntax2/src/grammar/expressions/atom.rs new file mode 100644 index 000000000..af9f47c5e --- /dev/null +++ b/crates/libsyntax2/src/grammar/expressions/atom.rs @@ -0,0 +1,348 @@ +use super::*; + +// test expr_literals +// fn foo() { +// let _ = true; +// let _ = false; +// let _ = 1; +// let _ = 2.0; +// let _ = b'a'; +// let _ = 'b'; +// let _ = "c"; +// let _ = r"d"; +// let _ = b"e"; +// let _ = br"f"; +// } +const LITERAL_FIRST: TokenSet = + token_set![TRUE_KW, FALSE_KW, INT_NUMBER, FLOAT_NUMBER, BYTE, CHAR, + STRING, RAW_STRING, BYTE_STRING, RAW_BYTE_STRING]; + +pub(crate) fn literal(p: &mut Parser) -> Option { + if !LITERAL_FIRST.contains(p.current()) { + return None; + } + let m = p.start(); + p.bump(); + Some(m.complete(p, LITERAL)) +} + +pub(super) const ATOM_EXPR_FIRST: TokenSet = + token_set_union![ + LITERAL_FIRST, + token_set![L_PAREN, PIPE, MOVE_KW, IF_KW, WHILE_KW, MATCH_KW, UNSAFE_KW, L_CURLY, RETURN_KW, + IDENT, SELF_KW, SUPER_KW, COLONCOLON ], + ]; + +pub(super) fn atom_expr(p: &mut Parser, r: Restrictions) -> Option { + match literal(p) { + Some(m) => return Some(m), + None => (), + } + if paths::is_path_start(p) { + return Some(path_expr(p, r)); + } + let la = p.nth(1); + let done = match p.current() { + L_PAREN => tuple_expr(p), + L_BRACK => array_expr(p), + PIPE => lambda_expr(p), + MOVE_KW if la == PIPE => lambda_expr(p), + IF_KW => if_expr(p), + WHILE_KW => while_expr(p), + LOOP_KW => loop_expr(p), + FOR_KW => for_expr(p), + MATCH_KW => match_expr(p), + UNSAFE_KW if la == L_CURLY => block_expr(p), + L_CURLY => block_expr(p), + RETURN_KW => return_expr(p), + _ => { + p.err_and_bump("expected expression"); + return None; + } + }; + Some(done) +} + +// test tuple_expr +// fn foo() { +// (); +// (1); +// (1,); +// } +fn tuple_expr(p: &mut Parser) -> CompletedMarker { + assert!(p.at(L_PAREN)); + let m = p.start(); + p.expect(L_PAREN); + + let mut saw_comma = false; + let mut saw_expr = false; + while !p.at(EOF) && !p.at(R_PAREN) { + saw_expr = true; + expr(p); + if !p.at(R_PAREN) { + saw_comma = true; + p.expect(COMMA); + } + } + p.expect(R_PAREN); + m.complete(p, if saw_expr && !saw_comma { PAREN_EXPR } else { TUPLE_EXPR }) +} + +// test array_expr +// fn foo() { +// []; +// [1]; +// [1, 2,]; +// [1; 2]; +// } +fn array_expr(p: &mut Parser) -> CompletedMarker { + assert!(p.at(L_BRACK)); + let m = p.start(); + p.bump(); + if p.eat(R_BRACK) { + return m.complete(p, ARRAY_EXPR); + } + expr(p); + if p.eat(SEMI) { + expr(p); + p.expect(R_BRACK); + return m.complete(p, ARRAY_EXPR); + } + while !p.at(EOF) && !p.at(R_BRACK) { + p.expect(COMMA); + if !p.at(R_BRACK) { + expr(p); + } + } + p.expect(R_BRACK); + m.complete(p, ARRAY_EXPR) +} + +// test lambda_expr +// fn foo() { +// || (); +// || -> i32 { 92 }; +// |x| x; +// move |x: i32,| x; +// } +fn lambda_expr(p: &mut Parser) -> CompletedMarker { + assert!(p.at(PIPE) || (p.at(MOVE_KW) && p.nth(1) == PIPE)); + let m = p.start(); + p.eat(MOVE_KW); + params::param_list_opt_types(p); + if fn_ret_type(p) { + block(p); + } else { + expr(p); + } + m.complete(p, LAMBDA_EXPR) +} + +// test if_expr +// fn foo() { +// if true {}; +// if true {} else {}; +// if true {} else if false {} else {}; +// if S {}; +// } +fn if_expr(p: &mut Parser) -> CompletedMarker { + assert!(p.at(IF_KW)); + let m = p.start(); + p.bump(); + cond(p); + block(p); + if p.at(ELSE_KW) { + p.bump(); + if p.at(IF_KW) { + if_expr(p); + } else { + block(p); + } + } + m.complete(p, IF_EXPR) +} + +// test while_expr +// fn foo() { +// while true {}; +// while let Some(x) = it.next() {}; +// } +fn while_expr(p: &mut Parser) -> CompletedMarker { + assert!(p.at(WHILE_KW)); + let m = p.start(); + p.bump(); + cond(p); + block(p); + m.complete(p, WHILE_EXPR) +} + +// test loop_expr +// fn foo() { +// loop {}; +// } +fn loop_expr(p: &mut Parser) -> CompletedMarker { + assert!(p.at(LOOP_KW)); + let m = p.start(); + p.bump(); + block(p); + m.complete(p, LOOP_EXPR) +} + +// test for_expr +// fn foo() { +// for x in [] {}; +// } +fn for_expr(p: &mut Parser) -> CompletedMarker { + assert!(p.at(FOR_KW)); + let m = p.start(); + p.bump(); + patterns::pattern(p); + p.expect(IN_KW); + expr_no_struct(p); + block(p); + m.complete(p, FOR_EXPR) +} + +// test cond +// fn foo() { if let Some(_) = None {} } +fn cond(p: &mut Parser) { + if p.eat(LET_KW) { + patterns::pattern(p); + p.expect(EQ); + } + expr_no_struct(p) +} + +// test match_expr +// fn foo() { +// match () { }; +// match S {}; +// } +fn match_expr(p: &mut Parser) -> CompletedMarker { + assert!(p.at(MATCH_KW)); + let m = p.start(); + p.bump(); + expr_no_struct(p); + p.eat(L_CURLY); + while !p.at(EOF) && !p.at(R_CURLY) { + // test match_arms_commas + // fn foo() { + // match () { + // _ => (), + // _ => {} + // _ => () + // } + // } + if match_arm(p).is_block() { + p.eat(COMMA); + } else if !p.at(R_CURLY) { + p.expect(COMMA); + } + } + p.expect(R_CURLY); + m.complete(p, MATCH_EXPR) +} + +// test match_arm +// fn foo() { +// match () { +// _ => (), +// X | Y if Z => (), +// }; +// } +fn match_arm(p: &mut Parser) -> BlockLike { + let m = p.start(); + loop { + patterns::pattern(p); + if !p.eat(PIPE) { + break; + } + } + if p.eat(IF_KW) { + expr_no_struct(p); + } + p.expect(FAT_ARROW); + let ret = expr_stmt(p); + m.complete(p, MATCH_ARM); + ret +} + +// test block_expr +// fn foo() { +// {}; +// unsafe {}; +// } +pub(super) fn block_expr(p: &mut Parser) -> CompletedMarker { + assert!(p.at(L_CURLY) || p.at(UNSAFE_KW) && p.nth(1) == L_CURLY); + let m = p.start(); + p.eat(UNSAFE_KW); + p.bump(); + while !p.at(EOF) && !p.at(R_CURLY) { + match p.current() { + LET_KW => let_stmt(p), + _ => { + // test block_items + // fn a() { fn b() {} } + let m = p.start(); + match items::maybe_item(p) { + items::MaybeItem::Item(kind) => { + m.complete(p, kind); + } + items::MaybeItem::Modifiers => { + m.abandon(p); + p.error("expected an item"); + } + // test pub_expr + // fn foo() { pub 92; } //FIXME + items::MaybeItem::None => { + let is_blocklike = expressions::expr_stmt(p) == BlockLike::Block; + if p.eat(SEMI) || (is_blocklike && !p.at(R_CURLY)) { + m.complete(p, EXPR_STMT); + } else { + m.abandon(p); + } + } + } + } + } + } + p.expect(R_CURLY); + m.complete(p, BLOCK_EXPR) +} + +// test let_stmt; +// fn foo() { +// let a; +// let b: i32; +// let c = 92; +// let d: i32 = 92; +// } +fn let_stmt(p: &mut Parser) { + assert!