Support crate renaming in proc macros.

See: rust-lang/rust#54363

Author: artob

lib/protoflow-derive/Cargo.toml

@@ -22,6 +22,7 @@ default = []
 
 [dependencies]
 proc-macro2 = { version = "1", default-features = false }
+proc-macro-crate = "3.1"
 quote = { version = "1", default-features = false }
 syn = { version = "2", default-features = true }
 

lib/protoflow-derive/src/derives/block.rs

@@ -1,10 +1,12 @@
 // This is free and unencumbered software released into the public domain.
 
+use crate::util::protoflow_crate;
 use proc_macro2::TokenStream;
 use quote::quote;
 use syn::{self, Data, DataStruct, DeriveInput, Fields, FieldsNamed, FieldsUnnamed};
 
 pub(crate) fn expand_derive_block(input: &DeriveInput) -> Result<TokenStream, syn::Error> {
+    let protoflow = protoflow_crate();
     let ident = &input.ident;
     let generics = &input.generics;
     let (impl_generics, ty_generics, where_clause) = generics.split_for_impl();
@@ -33,13 +35,13 @@ pub(crate) fn expand_derive_block(input: &DeriveInput) -> Result<TokenStream, sy
             unused_qualifications,
             clippy::redundant_locals,
         )]
-        impl #impl_generics protoflow::BlockDescriptor for #ident #ty_generics #where_clause {
-            fn inputs(&self) -> protoflow::prelude::Vec<protoflow::PortDescriptor> {
-                protoflow::prelude::vec![] // TODO
+        impl #impl_generics #protoflow::BlockDescriptor for #ident #ty_generics #where_clause {
+            fn inputs(&self) -> #protoflow::prelude::Vec<#protoflow::PortDescriptor> {
+                #protoflow::prelude::vec![] // TODO
             }
 
-            fn outputs(&self) -> protoflow::prelude::Vec<protoflow::PortDescriptor> {
-                protoflow::prelude::vec![] // TODO
+            fn outputs(&self) -> #protoflow::prelude::Vec<#protoflow::PortDescriptor> {
+                #protoflow::prelude::vec![] // TODO
             }
         }
     })

lib/protoflow-derive/src/derives/function_block.rs

@@ -1,10 +1,12 @@
 // This is free and unencumbered software released into the public domain.
 
+use crate::util::protoflow_crate;
 use proc_macro2::TokenStream;
 use quote::quote;
 use syn::{self, Data, DataStruct, DeriveInput, Fields, FieldsNamed, FieldsUnnamed};
 
 pub(crate) fn expand_derive_function_block(input: &DeriveInput) -> Result<TokenStream, syn::Error> {
+    let protoflow = protoflow_crate();
     let ident = &input.ident;
     let generics = &input.generics;
     let (impl_generics, ty_generics, where_clause) = generics.split_for_impl();
@@ -33,13 +35,13 @@ pub(crate) fn expand_derive_function_block(input: &DeriveInput) -> Result<TokenS
             unused_qualifications,
             clippy::redundant_locals,
         )]
-        impl #impl_generics protoflow::BlockDescriptor for #ident #ty_generics #where_clause {
-            fn inputs(&self) -> protoflow::prelude::Vec<protoflow::PortDescriptor> {
-                protoflow::prelude::vec![protoflow::PortDescriptor::from(&self.0)]
+        impl #impl_generics #protoflow::BlockDescriptor for #ident #ty_generics #where_clause {
+            fn inputs(&self) -> #protoflow::prelude::Vec<#protoflow::PortDescriptor> {
+                #protoflow::prelude::vec![#protoflow::PortDescriptor::from(&self.0)]
             }
 
-            fn outputs(&self) -> protoflow::prelude::Vec<protoflow::PortDescriptor> {
-                protoflow::prelude::vec![protoflow::PortDescriptor::from(&self.1)]
+            fn outputs(&self) -> #protoflow::prelude::Vec<#protoflow::PortDescriptor> {
+                #protoflow::prelude::vec![#protoflow::PortDescriptor::from(&self.1)]
             }
         }
 
@@ -48,14 +50,14 @@ pub(crate) fn expand_derive_function_block(input: &DeriveInput) -> Result<TokenS
             unused_qualifications,
             clippy::redundant_locals,
         )]
-        impl #impl_generics protoflow::Block for #ident #ty_generics #where_clause {
-            fn execute(&mut self, runtime: &dyn protoflow::Runtime) -> protoflow::BlockResult<()> {
+        impl #impl_generics #protoflow::Block for #ident #ty_generics #where_clause {
+            fn execute(&mut self, runtime: &dyn #protoflow::Runtime) -> #protoflow::BlockResult<()> {
                 let input = &self.0;
                 let output = &self.1;
-                while let Some(message) = protoflow::InputPort::receive(input)? {
-                    if protoflow::Port::is_connected(output) {
-                        let result = protoflow::FunctionBlock::compute(self, message)?;
-                        protoflow::OutputPort::send(output, &result)?;
+                while let Some(message) = #protoflow::InputPort::receive(input)? {
+                    if #protoflow::Port::is_connected(output) {
+                        let result = #protoflow::FunctionBlock::compute(self, message)?;
+                        #protoflow::OutputPort::send(output, &result)?;
                     }
                 }
                 Ok(())

lib/protoflow-derive/src/derives/system.rs

@@ -1,10 +1,12 @@
 // This is free and unencumbered software released into the public domain.
 
+use crate::util::protoflow_crate;
 use proc_macro2::TokenStream;
 use quote::quote;
 use syn::{self, Data, DataStruct, DeriveInput, Fields, FieldsNamed, FieldsUnnamed};
 
 pub(crate) fn expand_derive_system(input: &DeriveInput) -> Result<TokenStream, syn::Error> {
+    let protoflow = protoflow_crate();
     let ident = &input.ident;
     let generics = &input.generics;
     let (impl_generics, ty_generics, where_clause) = generics.split_for_impl();
@@ -33,6 +35,6 @@ pub(crate) fn expand_derive_system(input: &DeriveInput) -> Result<TokenStream, s
             unused_qualifications,
             clippy::redundant_locals,
         )]
-        impl #impl_generics protoflow::System for #ident #ty_generics #where_clause {}
+        impl #impl_generics #protoflow::System for #ident #ty_generics #where_clause {}
     })
 }

lib/protoflow-derive/src/lib.rs

@@ -9,6 +9,7 @@
 extern crate proc_macro;
 
 mod derives;
+pub(crate) mod util;
 
 use proc_macro::TokenStream;
 use syn::{parse_macro_input, DeriveInput};

lib/protoflow-derive/src/util.rs

@@ -0,0 +1,17 @@
+// This is free and unencumbered software released into the public domain.
+
+use proc_macro2::{Span, TokenStream};
+use proc_macro_crate::{crate_name, FoundCrate};
+use quote::quote;
+use syn::Ident;
+
+pub(crate) fn protoflow_crate() -> TokenStream {
+    let found_crate = crate_name("protoflow").expect("protoflow is present in `Cargo.toml`");
+    match found_crate {
+        FoundCrate::Itself => quote!(crate),
+        FoundCrate::Name(name) => {
+            let ident = Ident::new(&name, Span::call_site());
+            quote!(#ident)
+        }
+    }
+}

lib/protoflow/src/lib.rs

@@ -2,6 +2,7 @@
 
 #![no_std]
 
+#[doc(hidden)]
 pub mod prelude;
 
 mod block;