@newtype on array/map wrappers (#237)

* @newtype on array/map wrappers

Previously this only worked on primitive wrappers.

Now you can do e.g. `foo = [* uint] ; @newtype` which was ignored
before.

* cargo fmt

* tests added

src/intermediate.rs

@@ -90,6 +90,21 @@ impl AliasInfo {
     }
 }
 
+#[derive(Debug, Clone)]
+pub struct PlainGroupInfo<'a> {
+    group: Option<cddl::ast::Group<'a>>,
+    rule_metadata: RuleMetadata,
+}
+
+impl<'a> PlainGroupInfo<'a> {
+    pub fn new(group: Option<cddl::ast::Group<'a>>, rule_metadata: RuleMetadata) -> Self {
+        Self {
+            group,
+            rule_metadata,
+        }
+    }
+}
+
 #[derive(Debug)]
 pub struct IntermediateTypes<'a> {
     // Storing the cddl::Group is the easiest way to go here even after the parse/codegen split.
@@ -99,7 +114,7 @@ pub struct IntermediateTypes<'a> {
     // delayed until the point where it is referenced via self.set_rep_if_plain_group(rep)
     // Some(group) = directly defined in .cddl (must call set_plain_group_representatio() later)
     // None = indirectly generated due to a group choice (no reason to call set_rep_if_plain_group() later but it won't crash)
-    plain_groups: BTreeMap<RustIdent, Option<cddl::ast::Group<'a>>>,
+    plain_groups: BTreeMap<RustIdent, PlainGroupInfo<'a>>,
     type_aliases: BTreeMap<AliasIdent, AliasInfo>,
     rust_structs: BTreeMap<RustIdent, RustStruct>,
     prelude_to_emit: BTreeSet<String>,
@@ -642,8 +657,8 @@ impl<'a> IntermediateTypes<'a> {
     }
 
     // see self.plain_groups comments
-    pub fn mark_plain_group(&mut self, ident: RustIdent, group: Option<cddl::ast::Group<'a>>) {
-        self.plain_groups.insert(ident, group);
+    pub fn mark_plain_group(&mut self, ident: RustIdent, group_info: PlainGroupInfo<'a>) {
+        self.plain_groups.insert(ident, group_info);
     }
 
     // see self.plain_groups comments
@@ -656,7 +671,8 @@ impl<'a> IntermediateTypes<'a> {
     ) {
         if let Some(plain_group) = self.plain_groups.get(ident) {
             // the clone is to get around the borrow checker
-            if let Some(group) = plain_group.as_ref().cloned() {
+            let plain_group = plain_group.clone();
+            if let Some(group) = plain_group.group.as_ref() {
                 // we are defined via .cddl and thus need to register a concrete
                 // representation of the plain group
                 if let Some(rust_struct) = self.rust_structs.get(ident) {
@@ -673,11 +689,12 @@ impl<'a> IntermediateTypes<'a> {
                     crate::parsing::parse_group(
                         self,
                         parent_visitor,
-                        &group,
+                        group,
                         ident,
                         rep,
                         None,
                         None,
+                        &plain_group.rule_metadata,
                         cli,
                     );
                 }

src/main.rs

@@ -9,8 +9,9 @@ pub(crate) mod utils;
 
 use clap::Parser;
 use cli::Cli;
+use comment_ast::RuleMetadata;
 use generation::GenerationScope;
-use intermediate::{CDDLIdent, IntermediateTypes, RustIdent};
+use intermediate::{CDDLIdent, IntermediateTypes, PlainGroupInfo, RustIdent};
 use once_cell::sync::Lazy;
 use parsing::{parse_rule, rule_ident, rule_is_scope_marker};
 
@@ -128,10 +129,16 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
         if let cddl::ast::Rule::Group { rule, .. } = cddl_rule {
             // Freely defined group - no need to generate anything outside of group module
             match &rule.entry {
-                cddl::ast::GroupEntry::InlineGroup { group, .. } => {
+                cddl::ast::GroupEntry::InlineGroup {
+                    group,
+                    comments_after_group,
+                    ..
+                } => {
+                    assert_eq!(group.group_choices.len(), 1);
+                    let rule_metadata = RuleMetadata::from(comments_after_group.as_ref());
                     types.mark_plain_group(
                         RustIdent::new(CDDLIdent::new(rule.name.to_string())),
-                        Some(group.clone()),
+                        PlainGroupInfo::new(Some(group.clone()), rule_metadata),
                     );
                 }
                 x => panic!("Group rule with non-inline group? {:?}", x),

