forge_sol_macro_gen/
sol_macro_gen.rs

1//! SolMacroGen and MultiSolMacroGen
2//!
3//! This type encapsulates the logic for expansion of a Rust TokenStream from Solidity tokens. It
4//! uses the `expand` method from `alloy_sol_macro_expander` underneath.
5//!
6//! It holds info such as `path` to the ABI file, `name` of the file and the rust binding being
7//! generated, and lastly the `expansion` itself, i.e the Rust binding for the provided ABI.
8//!
9//! It contains methods to read the json abi, generate rust bindings from the abi and ultimately
10//! write the bindings to a crate or modules.
11
12use alloy_sol_macro_expander::expand::expand;
13use alloy_sol_macro_input::{SolInput, SolInputKind};
14use eyre::{Context, OptionExt, Result};
15use foundry_common::fs;
16use proc_macro2::{Span, TokenStream};
17use std::{
18    fmt::Write,
19    path::{Path, PathBuf},
20    str::FromStr,
21};
22
23use heck::ToSnakeCase;
24
25const SERDE_ARRAY_IMPL_MAX_LEN: usize = 32;
26const SERDE_WITH_DEP: &str =
27    r#"serde_with = { version = "3.15", default-features = false, features = ["std"] }"#;
28
29pub struct SolMacroGen {
30    pub path: PathBuf,
31    pub name: String,
32    pub expansion: Option<TokenStream>,
33    needs_serde_with: bool,
34}
35
36impl SolMacroGen {
37    pub const fn new(path: PathBuf, name: String) -> Self {
38        Self { path, name, expansion: None, needs_serde_with: false }
39    }
40
41    pub fn get_sol_input(&self) -> Result<SolInput> {
42        let path = self.path.to_string_lossy().into_owned();
43        let name = proc_macro2::Ident::new(&self.name, Span::call_site());
44        let tokens = quote::quote! {
45            #[sol(ignore_unlinked)]
46            #name,
47            #path
48        };
49
50        let sol_input: SolInput = syn::parse2(tokens).wrap_err("failed to parse input")?;
51
52        Ok(sol_input)
53    }
54}
55
56pub struct MultiSolMacroGen {
57    pub instances: Vec<SolMacroGen>,
58}
59
60impl MultiSolMacroGen {
61    pub const fn new(instances: Vec<SolMacroGen>) -> Self {
62        Self { instances }
63    }
64
65    pub fn populate_expansion(&mut self, bindings_path: &Path) -> Result<()> {
66        for instance in &mut self.instances {
67            let path = bindings_path.join(format!("{}.rs", instance.name.to_snake_case()));
68            let expansion = fs::read_to_string(path).wrap_err("Failed to read file")?;
69
70            let tokens = TokenStream::from_str(&expansion)
71                .map_err(|e| eyre::eyre!("Failed to parse TokenStream: {e}"))?;
72            instance.expansion = Some(tokens);
73        }
74        Ok(())
75    }
76
77    pub fn generate_bindings(&mut self, all_derives: bool) -> Result<()> {
78        for instance in &mut self.instances {
79            Self::generate_binding(instance, all_derives).wrap_err_with(|| {
80                format!(
81                    "failed to generate bindings for {}:{}",
82                    instance.path.display(),
83                    instance.name
84                )
85            })?;
86        }
87
88        Ok(())
89    }
90
91    fn generate_binding(instance: &mut SolMacroGen, all_derives: bool) -> Result<()> {
92        let input = instance.get_sol_input()?.normalize_json()?;
93        let SolInput { attrs: _, path: _, kind } = input;
94
95        let tokens = match kind {
96            SolInputKind::Sol(mut file) => {
97                let sol_attr: syn::Attribute = if all_derives {
98                    syn::parse_quote! {
99                            #[sol(rpc, alloy_sol_types = alloy::sol_types, alloy_contract =
100                    alloy::contract, all_derives = true, extra_derives(serde::Serialize,
101                    serde::Deserialize))]     }
102                } else {
103                    syn::parse_quote! {
104                            #[sol(rpc, alloy_sol_types = alloy::sol_types, alloy_contract =
105                    alloy::contract)]     }
106                };
107                file.attrs.push(sol_attr);
108                expand(file).wrap_err("failed to expand")?
