4 files changed, 35 insertions, 52 deletions

diff --git a/crates/ra_syntax/src/ast/expr_extensions.rs b/crates/ra_syntax/src/ast/expr_extensions.rs
index 1c1134bc5..329c80749 100644
--- a/crates/ra_syntax/src/ast/expr_extensions.rs
+++ b/crates/ra_syntax/src/ast/expr_extensions.rs
@@ -16,7 +16,7 @@ impl ast::Expr {
             | ast::Expr::WhileExpr(_)
             | ast::Expr::BlockExpr(_)
             | ast::Expr::MatchExpr(_)
-            | ast::Expr::TryBlockExpr(_) => true,
+            | ast::Expr::TryExpr(_) => true,
             _ => false,
         }
     }
@@ -359,7 +359,22 @@ impl ast::Literal {
     }
 }
 
+pub enum BlockModifier {
+    Async(SyntaxToken),
+    Unsafe(SyntaxToken),
+}
+
 impl ast::BlockExpr {
+    pub fn modifier(&self) -> Option<BlockModifier> {
+        if let Some(token) = self.async_token() {
+            return Some(BlockModifier::Async(token));
+        }
+        if let Some(token) = self.unsafe_token() {
+            return Some(BlockModifier::Unsafe(token));
+        }
+        None
+    }
+
     /// false if the block is an intrinsic part of the syntax and can't be
     /// replaced with arbitrary expression.
     ///
@@ -368,12 +383,15 @@ impl ast::BlockExpr {
     /// const FOO: () = { stand_alone };
     /// ```
     pub fn is_standalone(&self) -> bool {
-        let kind = match self.syntax().parent() {
+        if self.modifier().is_some() {
+            return false;
+        }
+        let parent = match self.syntax().parent() {
+            Some(it) => it,
             None => return true,
-            Some(it) => it.kind(),
         };
-        match kind {
-            FN_DEF | MATCH_ARM | IF_EXPR | WHILE_EXPR | LOOP_EXPR | TRY_BLOCK_EXPR => false,
+        match parent.kind() {
+            FN_DEF | IF_EXPR | WHILE_EXPR | LOOP_EXPR => false,
             _ => true,
         }
     }
diff --git a/crates/ra_syntax/src/ast/generated/nodes.rs b/crates/ra_syntax/src/ast/generated/nodes.rs
index 2cb3ad011..81260680f 100644
--- a/crates/ra_syntax/src/ast/generated/nodes.rs
+++ b/crates/ra_syntax/src/ast/generated/nodes.rs
@@ -476,16 +476,6 @@ impl LoopExpr {
 }
 
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
-pub struct TryBlockExpr {
-    pub(crate) syntax: SyntaxNode,
-}
-impl ast::AttrsOwner for TryBlockExpr {}
-impl TryBlockExpr {
-    pub fn try_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![try]) }
-    pub fn body(&self) -> Option<BlockExpr> { support::child(&self.syntax) }
-}
-
-#[derive(Debug, Clone, PartialEq, Eq, Hash)]
 pub struct ForExpr {
     pub(crate) syntax: SyntaxNode,
 }
@@ -554,6 +544,7 @@ impl ast::AttrsOwner for BlockExpr {}
 impl BlockExpr {
     pub fn label(&self) -> Option<Label> { support::child(&self.syntax) }
     pub fn unsafe_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![unsafe]) }
+    pub fn async_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![async]) }
     pub fn block(&self) -> Option<Block> { support::child(&self.syntax) }
 }
 