src/parsing.rs

@@ -6,8 +6,9 @@ use std::collections::BTreeMap;
 use crate::comment_ast::{merge_metadata, metadata_from_comments, RuleMetadata};
 use crate::intermediate::{
     AliasInfo, CBOREncodingOperation, CDDLIdent, ConceptualRustType, EnumVariant, FixedValue,
-    GenericDef, GenericInstance, IntermediateTypes, ModuleScope, Primitive, Representation,
-    RustField, RustIdent, RustRecord, RustStruct, RustStructType, RustType, VariantIdent,
+    GenericDef, GenericInstance, IntermediateTypes, ModuleScope, PlainGroupInfo, Primitive,
+    Representation, RustField, RustIdent, RustRecord, RustStruct, RustStructType, RustType,
+    VariantIdent,
 };
 use crate::utils::{
     append_number_if_duplicate, convert_to_camel_case, convert_to_snake_case,
@@ -640,6 +641,7 @@ fn parse_type(
                 Representation::Map,
                 outer_tag,
                 generic_params,
+                &rule_metadata,
                 cli,
             );
         }
@@ -654,6 +656,7 @@ fn parse_type(
                 Representation::Array,
                 outer_tag,
                 generic_params,
+                &rule_metadata,
                 cli,
             );
         }
@@ -1222,6 +1225,7 @@ fn rust_type_from_type2(
                                 Representation::Array,
                                 None,
                                 None,
+                                &rule_metadata,
                                 cli,
                             );
                             // we aren't returning an array, but rather a struct where the fields are ordered
@@ -1446,27 +1450,59 @@ fn parse_group_choice(
     rep: Representation,
     tag: Option<usize>,
     generic_params: Option<Vec<RustIdent>>,
+    parent_rule_metadata: Option<&RuleMetadata>,
     cli: &Cli,
 ) {
     let rule_metadata = RuleMetadata::from(
         get_comment_after(parent_visitor, &CDDLType::from(group_choice), None).as_ref(),
     );
+    let rule_metadata = if let Some(parent_rule_metadata) = parent_rule_metadata {
+        merge_metadata(&rule_metadata, parent_rule_metadata)
+    } else {
+        rule_metadata
+    };
     let rust_struct = match parse_group_type(types, parent_visitor, group_choice, rep, cli) {
         GroupParsingType::HomogenousArray(element_type) => {
-            // Array - homogeneous element type with proper occurence operator
-            RustStruct::new_array(name.clone(), tag, Some(&rule_metadata), element_type)
+            if rule_metadata.is_newtype {
+                // generate newtype over array
+                RustStruct::new_wrapper(
+                    name.clone(),
+                    tag,
+                    Some(&rule_metadata),
+                    ConceptualRustType::Array(Box::new(element_type)).into(),
+                    None,
+                )
+            } else {
+                // Array - homogeneous element type with proper occurence operator
+                RustStruct::new_array(name.clone(), tag, Some(&rule_metadata), element_type)
+            }
         }
         GroupParsingType::HomogenousMap(key_type, value_type) => {
-            // Table map - homogeneous key/value types
-            RustStruct::new_table(
-                name.clone(),
-                tag,
-                Some(&rule_metadata),
-                key_type,
-                value_type,
-            )
+            if rule_metadata.is_newtype {
+                // generate newtype over map
+                RustStruct::new_wrapper(
+                    name.clone(),
+                    tag,
+                    Some(&rule_metadata),
+                    ConceptualRustType::Map(Box::new(key_type), Box::new(value_type)).into(),
+                    None,
+                )
+            } else {
+                // Table map - homogeneous key/value types
+                RustStruct::new_table(
+                    name.clone(),
+                    tag,
+                    Some(&rule_metadata),
+                    key_type,
+                    value_type,
+                )
+            }
         }
         GroupParsingType::Heterogenous | GroupParsingType::WrappedBasicGroup(_) => {
+            assert!(
+                !rule_metadata.is_newtype,
+                "Can only use @newtype on primtives + heterogenious arrays/maps"
+            );
             // Heterogenous map or array with defined key/value pairs in the cddl like a struct
             let record =
                 parse_record_from_group_choice(types, rep, parent_visitor, group_choice, cli);
@@ -1489,6 +1525,7 @@ pub fn parse_group(
     rep: Representation,
     tag: Option<usize>,
     generic_params: Option<Vec<RustIdent>>,
+    parent_rule_metadata: &RuleMetadata,
     cli: &Cli,
 ) {
     if group.group_choices.len() == 1 {
@@ -1501,12 +1538,14 @@ pub fn parse_group(
             rep,
             tag,
             generic_params,
+            Some(parent_rule_metadata),
             cli,
         );
     } else {
         if generic_params.is_some() {
             todo!("{}: generic group choices not supported", name);
         }
+        assert!(!parent_rule_metadata.is_newtype);
         // Generate Enum object that is not exposed to wasm, since wasm can't expose
         // fully featured rust enums via wasm_bindgen
 
