Upstream yewtil crate (#1119)

* Upstream yewtil crate

* cargo fmt

* cargo clippy

* cargo fmt

Cargo.toml

@@ -13,6 +13,19 @@ members = [
   "yew-router/examples/router_component",
   "yew-router/examples/switch",
 
+  # Utilities
+  "yewtil",
+  "yewtil-macro",
+  "yewtil/examples/pure_component",
+  # "yewtil/examples/dsl",
+  "yewtil/examples/lrc",
+  "yewtil/examples/history",
+  "yewtil/examples/mrc_irc",
+  "yewtil/examples/effect",
+  "yewtil/examples/fetch",
+  "yewtil/examples/futures",
+  "yewtil/examples/function_component",
+
   # Examples
   "examples/counter",
   "examples/crm",

yewtil-macro/Cargo.toml

@@ -0,0 +1,15 @@
+[package]
+name = "yewtil-macro"
+version = "0.1.0"
+authors = ["Henry Zimmerman <zimhen7@gmail.com>"]
+edition = "2018"
+license = "MIT/Apache-2.0"
+description = "Macros to be re-exported from the yewtil crate"
+
+[lib]
+proc-macro = true
+
+[dependencies]
+proc-macro2 = "1.0.6"
+quote = "1.0.2"
+syn = { version = "1.0.11", features = ["full", "extra-traits"] }

yewtil-macro/src/function_component.rs

@@ -0,0 +1,194 @@
+use proc_macro::TokenStream as TokenStream1;
+use proc_macro2::{Ident, Span, TokenStream};
+use quote::quote;
+use syn::export::ToTokens;
+use syn::parse::{Parse, ParseBuffer};
+use syn::parse_macro_input;
+use syn::punctuated::Punctuated;
+use syn::token;
+use syn::Token;
+use syn::{braced, parenthesized};
+use syn::{Block, Error, Field, Stmt, Type, VisPublic, Visibility};
+
+pub fn function_component_handler(attr: TokenStream, item: TokenStream1) -> TokenStream1 {
+    let component_name = attr.to_string();
+    assert!(
+        !component_name.is_empty(),
+        "you must provide a component name. eg: function_component(MyComponent)"
+    );
+    let component_name = Ident::new(&component_name, Span::call_site());
+    let function = parse_macro_input!(item as Function);
+    TokenStream1::from(
+        FunctionComponentInfo {
+            component_name,
+            function,
+        }
+        .to_token_stream(),
+    )
+}
+
+pub struct FunctionComponentInfo {
+    component_name: Ident,
+    function: Function,
+}
+
+// TODO, support type parameters
+
+pub struct Function {
+    pub vis: Visibility,
+    pub fn_token: Token![fn],
+    pub name: Ident,
+    pub paren_token: token::Paren,
+    pub fields: Punctuated<Field, Token![,]>,
+    pub returns_token: Token![->],
+    pub return_ty: Ident,
+    pub brace_token: token::Brace,
+    pub body: Vec<Stmt>,
+}
+
+impl Parse for Function {
+    fn parse(input: &ParseBuffer) -> Result<Self, Error> {
+        let vis = input.parse()?;
+        let fn_token = input.parse()?;
+        let name = input.parse()?;
+        let content;
+        let paren_token = parenthesized!(content in input);
+        let returns_token = input.parse()?;
+        let return_ty = input.parse()?;
+        let content2;
+        let brace_token = braced!(content2 in input);
+        Ok(Function {
+            vis,
+            fn_token,
+            name,
+            paren_token,
+            fields: content.parse_terminated(Field::parse_named)?,
+            returns_token,
+            return_ty,
+            brace_token,
+            body: content2.call(Block::parse_within)?,
+        })
+    }
+}
+
+impl ToTokens for Function {
+    fn to_tokens(&self, tokens: &mut TokenStream) {
+        let Function {
+            vis,
+            fn_token,
+            name,
+            fields,
+            returns_token,
+            return_ty,
+            body,
+            ..
+        } = self;
+        let fields = fields
+            .iter()
+            .map(|field: &Field| {
+                let mut new_field: Field = field.clone();
+                new_field.attrs = vec![];
+                new_field
+            })
+            .collect::<Punctuated<_, Token![,]>>();
+
+        tokens.extend(quote! {
+            #vis #fn_token #name(#fields) #returns_token #return_ty {
+                #(#body)*
+            }
+        })
+    }
+}
+
+impl ToTokens for FunctionComponentInfo {
+    fn to_tokens(&self, tokens: &mut TokenStream) {
+        let FunctionComponentInfo {
+            component_name,
+            function,
+        } = self;
+        // The function tokens must be re-generated in order to strip the attributes that are not allowed.
+        let function_token_stream = function.to_token_stream();
+        let Function {
+            vis, name, fields, ..
+        } = function;
+
+        let impl_name = format!("FuncComp{}", component_name.to_string());
+        let impl_name = Ident::new(&impl_name, Span::call_site());
+
+        let alias = quote! {
+            #vis type #component_name = ::yewtil::Pure<#impl_name>;
+        };
+
+        // Set the fields to be public and strips references as necessary.
+        // This will preserve attributes like #[props(required)], which will appear in the generated struct below.
+        let new_fields = fields
+            .iter()
+            .map(|field: &Field| {
+                let mut new_field: Field = field.clone();
+                let visibility = Visibility::Public(VisPublic {
+                    pub_token: syn::token::Pub {
+                        span: Span::call_site(),
+                    },
+                });
+                // Strip references so the component can have a static lifetime.
+                // TODO Handle 'static lifetimes gracefully here - allowing &'static strings instead of erroneously converting them to plain strs.
+                let ty = match &field.ty {
+                    Type::Reference(x) => {
+                        let elem = x.elem.clone();
+                        Type::Verbatim(quote! {
+                            #elem
+                        })
+                    }
+                    x => x.clone(),
+                };
+                new_field.vis = visibility;
+                new_field.ty = ty;
+                new_field
+            })
+            .collect::<Punctuated<_, Token![,]>>();
+
+        let component_struct = quote! {
+            #[derive(::std::clone::Clone, ::std::cmp::PartialEq, ::yew::Properties)]
+            #vis struct #impl_name {
+                #new_fields
+            }
+        };
+
+        let arguments = fields
+            .iter()
+            .zip(new_fields.iter())
+            .map(|(field, new_field): (&Field, &Field)| {
+                let field_name = field.ident.as_ref().expect("Field must have name");
+
+                // If the fields differ, then a reference was removed from the function's field's type
+                // to make it static.
+                // Otherwise it is assumed that the type is not a reference on the function and it
+                // implements clone, and that when calling the function, the type should be cloned again.
+                if field.ty != new_field.ty {
+                    quote! {
+                        &self.#field_name
+                    }
+                } else {
+                    quote! {
+                        self.#field_name.clone()
+                    }
+                }
+            })
+            .collect::<Punctuated<_, Token![,]>>();
+
+        let pure_component_impl = quote! {
+            impl ::yewtil::PureComponent for #impl_name {
+                fn render(&self) -> ::yew::Html {
+                     #name(#arguments)
+                }
+            }
+        };
+
+        tokens.extend(quote! {
+            #function_token_stream
+            #alias
+            #component_struct
+            #pure_component_impl
+        })
+    }
+}

