Add a derive macro for setting fields

charming-derive/Cargo.toml

@@ -0,0 +1,16 @@
+[package]
+name = "charming-derive"
+version = "0.1.0"
+edition = "2021"
+
+[lib]
+proc-macro = true
+
+[dependencies]
+proc-macro2 = "1.0.87"
+quote = "1.0.37"
+syn = { version = "2.0.79", features = ["extra-traits", "visit", "derive"] }
+
+[dev-dependencies]
+charming = { path = "../charming" }
+serde = { version = "1.0", features = ["derive"] }

charming-derive/src/lib.rs

@@ -0,0 +1,236 @@
+#![cfg_attr(docsrs, feature(doc_cfg))]
+/*!
+CharmingSetter is a derive macro for the Charming chart rendering library. It is used to remove a lot of boilerplate code
+in the library by implementing common methods to set the fields of structs.
+
+Example without the macro
+```rust
+use serde::Serialize;
+use charming::component::Title;
+use charming::element::Tooltip;
+
+#[derive(Serialize, Debug, Clone)]
+struct Chart {
+    #[serde(skip_serializing_if = "Vec::is_empty")]
+    title: Vec<Title>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    tooltip: Option<Tooltip>,
+
+    // many fields cut for brevity
+}
+
+// For setting these fields with the setter pattern we would need to implement the following
+// methods manually when we are not using the derive macro
+impl Chart {
+    pub fn new() -> Self {
+        Self {
+            title: Vec::new(),
+            tooltip: None,
+        }
+    }
+    pub fn title<T: Into<Title>>(mut self, title: T) -> Self {
+        self.title.push(title.into());
+        self
+    }
+    pub fn tooltip<T: Into<Tooltip>>(mut self, tooltip: T) -> Self {
+        self.tooltip = Some(tooltip.into());
+        self
+    }
+
+    // many methods cut for brevity
+}
+
+// Example chart creation
+let chart = Chart::new().title(Title::new().text("Title")).tooltip(Tooltip::new());
+```
+
+Example with the macro
+```rust
+use serde::Serialize;
+use charming::component::Title;
+use charming::element::Tooltip;
+use charming_derive::CharmingSetter;
+
+#[derive(Serialize, Debug, Clone, CharmingSetter)]
+struct Chart {
+    #[serde(skip_serializing_if = "Vec::is_empty")]
+    title: Vec<Title>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    tooltip: Option<Tooltip>,
+
+    // many fields cut for brevity
+}
+// The setter methods from the example above now get implemented automatically by CharmingSetter
+
+// Example chart creation
+let chart = Chart::new().title(Title::new().text("Title")).tooltip(Tooltip::new());
+```
+
+Field attributes charming_type and charming_skip_setter
+```rust
+use serde::Serialize;
+use charming::datatype::DataPoint;
+use charming_derive::CharmingSetter;
+
+#[derive(Serialize, Debug, Clone, CharmingSetter)]
+#[serde(rename_all = "camelCase")]
+pub struct Line {
+    // charming_type gets used here to provide the value "line" as the default value for
+    // the field 'type_' when calling Line::new() and also removes the method to set the field
+    #[serde(rename = "type")]
+    #[charming_type = "line"]
+    type_: String,
+
+    // cut for brevity
+
+    // charming_skip_setter gets used here to remove the default implementation of the setter
+    // method for this field, a manual method to set this field needs to be provided instead
+    #[serde(skip_serializing_if = "Vec::is_empty")]
+    #[charming_skip_setter]
+    data: Vec<DataPoint>,
+}
+
+impl Line {
+    pub fn data<D: Into<DataPoint>>(mut self, data: Vec<D>) -> Self {
+        self.data = data.into_iter().map(|d| d.into()).collect();
+        self
+    }
+}
+
+```
+*/
+
+use syn::visit::Visit;
+
+#[proc_macro_derive(CharmingSetter, attributes(charming_skip_setter, charming_type))]
+pub fn charming_derive(input: proc_macro::TokenStream) -> proc_macro::TokenStream {
+    let input = syn::parse_macro_input!(input as syn::DeriveInput);
+
+    let ident = input.ident;
+    let mut field_list = vec![];
+    let mut method_list = vec![];
+
+    let fields = match &input.data {
+        syn::Data::Struct(ref data) => match data.fields {
+            syn::Fields::Named(ref fields) => fields.named.iter().collect::<Vec<_>>(),
+            _ => unimplemented!(
+                "Can't implement CharmingSetter on a unit struct or a struct with unnamed fields"
+            ),
+        },
+        syn::Data::Enum(_data_enum) => unimplemented!("Can't implement CharmingSetter on an Enum"),
+        syn::Data::Union(_data_union) => {
+            unimplemented!("Can't implement CharmingSetter on a Union")
+        }
+    };
+
+    'outer: for field in fields {
+        let field_ident = field.ident.as_ref().unwrap();
+        let field_types = gather_all_type_reprs(&field.ty);
+        let type_ident =
+            syn::Ident::new(field_types.last().unwrap(), proc_macro2::Span::call_site());
+        let shorthand_char = field_types.last().unwrap().chars().next().unwrap();
+        let shorthand = syn::Ident::new(
+            &shorthand_char.to_string().to_uppercase(),
+            proc_macro2::Span::call_site(),
+        );
+
+        for attribute in &field.attrs {
+            match &attribute.meta {
+                syn::Meta::Path(path) => {
+                    if let Some(segment) = path.segments.last() {
+                        if let "charming_skip_setter" = segment.ident.to_string().as_str() {
+                            if field_types[0].starts_with("Option") {
+                                field_list.push(quote::quote! { #field_ident: None, });
+                            } else if field_types[0].starts_with("Vec") {
+                                field_list
+                                    .push(quote::quote! { #field_ident: std::vec::Vec::new(), });
+                            }
+                            continue 'outer;
+                        }
+                    }
+                }
+                syn::Meta::List(_meta_list) => {}
+                syn::Meta::NameValue(meta_name_value) => {
+                    if let Some(segment) = meta_name_value.path.segments.last() {
+                        if segment.ident.to_string().starts_with("charming_type") {
+                            match &meta_name_value.value {
+                                syn::Expr::Lit(expr_lit) => {
+                                    if let syn::Lit::Str(string_lit) = &expr_lit.lit {
+                                        let value = string_lit.value();
+                                        field_list.push(
+                                            quote::quote! { #field_ident: #value.to_string(), },
+                                        );
+                                    } else {
+                                        unimplemented!("Expected string literal for charming_type")
+                                    }
+                                    continue 'outer;
+                                }
+                                _ => {
+                                    unimplemented!("Can't implement non Literals for charming_type")
+                                }
+                            }
+                        }
+                    }
+                }
+            }
+        }
+        if field_types[0].starts_with("Option") {
+            field_list.push(quote::quote! { #field_ident: None, });
+            method_list.push(quote::quote! {
+                pub fn #field_ident<#shorthand: Into<#type_ident>>(mut self, #field_ident: #shorthand) -> Self {
+                    self.#field_ident = Some(#field_ident.into());
+                    self
+                }
+            });
+        } else if field_types[0].starts_with("Vec") {
+            field_list.push(quote::quote! { #field_ident: std::vec::Vec::new(), });
+            method_list.push(quote::quote! {
+                pub fn #field_ident<#shorthand: Into<#type_ident>>(mut self, #field_ident: #shorthand) -> Self {
+                    self.#field_ident.push(#field_ident.into());
+                    self
+                }
+            });
+        }
+    }
+
+    quote::quote!(
+        impl #ident {
+            pub fn new() -> Self {
+                Self {
+                    #(#field_list)*
+                }
+            }
+            #(#method_list)*
+        }
+    )
+    .into()
+}
+
+// Following code is from enso_macro_utils but supports syn2.0
+
+#[derive(Default)]
+struct TypeGatherer<'ast> {
+    /// Observed types accumulator.
+    pub types: Vec<&'ast syn::TypePath>,
+}
+
+impl<'ast> syn::visit::Visit<'ast> for TypeGatherer<'ast> {
+    fn visit_type_path(&mut self, node: &'ast syn::TypePath) {
+        self.types.push(node);
+        syn::visit::visit_type_path(self, node);
+    }
+}
+
+fn gather_all_types(node: &syn::Type) -> Vec<&syn::TypePath> {
+    let mut type_gatherer = TypeGatherer::default();
+    type_gatherer.visit_type(node);
+    type_gatherer.types
+}
+
+fn gather_all_type_reprs(node: &syn::Type) -> Vec<String> {
+    gather_all_types(node).iter().map(repr).collect()
+}
+
+fn repr<T: quote::ToTokens>(t: &T) -> String {
+    quote::quote!(#t).to_string()
+}

