editoast: add ToToken ModelV2 definition ChangesetBuilderImplBlock

Author: leovalais

editoast/editoast_derive/src/modelv2.rs

@@ -31,8 +31,8 @@ pub fn model(input: &DeriveInput) -> Result<TokenStream> {
     let model_from_row_impl = config.model_from_row_impl();
     let changeset_from_model_impl = config.changeset_from_model_impl();
 
-    let cs_builder = config.make_builder(true);
-    let patch_builder = config.make_builder(false);
+    let changeset_builder = config.changeset_builder_impl_block();
+    let patch_builder = config.patch_builder_impl_block();
 
     let model_impls = config.make_model_traits_impl();
 
@@ -47,8 +47,9 @@ pub fn model(input: &DeriveInput) -> Result<TokenStream> {
         #model_from_row_impl
         #changeset_from_model_impl
 
-        #cs_builder
+        #changeset_builder
         #patch_builder
+
         #model_impls
     })
 }

editoast/editoast_derive/src/modelv2/codegen.rs

@@ -1,3 +1,4 @@
+mod changeset_builder_impl_block;
 mod changeset_decl;
 mod changeset_from_model;
 mod identifiable_impl;
@@ -8,14 +9,15 @@ mod row_decl;
 
 use proc_macro2::{Span, TokenStream};
 use quote::quote;
-use syn::parse_quote;
 
 use crate::modelv2::codegen::changeset_decl::ChangesetDecl;
 use crate::modelv2::codegen::changeset_decl::ChangesetFieldDecl;
 use crate::modelv2::codegen::model_impl::ModelImpl;
 use crate::modelv2::codegen::row_decl::RowDecl;
 use crate::modelv2::codegen::row_decl::RowFieldDecl;
 
+use self::changeset_builder_impl_block::BuilderType;
+use self::changeset_builder_impl_block::ChangesetBuilderImplBlock;
 use self::changeset_from_model::ChangesetFromModelImpl;
 use self::identifiable_impl::IdentifiableImpl;
 use self::model_from_row_impl::ModelFromRowImpl;
@@ -71,65 +73,26 @@ impl ModelConfig {
         }
     }
 
-    pub fn make_builder(&self, changeset: bool) -> TokenStream {
-        let np!(fields, fns, flat_fns, types, bodies, flat_bodies): np!(vec6) = self
-            .iter_fields()
-            .filter(|f| !self.is_primary(f))
-            .filter(|field| !field.builder_skip)
-            .map(|field| {
-                let ident = &field.ident;
-                let expr = field.into_transformed(parse_quote! { #ident });
-                let body = if changeset {
-                    quote! { self.#ident = Some(#expr) }
-                } else {
-                    quote! { self.changeset.#ident = Some(#expr) }
-                };
-                let flat_body = if changeset {
-                    quote! { self.#ident = #ident.map(|#ident| #expr) }
-                } else {
-                    quote! { self.changeset.#ident = #ident.map(|#ident| #expr) }
-                };
-                np!(
-                    ident,
-                    &field.builder_ident,
-                    syn::Ident::new(&format!("flat_{}", &field.builder_ident), Span::call_site()),
-                    &field.ty,
-                    body,
-                    flat_body
-                )
-            })
-            .unzip();
-
-        let impl_decl = if changeset {
-            let tn = self.changeset.ident();
-            quote! { impl #tn }
-        } else {
-            let tn = &self.model;
-            quote! { impl<'a> crate::modelsv2::Patch<'a, #tn> }
-        };
-
-        quote! {
-            #[automatically_derived]
-            #impl_decl {
-                #(
-                    #[allow(unused)]
-                    #[must_use = "builder methods are intended to be chained"]
-                    pub fn #fns(mut self, #fields: #types) -> Self {
-                        #bodies;
-                        self
-                    }
-
-                    #[allow(unused)]
-                    #[must_use = "builder methods are intended to be chained"]
-                    pub fn #flat_fns(mut self, #fields: Option<#types>) -> Self {
-                        #flat_bodies;
-                        self
-                    }
-                )*
-            }
+    pub(crate) fn changeset_builder_impl_block(&self) -> ChangesetBuilderImplBlock {
+        ChangesetBuilderImplBlock {
+            builder_type: BuilderType::Changeset,
+            model: self.model.clone(),
+            changeset: self.changeset.ident(),
+            fields: self
+                .iter_fields()
+                .filter(|field| !self.is_primary(field))
+                .filter(|field| !field.builder_skip)
+                .cloned()
+                .collect(),
         }
     }
 