yewtil-macro/src/lib.rs

@@ -0,0 +1,10 @@
+extern crate proc_macro;
+use proc_macro::TokenStream;
+
+use crate::function_component::function_component_handler;
+
+mod function_component;
+#[proc_macro_attribute]
+pub fn function_component(attr: TokenStream, item: TokenStream) -> TokenStream {
+    function_component_handler(attr.into(), item)
+}

yewtil/CHANGELOG.md

@@ -0,0 +1,20 @@
+# Changelog
+
+<!-- START TEMPLATE
+
+## ✨ **VERSION** *(DATE)*
+
+- #### ⚡️ Features
+  - Sample
+- #### 🛠 Fixes
+  - Sample
+- #### 🚨 Breaking changes
+  - Sample
+
+END TEMPLATE-->
+
+## ✨ **v0.2.0** *11/18/19*
+- #### ⚡️ Features
+  - Add new `FetchRequest` trait, `fetch_resource()` function, and `FetchState` enum 
+  to simplify making fetch requests using futures.
+  - Add `Default` implementations to `Irc` and `Mrc`.

yewtil/Cargo.toml

@@ -0,0 +1,68 @@
+[package]
+name = "yewtil"
+version = "0.2.0"
+authors = ["Henry Zimmerman <zimhen7@gmail.com>"]
+edition = "2018"
+description = "Utility crate for Yew"
+license = "MIT/Apache-2.0"
+repository = "https://github.com/yewstack/yewtil"
+readme = "Readme.md"
+
+[features]
+default = ["stable"] # Only stable is included by default.
+all = ["stable", "experimental"]
+
+# Broad features
+## All features MUST be stable or experimental
+stable = ["neq", "pure", "history", "mrc_irc", "effect", "future"]
+experimental = ["dsl", "lrc", "with_callback", "fetch" ]
+
+# Some pointers are stable, some experimental.
+# This makes sure you get all the pointers
+ptr = ["lrc", "mrc_irc"]
+
+# Misc features
+neq = []
+pure = ["neq", "yewtil-macro"]
+with_callback = []
+history = []
+dsl = []
+effect = []
+fetch = ["serde", "serde_json", "neq", "future"]
+future = ["wasm-bindgen-futures", "wasm-bindgen", "stdweb", "futures", "web-sys"]
+
+# Ptr features
+lrc = []
+mrc_irc = []
+
+[dependencies]
+futures = {version = "0.3.1", optional = true}
+log = "0.4.8"
+serde = {version= "1.0.102", optional = true}
+serde_json = { version = "1.0.41", optional = true }
+wasm-bindgen = {version = "0.2.51", features=["serde-serialize"], optional = true}
+wasm-bindgen-futures = {version = "0.4.3", optional = true}
+yew = { path = "../yew" }
+yewtil-macro = { path = "../yewtil-macro", optional = true }
+
+[dependencies.stdweb]
+version = "0.4.20"
+optional = true
+features = [
+  "futures-support",
+  "experimental_features_which_may_break_on_minor_version_bumps",
+]
+
+[dependencies.web-sys]
+version = "0.3.31"
+optional = true
+features = [
+  'Headers',
+  'Request',
+  'RequestInit',
+  'RequestMode',
+  'Response',
+  'Window',
+  'Location',
+  'Storage',
+]