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-rw-r--r--crates/ra_assists/src/handlers/early_return.rs160
1 files changed, 83 insertions, 77 deletions
diff --git a/crates/ra_assists/src/handlers/early_return.rs b/crates/ra_assists/src/handlers/early_return.rs
index dfade7432..3650289fd 100644
--- a/crates/ra_assists/src/handlers/early_return.rs
+++ b/crates/ra_assists/src/handlers/early_return.rs
@@ -8,14 +8,14 @@ use ra_syntax::{
8 make, 8 make,
9 }, 9 },
10 AstNode, 10 AstNode,
11 SyntaxKind::{FN_DEF, LOOP_EXPR, L_CURLY, R_CURLY, WHILE_EXPR, WHITESPACE}, 11 SyntaxKind::{FN, LOOP_EXPR, L_CURLY, R_CURLY, WHILE_EXPR, WHITESPACE},
12 SyntaxNode, 12 SyntaxNode,
13}; 13};
14 14
15use crate::{ 15use crate::{
16 assist_context::{AssistContext, Assists}, 16 assist_context::{AssistContext, Assists},
17 utils::invert_boolean_expression, 17 utils::invert_boolean_expression,
18 AssistId, 18 AssistId, AssistKind,
19}; 19};
20 20
21// Assist: convert_to_guarded_return 21// Assist: convert_to_guarded_return
@@ -88,7 +88,7 @@ pub(crate) fn convert_to_guarded_return(acc: &mut Assists, ctx: &AssistContext)
88 88
89 let early_expression: ast::Expr = match parent_container.kind() { 89 let early_expression: ast::Expr = match parent_container.kind() {
90 WHILE_EXPR | LOOP_EXPR => make::expr_continue(), 90 WHILE_EXPR | LOOP_EXPR => make::expr_continue(),
91 FN_DEF => make::expr_return(), 91 FN => make::expr_return(),
92 _ => return None, 92 _ => return None,
93 }; 93 };
94 94
@@ -99,86 +99,92 @@ pub(crate) fn convert_to_guarded_return(acc: &mut Assists, ctx: &AssistContext)
99 then_block.syntax().last_child_or_token().filter(|t| t.kind() == R_CURLY)?; 99 then_block.syntax().last_child_or_token().filter(|t| t.kind() == R_CURLY)?;
100 100
101 let target = if_expr.syntax().text_range(); 101 let target = if_expr.syntax().text_range();
102 acc.add(AssistId("convert_to_guarded_return"), "Convert to guarded return", target, |edit| { 102 acc.add(
103 let if_indent_level = IndentLevel::from_node(&if_expr.syntax()); 103 AssistId("convert_to_guarded_return", AssistKind::RefactorRewrite),
104 let new_block = match if_let_pat { 104 "Convert to guarded return",
105 None => { 105 target,
106 // If. 106 |edit| {
107 let new_expr = { 107 let if_indent_level = IndentLevel::from_node(&if_expr.syntax());
108 let then_branch = 108 let new_block = match if_let_pat {
109 make::block_expr(once(make::expr_stmt(early_expression).into()), None); 109 None => {
110 let cond = invert_boolean_expression(cond_expr); 110 // If.
111 make::expr_if(make::condition(cond, None), then_branch).indent(if_indent_level) 111 let new_expr = {
112 }; 112 let then_branch =
113 replace(new_expr.syntax(), &then_block, &parent_block, &if_expr) 113 make::block_expr(once(make::expr_stmt(early_expression).into()), None);
114 } 114 let cond = invert_boolean_expression(cond_expr);
115 Some((path, bound_ident)) => { 115 make::expr_if(make::condition(cond, None), then_branch)
116 // If-let. 116 .indent(if_indent_level)
117 let match_expr = {
118 let happy_arm = {
119 let pat = make::tuple_struct_pat(
120 path,
121 once(make::bind_pat(make::name("it")).into()),
122 );
123 let expr = {
124 let name_ref = make::name_ref("it");
125 let segment = make::path_segment(name_ref);
126 let path = make::path_unqualified(segment);
127 make::expr_path(path)
128 };
129 make::match_arm(once(pat.into()), expr)
130 }; 117 };
118 replace(new_expr.syntax(), &then_block, &parent_block, &if_expr)
119 }
120 Some((path, bound_ident)) => {
121 // If-let.
