1 use crate::assist_context::{AssistContext, Assists};
4 assists::{AssistId, AssistKind},
8 ast::{self, edit::IndentLevel},
12 // Assist: generate_constant
14 // Generate a named constant.
17 // struct S { i: usize }
18 // impl S { pub fn new(n: usize) {} }
20 // let v = S::new(CAPA$0CITY);
25 // struct S { i: usize }
26 // impl S { pub fn new(n: usize) {} }
28 // const CAPACITY: usize = $0;
29 // let v = S::new(CAPACITY);
33 pub(crate) fn generate_constant(acc: &mut Assists, ctx: &AssistContext) -> Option<()> {
34 let constant_token = ctx.find_node_at_offset::<ast::NameRef>()?;
35 let expr = constant_token.syntax().ancestors().find_map(ast::Expr::cast)?;
36 let statement = expr.syntax().ancestors().find_map(ast::Stmt::cast)?;
37 let ty = ctx.sema.type_of_expr(&expr)?;
38 let scope = ctx.sema.scope(statement.syntax());
39 let module = scope.module()?;
40 let type_name = ty.original().display_source_code(ctx.db(), module.into()).ok()?;
41 let indent = IndentLevel::from_node(statement.syntax());
42 if constant_token.to_string().chars().any(|it| !(it.is_uppercase() || it == '_')) {
43 cov_mark::hit!(not_constant_name);
46 if NameRefClass::classify(&ctx.sema, &constant_token).is_some() {
47 cov_mark::hit!(already_defined);
50 let target = statement.syntax().parent()?.text_range();
52 AssistId("generate_constant", AssistKind::QuickFix),
57 statement.syntax().text_range().start(),
58 format!("const {}: {} = $0;\n{}", constant_token, type_name, indent),
67 use crate::tests::{check_assist, check_assist_not_applicable};
73 r#"struct S { i: usize }
75 pub fn new(n: usize) {}
78 let v = S::new(CAPA$0CITY);
80 r#"struct S { i: usize }
82 pub fn new(n: usize) {}
85 const CAPACITY: usize = $0;
86 let v = S::new(CAPACITY);
91 fn test_wont_apply_when_defined() {
92 cov_mark::check!(already_defined);
93 check_assist_not_applicable(
95 r#"struct S { i: usize }
97 pub fn new(n: usize) {}
100 const CAPACITY: usize = 10;
101 let v = S::new(CAPAC$0ITY);
106 fn test_wont_apply_when_maybe_not_constant() {
107 cov_mark::check!(not_constant_name);
108 check_assist_not_applicable(
110 r#"struct S { i: usize }
112 pub fn new(n: usize) {}
115 let v = S::new(capa$0city);