src/tools/rust-analyzer/crates/ide-db/src/use_trivial_contructor.rs

   1 //! Functionality for generating trivial contructors
   2
   3 use hir::StructKind;
   4 use syntax::ast;
   5
   6 /// given a type return the trivial contructor (if one exists)
   7 pub fn use_trivial_constructor(
   8     db: &crate::RootDatabase,
   9     path: ast::Path,
  10     ty: &hir::Type,
  11 ) -> Option<ast::Expr> {
  12     match ty.as_adt() {
  13         Some(hir::Adt::Enum(x)) => {
  14             if let &[variant] = &*x.variants(db) {
  15                 if variant.kind(db) == hir::StructKind::Unit {
  16                     let path = ast::make::path_qualified(
  17                         path,
  18                         syntax::ast::make::path_segment(ast::make::name_ref(
  19                             &variant.name(db).to_smol_str(),
  20                         )),
  21                     );
  22
  23                     return Some(syntax::ast::make::expr_path(path));
  24                 }
  25             }
  26         }
  27         Some(hir::Adt::Struct(x)) if x.kind(db) == StructKind::Unit => {
  28             return Some(syntax::ast::make::expr_path(path));
  29         }
  30         _ => {}
  31     }
  32
  33     None
  34 }