5 files changed, 157 insertions, 163 deletions

diff --git a/crates/ra_assists/src/handlers/change_return_type_to_result.rs b/crates/ra_assists/src/handlers/change_return_type_to_result.rs
index d5a68a24c..be480943c 100644
--- a/crates/ra_assists/src/handlers/change_return_type_to_result.rs
+++ b/crates/ra_assists/src/handlers/change_return_type_to_result.rs
@@ -1,10 +1,12 @@
+use std::iter;
+
 use syntax::{
-    ast::{self, BlockExpr, Expr, LoopBodyOwner},
+    ast::{self, make, BlockExpr, Expr, LoopBodyOwner},
     AstNode, SyntaxNode,
 };
+use test_utils::mark;
 
 use crate::{AssistContext, AssistId, AssistKind, Assists};
-use test_utils::mark;
 
 // Assist: change_return_type_to_result
 //
@@ -44,7 +46,13 @@ pub(crate) fn change_return_type_to_result(acc: &mut Assists, ctx: &AssistContex
             tail_return_expr_collector.collect_tail_exprs(block_expr);
 
             for ret_expr_arg in tail_return_expr_collector.exprs_to_wrap {
-                builder.replace_node_and_indent(&ret_expr_arg, format!("Ok({})", ret_expr_arg));
+                let ok_wrapped = make::expr_call(
+                    make::expr_path(make::path_unqualified(make::path_segment(make::name_ref(
+                        "Ok",
+                    )))),
+                    make::arg_list(iter::once(ret_expr_arg.clone())),
+                );
+                builder.replace_ast(ret_expr_arg, ok_wrapped);
             }
 
             match ctx.config.snippet_cap {
@@ -60,7 +68,7 @@ pub(crate) fn change_return_type_to_result(acc: &mut Assists, ctx: &AssistContex
 }
 
 struct TailReturnCollector {
-    exprs_to_wrap: Vec<SyntaxNode>,
+    exprs_to_wrap: Vec<ast::Expr>,
 }
 
 impl TailReturnCollector {
@@ -86,7 +94,8 @@ impl TailReturnCollector {
             if let Some(last_exprs) = get_tail_expr_from_block(&expr) {
                 for last_expr in last_exprs {
                     let last_expr = match last_expr {
-                        NodeType::Node(expr) | NodeType::Leaf(expr) => expr,
+                        NodeType::Node(expr) => expr,
+                        NodeType::Leaf(expr) => expr.syntax().clone(),
                     };
 
                     if let Some(last_expr) = Expr::cast(last_expr.clone()) {
@@ -113,12 +122,12 @@ impl TailReturnCollector {
             }
             Expr::ReturnExpr(ret_expr) => {
                 if let Some(ret_expr_arg) = &ret_expr.expr() {
-                    self.exprs_to_wrap.push(ret_expr_arg.syntax().clone());
+                    self.exprs_to_wrap.push(ret_expr_arg.clone());
                 }
             }
             Expr::BreakExpr(break_expr) if collect_break => {
                 if let Some(break_expr_arg) = &break_expr.expr() {
-                    self.exprs_to_wrap.push(break_expr_arg.syntax().clone());
+                    self.exprs_to_wrap.push(break_expr_arg.clone());
                 }
             }
             Expr::IfExpr(if_expr) => {
@@ -166,14 +175,11 @@ impl TailReturnCollector {
                     NodeType::Leaf(expr) => {
                         self.exprs_to_wrap.push(expr.clone());
                     }
-                    NodeType::Node(expr) => match &Expr::cast(expr.clone()) {
-                        Some(last_expr) => {
-                            self.fetch_tail_exprs(last_expr);
-                        }
-                        None => {
-                            self.exprs_to_wrap.push(expr.clone());
+                    NodeType::Node(expr) => {
+                        if let Some(last_expr) = Expr::cast(expr.clone()) {
+                            self.fetch_tail_exprs(&last_expr);
                         }
-                    },
+                    }
                 }
             }
         }
@@ -182,7 +188,7 @@ impl TailReturnCollector {
 
 #[derive(Debug)]
 enum NodeType {
-    Leaf(SyntaxNode),
+    Leaf(ast::Expr),
     Node(SyntaxNode),
 }
 
@@ -233,25 +239,26 @@ fn get_tail_expr_from_block(expr: &Expr) -> Option<Vec<NodeType>> {
 
