Introduce EffectExpr

7 files changed, 73 insertions, 76 deletions

diff --git a/crates/ra_syntax/src/ast.rs b/crates/ra_syntax/src/ast.rs
index a716e525b..1876afe95 100644
--- a/crates/ra_syntax/src/ast.rs
+++ b/crates/ra_syntax/src/ast.rs
@@ -16,7 +16,7 @@ use crate::{
 };
 
 pub use self::{
-    expr_extensions::{ArrayExprKind, BinOp, ElseBranch, LiteralKind, PrefixOp, RangeOp},
+    expr_extensions::{ArrayExprKind, BinOp, Effect, ElseBranch, LiteralKind, PrefixOp, RangeOp},
     extensions::{
         AttrKind, FieldKind, NameOrNameRef, PathSegmentKind, SelfParamKind, SlicePatComponents,
         StructKind, TypeBoundKind, VisibilityKind,
diff --git a/crates/ra_syntax/src/ast/edit.rs b/crates/ra_syntax/src/ast/edit.rs
index 26e4576ff..c507dc683 100644
--- a/crates/ra_syntax/src/ast/edit.rs
+++ b/crates/ra_syntax/src/ast/edit.rs
@@ -28,7 +28,7 @@ impl ast::BinExpr {
 
 impl ast::FnDef {
     #[must_use]
-    pub fn with_body(&self, body: ast::Block) -> ast::FnDef {
+    pub fn with_body(&self, body: ast::BlockExpr) -> ast::FnDef {
         let mut to_insert: ArrayVec<[SyntaxElement; 2]> = ArrayVec::new();
         let old_body_or_semi: SyntaxElement = if let Some(old_body) = self.body() {
             old_body.syntax().clone().into()
diff --git a/crates/ra_syntax/src/ast/expr_extensions.rs b/crates/ra_syntax/src/ast/expr_extensions.rs
index ecf74fd36..7ee36e60c 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::EffectExpr(_) => true,
             _ => false,
         }
     }
@@ -359,6 +359,33 @@ impl ast::Literal {
     }
 }
 
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub enum Effect {
+    Async(SyntaxToken),
+    Unsafe(SyntaxToken),
+    Try(SyntaxToken),
+    // Very much not an effect, but we stuff it into this node anyway
+    Label(ast::Label),
+}
+
+impl ast::EffectExpr {
+    pub fn effect(&self) -> Effect {
+        if let Some(token) = self.async_token() {
+            return Effect::Async(token);
+        }
+        if let Some(token) = self.unsafe_token() {
+            return Effect::Unsafe(token);
+        }
+        if let Some(token) = self.try_token() {
+            return Effect::Try(token);
+        }
+        if let Some(label) = self.label() {
+            return Effect::Label(label);
+        }
+        unreachable!("ast::EffectExpr without Effect")
+    }
+}
+
 impl ast::BlockExpr {
     /// false if the block is an intrinsic part of the syntax and can't be
     /// replaced with arbitrary expression.
@@ -368,15 +395,12 @@ impl ast::BlockExpr {
     /// const FOO: () = { stand_alone };
     /// ```
     pub fn is_standalone(&self) -> bool {
-        if self.unsafe_token().is_some() || self.async_token().is_some() {
-            return false;
-        }
-        let kind = match self.syntax().parent() {
+        let parent = match self.syntax().parent() {
+            Some(it) => it,
             None => return true,
-            Some(it) => it.kind(),
         };
-        match kind {
-            FN_DEF | IF_EXPR | WHILE_EXPR | LOOP_EXPR | TRY_BLOCK_EXPR => false,
+        match parent.kind() {
+            FN_DEF | IF_EXPR | WHILE_EXPR | LOOP_EXPR | EFFECT_EXPR => false,
             _ => true,
         }
     }
diff --git a/crates/ra_syntax/src/ast/generated/nodes.rs b/crates/ra_syntax/src/ast/generated/nodes.rs
index 2096f12f1..5e844d5ae 100644
--- a/crates/ra_syntax/src/ast/generated/nodes.rs
+++ b/crates/ra_syntax/src/ast/generated/nodes.rs
@@ -476,13 +476,16 @@ impl LoopExpr {
 }
 
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
-pub struct TryBlockExpr {
+pub struct EffectExpr {
     pub(crate) syntax: SyntaxNode,
 }
-impl ast::AttrsOwner for TryBlockExpr {}
-impl TryBlockExpr {
+impl ast::AttrsOwner for EffectExpr {}
+impl EffectExpr {
+    pub fn label(&self) -> Option<Label> { support::child(&self.syntax) }
     pub fn try_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![try]) }
-    pub fn body(&self) -> Option<BlockExpr> { 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_expr(&self) -> Option<BlockExpr> { support::child(&self.syntax) }
 }
 
