Introduce EffectExpr

Author: matklad

crates/ra_assists/src/handlers/early_return.rs

@@ -2,7 +2,7 @@ use std::{iter::once, ops::RangeInclusive};
 
 use ra_syntax::{
     algo::replace_children,
-    ast::{self, edit::IndentLevel, make, Block, Pat::TupleStructPat},
+    ast::{self, edit::IndentLevel, make},
     AstNode,
     SyntaxKind::{FN_DEF, LOOP_EXPR, L_CURLY, R_CURLY, WHILE_EXPR, WHITESPACE},
     SyntaxNode,
@@ -47,7 +47,7 @@ pub(crate) fn convert_to_guarded_return(ctx: AssistCtx) -> Option<Assist> {
     // Check if there is an IfLet that we can handle.
     let if_let_pat = match cond.pat() {
         None => None, // No IfLet, supported.
-        Some(TupleStructPat(pat)) if pat.args().count() == 1 => {
+        Some(ast::Pat::TupleStructPat(pat)) if pat.args().count() == 1 => {
             let path = pat.path()?;
             match path.qualifier() {
                 None => {
@@ -61,9 +61,9 @@ pub(crate) fn convert_to_guarded_return(ctx: AssistCtx) -> Option<Assist> {
     };
 
     let cond_expr = cond.expr()?;
-    let then_block = if_expr.then_branch()?.block()?;
+    let then_block = if_expr.then_branch()?;
 
-    let parent_block = if_expr.syntax().parent()?.ancestors().find_map(ast::Block::cast)?;
+    let parent_block = if_expr.syntax().parent()?.ancestors().find_map(ast::BlockExpr::cast)?;
 
     if parent_block.expr()? != if_expr.clone().into() {
         return None;
@@ -80,7 +80,7 @@ pub(crate) fn convert_to_guarded_return(ctx: AssistCtx) -> Option<Assist> {
         return None;
     }
 
-    let parent_container = parent_block.syntax().parent()?.parent()?;
+    let parent_container = parent_block.syntax().parent()?;
 
     let early_expression: ast::Expr = match parent_container.kind() {
         WHILE_EXPR | LOOP_EXPR => make::expr_continue(),
@@ -144,13 +144,13 @@ pub(crate) fn convert_to_guarded_return(ctx: AssistCtx) -> Option<Assist> {
             }
         };
         edit.target(if_expr.syntax().text_range());
-        edit.replace_ast(parent_block, ast::Block::cast(new_block).unwrap());
+        edit.replace_ast(parent_block, ast::BlockExpr::cast(new_block).unwrap());
         edit.set_cursor(cursor_position);
 
         fn replace(
             new_expr: &SyntaxNode,
-            then_block: &Block,
-            parent_block: &Block,
+            then_block: &ast::BlockExpr,
+            parent_block: &ast::BlockExpr,
             if_expr: &ast::IfExpr,
         ) -> SyntaxNode {
             let then_block_items = IndentLevel::from(1).decrease_indent(then_block.clone());

crates/ra_assists/src/handlers/inline_local_variable.rs

@@ -89,6 +89,7 @@ pub(crate) fn inline_local_variable(ctx: AssistCtx) -> Option<Assist> {
             | (ast::Expr::ParenExpr(_), _)
             | (ast::Expr::PathExpr(_), _)
             | (ast::Expr::BlockExpr(_), _)
+            | (ast::Expr::EffectExpr(_), _)
             | (_, ast::Expr::CallExpr(_))
             | (_, ast::Expr::TupleExpr(_))
             | (_, ast::Expr::ArrayExpr(_))

crates/ra_assists/src/handlers/introduce_variable.rs

@@ -111,7 +111,7 @@ fn valid_target_expr(node: SyntaxNode) -> Option<ast::Expr> {
 /// expression like a lambda or match arm.
 fn anchor_stmt(expr: ast::Expr) -> Option<(SyntaxNode, bool)> {
     expr.syntax().ancestors().find_map(|node| {
-        if let Some(expr) = node.parent().and_then(ast::Block::cast).and_then(|it| it.expr()) {
+        if let Some(expr) = node.parent().and_then(ast::BlockExpr::cast).and_then(|it| it.expr()) {
             if expr.syntax() == &node {
                 tested_by!(test_introduce_var_last_expr);
                 return Some((node, false));

crates/ra_assists/src/handlers/move_guard.rs

@@ -113,9 +113,9 @@ pub(crate) fn move_arm_cond_to_match_guard(ctx: AssistCtx) -> Option<Assist> {
         "Move condition to match guard",
         |edit| {
             edit.target(if_expr.syntax().text_range());
-            let then_only_expr = then_block.block().and_then(|it| it.statements().next()).is_none();
+            let then_only_expr = then_block.statements().next().is_none();
 