             Some(arms)
         }
-        Expr::BreakExpr(expr) => expr.expr().map(|e| vec![NodeType::Leaf(e.syntax().clone())]),
+        Expr::BreakExpr(expr) => expr.expr().map(|e| vec![NodeType::Leaf(e)]),
         Expr::ReturnExpr(ret_expr) => Some(vec![NodeType::Node(ret_expr.syntax().clone())]),
-        Expr::CallExpr(call_expr) => Some(vec![NodeType::Leaf(call_expr.syntax().clone())]),
-        Expr::Literal(lit_expr) => Some(vec![NodeType::Leaf(lit_expr.syntax().clone())]),
-        Expr::TupleExpr(expr) => Some(vec![NodeType::Leaf(expr.syntax().clone())]),
-        Expr::ArrayExpr(expr) => Some(vec![NodeType::Leaf(expr.syntax().clone())]),
-        Expr::ParenExpr(expr) => Some(vec![NodeType::Leaf(expr.syntax().clone())]),
-        Expr::PathExpr(expr) => Some(vec![NodeType::Leaf(expr.syntax().clone())]),
-        Expr::RecordExpr(expr) => Some(vec![NodeType::Leaf(expr.syntax().clone())]),
-        Expr::IndexExpr(expr) => Some(vec![NodeType::Leaf(expr.syntax().clone())]),
-        Expr::MethodCallExpr(expr) => Some(vec![NodeType::Leaf(expr.syntax().clone())]),
-        Expr::AwaitExpr(expr) => Some(vec![NodeType::Leaf(expr.syntax().clone())]),
-        Expr::CastExpr(expr) => Some(vec![NodeType::Leaf(expr.syntax().clone())]),
-        Expr::RefExpr(expr) => Some(vec![NodeType::Leaf(expr.syntax().clone())]),
-        Expr::PrefixExpr(expr) => Some(vec![NodeType::Leaf(expr.syntax().clone())]),
-        Expr::RangeExpr(expr) => Some(vec![NodeType::Leaf(expr.syntax().clone())]),
-        Expr::BinExpr(expr) => Some(vec![NodeType::Leaf(expr.syntax().clone())]),
-        Expr::MacroCall(expr) => Some(vec![NodeType::Leaf(expr.syntax().clone())]),
-        Expr::BoxExpr(expr) => Some(vec![NodeType::Leaf(expr.syntax().clone())]),
+
+        Expr::CallExpr(_)
+        | Expr::Literal(_)
+        | Expr::TupleExpr(_)
+        | Expr::ArrayExpr(_)
+        | Expr::ParenExpr(_)
+        | Expr::PathExpr(_)
+        | Expr::RecordExpr(_)
+        | Expr::IndexExpr(_)
+        | Expr::MethodCallExpr(_)
+        | Expr::AwaitExpr(_)
+        | Expr::CastExpr(_)
+        | Expr::RefExpr(_)
+        | Expr::PrefixExpr(_)
+        | Expr::RangeExpr(_)
+        | Expr::BinExpr(_)
+        | Expr::MacroCall(_)
+        | Expr::BoxExpr(_) => Some(vec![NodeType::Leaf(expr.clone())]),
         _ => None,
     }
 }
diff --git a/crates/ra_assists/src/handlers/extract_struct_from_enum_variant.rs b/crates/ra_assists/src/handlers/extract_struct_from_enum_variant.rs
index 6e9f2d0fc..497f887cd 100644
--- a/crates/ra_assists/src/handlers/extract_struct_from_enum_variant.rs
+++ b/crates/ra_assists/src/handlers/extract_struct_from_enum_variant.rs
@@ -1,12 +1,11 @@
 use hir::{EnumVariant, Module, ModuleDef, Name};
 use ra_db::FileId;
-use ra_fmt::leading_indent;
 use ra_ide_db::{defs::Definition, search::Reference, RootDatabase};
 use rustc_hash::FxHashSet;
 use syntax::{
     algo::find_node_at_offset,
-    ast::{self, ArgListOwner, AstNode, NameOwner, VisibilityOwner},
-    SourceFile, SyntaxNode, TextRange, TextSize,
+    ast::{self, edit::IndentLevel, ArgListOwner, AstNode, NameOwner, VisibilityOwner},
+    SourceFile, TextRange, TextSize,
 };
 
 use crate::{
@@ -72,7 +71,7 @@ pub(crate) fn extract_struct_from_enum_variant(
             }
             extract_struct_def(
                 builder,
-                enum_ast.syntax(),
+                &enum_ast,
                 &variant_name,
                 &field_list.to_string(),
                 start_offset,
@@ -112,9 +111,10 @@ fn insert_import(
     Some(())
 }
 
