Simplify array parsing

3 files changed, 44 insertions, 68 deletions

diff --git a/crates/ra_parser/src/grammar/attributes.rs b/crates/ra_parser/src/grammar/attributes.rs
index eeae37aef..f3158ade3 100644
--- a/crates/ra_parser/src/grammar/attributes.rs
+++ b/crates/ra_parser/src/grammar/attributes.rs
@@ -8,28 +8,6 @@ pub(super) fn inner_attributes(p: &mut Parser) {
     }
 }
 
-pub(super) fn with_outer_attributes(
-    p: &mut Parser,
-    f: impl Fn(&mut Parser) -> Option<CompletedMarker>,
-) -> bool {
-    let am = p.start();
-    let has_attrs = p.at(T![#]);
-    attributes::outer_attributes(p);
-    let cm = f(p);
-    let success = cm.is_some();
-
-    match (has_attrs, cm) {
-        (true, Some(cm)) => {
-            let kind = cm.kind();
-            cm.undo_completion(p).abandon(p);
-            am.complete(p, kind);
-        }
-        _ => am.abandon(p),
-    }
-
-    success
-}
-
 pub(super) fn outer_attributes(p: &mut Parser) {
     while p.at(T![#]) {
         attribute(p, false)
diff --git a/crates/ra_parser/src/grammar/expressions/atom.rs b/crates/ra_parser/src/grammar/expressions/atom.rs
index 700994e80..5c413317e 100644
--- a/crates/ra_parser/src/grammar/expressions/atom.rs
+++ b/crates/ra_parser/src/grammar/expressions/atom.rs
@@ -181,29 +181,19 @@ fn tuple_expr(p: &mut Parser) -> CompletedMarker {
 fn array_expr(p: &mut Parser) -> CompletedMarker {
     assert!(p.at(T!['[']));
     let m = p.start();
-    p.bump(T!['[']);
-    if p.eat(T![']']) {
-        return m.complete(p, ARRAY_EXPR);
-    }
 
-    // test first_array_member_attributes
-    // pub const A: &[i64] = &[
-    //    #[cfg(test)]
-    //    1,
-    //    2,
-    // ];
-    attributes::with_outer_attributes(p, |p| expr(p).0);
+    let mut n_exprs = 0u32;
+    let mut has_semi = false;
 
-    if p.eat(T![;]) {
-        expr(p);
-        p.expect(T![']']);
-        return m.complete(p, ARRAY_EXPR);
-    }
+    p.bump(T!['[']);
     while !p.at(EOF) && !p.at(T![']']) {
-        p.expect(T![,]);
-        if p.at(T![']']) {
-            break;
-        }
+        n_exprs += 1;
+        // test first_array_member_attributes
+        // pub const A: &[i64] = &[
+        //    #[cfg(test)]
+        //    1,
+        //    2,
+        // ];
 
         // test subsequent_array_member_attributes
         // pub const A: &[i64] = &[
@@ -211,17 +201,32 @@ fn array_expr(p: &mut Parser) -> CompletedMarker {
         //    #[cfg(test)]
         //    2,
         // ];
-        if !attributes::with_outer_attributes(p, |p| {
-            if !p.at_ts(EXPR_FIRST) {
-                p.error("expected expression");
-                return None;
+        let m = p.start();
+        let has_attrs = p.at(T![#]);
+        attributes::outer_attributes(p);
+
+        let cm = expr(p).0;
+
+        match (has_attrs, cm) {
+            (true, Some(cm)) => {
+                let kind = cm.kind();
+                cm.undo_completion(p).abandon(p);
+                m.complete(p, kind);
             }
-            expr(p).0
-        }) {
+            _ => m.abandon(p),
+        }
+
+        if n_exprs == 1 && p.eat(T![;]) {
+            has_semi = true;
+            continue;
+        }
+
+        if has_semi || !p.at(T![']']) && !p.expect(T![,]) {
             break;
         }
     }
     p.expect(T![']']);
+
     m.complete(p, ARRAY_EXPR)
 }
 
diff --git a/crates/ra_syntax/test_data/parser/err/0022_bad_exprs.txt b/crates/ra_syntax/test_data/parser/err/0022_bad_exprs.txt
index ee0ac52c3..310a82464 100644
--- a/crates/ra_syntax/test_data/parser/err/0022_bad_exprs.txt
+++ b/crates/ra_syntax/test_data/parser/err/0022_bad_exprs.txt
@@ -12,8 +12,8 @@ SOURCE_FILE@[0; 112)
       BLOCK@[7; 33)
         L_CURLY@[7; 8) "{"
         WHITESPACE@[8; 9) " "
-        EXPR_STMT@[9; 15)
-          ARRAY_EXPR@[9; 15)
+        EXPR_STMT@[9; 26)
+          ARRAY_EXPR@[9; 26)
             L_BRACK@[9; 10) "["
             LITERAL@[10; 11)
               INT_NUMBER@[10; 11) "1"
@@ -22,17 +22,13 @@ SOURCE_FILE@[0; 112)
             LITERAL@[13; 14)
               INT_NUMBER@[13; 14) "2"
             COMMA@[14; 15) ","
-        WHITESPACE@[15; 16) " "
-        EXPR_STMT@[16; 17)
-          ERROR@[16; 17)
-            AT@[16; 17) "@"
-        EXPR_STMT@[17; 18)
-          ERROR@[17; 18)
+            WHITESPACE@[15; 16) " "
+            ERROR@[16; 17)
+              AT@[16; 17) "@"
             COMMA@[17; 18) ","
-        WHITESPACE@[18; 19) " "
-        STRUCT_DEF@[19; 26)
-          STRUCT_KW@[19; 25) "struct"
-          ERROR@[25; 26)
+            WHITESPACE@[18; 19) " "
+            ERROR@[19; 25)
+              STRUCT_KW@[19; 25) "struct"
             COMMA@[25; 26) ","
         WHITESPACE@[26; 27) " "
         LET_STMT@[27; 31)
@@ -151,15 +147,12 @@ SOURCE_FILE@[0; 112)
         WHITESPACE@[109; 110) " "
         R_CURLY@[110; 111) "}"
   WHITESPACE@[111; 112) "\n"
-error 15: expected expression
-error 15: expected R_BRACK
-error 15: expected SEMI
 error 16: expected expression
-error 17: expected SEMI
-error 17: expected expression
-error 18: expected SEMI
-error 25: expected a name
-error 26: expected `;`, `{`, or `(`
+error 19: expected expression
+error 26: expected expression
+error 26: expected COMMA
+error 26: expected R_BRACK
+error 26: expected SEMI
 error 30: expected pattern
 error 31: expected SEMI
 error 52: expected expression