(p.at(LET_KW)); + let m = p.start(); + p.bump(); + patterns::pattern(p); + if p.at(COLON) { + types::ascription(p); + } + if p.eat(EQ) { + expressions::expr(p); + } + p.expect(SEMI); + m.complete(p, LET_STMT); +} + +// test return_expr +// fn foo() { +// return; +// return 92; +// } +fn return_expr(p: &mut Parser) -> CompletedMarker { + assert!(p.at(RETURN_KW)); + let m = p.start(); + p.bump(); + if EXPR_FIRST.contains(p.current()) { + expr(p); + } + m.complete(p, RETURN_EXPR) +} diff --git a/crates/libsyntax2/src/grammar/expressions/mod.rs b/crates/libsyntax2/src/grammar/expressions/mod.rs new file mode 100644 index 000000000..dcbb1e2a8 --- /dev/null +++ b/crates/libsyntax2/src/grammar/expressions/mod.rs @@ -0,0 +1,379 @@ +mod atom; + +use super::*; +pub(super) use self::atom::literal; + +const EXPR_FIRST: TokenSet = LHS_FIRST; + +pub(super) fn expr(p: &mut Parser) -> BlockLike { + let r = Restrictions { forbid_structs: false, prefer_stmt: false }; + expr_bp(p, r, 1) +} + +pub(super) fn expr_stmt(p: &mut Parser) -> BlockLike { + let r = Restrictions { forbid_structs: false, prefer_stmt: true }; + expr_bp(p, r, 1) +} + +fn expr_no_struct(p: &mut Parser) { + let r = Restrictions { forbid_structs: true, prefer_stmt: false }; + expr_bp(p, r, 1); +} + +// test block +// fn a() {} +// fn b() { let _ = 1; } +// fn c() { 1; 2; } +// fn d() { 1; 2 } +pub(super) fn block(p: &mut Parser) { + if !p.at(L_CURLY) { + p.error("expected block"); + return; + } + atom::block_expr(p); +} + +#[derive(Clone, Copy)] +struct Restrictions { + forbid_structs: bool, + prefer_stmt: bool, +} + +enum Op { + Simple, + Composite(SyntaxKind, u8), +} + +fn current_op(p: &Parser) -> (u8, Op) { + if p.at_compound2(PLUS, EQ) { + return (1, Op::Composite(PLUSEQ, 2)); + } + if p.at_compound2(MINUS, EQ) { + return (1, Op::Composite(MINUSEQ, 2)); + } + if p.at_compound3(L_ANGLE, L_ANGLE, EQ) { + return (1, Op::Composite(SHLEQ, 3)); + } + if p.at_compound3(R_ANGLE, R_ANGLE, EQ) { + return (1, Op::Composite(SHREQ, 3)); + } + if p.at_compound2(PIPE, PIPE) { + return (3, Op::Composite(PIPEPIPE, 2)); + } + if p.at_compound2(AMP, AMP) { + return (4, Op::Composite(AMPAMP, 2)); + } + if p.at_compound2(L_ANGLE, EQ) { + return (5, Op::Composite(LTEQ, 2)); + } + if p.at_compound2(R_ANGLE, EQ) { + return (5, Op::Composite(GTEQ, 2)); + } + if p.at_compound2(L_ANGLE, L_ANGLE) { + return (9, Op::Composite(SHL, 2)); + } + if p.at_compound2(R_ANGLE, R_ANGLE) { + return (9, Op::Composite(SHR, 2)); + } + + let bp = match p.current() { + EQ => 1, + DOTDOT => 2, + EQEQ | NEQ | L_ANGLE | R_ANGLE => 5, + PIPE => 6, + CARET => 7, + AMP => 8, + MINUS | PLUS => 10, + STAR | SLASH | PERCENT => 11, + _ => 0, + }; + (bp, Op::Simple) +} + +// Parses expression with binding power of at least bp. +fn expr_bp(p: &mut Parser, r: Restrictions, bp: u8) -> BlockLike { + let mut lhs = match lhs(p, r) { + Some(lhs) => { + // test stmt_bin_expr_ambiguity + // fn foo() { + // let _ = {1} & 2; + // {1} &2; + // } + if r.prefer_stmt && is_block(lhs.kind()) { + return BlockLike::Block; + } + lhs + } + None => return BlockLike::NotBlock, + }; + + loop { + let is_range = p.current() == DOTDOT; + let (op_bp, op) = current_op(p); + if op_bp < bp { + break; + } + let m = lhs.precede(p); + match op { + Op::Simple => p.bump(), + Op::Composite(kind, n) => { + p.bump_compound(kind, n); + } + } + expr_bp(p, r, op_bp + 1); + lhs = m.complete(p, if is_range { RANGE_EXPR } else { BIN_EXPR }); + } + BlockLike::NotBlock +} + +// test no_semi_after_block +// fn foo() { +// if true {} +// loop {} +// match () {} +// while true {} +// for _ in () {} +// {} +// {} +// } +fn is_block(kind: SyntaxKind) -> bool { + match kind { + IF_EXPR | WHILE_EXPR | FOR_EXPR | LOOP_EXPR | MATCH_EXPR | BLOCK_EXPR => true, + _ => false, + } +} + +const LHS_FIRST: TokenSet = + token_set_union![ + token_set![AMP, STAR, EXCL, DOTDOT, MINUS], + atom::ATOM_EXPR_FIRST, + ]; + +fn lhs(p: &mut Parser, r: Restrictions) -> Option { + let m; + let kind = match p.current() { + // test ref_expr + // fn foo() { + // let _ = &1; + // let _ = &mut &f(); + // } + AMP => { + m = p.start(); + p.bump(); + p.eat(MUT_KW); + REF_EXPR + } + // test unary_expr + // fn foo() { + // **&1; + // !!true; + // --1; + // } + STAR | EXCL | MINUS => { + m = p.start(); + p.bump(); + PREFIX_EXPR + } + DOTDOT => { + m = p.start(); + p.bump(); + expr_bp(p, r, 2); + return Some(m.complete(p, RANGE_EXPR)); + } + _ => { + let lhs = atom::atom_expr(p, r)?; + return Some(postfix_expr(p, r, lhs)); + } + }; + expr_bp(p, r, 255); + Some(m.complete(p, kind)) +} + +fn postfix_expr(p: &mut Parser, r: Restrictions, mut lhs: CompletedMarker) -> CompletedMarker { + let mut allow_calls = !r.prefer_stmt || !is_block(lhs.kind()); + loop { + lhs = match p.current() { + // test stmt_postfix_expr_ambiguity + // fn foo() { + // match () { + // _ => {} + // () => {} + // [] => {} + // } + // } + L_PAREN if allow_calls => call_expr(p, lhs), + L_BRACK if allow_calls => index_expr(p, lhs), + DOT if p.nth(1) == IDENT => if p.nth(2) == L_PAREN || p.nth(2) == COLONCOLON { + method_call_expr(p, lhs) + } else { + field_expr(p, lhs) + }, + DOT if p.nth(1) == INT_NUMBER => field_expr(p, lhs), + // test postfix_range + // fn foo() { let x = 1..; } + DOTDOT if !EXPR_FIRST.contains(p.nth(1)) => { + let m = lhs.precede(p); + p.bump(); + m.complete(p, RANGE_EXPR) + } + QUESTION => try_expr(p, lhs), + AS_KW => cast_expr(p, lhs), + _ => break, + }; + allow_calls = true + } + lhs +} + +// test call_expr +// fn foo() { +// let _ = f(); +// let _ = f()(1)(1, 2,); +// } +fn call_expr(p: &mut Parser, lhs: CompletedMarker) -> CompletedMarker { + assert!