109            }
110            _ => unreachable!(),
111        };
112
113        let (tokens, needs_serde_with) =
114            if all_derives { add_large_array_serde_attrs(tokens)? } else { (tokens, false) };
115
116        instance.expansion = Some(tokens);
117        instance.needs_serde_with = needs_serde_with;
118        Ok(())
119    }
120
121    #[allow(clippy::too_many_arguments)]
122    pub fn write_to_crate(
123        &mut self,
124        name: &str,
125        version: &str,
126        description: &str,
127        license: &str,
128        bindings_path: &Path,
129        single_file: bool,
130        alloy_version: Option<String>,
131        alloy_rev: Option<String>,
132        all_derives: bool,
133    ) -> Result<()> {
134        self.generate_bindings(all_derives)?;
135
136        let src = bindings_path.join("src");
137        fs::create_dir_all(&src)?;
138
139        // Write Cargo.toml
140        let cargo_toml_path = bindings_path.join("Cargo.toml");
141        let mut toml_contents = format!(
142            r#"[package]
143name = "{name}"
144version = "{version}"
145edition = "2021"
146"#
147        );
148
149        if !description.is_empty() {
150            toml_contents.push_str(&format!("description = \"{description}\"\n"));
151        }
152
153        if !license.is_empty() {
154            let formatted_licenses: Vec<String> =
155                license.split(',').map(Self::parse_license_alias).collect();
156
157            let formatted_license = formatted_licenses.join(" OR ");
158            toml_contents.push_str(&format!("license = \"{formatted_license}\"\n"));
159        }
160
161        toml_contents.push_str("\n[dependencies]\n");
162
163        let alloy_dep = Self::get_alloy_dep(alloy_version, alloy_rev);
164        write!(toml_contents, "{alloy_dep}")?;
165
166        if all_derives {
167            let serde_dep = r#"serde = { version = "1.0", features = ["derive"] }"#;
168            write!(toml_contents, "\n{serde_dep}")?;
169            if self.instances.iter().any(|instance| instance.needs_serde_with) {
170                write!(toml_contents, "\n{SERDE_WITH_DEP}")?;
171            }
172        }
173
174        fs::write(cargo_toml_path, toml_contents).wrap_err("Failed to write Cargo.toml")?;
175
176        let mut lib_contents = String::new();
177        write!(
178            &mut lib_contents,
179            r#"#![allow(unused_imports, unused_attributes, clippy::all, rustdoc::all)]
180        //! This module contains the sol! generated bindings for solidity contracts.
181        //! This is autogenerated code.
182        //! Do not manually edit these files.
183        //! These files may be overwritten by the codegen system at any time.
184        "#
185        )?;
186
187        // Write src
188        let parse_error = |name: &str| {
189            format!("failed to parse generated tokens as an AST for {name};\nthis is likely a bug")
190        };
191        for instance in &self.instances {
192            let contents = instance.expansion.as_ref().unwrap();
193
194            let name = instance.name.to_snake_case();
195            let path = src.join(format!("{name}.rs"));
196            let file = syn::parse2(contents.clone())
197                .wrap_err_with(|| parse_error(&format!("{}:{}", path.display(), name)))?;
198            let contents = qualify_shadowed_sibling_module_paths(prettyplease::unparse(&file));
199            if single_file {
200                write!(&mut lib_contents, "{contents}")?;
201            } else {
202                fs::write(path, contents).wrap_err("failed to write to file")?;
203                write_mod_name(&mut lib_contents, &name)?;
204            }
205        }
206
207        let lib_path = src.join("lib.rs");
208        let lib_file = syn::parse_file(&lib_contents).wrap_err_with(|| parse_error("lib.rs"))?;
209        let lib_contents = prettyplease::unparse(&lib_file);
210        fs::write(lib_path, lib_contents).wrap_err("Failed to write lib.rs")?;
211
212        Ok(())
213    }
214
215    /// Attempts to detect the appropriate license.
216    pub fn parse_license_alias(license: &str) -> String {
217        match license.trim().to_lowercase().as_str() {
218            "mit" => "MIT".to_string(),
219            "apache" | "apache2" | "apache20" | "apache2.0" => "Apache-2.0".to_string(),
220            "gpl" | "gpl3" => "GPL-3.0".to_string(),
221            "lgpl" | "lgpl3" => "LGPL-3.0".to_string(),
222            "agpl" | "agpl3" => "AGPL-3.0".to_string(),
223            "bsd" | "bsd3" => "BSD-3-Clause".to_string(),
224            "bsd2" => "BSD-2-Clause".to_string(),
225            "mpl" | "mpl2" => "MPL-2.0".to_string(),
226            "isc" => "ISC".to_string(),
227            "unlicense" => "Unlicense".to_string(),
228            _ => license.trim().to_string(),
229        }
230    }
231
232    pub fn write_to_module(
233        &mut self,
234        bindings_path: &Path,
235        single_file: bool,
236        all_derives: bool,
237    ) -> Result<()> {
238        self.generate_bindings(all_derives)?;
239
240        fs::create_dir_all(bindings_path)?;
241
242        let mut mod_contents =
243            r#"#![allow(unused_imports, unused_attributes, clippy::all, rustdoc::all)]
244        //! This module contains the sol! generated bindings for solidity contracts.