@@ -1249,6 +1240,7 @@ pub struct PathSegment {
 }
 impl PathSegment {
     pub fn coloncolon_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![::]) }
+    pub fn crate_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![crate]) }
     pub fn l_angle_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![<]) }
     pub fn name_ref(&self) -> Option<NameRef> { support::child(&self.syntax) }
     pub fn type_arg_list(&self) -> Option<TypeArgList> { support::child(&self.syntax) }
@@ -1473,7 +1465,6 @@ pub enum Expr {
     FieldExpr(FieldExpr),
     AwaitExpr(AwaitExpr),
     TryExpr(TryExpr),
-    TryBlockExpr(TryBlockExpr),
     CastExpr(CastExpr),
     RefExpr(RefExpr),
     PrefixExpr(PrefixExpr),
@@ -1956,17 +1947,6 @@ impl AstNode for LoopExpr {
     }
     fn syntax(&self) -> &SyntaxNode { &self.syntax }
 }
-impl AstNode for TryBlockExpr {
-    fn can_cast(kind: SyntaxKind) -> bool { kind == TRY_BLOCK_EXPR }
-    fn cast(syntax: SyntaxNode) -> Option<Self> {
-        if Self::can_cast(syntax.kind()) {
-            Some(Self { syntax })
-        } else {
-            None
-        }
-    }
-    fn syntax(&self) -> &SyntaxNode { &self.syntax }
-}
 impl AstNode for ForExpr {
     fn can_cast(kind: SyntaxKind) -> bool { kind == FOR_EXPR }
     fn cast(syntax: SyntaxNode) -> Option<Self> {
@@ -3308,9 +3288,6 @@ impl From<AwaitExpr> for Expr {
 impl From<TryExpr> for Expr {
     fn from(node: TryExpr) -> Expr { Expr::TryExpr(node) }
 }
-impl From<TryBlockExpr> for Expr {
-    fn from(node: TryBlockExpr) -> Expr { Expr::TryBlockExpr(node) }
-}
 impl From<CastExpr> for Expr {
     fn from(node: CastExpr) -> Expr { Expr::CastExpr(node) }
 }
@@ -3341,9 +3318,8 @@ impl AstNode for Expr {
             TUPLE_EXPR | ARRAY_EXPR | PAREN_EXPR | PATH_EXPR | LAMBDA_EXPR | IF_EXPR
             | LOOP_EXPR | FOR_EXPR | WHILE_EXPR | CONTINUE_EXPR | BREAK_EXPR | LABEL
             | BLOCK_EXPR | RETURN_EXPR | MATCH_EXPR | RECORD_LIT | CALL_EXPR | INDEX_EXPR
-            | METHOD_CALL_EXPR | FIELD_EXPR | AWAIT_EXPR | TRY_EXPR | TRY_BLOCK_EXPR
-            | CAST_EXPR | REF_EXPR | PREFIX_EXPR | RANGE_EXPR | BIN_EXPR | LITERAL | MACRO_CALL
-            | BOX_EXPR => true,
+            | METHOD_CALL_EXPR | FIELD_EXPR | AWAIT_EXPR | TRY_EXPR | CAST_EXPR | REF_EXPR
+            | PREFIX_EXPR | RANGE_EXPR | BIN_EXPR | LITERAL | MACRO_CALL | BOX_EXPR => true,
             _ => false,
         }
     }
@@ -3371,7 +3347,6 @@ impl AstNode for Expr {
             FIELD_EXPR => Expr::FieldExpr(FieldExpr { syntax }),
             AWAIT_EXPR => Expr::AwaitExpr(AwaitExpr { syntax }),
             TRY_EXPR => Expr::TryExpr(TryExpr { syntax }),
-            TRY_BLOCK_EXPR => Expr::TryBlockExpr(TryBlockExpr { syntax }),
             CAST_EXPR => Expr::CastExpr(CastExpr { syntax }),
             REF_EXPR => Expr::RefExpr(RefExpr { syntax }),
             PREFIX_EXPR => Expr::PrefixExpr(PrefixExpr { syntax }),
@@ -3408,7 +3383,6 @@ impl AstNode for Expr {
             Expr::FieldExpr(it) => &it.syntax,
             Expr::AwaitExpr(it) => &it.syntax,
             Expr::TryExpr(it) => &it.syntax,
-            Expr::TryBlockExpr(it) => &it.syntax,
             Expr::CastExpr(it) => &it.syntax,
             Expr::RefExpr(it) => &it.syntax,
             Expr::PrefixExpr(it) => &it.syntax,
@@ -3889,11 +3863,6 @@ impl std::fmt::Display for LoopExpr {
         std::fmt::Display::fmt(self.syntax(), f)
     }
 }
-impl std::fmt::Display for TryBlockExpr {
-    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
-        std::fmt::Display::fmt(self.syntax(), f)
-    }
-}
 impl std::fmt::Display for ForExpr {
     fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
         std::fmt::Display::fmt(self.syntax(), f)
diff --git a/crates/ra_syntax/src/ast/make.rs b/crates/ra_syntax/src/ast/make.rs
index ee0f5cc40..492088353 100644
--- a/crates/ra_syntax/src/ast/make.rs
+++ b/crates/ra_syntax/src/ast/make.rs
@@ -22,8 +22,7 @@ pub fn path_unqualified(segment: ast::PathSegment) -> ast::Path {
 pub fn path_qualified(qual: ast::Path, segment: ast::PathSegment) -> ast::Path {
     path_from_text(&format!("{}::{}", qual, segment))
 }
-
-pub fn path_from_text(text: &str) -> ast::Path {
+fn path_from_text(text: &str) -> ast::Path {
     ast_from_text(text)
 }
 
diff --git a/crates/ra_syntax/src/ast/tokens.rs b/crates/ra_syntax/src/ast/tokens.rs
index 3865729b8..74906d8a6 100644
--- a/crates/ra_syntax/src/ast/tokens.rs
+++ b/crates/ra_syntax/src/ast/tokens.rs
@@ -13,7 +13,12 @@ impl Comment {
     }
 
     pub fn prefix(&self) -> &'static str {
-        prefix_by_kind(self.kind())
+        for (prefix, k) in COMMENT_PREFIX_TO_KIND.iter() {
+            if *k == self.kind() && self.text().starts_with(prefix) {
+                return prefix;
+            }
+        }
+        unreachable!()
     }
 }
 
@@ -48,6 +53,7 @@ pub enum CommentPlacement {
 const COMMENT_PREFIX_TO_KIND: &[(&str, CommentKind)] = {
     use {CommentPlacement::*, CommentShape::*};
     &[
+        ("////", CommentKind { shape: Line, doc: None }),
         ("///", CommentKind { shape: Line, doc: Some(Outer) }),
         ("//!", CommentKind { shape: Line, doc: Some(Inner) }),
         ("/**", CommentKind { shape: Block, doc: Some(Outer) }),
@@ -69,15 +75,6 @@ fn kind_by_prefix(text: &str) -> CommentKind {
     panic!("bad comment text: {:?}", text)
 }
 
-fn prefix_by_kind(kind: CommentKind) -> &'static str {
-    for (prefix, k) in COMMENT_PREFIX_TO_KIND.iter() {
-        if *k == kind {
-            return prefix;
-        }
-    }
-    unreachable!()
-}
-
 impl Whitespace {
     pub fn spans_multiple_lines(&self) -> bool {
         let text = self.text();