(p.at(L_PAREN)); + let m = lhs.precede(p); + arg_list(p); + m.complete(p, CALL_EXPR) +} + +// test index_expr +// fn foo() { +// x[1][2]; +// } +fn index_expr(p: &mut Parser, lhs: CompletedMarker) -> CompletedMarker { + assert!(p.at(L_BRACK)); + let m = lhs.precede(p); + p.bump(); + expr(p); + p.expect(R_BRACK); + m.complete(p, INDEX_EXPR) +} + +// test method_call_expr +// fn foo() { +// x.foo(); +// y.bar::(1, 2,); +// } +fn method_call_expr(p: &mut Parser, lhs: CompletedMarker) -> CompletedMarker { + assert!( + p.at(DOT) && p.nth(1) == IDENT + && (p.nth(2) == L_PAREN || p.nth(2) == COLONCOLON) + ); + let m = lhs.precede(p); + p.bump(); + name_ref(p); + type_args::type_arg_list(p, true); + arg_list(p); + m.complete(p, METHOD_CALL_EXPR) +} + +// test field_expr +// fn foo() { +// x.foo; +// x.0.bar; +// } +fn field_expr(p: &mut Parser, lhs: CompletedMarker) -> CompletedMarker { + assert!(p.at(DOT) && (p.nth(1) == IDENT || p.nth(1) == INT_NUMBER)); + let m = lhs.precede(p); + p.bump(); + if p.at(IDENT) { + name_ref(p) + } else { + p.bump() + } + m.complete(p, FIELD_EXPR) +} + +// test try_expr +// fn foo() { +// x?; +// } +fn try_expr(p: &mut Parser, lhs: CompletedMarker) -> CompletedMarker { + assert!(p.at(QUESTION)); + let m = lhs.precede(p); + p.bump(); + m.complete(p, TRY_EXPR) +} + +// test cast_expr +// fn foo() { +// 82 as i32; +// } +fn cast_expr(p: &mut Parser, lhs: CompletedMarker) -> CompletedMarker { + assert!(p.at(AS_KW)); + let m = lhs.precede(p); + p.bump(); + types::type_(p); + m.complete(p, CAST_EXPR) +} + +fn arg_list(p: &mut Parser) { + assert!(p.at(L_PAREN)); + let m = p.start(); + p.bump(); + while !p.at(R_PAREN) && !p.at(EOF) { + expr(p); + if !p.at(R_PAREN) && !p.expect(COMMA) { + break; + } + } + p.eat(R_PAREN); + m.complete(p, ARG_LIST); +} + +// test path_expr +// fn foo() { +// let _ = a; +// let _ = a::b; +// let _ = ::a::; +// let _ = format!(); +// } +fn path_expr(p: &mut Parser, r: Restrictions) -> CompletedMarker { + assert!(paths::is_path_start(p)); + let m = p.start(); + paths::expr_path(p); + match p.current() { + L_CURLY if !r.forbid_structs => { + struct_lit(p); + m.complete(p, STRUCT_LIT) + } + EXCL => { + items::macro_call_after_excl(p); + m.complete(p, MACRO_CALL) + } + _ => m.complete(p, PATH_EXPR) + } +} + +// test struct_lit +// fn foo() { +// S {}; +// S { x, y: 32, }; +// S { x, y: 32, ..Default::default() }; +// } +fn struct_lit(p: &mut Parser) { + assert!(p.at(L_CURLY)); + p.bump(); + while !p.at(EOF) && !p.at(R_CURLY) { + match p.current() { + IDENT => { + let m = p.start(); + name_ref(p); + if p.eat(COLON) { + expr(p); + } + m.complete(p, STRUCT_LIT_FIELD); + } + DOTDOT => { + p.bump(); + expr(p); + } + _ => p.err_and_bump("expected identifier"), + } + if !p.at(R_CURLY) { + p.expect(COMMA); + } + } + p.expect(R_CURLY); +} diff --git a/crates/libsyntax2/src/grammar/items/consts.rs b/crates/libsyntax2/src/grammar/items/consts.rs new file mode 100644 index 000000000..b11949b49 --- /dev/null +++ b/crates/libsyntax2/src/grammar/items/consts.rs @@ -0,0 +1,21 @@ +use super::*; + +pub(super) fn static_item(p: &mut Parser) { + const_or_static(p, STATIC_KW) +} + +pub(super) fn const_item(p: &mut Parser) { + const_or_static(p, CONST_KW) +} + +fn const_or_static(p: &mut Parser, kw: SyntaxKind) { + assert!(p.at(kw)); + p.bump(); + p.eat(MUT_KW); // TODO: validator to forbid const mut + name(p); + types::ascription(p); + if p.eat(EQ) { + expressions::expr(p); + } + p.expect(SEMI); +} diff --git a/crates/libsyntax2/src/grammar/items/mod.rs b/crates/libsyntax2/src/grammar/items/mod.rs new file mode 100644 index 000000000..3bf906f85 --- /dev/null +++ b/crates/libsyntax2/src/grammar/items/mod.rs @@ -0,0 +1,332 @@ +use super::*; + +mod consts; +mod structs; +mod traits; +mod use_item; + +// test mod_contents +// fn foo() {} +// macro_rules! foo {} +// foo::bar!(); +// super::baz! {} +// struct S; +pub(super) fn mod_contents(p: &mut Parser, stop_on_r_curly: bool) { + attributes::inner_attributes(p); + while !p.at(EOF) && !(stop_on_r_curly && p.at(R_CURLY)) { + item_or_macro(p, stop_on_r_curly) + } +} + +pub(super) fn item_or_macro(p: &mut Parser, stop_on_r_curly: bool) { + let m = p.start(); + match maybe_item(p) { + MaybeItem::Item(kind) => { + m.complete(p, kind); + } + MaybeItem::None => { + if paths::is_path_start(p) { + match macro_call(p) { + BlockLike::Block => (), + BlockLike::NotBlock => { + p.expect(SEMI); + } + } + m.complete(p, MACRO_CALL); + } else { + m.abandon(p); + if p.at(L_CURLY) { + error_block(p, "expected an item"); + } else if !p.at(EOF) && !(stop_on_r_curly && p.at(R_CURLY)) { + p.err_and_bump("expected an item"); + } else { + p.error("expected an item"); + } + } + } + MaybeItem::Modifiers => { + p.error("expected fn, trait or impl"); + m.complete(p, ERROR); + } + } +} + +pub(super) const ITEM_FIRST: TokenSet = + token_set![EXTERN_KW, MOD_KW, USE_KW, STRUCT_KW, ENUM_KW, FN_KW, PUB_KW, POUND]; + +pub(super) enum MaybeItem { + None, + Item(SyntaxKind), + Modifiers, +} + +pub(super) fn maybe_item(p: &mut Parser) -> MaybeItem { + attributes::outer_attributes(p); + visibility(p); + if let Some(kind) = items_without_modifiers(p) { + return MaybeItem::Item(kind); + } + + let mut has_mods = false; + // modifiers + has_mods |= p.eat(CONST_KW); + + // test unsafe_block_in_mod + // fn foo(){} unsafe { } fn bar(){} + if p.at(UNSAFE_KW) && p.nth(1) != L_CURLY { + p.eat(UNSAFE_KW); + has_mods = true; + } + if p.at(EXTERN_KW) { + has_mods = true; + abi(p); + } + if p.at(IDENT) && p.at_contextual_kw("auto") && p.nth(1) == TRAIT_KW { + p.bump_remap(AUTO_KW); + has_mods = true; + } + if p.at(IDENT) && p.at_contextual_kw("default") && p.nth(1) == IMPL_KW { + p.bump_remap(DEFAULT_KW); + has_mods = true; + } + + // items + let kind = match p.current() { + // test extern_fn + // extern fn foo() {} + + // test const_fn + // const fn foo() {} + + // test const_unsafe_fn + // const unsafe fn foo() {} + + // test unsafe_extern_fn + // unsafe extern "C" fn foo() {} + + // test