charming-derive/tests/derive_test.rs

@@ -0,0 +1,36 @@
+use charming_derive::CharmingSetter;
+use serde::Serialize;
+
+#[derive(Serialize, Debug, Clone, CharmingSetter)]
+#[serde(rename_all = "camelCase")]
+struct LineComponent {
+    #[serde(rename = "type")]
+    #[charming_type = "line"]
+    type_: String,
+
+    #[serde(skip_serializing_if = "Option::is_none")]
+    name: Option<String>,
+
+    #[serde(skip_serializing_if = "Vec::is_empty")]
+    title: Vec<String>,
+
+    #[serde(skip_serializing_if = "Vec::is_empty")]
+    #[charming_skip_setter]
+    data: Vec<i32>,
+}
+
+impl LineComponent {
+    pub fn data<I: Into<i32>>(mut self, data: Vec<I>) -> Self {
+        self.data = data.into_iter().map(|d| d.into()).collect();
+        self
+    }
+}
+
+#[test]
+fn expand_test() {
+    LineComponent::new()
+        .name("LineComponent")
+        .title("Title 1")
+        .title("Title 2")
+        .data(vec![1, 2, 3]);
+}

charming/Cargo.toml

@@ -17,23 +17,20 @@ handlebars = { version = "4.3", optional = true }
 image = { version = "0.24", optional = true }
 resvg = { version = "0.36", optional = true }
 serde = { version = "1.0", features = ["derive"] }
-serde-wasm-bindgen = {version = "0.6", optional = true }
+serde-wasm-bindgen = { version = "0.6", optional = true }
 serde_json = "1.0"
 serde_v8 = { version = "0.220", optional = true }
 serde_with = "3.11.0"
 wasm-bindgen = { version = "0.2", optional = true }
+charming-derive = { path = "../charming-derive" }
 
 [dev-dependencies]
 assert-json-diff = "2.0.2"
 
 [dependencies.web-sys]
 version = "0.3.64"
 optional = true
-features = [
-    "Window",
-    "Document",
-    "Element",
-]
+features = ["Window", "Document", "Element"]
 
 [features]
 default = ["html"]