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
@@ -551,11 +554,12 @@ pub struct BlockExpr {
     pub(crate) syntax: SyntaxNode,
 }
 impl ast::AttrsOwner for BlockExpr {}
+impl ast::ModuleItemOwner 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) }
+    pub fn l_curly_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['{']) }
+    pub fn statements(&self) -> AstChildren<Stmt> { support::children(&self.syntax) }
+    pub fn expr(&self) -> Option<Expr> { support::child(&self.syntax) }
+    pub fn r_curly_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['}']) }
 }
 
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
@@ -627,8 +631,8 @@ pub struct TryExpr {
 }
 impl ast::AttrsOwner for TryExpr {}
 impl TryExpr {
-    pub fn try_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![try]) }
     pub fn expr(&self) -> Option<Expr> { support::child(&self.syntax) }
+    pub fn question_mark_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T![?]) }
 }
 
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
@@ -1122,19 +1126,6 @@ impl Condition {
 }
 
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
-pub struct Block {
-    pub(crate) syntax: SyntaxNode,
-}
-impl ast::AttrsOwner for Block {}
-impl ast::ModuleItemOwner for Block {}
-impl Block {
-    pub fn l_curly_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['{']) }
-    pub fn statements(&self) -> AstChildren<Stmt> { support::children(&self.syntax) }
-    pub fn expr(&self) -> Option<Expr> { support::child(&self.syntax) }
-    pub fn r_curly_token(&self) -> Option<SyntaxToken> { support::token(&self.syntax, T!['}']) }
-}
-
-#[derive(Debug, Clone, PartialEq, Eq, Hash)]
 pub struct ParamList {
     pub(crate) syntax: SyntaxNode,
 }
@@ -1477,7 +1468,7 @@ pub enum Expr {
     FieldExpr(FieldExpr),
     AwaitExpr(AwaitExpr),
     TryExpr(TryExpr),
-    TryBlockExpr(TryBlockExpr),
+    EffectExpr(EffectExpr),
     CastExpr(CastExpr),
     RefExpr(RefExpr),
     PrefixExpr(PrefixExpr),
@@ -1960,8 +1951,8 @@ impl AstNode for LoopExpr {
     }
     fn syntax(&self) -> &SyntaxNode { &self.syntax }
 }
-impl AstNode for TryBlockExpr {
-    fn can_cast(kind: SyntaxKind) -> bool { kind == TRY_BLOCK_EXPR }
+impl AstNode for EffectExpr {
+    fn can_cast(kind: SyntaxKind) -> bool { kind == EFFECT_EXPR }
     fn cast(syntax: SyntaxNode) -> Option<Self> {
         if Self::can_cast(syntax.kind()) {
             Some(Self { syntax })
@@ -2653,17 +2644,6 @@ impl AstNode for Condition {
     }
     fn syntax(&self) -> &SyntaxNode { &self.syntax }
 }
-impl AstNode for Block {
-    fn can_cast(kind: SyntaxKind) -> bool { kind == BLOCK }
-    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 ParamList {
     fn can_cast(kind: SyntaxKind) -> bool { kind == PARAM_LIST }
     fn cast(syntax: SyntaxNode) -> Option<Self> {
@@ -3312,8 +3292,8 @@ 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<EffectExpr> for Expr {
+    fn from(node: EffectExpr) -> Expr { Expr::EffectExpr(node) }
 }
 impl From<CastExpr> for Expr {
     fn from(node: CastExpr) -> Expr { Expr::CastExpr(node) }
@@ -3345,9 +3325,10 @@ 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 | EFFECT_EXPR | CAST_EXPR
+            | REF_EXPR | PREFIX_EXPR | RANGE_EXPR | BIN_EXPR | LITERAL | MACRO_CALL | BOX_EXPR => {
+                true
+            }
             _ => false,
         }
     }
@@ -3375,7 +3356,7 @@ 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 }),
+            EFFECT_EXPR => Expr::EffectExpr(EffectExpr { syntax }),
             CAST_EXPR => Expr::CastExpr(CastExpr { syntax }),
             REF_EXPR => Expr::RefExpr(RefExpr { syntax }),
             PREFIX_EXPR => Expr::PrefixExpr(PrefixExpr { syntax }),
@@ -3412,7 +3393,7 @@ 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::EffectExpr(it) => &it.syntax,
             Expr::CastExpr(it) => &it.syntax,
             Expr::RefExpr(it) => &it.syntax,
             Expr::PrefixExpr(it) => &it.syntax,
@@ -3893,7 +3874,7 @@ impl std::fmt::Display for LoopExpr {
         std::fmt::Display::fmt(self.syntax(), f)
     }
 }
-impl std::fmt::Display for TryBlockExpr {
+impl std::fmt::Display for EffectExpr {
     fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
         std::fmt::Display::fmt(self.syntax(), f)
     }
@@ -4208,11 +4189,6 @@ impl std::fmt::Display for Condition {
         std::fmt::Display::fmt(self.syntax(), f)
     }
 }
-impl std::fmt::Display for Block {
-    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
-        std::fmt::Display::fmt(self.syntax(), f)
-    }
-}
 impl std::fmt::Display for ParamList {
     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 492088353..b9a396cad 100644
--- a/crates/ra_syntax/src/ast/make.rs
+++ b/crates/ra_syntax/src/ast/make.rs
@@ -82,10 +82,10 @@ pub fn block_expr(
     ast_from_text(&format!("fn f() {}", buf))
 }
 