122 let match_expr = {
123 let happy_arm = {
124 let pat = make::tuple_struct_pat(
125 path,
126 once(make::bind_pat(make::name("it")).into()),
127 );
128 let expr = {
129 let name_ref = make::name_ref("it");
130 let segment = make::path_segment(name_ref);
131 let path = make::path_unqualified(segment);
132 make::expr_path(path)
133 };
134 make::match_arm(once(pat.into()), expr)
135 };
131 136
132 let sad_arm = make::match_arm( 137 let sad_arm = make::match_arm(
133 // FIXME: would be cool to use `None` or `Err(_)` if appropriate 138 // FIXME: would be cool to use `None` or `Err(_)` if appropriate
134 once(make::placeholder_pat().into()), 139 once(make::placeholder_pat().into()),
135 early_expression, 140 early_expression,
136 ); 141 );
137 142
138 make::expr_match(cond_expr, make::match_arm_list(vec![happy_arm, sad_arm])) 143 make::expr_match(cond_expr, make::match_arm_list(vec![happy_arm, sad_arm]))
139 }; 144 };
140 145
141 let let_stmt = make::let_stmt( 146 let let_stmt = make::let_stmt(
142 make::bind_pat(make::name(&bound_ident.syntax().to_string())).into(), 147 make::bind_pat(make::name(&bound_ident.syntax().to_string())).into(),
143 Some(match_expr), 148 Some(match_expr),
149 );
150 let let_stmt = let_stmt.indent(if_indent_level);
151 replace(let_stmt.syntax(), &then_block, &parent_block, &if_expr)
152 }
153 };
154 edit.replace_ast(parent_block, ast::BlockExpr::cast(new_block).unwrap());
155
156 fn replace(
157 new_expr: &SyntaxNode,
158 then_block: &ast::BlockExpr,
159 parent_block: &ast::BlockExpr,
160 if_expr: &ast::IfExpr,
161 ) -> SyntaxNode {
162 let then_block_items = then_block.dedent(IndentLevel(1));
163 let end_of_then = then_block_items.syntax().last_child_or_token().unwrap();
164 let end_of_then =
165 if end_of_then.prev_sibling_or_token().map(|n| n.kind()) == Some(WHITESPACE) {
166 end_of_then.prev_sibling_or_token().unwrap()
167 } else {
168 end_of_then
169 };
170 let mut then_statements = new_expr.children_with_tokens().chain(
171 then_block_items
172 .syntax()
173 .children_with_tokens()
174 .skip(1)
175 .take_while(|i| *i != end_of_then),
144 ); 176 );
145 let let_stmt = let_stmt.indent(if_indent_level); 177 replace_children(
146 replace(let_stmt.syntax(), &then_block, &parent_block, &if_expr) 178 &parent_block.syntax(),
179 RangeInclusive::new(
180 if_expr.clone().syntax().clone().into(),
181 if_expr.syntax().clone().into(),
182 ),
183 &mut then_statements,
184 )
147 } 185 }
148 }; 186 },
149 edit.replace_ast(parent_block, ast::BlockExpr::cast(new_block).unwrap()); 187 )
150
151 fn replace(
152 new_expr: &SyntaxNode,
153 then_block: &ast::BlockExpr,
154 parent_block: &ast::BlockExpr,
155 if_expr: &ast::IfExpr,
156 ) -> SyntaxNode {
157 let then_block_items = then_block.dedent(IndentLevel(1));
158 let end_of_then = then_block_items.syntax().last_child_or_token().unwrap();
159 let end_of_then =
160 if end_of_then.prev_sibling_or_token().map(|n| n.kind()) == Some(WHITESPACE) {
161 end_of_then.prev_sibling_or_token().unwrap()
162 } else {
163 end_of_then
164 };
165 let mut then_statements = new_expr.children_with_tokens().chain(
166 then_block_items
167 .syntax()
168 .children_with_tokens()
169 .skip(1)
170 .take_while(|i| *i != end_of_then),
171 );
172 replace_children(
173 &parent_block.syntax(),
174 RangeInclusive::new(
175 if_expr.clone().syntax().clone().into(),
176 if_expr.syntax().clone().into(),
177 ),
178 &mut then_statements,
179 )
180 }
181 })
182} 188}
183 189
184#[cfg(test)] 190#[cfg(test)]
generated by cgit v1.2.3 (git 2.25.1) at 2024-09-13 21:52:10 +0100