245        //! This is autogenerated code.
246        //! Do not manually edit these files.
247        //! These files may be overwritten by the codegen system at any time.
248        "#
249            .to_string();
250
251        for instance in &self.instances {
252            let name = instance.name.to_snake_case();
253            if single_file {
254                // Single File
255                let mut contents = String::new();
256                write!(contents, "{}\n\n", instance.expansion.as_ref().unwrap())?;
257                write!(mod_contents, "{contents}")?;
258            } else {
259                // Module
260                write_mod_name(&mut mod_contents, &name)?;
261                let mut contents = String::new();
262
263                write!(contents, "{}", instance.expansion.as_ref().unwrap())?;
264                let file = syn::parse_file(&contents)?;
265
266                let contents = qualify_shadowed_sibling_module_paths(prettyplease::unparse(&file));
267                fs::write(bindings_path.join(format!("{name}.rs")), contents)
268                    .wrap_err("Failed to write file")?;
269            }
270        }
271
272        let mod_path = bindings_path.join("mod.rs");
273        let mod_file = syn::parse_file(&mod_contents)?;
274        let mod_contents = qualify_shadowed_sibling_module_paths(prettyplease::unparse(&mod_file));
275
276        fs::write(mod_path, mod_contents).wrap_err("Failed to write mod.rs")?;
277
278        Ok(())
279    }
280
281    /// Checks that the generated bindings are up to date with the latest version of
282    /// `sol!`.
283    ///
284    /// Returns `Ok(())` if the generated bindings are up to date, otherwise it returns
285    /// `Err(_)`.
286    #[expect(clippy::too_many_arguments)]
287    pub fn check_consistency(
288        &self,
289        name: &str,
290        version: &str,
291        crate_path: &Path,
292        single_file: bool,
293        check_cargo_toml: bool,
294        is_mod: bool,
295        alloy_version: Option<String>,
296        alloy_rev: Option<String>,
297    ) -> Result<()> {
298        if check_cargo_toml && !is_mod {
299            self.check_cargo_toml(name, version, crate_path, alloy_version, alloy_rev)?;
300        }
301
302        let mut super_contents = String::new();
303        write!(
304            &mut super_contents,
305            r#"#![allow(unused_imports, unused_attributes, clippy::all, rustdoc::all)]
306            //! This module contains the sol! generated bindings for solidity contracts.
307            //! This is autogenerated code.
308            //! Do not manually edit these files.
309            //! These files may be overwritten by the codegen system at any time.
310            "#
311        )?;
312        if !single_file {
313            for instance in &self.instances {
314                let name = instance.name.to_snake_case();
315                let path = if is_mod {
316                    crate_path.join(format!("{name}.rs"))
317                } else {
318                    crate_path.join(format!("src/{name}.rs"))
319                };
320                let tokens = instance
321                    .expansion
322                    .as_ref()
323                    .ok_or_eyre(format!("TokenStream for {path:?} does not exist"))?