@@ -1570,7 +1609,10 @@ pub fn parse_group(
                     let ident_name = rule_metadata.name.unwrap_or_else(|| format!("{name}{i}"));
                     // General case, GroupN type identifiers and generate group choice since it's inlined here
                     let variant_name = RustIdent::new(CDDLIdent::new(ident_name));
-                    types.mark_plain_group(variant_name.clone(), None);
+                    types.mark_plain_group(
+                        variant_name.clone(),
+                        PlainGroupInfo::new(None, RuleMetadata::default()),
+                    );
                     parse_group_choice(
                         types,
                         parent_visitor,
@@ -1579,6 +1621,7 @@ pub fn parse_group(
                         rep,
                         None,
                         generic_params.clone(),
+                        None,
                         cli,
                     );
                     let name = VariantIdent::new_rust(variant_name.clone());

tests/core/input.cddl

@@ -185,6 +185,9 @@ inline_wrapper = [{ * text => text }]
 top_level_array = [* uint]
 top_level_single_elem = [uint]
 
+wrapper_table = { * uint => uint } ; @newtype
+wrapper_list = [ * uint ] ; @newtype
+
 overlapping_inlined = [
 	; @name one
 	0 //

tests/core/tests.rs

@@ -531,4 +531,35 @@ mod tests {
         ].into_iter().flatten().clone().collect::<Vec<u8>>();
         assert_eq!(expected_bytes, struct_with_custom_bytes.to_cbor_bytes());
     }
+
+    #[test]
+    fn wrapper_table() {
+        use cbor_event::Sz;
+        let bytes = vec![
+            map_sz(3, Sz::Inline),
+                cbor_int(5, Sz::Inline),
+                    cbor_int(4, Sz::Inline),
+                cbor_int(3, Sz::Inline),
+                    cbor_int(2, Sz::Inline),
+                cbor_int(1, Sz::Inline),
+                    cbor_int(0, Sz::Inline),
+        ].into_iter().flatten().clone().collect::<Vec<u8>>();
+        let from_bytes = WrapperTable::from_cbor_bytes(&bytes).unwrap();
+        deser_test(&from_bytes);
+    }
+
+    #[test]
+    fn wrapper_list() {
+        use cbor_event::Sz;
+        let bytes = vec![
+            arr_sz(5, Sz::Inline),
+                cbor_int(5, Sz::Inline),
+                cbor_int(4, Sz::Inline),
+                cbor_int(3, Sz::Inline),
+                cbor_int(2, Sz::Inline),
+                cbor_int(1, Sz::Inline),
+        ].into_iter().flatten().clone().collect::<Vec<u8>>();
+        let from_bytes = WrapperList::from_cbor_bytes(&bytes).unwrap();
+        deser_test(&from_bytes);
+    }
 }

tests/preserve-encodings/input.cddl

@@ -211,3 +211,6 @@ struct_with_custom_serialization = [
   tagged1: #6.9(custom_bytes),
   tagged2: #6.9(uint), ; @custom_serialize write_tagged_uint_str @custom_deserialize read_tagged_uint_str 
 ]
+
+wrapper_table = { * uint => uint } ; @newtype
+wrapper_list = [ * uint ] ; @newtype

tests/preserve-encodings/tests.rs

@@ -1264,4 +1264,39 @@ mod tests {
             }
         }
     }
+
+    #[test]
+    fn wrapper_table() {
+        let def_encodings = vec![Sz::Inline, Sz::One, Sz::Two, Sz::Four, Sz::Eight];
+        for def_enc in &def_encodings {
+            let irregular_bytes = vec![
+                map_sz(3, *def_enc),
+                    cbor_int(5, *def_enc),
+                        cbor_int(4, *def_enc),
+                    cbor_int(3, *def_enc),
+                        cbor_int(2, *def_enc),
+                    cbor_int(1, *def_enc),
+                        cbor_int(0, *def_enc),
+            ].into_iter().flatten().clone().collect::<Vec<u8>>();
+            let from_bytes = WrapperTable::from_cbor_bytes(&irregular_bytes).unwrap();
+            assert_eq!(from_bytes.to_cbor_bytes(), irregular_bytes);
+        }
+    }
+
+    #[test]
+    fn wrapper_list() {
+        let def_encodings = vec![Sz::Inline, Sz::One, Sz::Two, Sz::Four, Sz::Eight];
+        for def_enc in &def_encodings {
+            let irregular_bytes = vec![
+                arr_sz(5, *def_enc),
+                    cbor_int(5, *def_enc),
+                    cbor_int(4, *def_enc),
+                    cbor_int(3, *def_enc),
+                    cbor_int(2, *def_enc),
+                    cbor_int(1, *def_enc),
+            ].into_iter().flatten().clone().collect::<Vec<u8>>();
+            let from_bytes = WrapperList::from_cbor_bytes(&irregular_bytes).unwrap();
+            assert_eq!(from_bytes.to_cbor_bytes(), irregular_bytes);
+        }
+    }
 }