unsafe_fn + // unsafe fn foo() {} + FN_KW => { + function(p); + FUNCTION + } + + // test unsafe_trait + // unsafe trait T {} + + // test auto_trait + // auto trait T {} + + // test unsafe_auto_trait + // unsafe auto trait T {} + TRAIT_KW => { + traits::trait_item(p); + TRAIT_ITEM + } + + // test unsafe_impl + // unsafe impl Foo {} + + // test default_impl + // default impl Foo {} + + // test unsafe_default_impl + // unsafe default impl Foo {} + IMPL_KW => { + traits::impl_item(p); + IMPL_ITEM + } + _ => return if has_mods { + MaybeItem::Modifiers + } else { + MaybeItem::None + } + }; + + MaybeItem::Item(kind) +} + +fn items_without_modifiers(p: &mut Parser) -> Option { + let la = p.nth(1); + let kind = match p.current() { + // test extern_crate + // extern crate foo; + EXTERN_KW if la == CRATE_KW => { + extern_crate_item(p); + EXTERN_CRATE_ITEM + } + TYPE_KW => { + type_item(p); + TYPE_ITEM + } + MOD_KW => { + mod_item(p); + MOD_ITEM + } + STRUCT_KW => { + structs::struct_item(p); + if p.at(SEMI) { + p.err_and_bump( + "expected item, found `;`\n\ + consider removing this semicolon" + ); + } + STRUCT_ITEM + } + ENUM_KW => { + structs::enum_item(p); + ENUM_ITEM + } + USE_KW => { + use_item::use_item(p); + USE_ITEM + } + CONST_KW if (la == IDENT || la == MUT_KW) => { + consts::const_item(p); + CONST_ITEM + } + STATIC_KW => { + consts::static_item(p); + STATIC_ITEM + } + // test extern_block + // extern {} + EXTERN_KW if la == L_CURLY || ((la == STRING || la == RAW_STRING) && p.nth(2) == L_CURLY) => { + abi(p); + extern_block(p); + EXTERN_BLOCK_EXPR + } + _ => return None, + }; + Some(kind) +} + +fn extern_crate_item(p: &mut Parser) { + assert!(p.at(EXTERN_KW)); + p.bump(); + assert!(p.at(CRATE_KW)); + p.bump(); + name(p); + alias(p); + p.expect(SEMI); +} + +fn extern_block(p: &mut Parser) { + assert!(p.at(L_CURLY)); + p.bump(); + p.expect(R_CURLY); +} + +fn function(p: &mut Parser) { + assert!(p.at(FN_KW)); + p.bump(); + + name(p); + // test function_type_params + // fn foo(){} + type_params::type_param_list(p); + + if p.at(L_PAREN) { + params::param_list(p); + } else { + p.error("expected function arguments"); + } + // test function_ret_type + // fn foo() {} + // fn bar() -> () {} + fn_ret_type(p); + + // test function_where_clause + // fn foo() where T: Copy {} + type_params::where_clause(p); + + // test fn_decl + // trait T { fn foo(); } + if !p.eat(SEMI) { + expressions::block(p); + } +} + +// test type_item +// type Foo = Bar; +fn type_item(p: &mut Parser) { + assert!(p.at(TYPE_KW)); + p.bump(); + + name(p); + + // test type_item_type_params + // type Result = (); + type_params::type_param_list(p); + + if p.at(COLON) { + type_params::bounds(p); + } + + // test type_item_where_clause + // type Foo where Foo: Copy = (); + type_params::where_clause(p); + + if p.eat(EQ) { + types::type_(p); + } + p.expect(SEMI); +} + +fn mod_item(p: &mut Parser) { + assert!(p.at(MOD_KW)); + p.bump(); + + name(p); + if !p.eat(SEMI) { + if p.expect(L_CURLY) { + mod_contents(p, true); + p.expect(R_CURLY); + } + } +} + +fn macro_call(p: &mut Parser) -> BlockLike { + assert!(paths::is_path_start(p)); + paths::use_path(p); + macro_call_after_excl(p) +} + +pub(super) fn macro_call_after_excl(p: &mut Parser) -> BlockLike { + p.expect(EXCL); + p.eat(IDENT); + let flavor = match p.current() { + L_CURLY => { + token_tree(p); + BlockLike::Block + } + L_PAREN | L_BRACK => { + token_tree(p); + BlockLike::NotBlock + } + _ => { + p.error("expected `{`, `[`, `(`"); + BlockLike::NotBlock + }, + }; + + flavor +} + +fn token_tree(p: &mut Parser) { + let closing_paren_kind = match p.current() { + L_CURLY => R_CURLY, + L_PAREN => R_PAREN, + L_BRACK => R_BRACK, + _ => unreachable!(), + }; + p.bump(); + while !p.at(EOF) && !p.at(closing_paren_kind) { + match p.current() { + L_CURLY | L_PAREN | L_BRACK => token_tree(p), + R_CURLY | R_PAREN | R_BRACK => p.err_and_bump("unmatched brace"), + _ => p.bump() + } + }; + p.expect(closing_paren_kind); +} diff --git a/crates/libsyntax2/src/grammar/items/structs.rs b/crates/libsyntax2/src/grammar/items/structs.rs new file mode 100644 index 000000000..67616eaad --- /dev/null +++ b/crates/libsyntax2/src/grammar/items/structs.rs @@ -0,0 +1,116 @@ +use super::*; + +pub(super) fn struct_item(p: &mut Parser) { + assert!(p.at(STRUCT_KW)); + p.bump(); + + name(p); + type_params::type_param_list(p); + match p.current() { + WHERE_KW => { + type_params::where_clause(p); + match p.current() { + SEMI => { + p.bump(); + return; + } + L_CURLY => named_fields(p), + _ => { + //TODO: special case `(` error message + p.error("expected `;` or `{`"); + return; + } + } + } + SEMI => { + p.bump(); + return; + } + L_CURLY => named_fields(p), + L_PAREN => { + pos_fields(p); + p.expect(SEMI); + } + _ => { + p.error("expected `;`, `{`, or `(`"); + return; + } + } +} + +pub(super) fn enum_item(p: &mut Parser) { + assert!(p.at(ENUM_KW)); + p.bump(); + name(p); + type_params::type_param_list(p); + type_params::where_clause(p); + if p.expect(L_CURLY) { + while !p.at(EOF) && !p.at(R_CURLY) { + let var = p.start(); + attributes::outer_attributes(p); + if p.at(IDENT) { + name(p); + match p.current() { + L_CURLY => named_fields(p), + L_PAREN => pos_fields(p), + EQ => { + p.bump(); + expressions::expr(p); + } + _ => (), + } + var.complete(p, ENUM_VARIANT); + } else { + var.abandon(p); + p.err_and_bump("expected enum variant"); + } + if !p.at(R_CURLY) { + p.expect(COMMA); + } + } + p.expect(R_CURLY); + } +} + +fn named_fields(p: &mut Parser) { + assert!