-pub fn block_from_expr(e: ast::Expr) -> ast::Block {
+pub fn block_from_expr(e: ast::Expr) -> ast::BlockExpr {
     return from_text(&format!("{{ {} }}", e));
 
-    fn from_text(text: &str) -> ast::Block {
+    fn from_text(text: &str) -> ast::BlockExpr {
         ast_from_text(&format!("fn f() {}", text))
     }
 }
diff --git a/crates/ra_syntax/src/lib.rs b/crates/ra_syntax/src/lib.rs
index ceeb2bde9..d0234cada 100644
--- a/crates/ra_syntax/src/lib.rs
+++ b/crates/ra_syntax/src/lib.rs
@@ -237,8 +237,7 @@ fn api_walkthrough() {
 
     // Let's get the `1 + 1` expression!
     let body: ast::BlockExpr = func.body().unwrap();
-    let block = body.block().unwrap();
-    let expr: ast::Expr = block.expr().unwrap();
+    let expr: ast::Expr = body.expr().unwrap();
 
     // Enums are used to group related ast nodes together, and can be used for
     // matching. However, because there are no public fields, it's possible to
@@ -274,8 +273,8 @@ fn api_walkthrough() {
     assert_eq!(text.to_string(), "1 + 1");
 
     // There's a bunch of traversal methods on `SyntaxNode`:
-    assert_eq!(expr_syntax.parent().as_ref(), Some(block.syntax()));
-    assert_eq!(block.syntax().first_child_or_token().map(|it| it.kind()), Some(T!['{']));
+    assert_eq!(expr_syntax.parent().as_ref(), Some(body.syntax()));
+    assert_eq!(body.syntax().first_child_or_token().map(|it| it.kind()), Some(T!['{']));
     assert_eq!(
         expr_syntax.next_sibling_or_token().map(|it| it.kind()),
         Some(SyntaxKind::WHITESPACE)
diff --git a/crates/ra_syntax/src/validation/block.rs b/crates/ra_syntax/src/validation/block.rs
index 8e962ab5b..2c08f7e6e 100644
--- a/crates/ra_syntax/src/validation/block.rs
+++ b/crates/ra_syntax/src/validation/block.rs
@@ -6,19 +6,17 @@ use crate::{
     SyntaxKind::*,
 };
 
-pub(crate) fn validate_block_expr(expr: ast::BlockExpr, errors: &mut Vec<SyntaxError>) {
-    if let Some(parent) = expr.syntax().parent() {
+pub(crate) fn validate_block_expr(block: ast::BlockExpr, errors: &mut Vec<SyntaxError>) {
+    if let Some(parent) = block.syntax().parent() {
         match parent.kind() {
-            FN_DEF | EXPR_STMT | BLOCK => return,
+            FN_DEF | EXPR_STMT | BLOCK_EXPR => return,
             _ => {}
         }
     }
-    if let Some(block) = expr.block() {
-        errors.extend(block.attrs().map(|attr| {
-            SyntaxError::new(
-                "A block in this position cannot accept inner attributes",
-                attr.syntax().text_range(),
-            )
-        }))
-    }
+    errors.extend(block.attrs().map(|attr| {
+        SyntaxError::new(
+            "A block in this position cannot accept inner attributes",
+            attr.syntax().text_range(),
+        )
+    }))
 }