+// FIXME: this should use strongly-typed `make`, rather than string manipulation.
 fn extract_struct_def(
     builder: &mut AssistBuilder,
-    enum_ast: &SyntaxNode,
+    enum_: &ast::Enum,
     variant_name: &str,
     variant_list: &str,
     start_offset: TextSize,
@@ -126,11 +126,7 @@ fn extract_struct_def(
     } else {
         "".to_string()
     };
-    let indent = if let Some(indent) = leading_indent(enum_ast) {
-        indent.to_string()
-    } else {
-        "".to_string()
-    };
+    let indent = IndentLevel::from_node(enum_.syntax());
     let struct_def = format!(
         r#"{}struct {}{};
 
diff --git a/crates/ra_assists/src/handlers/move_guard.rs b/crates/ra_assists/src/handlers/move_guard.rs
index c62ebc306..452115fe6 100644
--- a/crates/ra_assists/src/handlers/move_guard.rs
+++ b/crates/ra_assists/src/handlers/move_guard.rs
@@ -1,5 +1,5 @@
 use syntax::{
-    ast::{AstNode, IfExpr, MatchArm},
+    ast::{edit::AstNodeEdit, make, AstNode, IfExpr, MatchArm},
     SyntaxKind::WHITESPACE,
 };
 
@@ -25,7 +25,9 @@ use crate::{AssistContext, AssistId, AssistKind, Assists};
 //
 // fn handle(action: Action) {
 //     match action {
-//         Action::Move { distance } => if distance > 10 { foo() },
+//         Action::Move { distance } => if distance > 10 {
+//             foo()
+//         },
 //         _ => (),
 //     }
 // }
@@ -35,9 +37,13 @@ pub(crate) fn move_guard_to_arm_body(acc: &mut Assists, ctx: &AssistContext) ->
     let guard = match_arm.guard()?;
     let space_before_guard = guard.syntax().prev_sibling_or_token();
 
-    let guard_conditions = guard.expr()?;
+    let guard_condition = guard.expr()?;
     let arm_expr = match_arm.expr()?;
-    let buf = format!("if {} {{ {} }}", guard_conditions.syntax().text(), arm_expr.syntax().text());
+    let if_expr = make::expr_if(
+        make::condition(guard_condition, None),
+        make::block_expr(None, Some(arm_expr.clone())),
+    )
+    .indent(arm_expr.indent_level());
 
     let target = guard.syntax().text_range();
     acc.add(
@@ -53,7 +59,7 @@ pub(crate) fn move_guard_to_arm_body(acc: &mut Assists, ctx: &AssistContext) ->
             };
 
             edit.delete(guard.syntax().text_range());
-            edit.replace_node_and_indent(arm_expr.syntax(), buf);
+            edit.replace_ast(arm_expr, if_expr);
         },
     )
 }
@@ -134,16 +140,14 @@ mod tests {
         check_assist_target(
             move_guard_to_arm_body,
             r#"
-            fn f() {
-                let t = 'a';
-                let chars = "abcd";
-                match t {
-                    '\r' <|>if chars.clone().next() == Some('\n') => false,
-                    _ => true
-                }
-            }
-            "#,
-            r#"if chars.clone().next() == Some('\n')"#,
+fn main() {
+    match 92 {
+        x <|>if x > 10 => false,
+        _ => true
+    }
+}
+"#,
+            r#"if x > 10"#,
         );
     }
 
@@ -152,25 +156,23 @@ mod tests {
         check_assist(
             move_guard_to_arm_body,
             r#"
-            fn f() {
-                let t = 'a';
-                let chars = "abcd";
-                match t {
-                    '\r' <|>if chars.clone().next() == Some('\n') => false,
-                    _ => true
-                }
-            }
-            "#,
+fn main() {
+    match 92 {
+        x <|>if x > 10 => false,
+        _ => true
+    }
+}
+"#,
             r#"
-            fn f() {
-                let t = 'a';
-                let chars = "abcd";
-                match t {
-                    '\r' => if chars.clone().next() == Some('\n') { false },
-                    _ => true
-                }
-            }
-            "#,
+fn main() {
+    match 92 {
+        x => if x > 10 {
+            false
+        },
+        _ => true
+    }
+}
+"#,
         );
     }
 
@@ -179,21 +181,23 @@ mod tests {
         check_assist(
             move_guard_to_arm_body,
             r#"
-            fn f() {
-                match x {
-                    <|>y @ 4 | y @ 5    if y > 5 => true,
-                    _ => false
-                }
-            }
-            "#,
+fn main() {
+    match 92 {
+        <|>x @ 4 | x @ 5    if x > 5 => true,
+        _ => false
+    }
+}
+"#,
             r#"
-            fn f() {
-                match x {
-                    y @ 4 | y @ 5 => if y > 5 { true },
-                    _ => false
-                }
-            }
-            "#,
+fn main() {
+    match 92 {
+        x @ 4 | x @ 5 => if x > 5 {
+            true
+        },
+        _ => false
+    }
+}
+"#,
         );
     }
 