(p.at(L_CURLY)); + p.bump(); + while !p.at(R_CURLY) && !p.at(EOF) { + named_field(p); + if !p.at(R_CURLY) { + p.expect(COMMA); + } + } + p.expect(R_CURLY); + + fn named_field(p: &mut Parser) { + let field = p.start(); + visibility(p); + if p.at(IDENT) { + name(p); + p.expect(COLON); + types::type_(p); + field.complete(p, NAMED_FIELD); + } else { + field.abandon(p); + p.err_and_bump("expected field declaration"); + } + } +} + +fn pos_fields(p: &mut Parser) { + if !p.expect(L_PAREN) { + return; + } + while !p.at(R_PAREN) && !p.at(EOF) { + let pos_field = p.start(); + visibility(p); + types::type_(p); + pos_field.complete(p, POS_FIELD); + + if !p.at(R_PAREN) { + p.expect(COMMA); + } + } + p.expect(R_PAREN); +} diff --git a/crates/libsyntax2/src/grammar/items/traits.rs b/crates/libsyntax2/src/grammar/items/traits.rs new file mode 100644 index 000000000..0b9fb2b0b --- /dev/null +++ b/crates/libsyntax2/src/grammar/items/traits.rs @@ -0,0 +1,87 @@ +use super::*; + +// test trait_item +// trait T: Hash + Clone where U: Copy {} +pub(super) fn trait_item(p: &mut Parser) { + assert!(p.at(TRAIT_KW)); + p.bump(); + name(p); + type_params::type_param_list(p); + if p.at(COLON) { + type_params::bounds(p); + } + type_params::where_clause(p); + p.expect(L_CURLY); + // test trait_item_items + // impl F { + // type A: Clone; + // const B: i32; + // fn foo() {} + // fn bar(&self); + // } + while !p.at(EOF) && !p.at(R_CURLY) { + item_or_macro(p, true); + } + p.expect(R_CURLY); +} + +// test impl_item +// impl Foo {} +pub(super) fn impl_item(p: &mut Parser) { + assert!(p.at(IMPL_KW)); + p.bump(); + if choose_type_params_over_qpath(p) { + type_params::type_param_list(p); + } + + // TODO: never type + // impl ! {} + + // test impl_item_neg + // impl !Send for X {} + p.eat(EXCL); + types::type_(p); + if p.eat(FOR_KW) { + types::type_(p); + } + type_params::where_clause(p); + p.expect(L_CURLY); + + // test impl_item_items + // impl F { + // type A = i32; + // const B: i32 = 92; + // fn foo() {} + // fn bar(&self) {} + // } + while !p.at(EOF) && !p.at(R_CURLY) { + item_or_macro(p, true); + } + p.expect(R_CURLY); +} + +fn choose_type_params_over_qpath(p: &Parser) -> bool { + // There's an ambiguity between generic parameters and qualified paths in impls. + // If we see `<` it may start both, so we have to inspect some following tokens. + // The following combinations can only start generics, + // but not qualified paths (with one exception): + // `<` `>` - empty generic parameters + // `<` `#` - generic parameters with attributes + // `<` (LIFETIME|IDENT) `>` - single generic parameter + // `<` (LIFETIME|IDENT) `,` - first generic parameter in a list + // `<` (LIFETIME|IDENT) `:` - generic parameter with bounds + // `<` (LIFETIME|IDENT) `=` - generic parameter with a default + // The only truly ambiguous case is + // `<` IDENT `>` `::` IDENT ... + // we disambiguate it in favor of generics (`impl ::absolute::Path { ... }`) + // because this is what almost always expected in practice, qualified paths in impls + // (`impl ::AssocTy { ... }`) aren't even allowed by type checker at the moment. + if !p.at(L_ANGLE) { + return false; + } + if p.nth(1) == POUND || p.nth(1) == R_ANGLE { + return true; + } + (p.nth(1) == LIFETIME || p.nth(1) == IDENT) + && (p.nth(2) == R_ANGLE || p.nth(2) == COMMA || p.nth(2) == COLON || p.nth(2) == EQ) +} diff --git a/crates/libsyntax2/src/grammar/items/use_item.rs b/crates/libsyntax2/src/grammar/items/use_item.rs new file mode 100644 index 000000000..a3f7f0da8 --- /dev/null +++ b/crates/libsyntax2/src/grammar/items/use_item.rs @@ -0,0 +1,66 @@ +use super::*; + +pub(super) fn use_item(p: &mut Parser) { + assert!(p.at(USE_KW)); + p.bump(); + use_tree(p); + p.expect(SEMI); +} + +fn use_tree(p: &mut Parser) { + let la = p.nth(1); + let m = p.start(); + match (p.current(), la) { + (STAR, _) => p.bump(), + (COLONCOLON, STAR) => { + p.bump(); + p.bump(); + } + (L_CURLY, _) | (COLONCOLON, L_CURLY) => { + if p.at(COLONCOLON) { + p.bump(); + } + nested_trees(p); + } + _ if paths::is_path_start(p) => { + paths::use_path(p); + match p.current() { + AS_KW => { + alias(p); + } + COLONCOLON => { + p.bump(); + match p.current() { + STAR => { + p.bump(); + } + L_CURLY => nested_trees(p), + _ => { + // is this unreachable? + p.error("expected `{` or `*`"); + } + } + } + _ => (), + } + } + _ => { + m.abandon(p); + p.err_and_bump("expected one of `*`, `::`, `{`, `self`, `super`, `indent`"); + return; + } + } + m.complete(p, USE_TREE); +} + +fn nested_trees(p: &mut Parser) { + assert!(p.at(L_CURLY)); + p.bump(); + while !p.at(EOF) && !p.at(R_CURLY) { + use_tree(p); + if !p.at(R_CURLY) { + p.expect(COMMA); + } + } + p.expect(R_CURLY); +} diff --git a/crates/libsyntax2/src/grammar/mod.rs b/crates/libsyntax2/src/grammar/mod.rs new file mode 100644 index 000000000..e1329044d --- /dev/null +++ b/crates/libsyntax2/src/grammar/mod.rs @@ -0,0 +1,161 @@ +//! This is the actual "grammar" of the Rust language. +//! +//! Each function in this module and its children corresponds +//! to a production of the format grammar. Submodules roughly +//! correspond to different *areas* of the grammar. By convention, +//! each submodule starts with `use super::*` import and exports +//! "public" productions via `pub(super)`. +//! +//! See docs for `Parser` to learn about API, available to the grammar, +//! and see docs for `Event` to learn how this actually manages to +//! produce parse trees. +//! +//! Code in this module also contains inline tests, which start with +//! `// test name-of-the-test` comment and look like this: +//! +//! ``` +//! // test function_with_zero_parameters +//! // fn foo() {} +//! ``` +//! +//! After adding a new inline-test, run `cargo collect-tests` to extract +//! it as a standalone text-fixture into `tests/data/parser/inline`, and +//! run `cargo test` once to create the "gold" value. +mod attributes; +mod expressions; +mod items; +mod params; +mod paths; +mod patterns; +mod type_args; +mod type_params; +mod types; + +use { + parser_api::{CompletedMarker, Parser, TokenSet}, + SyntaxKind::{self, *}, +}; + +pub(crate) fn file(p: &mut Parser) { + let file = p.start(); + p.eat(SHEBANG); + items::mod_contents(p, false); + file.complete(p, FILE); +} + + +#[derive(Clone, Copy, PartialEq, Eq)] +enum BlockLike { + Block, + NotBlock, +} + +impl BlockLike { + fn is_block(self) -> bool { self == BlockLike::Block } +} + +fn visibility(p: &mut Parser) { + match p.current() { + PUB_KW => { + let m = p.start(); + p.bump(); + if p.at(L_PAREN) { + match p.nth(1) { + // test crate_visibility + // pub(crate) struct S; + // pub(self) struct S; + // pub(self) struct S; + // pub(self) struct S; + CRATE_KW | SELF_KW | SUPER_KW => { + p.bump(); + p.bump(); + p.expect(R_PAREN); + } + IN_KW => { + p.bump(); + p.bump(); + paths::use_path(p); + p.expect(R_PAREN); + } + _ => (), + } + } + m.complete(p, VISIBILITY); + } + // test crate_keyword_vis + // crate fn main() { } + CRATE_KW => { + let m = p.start(); + p.bump(); + m.complete(p, VISIBILITY); + } + _ => (), + } +} +fn alias(p: &mut Parser) -> bool { + if p.at(AS_KW) { + let alias = p.start(); + p.bump(); + name(p); + alias.complete(p, ALIAS); + } + true //FIXME: return false if three are errors +} + +fn abi(p: &mut Parser) { + assert!