8 files changed, 100 insertions, 30 deletions

diff --git a/crates/ra_hir_def/src/body/lower.rs b/crates/ra_hir_def/src/body/lower.rs
index 28c570c76..8d4b8b0f0 100644
--- a/crates/ra_hir_def/src/body/lower.rs
+++ b/crates/ra_hir_def/src/body/lower.rs
@@ -672,8 +672,7 @@ impl ExprCollector<'_> {
             }
 
             // FIXME: implement
-            ast::Pat::BoxPat(_) => Pat::Missing,
-            ast::Pat::RangePat(_) => Pat::Missing,
+            ast::Pat::BoxPat(_) | ast::Pat::RangePat(_) | ast::Pat::MacroPat(_) => Pat::Missing,
         };
         let ptr = AstPtr::new(&pat);
         self.alloc_pat(pattern, Either::Left(ptr))
diff --git a/crates/ra_hir_ty/src/tests/macros.rs b/crates/ra_hir_ty/src/tests/macros.rs
index eb97288f1..ff4599b71 100644
--- a/crates/ra_hir_ty/src/tests/macros.rs
+++ b/crates/ra_hir_ty/src/tests/macros.rs
@@ -1,8 +1,10 @@
-use super::{infer, type_at, type_at_pos};
-use crate::test_db::TestDB;
 use insta::assert_snapshot;
 use ra_db::fixture::WithFixture;
 
+use super::{infer, type_at, type_at_pos};
+
+use crate::test_db::TestDB;
+
 #[test]
 fn cfg_impl_def() {
     let (db, pos) = TestDB::with_position(
@@ -658,3 +660,28 @@ fn test() {
     );
     assert_eq!("S", type_at_pos(&db, pos));
 }
+
+#[test]
+fn macro_in_arm() {
+    assert_snapshot!(
+        infer(r#"
+macro_rules! unit {
+    () => { () };
+}
+
+fn main() {
+    let x = match () {
+        unit!() => 92u32,
+    };
+}
+"#),
+        @r###"
+    [52; 111) '{     ...  }; }': ()
+    [62; 63) 'x': u32
+    [66; 108) 'match ...     }': u32
+    [72; 74) '()': ()
+    [85; 92) 'unit!()': ()
+    [96; 101) '92u32': u32
+    "###
+    );
+}
diff --git a/crates/ra_parser/src/grammar/expressions.rs b/crates/ra_parser/src/grammar/expressions.rs
index 0c170ac5e..c486c0211 100644
--- a/crates/ra_parser/src/grammar/expressions.rs
+++ b/crates/ra_parser/src/grammar/expressions.rs
@@ -79,8 +79,6 @@ fn is_expr_stmt_attr_allowed(kind: SyntaxKind) -> bool {
 }
 
 pub(super) fn stmt(p: &mut Parser, with_semi: StmtWithSemi) {
-    // test block_items
-    // fn a() { fn b() {} }
     let m = p.start();
     // test attr_on_expr_stmt
     // fn foo() {
@@ -97,6 +95,8 @@ pub(super) fn stmt(p: &mut Parser, with_semi: StmtWithSemi) {
         return;
     }
 
+    // test block_items
+    // fn a() { fn b() {} }
     let m = match items::maybe_item(p, m, items::ItemFlavor::Mod) {
         Ok(()) => return,
         Err(m) => m,
diff --git a/crates/ra_parser/src/grammar/patterns.rs b/crates/ra_parser/src/grammar/patterns.rs
index 3afbaa82b..936d27575 100644
--- a/crates/ra_parser/src/grammar/patterns.rs
+++ b/crates/ra_parser/src/grammar/patterns.rs
@@ -70,15 +70,6 @@ fn pattern_single_r(p: &mut Parser, recovery_set: TokenSet) {
                 return;
             }
         }
-        // test marco_pat
-        // fn main() {
-        //     let m!(x) = 0;
-        // }
-        if lhs.kind() == PATH_PAT && p.at(T![!]) {
-            let m = lhs.undo_completion(p);
-            items::macro_call_after_excl(p);
-            m.complete(p, MACRO_CALL);
-        }
     }
 }
 
