Generate map assertion with error collection using duck typing Assumes map types have len() -> usize and get(&K) -> Option<&V> methods
(value_expr: &TokenStream, pattern: &PatternMap)
| 665 | /// Generate map assertion with error collection using duck typing |
| 666 | /// Assumes map types have len() -> usize and get(&K) -> Option<&V> methods |
| 667 | fn expand_map_assertion(value_expr: &TokenStream, pattern: &PatternMap) -> TokenStream { |
| 668 | let entries = &pattern.entries; |
| 669 | let rest = pattern.rest; |
| 670 | |
| 671 | // Use span from first entry or default span if empty |
| 672 | let map_span = entries |
| 673 | .first() |
| 674 | .map(|(key, _)| key.span()) |
| 675 | .unwrap_or_else(proc_macro2::Span::call_site); |
| 676 | |
| 677 | // Generate length check assertion for exact matching (when no rest pattern) |
| 678 | let len_check = if !rest { |
| 679 | let expected_len = entries.len(); |
| 680 | let error_push = generate_error_push( |
| 681 | map_span, |
| 682 | quote!(format!("map with {} entries", (#value_expr).len())), |
| 683 | quote!(Some(format!("{} entries", #expected_len))), |
| 684 | pattern.node_id, |
| 685 | ); |
| 686 | quote_spanned! {map_span=> |
| 687 | // Check exact length for maps without rest pattern |
| 688 | if (#value_expr).len() != #expected_len { |
| 689 | #error_push |
| 690 | } |
| 691 | } |
| 692 | } else { |
| 693 | quote! {} |
| 694 | }; |
| 695 | |
| 696 | // Generate key-value assertions |
| 697 | let key_value_assertions: Vec<TokenStream> = entries |
| 698 | .iter() |
| 699 | .map(|(key, value_pattern)| { |
| 700 | let key_str = quote! { #key }.to_string(); |
| 701 | |
| 702 | let span = key.span(); |
| 703 | let pattern_assertion = |
| 704 | expand_pattern_assertion("e! { __map_value }, value_pattern); |
| 705 | |
| 706 | let missing_key_error = generate_error_push( |
| 707 | span, |
| 708 | quote!("missing key".to_string()), |
| 709 | quote!(Some(format!("key present: {}", #key_str))), |
| 710 | pattern.node_id, |
| 711 | ); |
| 712 | |
| 713 | // Handle different key types for duck typing |
| 714 | let get_expr = if matches!( |
| 715 | key, |
| 716 | syn::Expr::Lit(syn::ExprLit { |
| 717 | lit: syn::Lit::Str(_), |
| 718 | .. |
| 719 | }) |
| 720 | ) { |
| 721 | // For string literals, convert to String to match HashMap<String, V> |
| 722 | quote_spanned! {span=> (#value_expr).get(&(#key).to_string()) } |
| 723 | } else { |
| 724 | // For other expressions, try as-is |
no test coverage detected