use crate::assist_context::{AssistContext, Assists}; use hir::HirDisplay; use ide_db::{ assists::{AssistId, AssistKind}, defs::NameRefClass, }; use syntax::{ ast::{self, edit::IndentLevel}, AstNode, }; // Assist: generate_constant // // Generate a named constant. // // ``` // struct S { i: usize } // impl S { pub fn new(n: usize) {} } // fn main() { // let v = S::new(CAPA$0CITY); // } // ``` // -> // ``` // struct S { i: usize } // impl S { pub fn new(n: usize) {} } // fn main() { // const CAPACITY: usize = $0; // let v = S::new(CAPACITY); // } // ``` pub(crate) fn generate_constant(acc: &mut Assists, ctx: &AssistContext) -> Option<()> { let constant_token = ctx.find_node_at_offset::<ast::NameRef>()?; let expr = constant_token.syntax().ancestors().find_map(ast::Expr::cast)?; let statement = expr.syntax().ancestors().find_map(ast::Stmt::cast)?; let ty = ctx.sema.type_of_expr(&expr)?; let scope = ctx.sema.scope(statement.syntax()); let module = scope.module()?; let type_name = ty.original().display_source_code(ctx.db(), module.into()).ok()?; let indent = IndentLevel::from_node(statement.syntax()); if !arg_list.syntax().text_range().contains_range(constant_token.syntax().text_range()) { return None; } if constant_token.to_string().chars().any(|it| !(it.is_uppercase() || it == '_')) { cov_mark::hit!(not_constant_name); return None; } if NameRefClass::classify(&ctx.sema, &constant_token).is_some() { cov_mark::hit!(already_defined); return None; } let target = statement.syntax().parent()?.text_range(); let statement_syntax = statement.syntax().clone_for_update(); acc.add( AssistId("generate_constant", AssistKind::QuickFix), "Generate constant", target, |builder| { builder.replace( statement.syntax().text_range(), format!( "const {}: {} = $0;\n{}{}", constant_token, type_name, indent, statement_syntax.text() ), ); }, ) } #[cfg(test)] mod tests { use super::*; use crate::tests::{check_assist, check_assist_not_applicable}; #[test] fn test_trivial() { check_assist( generate_constant, r#"struct S { i: usize } impl S { pub fn new(n: usize) {} } fn main() { let v = S::new(CAPA$0CITY); }"#, r#"struct S { i: usize } impl S { pub fn new(n: usize) {} } fn main() { const CAPACITY: usize = $0; let v = S::new(CAPACITY); }"#, ); } #[test] fn test_wont_apply_when_defined() { cov_mark::check!(already_defined); check_assist_not_applicable( generate_constant, r#"struct S { i: usize } impl S { pub fn new(n: usize) {} } fn main() { const CAPACITY: usize = 10; let v = S::new(CAPAC$0ITY); }"#, ); } #[test] fn test_wont_apply_when_maybe_not_constant() { cov_mark::check!(not_constant_name); check_assist_not_applicable( generate_constant, r#"struct S { i: usize } impl S { pub fn new(n: usize) {} } fn main() { let v = S::new(capa$0city); }"#, ); } }