implement both owning and const generic field array writers

Author: burrbull

.github/bors.toml

@@ -15,7 +15,7 @@ status = [
   "ci-linux (stable, Spansion, x86_64-unknown-linux-gnu, linux)",
   "ci-linux (stable, STMicro, x86_64-unknown-linux-gnu, linux)",
   "ci-linux (stable, Toshiba, x86_64-unknown-linux-gnu, linux)",
-  "ci-linux (1.40.0, Nordic, x86_64-unknown-linux-gnu, linux)",
+  "ci-linux (1.51.0, Nordic, x86_64-unknown-linux-gnu, linux)",
   "ci-linux (stable, x86_64-apple-darwin, osx)",
   "ci-linux (stable, x86_64-pc-windows-msvc, windows)",
 ]

.github/workflows/ci.yml

@@ -25,7 +25,7 @@ jobs:
 
         include:
           # Test MSRV
-          - rust: 1.40.0
+          - rust: 1.51.0
             VENDOR: Nordic
             TARGET: x86_64-unknown-linux-gnu
             TRAVIS_OS_NAME: linux

CHANGELOG.md

@@ -30,6 +30,8 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 ### Changed
 
+- [breaking-change] support for "field arrays"
+
 - [breaking-change] remove `Variant<U, ENUM_A>`, use `Option<ENUM_A>` instead
 
 - split out register size type (`RawType`) from `ResetValue` trait

src/generate/register.rs

@@ -563,6 +563,7 @@ pub fn fields(
         if can_write {
             let new_pc_aw = Ident::new(&(name_pc.clone() + "_AW"), span);
             let name_pc_w = Ident::new(&(name_pc.clone() + "_W"), span);
+            let name_pc_cgw = Ident::new(&(name_pc.clone() + "_CGW"), span);
 
             let mut proxy_items = TokenStream::new();
             let mut unsafety = unsafety(f.write_constraint.as_ref(), width);
@@ -639,59 +640,97 @@ pub fn fields(
                 });
             }
 
-            proxy_items.extend(if field_dim.is_some() {
-                quote! {
+            let mut proxy_items_fa = TokenStream::new();
+            let mut proxy_items_cg = TokenStream::new();
+            if field_dim.is_some() {
+                proxy_items_fa.extend(quote! {
                     ///Writes raw bits to the field
                     #inline
                     pub #unsafety fn #bits(self, value: #fty) -> &'a mut W {
                         self.w.bits = (self.w.bits & !(#hexmask << self.offset)) | ((value as #rty & #hexmask) << self.offset);
                         self.w
                     }
-                }
-            } else if offset != 0 {
-                let offset = &util::unsuffixed(offset);
-                quote! {
+                });
+                proxy_items_cg.extend(quote! {
                     ///Writes raw bits to the field
                     #inline
                     pub #unsafety fn #bits(self, value: #fty) -> &'a mut W {
-                        self.w.bits = (self.w.bits & !(#hexmask << #offset)) | ((value as #rty & #hexmask) << #offset);
+                        self.w.bits = (self.w.bits & !(#hexmask << O)) | ((value as #rty & #hexmask) << O);
                         self.w
                     }
-                }
+                });
             } else {
-                quote! {
-                    ///Writes raw bits to the field
-                    #inline
-                    pub #unsafety fn #bits(self, value: #fty) -> &'a mut W {
-                        self.w.bits = (self.w.bits & !#hexmask) | (value as #rty & #hexmask);
-                        self.w
+                proxy_items.extend(if offset != 0 {
+                    let offset = &util::unsuffixed(offset);
+                    quote! {
+                        ///Writes raw bits to the field
+                        #inline
+                        pub #unsafety fn #bits(self, value: #fty) -> &'a mut W {
+                            self.w.bits = (self.w.bits & !(#hexmask << #offset)) | ((value as #rty & #hexmask) << #offset);
+                            self.w
+                        }
                     }
-                }
-            });
+                } else {
+                    quote! {
+                        ///Writes raw bits to the field
+                        #inline
+                        pub #unsafety fn #bits(self, value: #fty) -> &'a mut W {
+                            self.w.bits = (self.w.bits & !#hexmask) | (value as #rty & #hexmask);
+                            self.w
+                        }
+                    }
+                });
+            }
 
-            let doc;
-            let offset_entry;
-            if let Some((_, _, _, _, suffixes_str)) = &field_dim {
-                doc = format!(
-                    "Fields `{}` writer - {}",
+            let mut cgdoc = String::new();
+            let doc = if let Some((_, _, _, _, suffixes_str)) = &field_dim {
+                cgdoc = format!(
+                    "Fields `{}` const generic writer - {}",
                     util::replace_suffix(&f.name, suffixes_str),
                     description
                 );
-                offset_entry = quote! {offset: usize,};
+                format!(
+                    "Fields `{}` writer - {}",
+                    util::replace_suffix(&f.name, suffixes_str),
+                    description
+                )
             } else {
-                doc = format!("Field `{}` writer - {}", f.name, description);
-                offset_entry = quote! {};
-            }
+                format!("Field `{}` writer - {}", f.name, description)
+            };
+
+            mod_items.extend(if field_dim.is_some() {
+                quote! {
+                    #[doc = #doc]
+                    pub struct #name_pc_w<'a> {
+                        w: &'a mut W,
+                        offset: usize,
+                    }
+
+                    impl<'a> #name_pc_w<'a> {
+                        #proxy_items
+                        #proxy_items_fa
+                    }
 
-            mod_items.extend(quote! {
-                #[doc = #doc]
-                pub struct #name_pc_w<'a> {
-                    w: &'a mut W,
-                    #offset_entry
+                    #[doc = #cgdoc]
+                    pub struct #name_pc_cgw<'a, const O: usize> {
+                        w: &'a mut W,
+                    }
+
+                    impl<'a, const O: usize> #name_pc_cgw<'a, O> {
+                        #proxy_items
+                        #proxy_items_cg
+                    }
                 }
+            } else {
+                quote! {
+                    #[doc = #doc]
+                    pub struct #name_pc_w<'a> {
+                        w: &'a mut W,
+                    }
 
-                impl<'a> #name_pc_w<'a> {
-                    #proxy_items
+                    impl<'a> #name_pc_w<'a> {
+                        #proxy_items
+                    }
                 }
             });
 
@@ -719,8 +758,8 @@ pub fn fields(
                     w_impl_items.extend(quote! {
                         #[doc = #doc]
                         #inline
-                        pub fn #name_sc_n(&mut self) -> #name_pc_w {
-                            #name_pc_w { w: self, offset: #sub_offset }
+                        pub fn #name_sc_n(&mut self) -> #name_pc_cgw<#sub_offset> {
+                            #name_pc_cgw { w: self }
                         }
                     });
                 }