@@ -92,12 +83,12 @@ fn atom_pat(p: &mut Parser, recovery_set: TokenSet) -> Option<CompletedMarker> {
         IDENT => match p.nth(1) {
             // Checks the token after an IDENT to see if a pattern is a path (Struct { .. }) or macro
             // (T![x]).
-            T!['('] | T!['{'] | T![!] => path_pat(p),
-            T![:] if p.nth_at(1, T![::]) => path_pat(p),
+            T!['('] | T!['{'] | T![!] => path_or_macro_pat(p),
+            T![:] if p.nth_at(1, T![::]) => path_or_macro_pat(p),
             _ => bind_pat(p, true),
         },
 
-        _ if paths::is_use_path_start(p) => path_pat(p),
+        _ if paths::is_use_path_start(p) => path_or_macro_pat(p),
         _ if is_literal_pat_start(p) => literal_pat(p),
 
         T![.] if p.at(T![..]) => dot_dot_pat(p),
@@ -146,7 +137,7 @@ fn literal_pat(p: &mut Parser) -> CompletedMarker {
 //     let Bar { .. } = ();
 //     let Bar(..) = ();
 // }
-fn path_pat(p: &mut Parser) -> CompletedMarker {
+fn path_or_macro_pat(p: &mut Parser) -> CompletedMarker {
     assert!(paths::is_use_path_start(p));
     let m = p.start();
     paths::expr_path(p);
@@ -159,6 +150,14 @@ fn path_pat(p: &mut Parser) -> CompletedMarker {
             record_field_pat_list(p);
             RECORD_PAT
         }
+        // test marco_pat
+        // fn main() {
+        //     let m!(x) = 0;
+        // }
+        T![!] => {
+            items::macro_call_after_excl(p);
+            return m.complete(p, MACRO_CALL).precede(p).complete(p, MACRO_PAT);
+        }
         _ => PATH_PAT,
     };
     m.complete(p, kind)
diff --git a/crates/ra_parser/src/syntax_kind/generated.rs b/crates/ra_parser/src/syntax_kind/generated.rs
index dfc30d727..4c16cf1cd 100644
--- a/crates/ra_parser/src/syntax_kind/generated.rs
+++ b/crates/ra_parser/src/syntax_kind/generated.rs
@@ -167,6 +167,7 @@ pub enum SyntaxKind {
     SLICE_PAT,
     RANGE_PAT,
     LITERAL_PAT,
+    MACRO_PAT,
     TUPLE_EXPR,
     ARRAY_EXPR,
     PAREN_EXPR,
diff --git a/crates/ra_syntax/src/ast/generated.rs b/crates/ra_syntax/src/ast/generated.rs
index 7204ca5b1..0c339b987 100644
--- a/crates/ra_syntax/src/ast/generated.rs
+++ b/crates/ra_syntax/src/ast/generated.rs
@@ -2563,6 +2563,38 @@ impl LiteralPat {
     }
 }
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
+pub struct MacroPat {
+    pub(crate) syntax: SyntaxNode,
+}
+impl std::fmt::Display for MacroPat {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        std::fmt::Display::fmt(self.syntax(), f)
+    }
+}
+impl AstNode for MacroPat {
+    fn can_cast(kind: SyntaxKind) -> bool {
+        match kind {
+            MACRO_PAT => true,
+            _ => false,
+        }
+    }
+    fn cast(syntax: SyntaxNode) -> Option<Self> {
+        if Self::can_cast(syntax.kind()) {
+            Some(Self { syntax })
+        } else {
+            None
+        }
+    }
+    fn syntax(&self) -> &SyntaxNode {
+        &self.syntax
+    }
+}
+impl MacroPat {
+    pub fn macro_call(&self) -> Option<MacroCall> {
+        AstChildren::new(&self.syntax).next()
+    }
+}
+#[derive(Debug, Clone, PartialEq, Eq, Hash)]
 pub struct RecordPat {
     pub(crate) syntax: SyntaxNode,
 }
@@ -4600,6 +4632,7 @@ pub enum Pat {
     SlicePat(SlicePat),
     RangePat(RangePat),
     LiteralPat(LiteralPat),
+    MacroPat(MacroPat),
 }
 impl From<OrPat> for Pat {
     fn from(node: OrPat) -> Pat {
@@ -4671,6 +4704,11 @@ impl From<LiteralPat> for Pat {