(p.at(EXTERN_KW)); + let abi = p.start(); + p.bump(); + match p.current() { + STRING | RAW_STRING => p.bump(), + _ => (), + } + abi.complete(p, ABI); +} + +fn fn_ret_type(p: &mut Parser) -> bool { + if p.at(THIN_ARROW) { + p.bump(); + types::type_(p); + true + } else { + false + } +} + +fn name(p: &mut Parser) { + if p.at(IDENT) { + let m = p.start(); + p.bump(); + m.complete(p, NAME); + } else { + p.error("expected a name"); + } +} + +fn name_ref(p: &mut Parser) { + if p.at(IDENT) { + let m = p.start(); + p.bump(); + m.complete(p, NAME_REF); + } else { + p.error("expected identifier"); + } +} + +fn error_block(p: &mut Parser, message: &str) { + assert!(p.at(L_CURLY)); + let err = p.start(); + p.error(message); + p.bump(); + let mut level: u32 = 1; + while level > 0 && !p.at(EOF) { + match p.current() { + L_CURLY => level += 1, + R_CURLY => level -= 1, + _ => (), + } + p.bump(); + } + err.complete(p, ERROR); +} diff --git a/crates/libsyntax2/src/grammar/params.rs b/crates/libsyntax2/src/grammar/params.rs new file mode 100644 index 000000000..32e905cb2 --- /dev/null +++ b/crates/libsyntax2/src/grammar/params.rs @@ -0,0 +1,116 @@ +use super::*; + +// test param_list +// fn a() {} +// fn b(x: i32) {} +// fn c(x: i32, ) {} +// fn d(x: i32, y: ()) {} +pub(super) fn param_list(p: &mut Parser) { + list_(p, Flavor::Normal) +} + +// test param_list_opt_patterns +// fn foo)>(){} +pub(super) fn param_list_opt_patterns(p: &mut Parser) { + list_(p, Flavor::OptionalPattern) +} + +pub(super) fn param_list_opt_types(p: &mut Parser) { + list_(p, Flavor::OptionalType) +} + +#[derive(Clone, Copy, Eq, PartialEq)] +enum Flavor { + OptionalType, + OptionalPattern, + Normal, +} + +impl Flavor { + fn type_required(self) -> bool { + match self { + Flavor::OptionalType => false, + _ => true, + } + } +} + +fn list_(p: &mut Parser, flavor: Flavor) { + let (bra, ket) = if flavor.type_required() { + (L_PAREN, R_PAREN) + } else { + (PIPE, PIPE) + }; + assert!(p.at(bra)); + let m = p.start(); + p.bump(); + if flavor.type_required() { + self_param(p); + } + while !p.at(EOF) && !p.at(ket) { + value_parameter(p, flavor); + if !p.at(ket) { + p.expect(COMMA); + } + } + p.expect(ket); + m.complete(p, PARAM_LIST); +} + +fn value_parameter(p: &mut Parser, flavor: Flavor) { + let m = p.start(); + match flavor { + Flavor::OptionalType | Flavor::Normal => { + patterns::pattern(p); + if p.at(COLON) || flavor.type_required() { + types::ascription(p) + } + }, + // test value_parameters_no_patterns + // type F = Box; + Flavor::OptionalPattern => { + let la0 = p.current(); + let la1 = p.nth(1); + let la2 = p.nth(2); + let la3 = p.nth(3); + if la0 == IDENT && la1 == COLON + || la0 == AMP && la1 == IDENT && la2 == COLON + || la0 == AMP && la1 == MUT_KW && la2 == IDENT && la3 == COLON { + patterns::pattern(p); + types::ascription(p); + } else { + types::type_(p); + } + }, + } + m.complete(p, PARAM); +} + +// test self_param +// impl S { +// fn a(self) {} +// fn b(&self,) {} +// fn c(&'a self,) {} +// fn d(&'a mut self, x: i32) {} +// } +fn self_param(p: &mut Parser) { + let la1 = p.nth(1); + let la2 = p.nth(2); + let la3 = p.nth(3); + let n_toks = match (p.current(), la1, la2, la3) { + (SELF_KW, _, _, _) => 1, + (AMP, SELF_KW, _, _) => 2, + (AMP, MUT_KW, SELF_KW, _) => 3, + (AMP, LIFETIME, SELF_KW, _) => 3, + (AMP, LIFETIME, MUT_KW, SELF_KW) => 4, + _ => return, + }; + let m = p.start(); + for _ in 0..n_toks { + p.bump(); + } + m.complete(p, SELF_PARAM); + if !p.at(R_PAREN) { + p.expect(COMMA); + } +} diff --git a/crates/libsyntax2/src/grammar/paths.rs b/crates/libsyntax2/src/grammar/paths.rs new file mode 100644 index 000000000..c277e2a6b --- /dev/null +++ b/crates/libsyntax2/src/grammar/paths.rs @@ -0,0 +1,86 @@ +use super::*; + +pub(super) fn is_path_start(p: &Parser) -> bool { + match p.current() { + IDENT | SELF_KW | SUPER_KW | COLONCOLON => true, + _ => false, + } +} + +pub(super) fn use_path(p: &mut Parser) { + path(p, Mode::Use) +} + +pub(super) fn type_path(p: &mut Parser) { + path(p, Mode::Type) +} + +pub(super) fn expr_path(p: &mut Parser) { + path(p, Mode::Expr) +} + +#[derive(Clone, Copy, Eq, PartialEq)] +enum Mode { + Use, + Type, + Expr, +} + +fn path(p: &mut Parser, mode: Mode) { + if !is_path_start(p) { + return; + } + let path = p.start(); + path_segment(p, mode, true); + let mut qual = path.complete(p, PATH); + loop { + let use_tree = match p.nth(1) { + STAR | L_CURLY => true, + _ => false, + }; + if p.at(COLONCOLON) && !use_tree { + let path = qual.precede(p); + p.bump(); + path_segment(p, mode, false); + let path = path.complete(p, PATH); + qual = path; + } else { + break; + } + } +} + +fn path_segment(p: &mut Parser, mode: Mode, first: bool) { + let segment = p.start(); + if first { + p.eat(COLONCOLON); + } + match p.current() { + IDENT => { + name_ref(p); + path_generic_args(p, mode); + } + SELF_KW | SUPER_KW => p.bump(), + _ => { + p.error("expected identifier"); + } + }; + segment.complete(p, PATH_SEGMENT); +} + +fn path_generic_args(p: &mut Parser, mode: Mode) { + match mode { + Mode::Use => return, + Mode::Type => { + // test path_fn_trait_args + // type F = Box ()>; + if p.at(L_PAREN) { + params::param_list_opt_patterns(p); + fn_ret_type(p); + } else { + type_args::type_arg_list(p, false) + } + }, + Mode::Expr => type_args::type_arg_list(p, true), + } +} diff --git a/crates/libsyntax2/src/grammar/patterns.rs b/crates/libsyntax2/src/grammar/patterns.rs new file mode 100644 index 000000000..436f3b26d --- /dev/null +++ b/crates/libsyntax2/src/grammar/patterns.rs @@ -0,0 +1,204 @@ +use super::*; + +pub(super) fn pattern(p: &mut Parser) { + if let Some(lhs) = atom_pat(p) { + // test range_pat + // fn main() { + // match 92 { 0 ... 