@@ -202,25 +206,21 @@ mod tests {
         check_assist(
             move_arm_cond_to_match_guard,
             r#"
-            fn f() {
-                let t = 'a';
-                let chars = "abcd";
-                match t {
-                    '\r' => if chars.clone().next() == Some('\n') { <|>false },
-                    _ => true
-                }
-            }
-            "#,
+fn main() {
+    match 92 {
+        x => if x > 10 { <|>false },
+        _ => true
+    }
+}
+"#,
             r#"
-            fn f() {
-                let t = 'a';
-                let chars = "abcd";
-                match t {
-                    '\r' if chars.clone().next() == Some('\n') => false,
-                    _ => true
-                }
-            }
-            "#,
+fn main() {
+    match 92 {
+        x if x > 10 => false,
+        _ => true
+    }
+}
+"#,
         );
     }
 
@@ -229,15 +229,13 @@ mod tests {
         check_assist_not_applicable(
             move_arm_cond_to_match_guard,
             r#"
-            fn f() {
-                let t = 'a';
-                let chars = "abcd";
-                match t {
-                    '\r' => if let Some(_) = chars.clone().next() { <|>false },
-                    _ => true
-                }
-            }
-            "#,
+fn main() {
+    match 92 {
+        x => if let 62 = x { <|>false },
+        _ => true
+    }
+}
+"#,
         );
     }
 
@@ -246,25 +244,21 @@ mod tests {
         check_assist(
             move_arm_cond_to_match_guard,
             r#"
-            fn f() {
-                let t = 'a';
-                let chars = "abcd";
-                match t {
-                    '\r' => if chars.clone().next().is_some() { <|> },
-                    _ => true
-                }
-            }
-            "#,
+fn main() {
+    match 92 {
+        x => if x > 10 { <|> },
+        _ => true
+    }
+}
+"#,
             r#"
-            fn f() {
-                let t = 'a';
-                let chars = "abcd";
-                match t {
-                    '\r' if chars.clone().next().is_some() => {  },
-                    _ => true
-                }
-            }
-            "#,
+fn main() {
+    match 92 {
+        x if x > 10 => {  },
+        _ => true
+    }
+}
+"#,
         );
     }
 
@@ -273,31 +267,27 @@ mod tests {
         check_assist(
             move_arm_cond_to_match_guard,
             r#"
-            fn f() {
-                let mut t = 'a';
-                let chars = "abcd";
-                match t {
-                    '\r' => if chars.clone().next().is_some() {
-                        t = 'e';<|>
-                        false
-                    },
-                    _ => true
-                }
-            }
-            "#,
+fn main() {
+    match 92 {
+        x => if x > 10 {
+            92;<|>
+            false
+        },
+        _ => true
+    }
+}
+"#,
             r#"
-            fn f() {
-                let mut t = 'a';
-                let chars = "abcd";
-                match t {
-                    '\r' if chars.clone().next().is_some() => {
-                        t = 'e';
-                        false
-                    },
-                    _ => true
-                }
-            }
-            "#,
+fn main() {
+    match 92 {
+        x if x > 10 => {
+            92;
+            false
+        },
+        _ => true
+    }
+}
+"#,
         );
     }
 }
diff --git a/crates/ra_assists/src/handlers/replace_if_let_with_match.rs b/crates/ra_assists/src/handlers/replace_if_let_with_match.rs
index 2442f049b..79097621e 100644
--- a/crates/ra_assists/src/handlers/replace_if_let_with_match.rs
+++ b/crates/ra_assists/src/handlers/replace_if_let_with_match.rs
@@ -1,4 +1,3 @@
-use ra_fmt::unwrap_trivial_block;
 use syntax::{
     ast::{
         self,
@@ -8,7 +7,10 @@ use syntax::{
     AstNode,
 };
 
-use crate::{utils::TryEnum, AssistContext, AssistId, AssistKind, Assists};
+use crate::{
+    utils::{unwrap_trivial_block, TryEnum},
+    AssistContext, AssistId, AssistKind, Assists,
+};
 
 // Assist: replace_if_let_with_match
 //
diff --git a/crates/ra_assists/src/handlers/unwrap_block.rs b/crates/ra_assists/src/handlers/unwrap_block.rs
index 2879090b8..3851aeb3e 100644
--- a/crates/ra_assists/src/handlers/unwrap_block.rs
+++ b/crates/ra_assists/src/handlers/unwrap_block.rs
@@ -1,4 +1,3 @@
-use ra_fmt::unwrap_trivial_block;
 use syntax::{
     ast::{
         self,
@@ -7,7 +6,7 @@ use syntax::{
     AstNode, TextRange, T,
 };
 
-use crate::{AssistContext, AssistId, AssistKind, Assists};
+use crate::{utils::unwrap_trivial_block, AssistContext, AssistId, AssistKind, Assists};
 
 // Assist: unwrap_block
 //