1 files changed, 196 insertions, 0 deletions

diff --git a/src/parser/grammar/items/mod.rs b/src/parser/grammar/items/mod.rs
new file mode 100644
index 000000000..3612802e1
--- /dev/null
+++ b/src/parser/grammar/items/mod.rs
@@ -0,0 +1,196 @@
+use super::*;
+
+mod structs;
+mod use_item;
+mod consts;
+mod traits;
+
+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(p);
+    }
+}
+
+pub(super) const ITEM_FIRST: TokenSet = token_set![
+    EXTERN_KW, MOD_KW, USE_KW, STRUCT_KW, ENUM_KW, FN_KW, PUB_KW, POUND
+];
+
+fn item(p: &mut Parser) {
+    let item = p.start();
+    attributes::outer_attributes(p);
+    visibility(p);
+    let la = p.nth(1);
+    let item_kind = match p.current() {
+        USE_KW => {
+            use_item::use_item(p);
+            USE_ITEM
+        }
+        // test extern_crate
+        // extern crate foo;
+        EXTERN_KW if la == CRATE_KW => {
+            extern_crate_item(p);
+            EXTERN_CRATE_ITEM
+        }
+        EXTERN_KW => {
+            abi(p);
+            match p.current() {
+                // test extern_fn
+                // extern fn foo() {}
+                FN_KW => {
+                    fn_item(p);
+                    FN_ITEM
+                }
+                // test extern_block
+                // extern {}
+                L_CURLY => {
+                    extern_block(p);
+                    EXTERN_BLOCK
+                }
+                // test extern_struct
+                // extern struct Foo;
+                _ => {
+                    item.abandon(p);
+                    p.error().message("expected `fn` or `{`").emit();
+                    return;
+                }
+            }
+        }
+        STATIC_KW => {
+            consts::static_item(p);
+            STATIC_ITEM
+        }
+        CONST_KW => match p.nth(1) {
+            // test const_fn
+            // const fn foo() {}
+            FN_KW => {
+                p.bump();
+                fn_item(p);
+                FN_ITEM
+            }
+            // test const_unsafe_fn
+            // const unsafe fn foo() {}
+            UNSAFE_KW if p.nth(2) == FN_KW => {
+                p.bump();
+                p.bump();
+                fn_item(p);
+                FN_ITEM
+            }
+            _ => {
+                consts::const_item(p);
+                CONST_ITEM
+            }
+        },
+        // TODO: auto trait
+        // test unsafe_trait
+        // unsafe trait T {}
+        UNSAFE_KW if la == TRAIT_KW => {
+            p.bump();
+            traits::trait_item(p);
+            TRAIT_ITEM
+        }
+        // TODO: default impl
+        // test unsafe_impl
+        // unsafe impl Foo {}
+        UNSAFE_KW if la == IMPL_KW => {
+            p.bump();
+            traits::impl_item(p);
+            IMPL_ITEM
+        }
+        MOD_KW => {
+            mod_item(p);
+            MOD_ITEM
+        }
+        STRUCT_KW => {
+            structs::struct_item(p);
+            STRUCT_ITEM
+        }
+        ENUM_KW => {
+            structs::enum_item(p);
+            ENUM_ITEM
+        }
+        FN_KW => {
+            fn_item(p);
+            FN_ITEM
+        }
+        L_CURLY => {
+            item.abandon(p);
+            error_block(p, "expected item");
+            return;
+        }
+        err_token => {
+            item.abandon(p);
+            let message = if err_token == SEMI {
+                //TODO: if the item is incomplete, this message is misleading
+                "expected item, found `;`\n\
+                 consider removing this semicolon"
+            } else {
+                "expected item"
+            };
+            p.err_and_bump(message);
+            return;
+        }
+    };
+    item.complete(p, item_kind);
+}
+
+fn extern_crate_item(p: &mut Parser) {
+    assert!(p.at(EXTERN_KW));
+    p.bump();
+    assert!(p.at(CRATE_KW));
+    p.bump();
+
+    p.expect(IDENT) && alias(p) && p.expect(SEMI);
+}
+
+fn extern_block(p: &mut Parser) {
+    assert!(p.at(L_CURLY));
+    p.bump();
+    p.expect(R_CURLY);
+}
+
+fn mod_item(p: &mut Parser) {
+    assert!(p.at(MOD_KW));
+    p.bump();
+
+    if p.expect(IDENT) && !p.eat(SEMI) {
+        if p.expect(L_CURLY) {
+            mod_contents(p, true);
+            p.expect(R_CURLY);
+        }
+    }
+}
+
+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_item(p: &mut Parser) {
+    assert!(p.at(FN_KW));
+    p.bump();
+
+    p.expect(IDENT);
+    if p.at(L_PAREN) {
+        fn_value_parameters(p);
+    } else {
+        p.error().message("expected function arguments").emit();
+    }
+
+    if p.at(L_CURLY) {
+        p.expect(L_CURLY);
+        p.expect(R_CURLY);
+    }
+
+    fn fn_value_parameters(p: &mut Parser) {
+        assert!(p.at(L_PAREN));
+        p.bump();
+        p.expect(R_PAREN);
+    }
+}