+    pub(crate) fn patch_builder_impl_block(&self) -> ChangesetBuilderImplBlock {
+        let mut builder = self.changeset_builder_impl_block();
+        builder.builder_type = BuilderType::Patch;
+        builder
+    }
+
     pub(crate) fn identifiable_impls(&self) -> Vec<IdentifiableImpl> {
         self.identifiers
             .iter()

editoast/editoast_derive/src/modelv2/codegen/changeset_builder_impl_block.rs

@@ -0,0 +1,93 @@
+use proc_macro2::Span;
+use proc_macro2::TokenStream;
+use quote::quote;
+use quote::ToTokens;
+use syn::parse_quote;
+
+use crate::modelv2::ModelField;
+
+pub(super) enum BuilderType {
+    Changeset,
+    Patch,
+}
+
+pub(crate) struct ChangesetBuilderImplBlock {
+    pub(super) builder_type: BuilderType,
+    pub(super) model: syn::Ident,
+    pub(super) changeset: syn::Ident,
+    pub(super) fields: Vec<ModelField>,
+}
+
+impl ChangesetBuilderImplBlock {
+    fn impl_decl(&self) -> TokenStream {
+        let Self {
+            model, changeset, ..
+        } = self;
+        match self.builder_type {
+            BuilderType::Changeset => quote! { impl #changeset },
+            BuilderType::Patch => quote! {  impl<'a> crate::modelsv2::Patch<'a, #model> },
+        }
+    }
+
+    fn builder_field_fn_decl(&self, field: &ModelField) -> syn::ItemFn {
+        let ident = &field.ident;
+        let ty = &field.ty;
+        let value = field.into_transformed(parse_quote! { #ident });
+        let statement = match self.builder_type {
+            BuilderType::Changeset => quote! { self.#ident = Some(#value) },
+            BuilderType::Patch => quote! { self.changeset.#ident = Some(#value) },
+        };
+        parse_quote! {
+            pub fn #ident(mut self, #ident: #ty) -> Self {
+                #statement;
+                self
+            }
+        }
+    }
+
+    fn builder_flat_fn_decl(&self, field: &ModelField) -> syn::ItemFn {
+        let ident = &field.ident;
+        let ty = &field.ty;
+        let value = field.into_transformed(parse_quote! { #ident });
+        let statement = match self.builder_type {
+            BuilderType::Changeset => quote! { self.#ident = #ident.map(|#ident| #value) },
+            BuilderType::Patch => quote! { self.changeset.#ident = #ident.map(|#ident| #value) },
+        };
+        let name = syn::Ident::new(&format!("flat_{}", &field.builder_ident), Span::call_site());
+        parse_quote! {
+            pub fn #name(mut self, #ident: Option<#ty>) -> Self {
+                #statement;
+                self
+            }
+        }
+    }
+}
+
+impl ToTokens for ChangesetBuilderImplBlock {
+    fn to_tokens(&self, tokens: &mut proc_macro2::TokenStream) {
+        let impl_decl = self.impl_decl();
+        let field_fns = self
+            .fields
+            .iter()
+            .map(|field| self.builder_field_fn_decl(field));
+        let flat_fns = self
+            .fields
+            .iter()
+            .map(|field| self.builder_flat_fn_decl(field));
+        tokens.extend(quote! {
+            #[automatically_derived]
+            #impl_decl {
+                #(
+                    #[allow(unused)]
+                    #[must_use = "builder methods are intended to be chained"]
+                    #field_fns
+                )*
+                #(
+                    #[allow(unused)]
+                    #[must_use = "builder methods are intended to be chained"]
+                    #flat_fns
+                )*
+            }
+        });
+    }
+}