100 => () } + // } + if p.at(DOTDOTDOT) { + let m = lhs.precede(p); + p.bump(); + atom_pat(p); + m.complete(p, RANGE_PAT); + } + } +} + +fn atom_pat(p: &mut Parser) -> Option { + let la0 = p.nth(0); + let la1 = p.nth(1); + if la0 == REF_KW || la0 == MUT_KW + || (la0 == IDENT && !(la1 == COLONCOLON || la1 == L_PAREN || la1 == L_CURLY)) { + return Some(bind_pat(p, true)); + } + if paths::is_path_start(p) { + return Some(path_pat(p)); + } + + // test literal_pattern + // fn main() { + // match () { + // 92 => (), + // 'c' => (), + // "hello" => (), + // } + // } + match expressions::literal(p) { + Some(m) => return Some(m), + None => (), + } + + let m = match la0 { + UNDERSCORE => placeholder_pat(p), + AMP => ref_pat(p), + L_PAREN => tuple_pat(p), + L_BRACK => slice_pat(p), + _ => { + p.err_and_bump("expected pattern"); + return None; + } + }; + Some(m) +} + +// test path_part +// fn foo() { +// let foo::Bar = (); +// let ::Bar = (); +// let Bar { .. } = (); +// let Bar(..) = (); +// } +fn path_pat(p: &mut Parser) -> CompletedMarker { + let m = p.start(); + paths::expr_path(p); + let kind = match p.current() { + L_PAREN => { + tuple_pat_fields(p); + TUPLE_STRUCT_PAT + } + L_CURLY => { + struct_pat_fields(p); + STRUCT_PAT + } + _ => PATH_PAT + }; + m.complete(p, kind) +} + +// test tuple_pat_fields +// fn foo() { +// let S() = (); +// let S(_) = (); +// let S(_,) = (); +// let S(_, .. , x) = (); +// } +fn tuple_pat_fields(p: &mut Parser) { + assert!(p.at(L_PAREN)); + p.bump(); + while !p.at(EOF) && !p.at(R_PAREN) { + match p.current() { + DOTDOT => p.bump(), + _ => pattern(p), + } + if !p.at(R_PAREN) { + p.expect(COMMA); + } + } + p.expect(R_PAREN); +} + +// test struct_pat_fields +// fn foo() { +// let S {} = (); +// let S { f, ref mut g } = (); +// let S { h: _, ..} = (); +// let S { h: _, } = (); +// } +fn struct_pat_fields(p: &mut Parser) { + assert!(p.at(L_CURLY)); + p.bump(); + while !p.at(EOF) && !p.at(R_CURLY) { + match p.current() { + DOTDOT => p.bump(), + IDENT if p.nth(1) == COLON => { + p.bump(); + p.bump(); + pattern(p); + } + _ => { + bind_pat(p, false); + } + } + if !p.at(R_CURLY) { + p.expect(COMMA); + } + } + p.expect(R_CURLY); +} + +// test placeholder_pat +// fn main() { let _ = (); } +fn placeholder_pat(p: &mut Parser) -> CompletedMarker { + assert!(p.at(UNDERSCORE)); + let m = p.start(); + p.bump(); + m.complete(p, PLACEHOLDER_PAT) +} + +// test ref_pat +// fn main() { +// let &a = (); +// let &mut b = (); +// } +fn ref_pat(p: &mut Parser) -> CompletedMarker { + assert!(p.at(AMP)); + let m = p.start(); + p.bump(); + p.eat(MUT_KW); + pattern(p); + m.complete(p, REF_PAT) +} + +// test tuple_pat +// fn main() { +// let (a, b, ..) = (); +// } +fn tuple_pat(p: &mut Parser) -> CompletedMarker { + assert!(p.at(L_PAREN)); + let m = p.start(); + tuple_pat_fields(p); + m.complete(p, TUPLE_PAT) +} + +// test slice_pat +// fn main() { +// let [a, b, ..] = []; +// } +fn slice_pat(p: &mut Parser) -> CompletedMarker { + assert!(p.at(L_BRACK)); + let m = p.start(); + p.bump(); + while !p.at(EOF) && !p.at(R_BRACK) { + match p.current() { + DOTDOT => p.bump(), + _ => pattern(p), + } + if !p.at(R_BRACK) { + p.expect(COMMA); + } + } + p.expect(R_BRACK); + + m.complete(p, SLICE_PAT) +} + +// test bind_pat +// fn main() { +// let a = (); +// let mut b = (); +// let ref c = (); +// let ref mut d = (); +// let e @ _ = (); +// let ref mut f @ g @ _ = (); +// } +fn bind_pat(p: &mut Parser, with_at: bool) -> CompletedMarker { + let m = p.start(); + p.eat(REF_KW); + p.eat(MUT_KW); + name(p); + if with_at && p.eat(AT) { + pattern(p); + } + m.complete(p, BIND_PAT) +} diff --git a/crates/libsyntax2/src/grammar/type_args.rs b/crates/libsyntax2/src/grammar/type_args.rs new file mode 100644 index 000000000..5b960f10b --- /dev/null +++ b/crates/libsyntax2/src/grammar/type_args.rs @@ -0,0 +1,48 @@ +use super::*; + +pub(super) fn type_arg_list(p: &mut Parser, colon_colon_required: bool) { + let m; + match (colon_colon_required, p.nth(0), p.nth(1)) { + (_, COLONCOLON, L_ANGLE) => { + m = p.start(); + p.bump(); + p.bump(); + } + (false, L_ANGLE, _) => { + m = p.start(); + p.bump(); + } + _ => return, + }; + + while !p.at(EOF) && !p.at(R_ANGLE) { + type_arg(p); + if !p.at(R_ANGLE) && !p.expect(COMMA) { + break; + } + } + p.expect(R_ANGLE); + m.complete(p, TYPE_ARG_LIST); +} + +// test type_arg +// type A = B<'static, i32, Item=u64> +fn type_arg(p: &mut Parser) { + let m = p.start(); + match p.current() { + LIFETIME => { + p.bump(); + m.complete(p, LIFETIME_ARG); + } + IDENT if p.nth(1) == EQ => { + name_ref(p); + p.bump(); + types::type_(p); + m.complete(p, ASSOC_TYPE_ARG); + } + _ => { + types::type_(p); + m.complete(p, TYPE_ARG); + } + } +} diff --git a/crates/libsyntax2/src/grammar/type_params.rs b/crates/libsyntax2/src/grammar/type_params.rs new file mode 100644 index 000000000..0a3e8fd07 --- /dev/null +++ b/crates/libsyntax2/src/grammar/type_params.rs @@ -0,0 +1,127 @@ +use super::*; + +pub(super) fn type_param_list(p: &mut Parser) { + if !p.at(L_ANGLE) { + return; + } + let m = p.start(); + p.bump(); + + while !p.at(EOF) && !p.at(R_ANGLE) { + match p.current() { + LIFETIME => lifetime_param(p), + IDENT => type_param(p), + _ => p.err_and_bump("expected type parameter"), + } + if !p.at(R_ANGLE) && !p.expect(COMMA) { + break; + } + } + p.expect(R_ANGLE); + m.complete(p, TYPE_PARAM_LIST); + + fn lifetime_param(p: &mut Parser) { + assert!(p.at(LIFETIME)); + let m = p.start(); + p.bump(); + if p.at(COLON) { + lifetime_bounds(p); + } + m.complete(p, LIFETIME_PARAM); + } + + fn type_param(p: &mut Parser) { + assert!