-            match &then_block.block().and_then(|it| it.expr()) {
+            match &then_block.expr() {
                 Some(then_expr) if then_only_expr => {
                     edit.replace(if_expr.syntax().text_range(), then_expr.syntax().text())
                 }

crates/ra_fmt/src/lib.rs

@@ -42,7 +42,6 @@ pub fn unwrap_trivial_block(block: ast::BlockExpr) -> ast::Expr {
 }
 
 pub fn extract_trivial_expression(block: &ast::BlockExpr) -> Option<ast::Expr> {
-    let block = block.block()?;
     let has_anything_else = |thing: &SyntaxNode| -> bool {
         let mut non_trivial_children =
             block.syntax().children_with_tokens().filter(|it| match it.kind() {

crates/ra_hir_def/src/body/lower.rs

@@ -203,10 +203,16 @@ impl ExprCollector<'_> {
 
                 self.alloc_expr(Expr::If { condition, then_branch, else_branch }, syntax_ptr)
             }
-            ast::Expr::TryBlockExpr(e) => {
-                let body = self.collect_block_opt(e.body());
-                self.alloc_expr(Expr::TryBlock { body }, syntax_ptr)
-            }
+            ast::Expr::EffectExpr(e) => match e.effect() {
+                ast::Effect::Try(_) => {
+                    let body = self.collect_block_opt(e.block_expr());
+                    self.alloc_expr(Expr::TryBlock { body }, syntax_ptr)
+                }
+                // FIXME: we need to record these effects somewhere...
+                ast::Effect::Async(_) | ast::Effect::Label(_) | ast::Effect::Unsafe(_) => {
+                    self.collect_block_opt(e.block_expr())
+                }
+            },
             ast::Expr::BlockExpr(e) => self.collect_block(e),
             ast::Expr::LoopExpr(e) => {
                 let body = self.collect_block_opt(e.loop_body());
@@ -494,12 +500,8 @@ impl ExprCollector<'_> {
         }
     }
 
-    fn collect_block(&mut self, expr: ast::BlockExpr) -> ExprId {
-        let syntax_node_ptr = AstPtr::new(&expr.clone().into());
-        let block = match expr.block() {
-            Some(block) => block,
-            None => return self.alloc_expr(Expr::Missing, syntax_node_ptr),
-        };
+    fn collect_block(&mut self, block: ast::BlockExpr) -> ExprId {
+        let syntax_node_ptr = AstPtr::new(&block.clone().into());
         self.collect_block_items(&block);
         let statements = block
             .statements()
@@ -517,7 +519,7 @@ impl ExprCollector<'_> {
         self.alloc_expr(Expr::Block { statements, tail }, syntax_node_ptr)
     }
 
-    fn collect_block_items(&mut self, block: &ast::Block) {
+    fn collect_block_items(&mut self, block: &ast::BlockExpr) {
         let container = ContainerId::DefWithBodyId(self.def);
         for item in block.items() {
             let (def, name): (ModuleDefId, Option<ast::Name>) = match item {

crates/ra_hir_expand/src/db.rs

@@ -330,7 +330,7 @@ fn to_fragment_kind(db: &dyn AstDatabase, id: MacroCallId) -> FragmentKind {
             FragmentKind::Expr
         }
         // FIXME: Expand to statements in appropriate positions; HIR lowering needs to handle that
-        EXPR_STMT | BLOCK => FragmentKind::Expr,
+        EXPR_STMT | BLOCK_EXPR => FragmentKind::Expr,
         ARG_LIST => FragmentKind::Expr,
         TRY_EXPR => FragmentKind::Expr,
         TUPLE_EXPR => FragmentKind::Expr,
@@ -342,7 +342,6 @@ fn to_fragment_kind(db: &dyn AstDatabase, id: MacroCallId) -> FragmentKind {
         CONDITION => FragmentKind::Expr,
         BREAK_EXPR => FragmentKind::Expr,
         RETURN_EXPR => FragmentKind::Expr,
-        BLOCK_EXPR => FragmentKind::Expr,
         MATCH_EXPR => FragmentKind::Expr,
         MATCH_ARM => FragmentKind::Expr,
         MATCH_GUARD => FragmentKind::Expr,

crates/ra_ide/src/completion/completion_context.rs

@@ -344,7 +344,7 @@ impl<'a> CompletionContext<'a> {
                                 stmt.syntax().text_range() == name_ref.syntax().text_range(),
                             );
                         }
-                        if let Some(block) = ast::Block::cast(node) {
+                        if let Some(block) = ast::BlockExpr::cast(node) {
                             return Some(
                                 block.expr().map(|e| e.syntax().text_range())
                                     == Some(name_ref.syntax().text_range()),

crates/ra_ide/src/folding_ranges.rs

@@ -88,7 +88,7 @@ fn fold_kind(kind: SyntaxKind) -> Option<FoldKind> {
         | ITEM_LIST
         | EXTERN_ITEM_LIST
         | USE_TREE_LIST
-        | BLOCK
+        | BLOCK_EXPR
         | MATCH_ARM_LIST
         | ENUM_VARIANT_LIST
         | TOKEN_TREE => Some(FoldKind::Block),

crates/ra_ide/src/join_lines.rs

@@ -129,8 +129,7 @@ fn has_comma_after(node: &SyntaxNode) -> bool {
 }
 
 fn join_single_expr_block(edit: &mut TextEditBuilder, token: &SyntaxToken) -> Option<()> {
-    let block = ast::Block::cast(token.parent())?;
-    let block_expr = ast::BlockExpr::cast(block.syntax().parent()?)?;
+    let block_expr = ast::BlockExpr::cast(token.parent())?;
     if !block_expr.is_standalone() {
         return None;
     }