         Pat::LiteralPat(node)
     }
 }
+impl From<MacroPat> for Pat {
+    fn from(node: MacroPat) -> Pat {
+        Pat::MacroPat(node)
+    }
+}
 impl std::fmt::Display for Pat {
     fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
         std::fmt::Display::fmt(self.syntax(), f)
@@ -4681,7 +4719,7 @@ impl AstNode for Pat {
         match kind {
             OR_PAT | PAREN_PAT | REF_PAT | BOX_PAT | BIND_PAT | PLACEHOLDER_PAT | DOT_DOT_PAT
             | PATH_PAT | RECORD_PAT | TUPLE_STRUCT_PAT | TUPLE_PAT | SLICE_PAT | RANGE_PAT
-            | LITERAL_PAT => true,
+            | LITERAL_PAT | MACRO_PAT => true,
             _ => false,
         }
     }
@@ -4701,6 +4739,7 @@ impl AstNode for Pat {
             SLICE_PAT => Pat::SlicePat(SlicePat { syntax }),
             RANGE_PAT => Pat::RangePat(RangePat { syntax }),
             LITERAL_PAT => Pat::LiteralPat(LiteralPat { syntax }),
+            MACRO_PAT => Pat::MacroPat(MacroPat { syntax }),
             _ => return None,
         };
         Some(res)
@@ -4721,6 +4760,7 @@ impl AstNode for Pat {
             Pat::SlicePat(it) => &it.syntax,
             Pat::RangePat(it) => &it.syntax,
             Pat::LiteralPat(it) => &it.syntax,
+            Pat::MacroPat(it) => &it.syntax,
         }
     }
 }
diff --git a/crates/ra_syntax/test_data/parser/inline/ok/0129_marco_pat.txt b/crates/ra_syntax/test_data/parser/inline/ok/0129_marco_pat.txt
index b05ccc0ed..36d8f4a5f 100644
--- a/crates/ra_syntax/test_data/parser/inline/ok/0129_marco_pat.txt
+++ b/crates/ra_syntax/test_data/parser/inline/ok/0129_marco_pat.txt
@@ -15,16 +15,17 @@ SOURCE_FILE@[0; 33)
         LET_STMT@[16; 30)
           LET_KW@[16; 19) "let"
           WHITESPACE@[19; 20) " "
-          MACRO_CALL@[20; 25)
-            PATH@[20; 21)
-              PATH_SEGMENT@[20; 21)
-                NAME_REF@[20; 21)
-                  IDENT@[20; 21) "m"
-            EXCL@[21; 22) "!"
-            TOKEN_TREE@[22; 25)
-              L_PAREN@[22; 23) "("
-              IDENT@[23; 24) "x"
-              R_PAREN@[24; 25) ")"
+          MACRO_PAT@[20; 25)
+            MACRO_CALL@[20; 25)
+              PATH@[20; 21)
+                PATH_SEGMENT@[20; 21)
+                  NAME_REF@[20; 21)
+                    IDENT@[20; 21) "m"
+              EXCL@[21; 22) "!"
+              TOKEN_TREE@[22; 25)
+                L_PAREN@[22; 23) "("
+                IDENT@[23; 24) "x"
+                R_PAREN@[24; 25) ")"
           WHITESPACE@[25; 26) " "
           EQ@[26; 27) "="
           WHITESPACE@[27; 28) " "
diff --git a/xtask/src/ast_src.rs b/xtask/src/ast_src.rs
index 99bd60198..d9f51ec39 100644
--- a/xtask/src/ast_src.rs
+++ b/xtask/src/ast_src.rs
@@ -138,6 +138,7 @@ pub(crate) const KINDS_SRC: KindsSrc = KindsSrc {
         "SLICE_PAT",
         "RANGE_PAT",
         "LITERAL_PAT",
+        "MACRO_PAT",
         // atoms
         "TUPLE_EXPR",
         "ARRAY_EXPR",
@@ -440,6 +441,7 @@ pub(crate) const AST_SRC: AstSrc = AstSrc {
         struct SlicePat { args: [Pat] }
         struct RangePat {}
         struct LiteralPat { Literal }
+        struct MacroPat { MacroCall }
 
         struct RecordPat { RecordFieldPatList, Path }
         struct RecordFieldPatList {
@@ -622,6 +624,7 @@ pub(crate) const AST_SRC: AstSrc = AstSrc {
             SlicePat,
             RangePat,
             LiteralPat,
+            MacroPat,
         }
 
         enum AttrInput { Literal, TokenTree }