324                    .to_string();
325
326                self.check_file_contents(&path, &tokens)?;
327                write_mod_name(&mut super_contents, &name)?;
328            }
329
330            let super_path =
331                if is_mod { crate_path.join("mod.rs") } else { crate_path.join("src/lib.rs") };
332            self.check_file_contents(&super_path, &super_contents)?;
333        }
334
335        Ok(())
336    }
337
338    fn check_file_contents(&self, file_path: &Path, expected_contents: &str) -> Result<()> {
339        eyre::ensure!(file_path.is_file(), "{} is not a file", file_path.display());
340        let file_contents = &fs::read_to_string(file_path).wrap_err("Failed to read file")?;
341
342        // Format both
343        let file_contents = syn::parse_file(file_contents)?;
344        let formatted_file = prettyplease::unparse(&file_contents);
345
346        let expected_contents = syn::parse_file(expected_contents)?;
347        let formatted_exp =
348            qualify_shadowed_sibling_module_paths(prettyplease::unparse(&expected_contents));
349
350        eyre::ensure!(
351            formatted_file == formatted_exp,
352            "File contents do not match expected contents for {file_path:?}"
353        );
354        Ok(())
355    }
356
357    fn check_cargo_toml(
358        &self,
359        name: &str,
360        version: &str,
361        crate_path: &Path,
362        alloy_version: Option<String>,
363        alloy_rev: Option<String>,
364    ) -> Result<()> {
365        eyre::ensure!(crate_path.is_dir(), "Crate path must be a directory");
366
367        let cargo_toml_path = crate_path.join("Cargo.toml");
368
369        eyre::ensure!(cargo_toml_path.is_file(), "Cargo.toml must exist");
370        let cargo_toml_contents =
371            fs::read_to_string(cargo_toml_path).wrap_err("Failed to read Cargo.toml")?;
372
373        let name_check = format!("name = \"{name}\"");
374        let version_check = format!("version = \"{version}\"");
375        let alloy_dep_check = Self::get_alloy_dep(alloy_version, alloy_rev);
376        let serde_with_consistent =
377            !self.instances.iter().any(|instance| instance.needs_serde_with)
378                || cargo_toml_contents.contains(SERDE_WITH_DEP);
379        let toml_consistent = cargo_toml_contents.contains(&name_check)
380            && cargo_toml_contents.contains(&version_check)
381            && cargo_toml_contents.contains(&alloy_dep_check)
382            && serde_with_consistent;
383        eyre::ensure!(
384            toml_consistent,
385            r#"The contents of Cargo.toml do not match the expected output of the latest `sol!` version.
386                This indicates that the existing bindings are outdated and need to be generated again."#
387        );
388
389        Ok(())
390    }
391
392    /// Returns the `alloy` dependency string for the Cargo.toml file.
393    /// If `alloy_version` is provided, it will use that version from crates.io.
394    /// If `alloy_rev` is provided, it will use that revision from the GitHub repository.
395    fn get_alloy_dep(alloy_version: Option<String>, alloy_rev: Option<String>) -> String {
396        if let Some(alloy_version) = alloy_version {
397            format!(
398                r#"alloy = {{ version = "{alloy_version}", features = ["sol-types", "contract"] }}"#,
399            )
400        } else if let Some(alloy_rev) = alloy_rev {
401            format!(
402                r#"alloy = {{ git = "https://github.com/alloy-rs/alloy", rev = "{alloy_rev}", features = ["sol-types", "contract"] }}"#,
403            )
404        } else {
405            r#"alloy = { version = "1.0", features = ["sol-types", "contract"] }"#.to_string()
406        }
407    }
408}
409
410#[derive(Default)]
411struct LargeArraySerdeAttrs {
412    added: bool,
413}
414
415impl syn::visit_mut::VisitMut for LargeArraySerdeAttrs {
416    fn visit_item_struct_mut(&mut self, item: &mut syn::ItemStruct) {
417        for field in &mut item.fields {
418            if let Some(adapter) = large_array_serde_adapter(&field.ty) {
419                let adapter =
420                    syn::LitStr::new(&format!("::serde_with::As::<{adapter}>"), Span::call_site());
421                field.attrs.insert(0, syn::parse_quote!(#[serde(with = #adapter)]));
422                self.added = true;
423            }
424        }
425    }
426}
427
428/// Adds `serde_with` adapters where Serde's built-in array implementations stop.