(p.at(IDENT)); + let m = p.start(); + name(p); + if p.at(COLON) { + bounds(p); + } + // test type_param_default + // struct S; + if p.at(EQ) { + p.bump(); + types::type_(p) + } + m.complete(p, TYPE_PARAM); + } +} + +// test type_param_bounds +// struct S; +pub(super) fn bounds(p: &mut Parser) { + assert!(p.at(COLON)); + p.bump(); + bounds_without_colon(p); +} + +fn lifetime_bounds(p: &mut Parser) { + assert!(p.at(COLON)); + p.bump(); + while p.at(LIFETIME) { + p.bump(); + if !p.eat(PLUS) { + break; + } + } +} + +pub(super) fn bounds_without_colon(p: &mut Parser) { + loop { + let has_paren = p.eat(L_PAREN); + p.eat(QUESTION); + if p.at(FOR_KW) { + //TODO + } + if p.at(LIFETIME) { + p.bump(); + } else if paths::is_path_start(p) { + paths::type_path(p); + } else { + break; + } + if has_paren { + p.expect(R_PAREN); + } + if !p.eat(PLUS) { + break; + } + } +} + +// test where_clause +// fn foo() +// where +// 'a: 'b + 'c, +// T: Clone + Copy + 'static, +// Iterator::Item: 'a, +// {} +pub(super) fn where_clause(p: &mut Parser) { + if !p.at(WHERE_KW) { + return; + } + let m = p.start(); + p.bump(); + loop { + if !(paths::is_path_start(p) || p.current() == LIFETIME) { + break + } + where_predicate(p); + if p.current() != L_CURLY && p.current() != SEMI { + p.expect(COMMA); + } + } + m.complete(p, WHERE_CLAUSE); +} + +fn where_predicate(p: &mut Parser) { + let m = p.start(); + if p.at(LIFETIME) { + p.eat(LIFETIME); + lifetime_bounds(p) + } else { + types::path_type(p); + bounds(p); + } + m.complete(p, WHERE_PRED); +} diff --git a/crates/libsyntax2/src/grammar/types.rs b/crates/libsyntax2/src/grammar/types.rs new file mode 100644 index 000000000..0d8c6bfba --- /dev/null +++ b/crates/libsyntax2/src/grammar/types.rs @@ -0,0 +1,212 @@ +use super::*; + +pub(super) fn type_(p: &mut Parser) { + match p.current() { + L_PAREN => paren_or_tuple_type(p), + EXCL => never_type(p), + STAR => pointer_type(p), + L_BRACK => array_or_slice_type(p), + AMP => reference_type(p), + UNDERSCORE => placeholder_type(p), + FN_KW | UNSAFE_KW | EXTERN_KW => fn_pointer_type(p), + FOR_KW => for_type(p), + IMPL_KW => impl_trait_type(p), + _ if paths::is_path_start(p) => path_type(p), + _ => { + p.error("expected type"); + } + } +} + +pub(super) fn ascription(p: &mut Parser) { + p.expect(COLON); + type_(p) +} + +fn type_no_plus(p: &mut Parser) { + type_(p); +} + +fn paren_or_tuple_type(p: &mut Parser) { + assert!(p.at(L_PAREN)); + let m = p.start(); + p.bump(); + let mut n_types: u32 = 0; + let mut trailing_comma: bool = false; + while !p.at(EOF) && !p.at(R_PAREN) { + n_types += 1; + type_(p); + if p.eat(COMMA) { + trailing_comma = true; + } else { + trailing_comma = false; + break; + } + } + p.expect(R_PAREN); + + let kind = if n_types == 1 && !trailing_comma { + // test paren_type + // type T = (i32); + PAREN_TYPE + } else { + // test unit_type + // type T = (); + + // test singleton_tuple_type + // type T = (i32,); + TUPLE_TYPE + }; + m.complete(p, kind); +} + +// test never_type +// type Never = !; +fn never_type(p: &mut Parser) { + assert!(p.at(EXCL)); + let m = p.start(); + p.bump(); + m.complete(p, NEVER_TYPE); +} + +fn pointer_type(p: &mut Parser) { + assert!(p.at(STAR)); + let m = p.start(); + p.bump(); + + match p.current() { + // test pointer_type_mut + // type M = *mut (); + // type C = *mut (); + MUT_KW | CONST_KW => p.bump(), + _ => { + // test pointer_type_no_mutability + // type T = *(); + p.error( + "expected mut or const in raw pointer type \ + (use `*mut T` or `*const T` as appropriate)", + ); + } + }; + + type_no_plus(p); + m.complete(p, POINTER_TYPE); +} + +fn array_or_slice_type(p: &mut Parser) { + assert!(p.at(L_BRACK)); + let m = p.start(); + p.bump(); + + type_(p); + let kind = match p.current() { + // test slice_type + // type T = [()]; + R_BRACK => { + p.bump(); + SLICE_TYPE + } + + // test array_type + // type T = [(); 92]; + SEMI => { + p.bump(); + expressions::expr(p); + p.expect(R_BRACK); + ARRAY_TYPE + } + // test array_type_missing_semi + // type T = [() 92]; + _ => { + p.error("expected `;` or `]`"); + SLICE_TYPE + } + }; + m.complete(p, kind); +} + +// test reference_type; +// type A = &(); +// type B = &'static (); +// type C = &mut (); +fn reference_type(p: &mut Parser) { + assert!(p.at(AMP)); + let m = p.start(); + p.bump(); + p.eat(LIFETIME); + p.eat(MUT_KW); + type_no_plus(p); + m.complete(p, REFERENCE_TYPE); +} + +// test placeholder_type +// type Placeholder = _; +fn placeholder_type(p: &mut Parser) { + assert!(p.at(UNDERSCORE)); + let m = p.start(); + p.bump(); + m.complete(p, PLACEHOLDER_TYPE); +} + +// test fn_pointer_type +// type A = fn(); +// type B = unsafe fn(); +// type C = unsafe extern "C" fn(); +fn fn_pointer_type(p: &mut Parser) { + let m = p.start(); + p.eat(UNSAFE_KW); + if p.at(EXTERN_KW) { + abi(p); + } + // test fn_pointer_type_missing_fn + // type F = unsafe (); + if !p.eat(FN_KW) { + m.abandon(p); + p.error("expected `fn`"); + return; + } + + params::param_list_opt_patterns(p); + // test fn_pointer_type_with_ret + // type F = fn() -> (); + fn_ret_type(p); + m.complete(p, FN_POINTER_TYPE); +} + +// test for_type +// type A = for<'a> fn() -> (); +fn for_type(p: &mut Parser) { + assert!(p.at(FOR_KW)); + let m = p.start(); + p.bump(); + type_params::type_param_list(p); + type_(p); + m.complete(p, FOR_TYPE); +} + +// test impl_trait_type +// type A = impl Iterator> + 'a; +fn impl_trait_type(p: &mut Parser) { + assert!(p.at(IMPL_KW)); + let m = p.start(); + p.bump(); + type_params::bounds_without_colon(p); + m.complete(p, IMPL_TRAIT_TYPE); +} + +// test path_type +// type A = Foo; +// type B = ::Foo; +// type C = self::Foo; +// type D = super::Foo; +pub(super) fn path_type(p: &mut Parser) { + assert!(paths::is_path_start(p)); + let m = p.start(); + paths::type_path(p); + // test path_type_with_bounds + // fn foo() -> Box {} + if p.eat(PLUS) { + type_params::bounds_without_colon(p); + } + m.complete(p, PATH_TYPE); +} -- cgit v1.2.3