429fn add_large_array_serde_attrs(tokens: TokenStream) -> Result<(TokenStream, bool)> {
430    let mut file = syn::parse2::<syn::File>(tokens)
431        .wrap_err("failed to parse generated bindings for large array support")?;
432    let mut visitor = LargeArraySerdeAttrs::default();
433    syn::visit_mut::VisitMut::visit_file_mut(&mut visitor, &mut file);
434    Ok((quote::quote!(#file), visitor.added))
435}
436
437fn large_array_serde_adapter(ty: &syn::Type) -> Option<String> {
438    match ty {
439        syn::Type::Array(array) => {
440            let syn::Expr::Lit(expr) = &array.len else { return None };
441            let syn::Lit::Int(length) = &expr.lit else { return None };
442            let element = large_array_serde_adapter(&array.elem);
443            let is_large =
444                length.base10_parse::<usize>().is_ok_and(|len| len > SERDE_ARRAY_IMPL_MAX_LEN);
445            if !is_large && element.is_none() {
446                return None;
447            }
448
449            let element = element.unwrap_or_else(|| "::serde_with::Same".to_string());
450            Some(format!("[{element}; {}]", length.base10_digits()))
451        }
452        syn::Type::Path(type_path) if type_path.qself.is_none() => {
453            let last = type_path.path.segments.last()?;
454            if last.ident == "Vec"
455                && let syn::PathArguments::AngleBracketed(arguments) = &last.arguments
456                && arguments.args.len() == 1
457                && let Some(syn::GenericArgument::Type(element)) = arguments.args.first()
458                && let Some(element) = large_array_serde_adapter(element)
459            {
460                Some(format!("::std::vec::Vec<{element}>"))
461            } else {
462                None
463            }
464        }
465        _ => None,
466    }
467}
468
469fn write_mod_name(contents: &mut String, name: &str) -> Result<()> {
470    if syn::parse_str::<syn::Ident>(name).is_ok() {
471        write!(contents, "pub mod {name};")?;
472    } else {
473        write!(contents, "pub mod r#{name};")?;
474    }
475    Ok(())
476}
477
478/// Qualifies paths to sibling binding modules when a generated item in the current module shadows
479/// that module name.
480///
481/// Alloy names the event enum for a contract module by appending `Events` to the contract name. If
482/// the ABI also contains a sibling contract/interface with that exact name, inherited event
483/// parameter types such as `IExampleContractEvents::SomeEventData` resolve to the local event enum
484/// instead of the sibling module that owns `SomeEventData`. Qualifying those paths with `super::`
485/// keeps the generated binding compiling without changing the upstream `sol!` expansion.
486fn qualify_shadowed_sibling_module_paths(mut contents: String) -> String {
487    let module_names = top_level_module_names(&contents);
488    let enum_names = public_enum_names(&contents);
489
490    for module_name in module_names {
491        if enum_names.iter().any(|enum_name| enum_name == &module_name) {
492            contents = qualify_unqualified_module_paths(&contents, &module_name);
493        }
494    }
495
496    contents
497}
498
499fn qualify_unqualified_module_paths(contents: &str, module_name: &str) -> String {
500    let needle = format!("{module_name}::");
501    let replacement = format!("super::{module_name}::");
502    let mut qualified = String::with_capacity(contents.len());
503    let mut rest = contents;
504
505    while let Some(index) = rest.find(&needle) {
506        let (before, after) = rest.split_at(index);
507        qualified.push_str(before);
508
509        let boundary = before
510            .chars()
511            .next_back()
512            .is_none_or(|c| !matches!(c, '_' | '0'..='9' | 'a'..='z' | 'A'..='Z' | ':'));
513
514        if boundary {
515            qualified.push_str(&replacement);
516        } else {
517            qualified.push_str(&needle);
518        }
519
520        rest = &after[needle.len()..];
521    }
522
523    qualified.push_str(rest);
524    qualified
525}
526
527fn top_level_module_names(contents: &str) -> Vec<String> {
528    contents
529        .split("pub mod ")
530        .skip(1)
531        .filter_map(|rest| rest.split_whitespace().next())
532        .map(|name| name.trim_start_matches("r#").to_string())
533        .collect()
534}
535
536fn public_enum_names(contents: &str) -> Vec<String> {
537    contents
538        .split("pub enum ")
539        .skip(1)
540        .filter_map(|rest| rest.split_whitespace().next())
541        .map(|name| name.trim_start_matches("r#").to_string())
542        .collect()
543}
544
545#[cfg(test)]
546mod tests {
547    use super::large_array_serde_adapter;
548
549    fn adapter(ty: &str) -> Option<String> {
550        large_array_serde_adapter(&syn::parse_str(ty).unwrap())
551    }
552
553    #[test]
554    fn builds_large_array_serde_adapters() {
555        assert_eq!(adapter("[u64; 32]"), None);
556        assert_eq!(adapter("[u64; 33]"), Some("[::serde_with::Same; 33]".to_string()));
557        assert_eq!(adapter("[[u64; 48]; 2]"), Some("[[::serde_with::Same; 48]; 2]".to_string()));
558        assert_eq!(
559            adapter("alloy::sol_types::private::Vec<[u64; 48]>"),
560            Some("::std::vec::Vec<[::serde_with::Same; 48]>".to_string())
561        );
562    }
563}
forge_sol_macro_gen/sol_macro_gen.rs

forge_sol_macro_gen/
sol_macro_gen.rs
