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_json_abi::ToSolConfig;
13use alloy_sol_macro_expander::expand::expand;
14use alloy_sol_macro_input::{SolInput, SolInputKind};
15use eyre::{Context, OptionExt, Result};
16use foundry_common::fs;
17use proc_macro2::{Span, TokenStream};
18use rayon::prelude::*;
19use std::{
20    fmt::Write,
21    io::{BufWriter, Write as IoWrite},
22    path::{Path, PathBuf},
23};
24
25use heck::ToSnakeCase;
26
27const SERDE_ARRAY_IMPL_MAX_LEN: usize = 32;
28const SERDE_WITH_DEP: &str =
29    r#"serde_with = { version = "3.15", default-features = false, features = ["std"] }"#;
30const BINDINGS_HEADER: &str = r#"#![allow(unused_imports, unused_attributes, clippy::all, rustdoc::all)]
31//! This module contains the sol! generated bindings for solidity contracts.
32//! This is autogenerated code.
33//! Do not manually edit these files.
34//! These files may be overwritten by the codegen system at any time.
35"#;
36
37pub struct SolMacroGen {
38    pub path: PathBuf,
39    pub name: String,
40    pub expansion: Option<String>,
41    needs_serde_with: bool,
42}
43
44impl SolMacroGen {
45    pub const fn new(path: PathBuf, name: String) -> Self {
46        Self { path, name, expansion: None, needs_serde_with: false }
47    }
48
49    pub fn get_sol_input(&self) -> Result<SolInput> {
50        let path = self.path.to_string_lossy().into_owned();
51        let name: syn::Ident = syn::parse_str(&self.name).wrap_err_with(|| {
52            format!("`{}` is not a valid Rust identifier for generated bindings", self.name)
53        })?;
54        let tokens = quote::quote! {
55            #[sol(ignore_unlinked)]
56            #name,
57            #path
58        };
59
60        let sol_input: SolInput = syn::parse2(tokens).wrap_err("failed to parse input")?;
61
62        Ok(sol_input)
63    }
64}
65
66pub struct MultiSolMacroGen {
67    pub instances: Vec<SolMacroGen>,
68}
69
70impl MultiSolMacroGen {
71    pub const fn new(instances: Vec<SolMacroGen>) -> Self {
72        Self { instances }
73    }
74
75    pub fn populate_expansion(&mut self, bindings_path: &Path) -> Result<()> {
76        for instance in &mut self.instances {
77            let path = bindings_path.join(format!("{}.rs", instance.name.to_snake_case()));
78            let expansion = fs::read_to_string(path).wrap_err("Failed to read file")?;
79            expansion
80                .parse::<TokenStream>()
81                .map_err(|e| eyre::eyre!("Failed to parse TokenStream: {e}"))?;
82            instance.expansion = Some(expansion);
83        }
84        Ok(())
85    }
86
87    pub fn generate_bindings(&mut self, all_derives: bool, sol_config: &ToSolConfig) -> Result<()> {
88        self.instances.par_iter_mut().try_for_each(|instance| {
89            Self::generate_binding(instance, all_derives, sol_config).wrap_err_with(|| {
90                format!(
91                    "failed to generate bindings for {}:{}",
92                    instance.path.display(),
93                    instance.name
94                )
95            })
96        })
97    }
98
99    fn generate_binding(
100        instance: &mut SolMacroGen,
101        all_derives: bool,
102        sol_config: &ToSolConfig,
103    ) -> Result<()> {
104        let input = instance.get_sol_input()?.normalize_json_with_config(sol_config.clone())?;
105        let SolInput { attrs: _, path: _, kind } = input;
106
107        let tokens = match kind {
108            SolInputKind::Sol(mut file) => {
109                let sol_attr: syn::Attribute = if all_derives {
110                    syn::parse_quote! {
111                            #[sol(rpc, alloy_sol_types = alloy::sol_types, alloy_contract =
112                    alloy::contract, all_derives = true, extra_derives(serde::Serialize,
113                    serde::Deserialize))]     }
114                } else {
115                    syn::parse_quote! {
116                            #[sol(rpc, alloy_sol_types = alloy::sol_types, alloy_contract =
117                    alloy::contract)]     }
118                };
119                file.attrs.push(sol_attr);
120                expand(file).wrap_err("failed to expand")?
121            }
122            _ => unreachable!(),
123        };
124
125        let (tokens, needs_serde_with) =
126            if all_derives { add_large_array_serde_attrs(tokens)? } else { (tokens, false) };
127
128        let file = syn::parse2(tokens).wrap_err("failed to parse generated tokens as an AST")?;
129        instance.expansion =
130            Some(qualify_shadowed_sibling_module_paths(prettyplease::unparse(&file)));
131        instance.needs_serde_with = needs_serde_with;
132        Ok(())
133    }
134
135    #[allow(clippy::too_many_arguments)]
136    pub fn write_to_crate(
137        &mut self,
138        name: &str,
139        version: &str,
140        description: &str,
141        license: &str,
142        bindings_path: &Path,
143        single_file: bool,
144        alloy_version: Option<String>,
145        alloy_rev: Option<String>,
146        all_derives: bool,
147        sol_config: &ToSolConfig,
148    ) -> Result<()> {
149        self.generate_bindings(all_derives, sol_config)?;
150
151        let src = bindings_path.join("src");
152        fs::create_dir_all(&src)?;
153
154        // Write Cargo.toml
155        let cargo_toml_path = bindings_path.join("Cargo.toml");
156        let mut toml_contents = format!(
157            r#"[package]
158name = "{name}"
159version = "{version}"
160edition = "2021"
161"#
162        );
163
164        if !description.is_empty() {
165            toml_contents.push_str(&format!("description = \"{description}\"\n"));
166        }
167
168        if !license.is_empty() {
169            let formatted_licenses: Vec<String> =
170                license.split(',').map(Self::parse_license_alias).collect();
171
172            let formatted_license = formatted_licenses.join(" OR ");
173            toml_contents.push_str(&format!("license = \"{formatted_license}\"\n"));
174        }
175
176        toml_contents.push_str("\n[dependencies]\n");
177
178        let alloy_dep = Self::get_alloy_dep(alloy_version, alloy_rev);
179        write!(toml_contents, "{alloy_dep}")?;
180
181        if all_derives {
182            let serde_dep = r#"serde = { version = "1.0", features = ["derive"] }"#;
183            write!(toml_contents, "\n{serde_dep}")?;
184            if self.instances.iter().any(|instance| instance.needs_serde_with) {
185                write!(toml_contents, "\n{SERDE_WITH_DEP}")?;
186            }
187        }
188
189        fs::write(cargo_toml_path, toml_contents).wrap_err("Failed to write Cargo.toml")?;
190
191        let lib_path = src.join("lib.rs");
192        if single_file {
193            write_single_file(&lib_path, &self.instances).wrap_err("Failed to write lib.rs")?;
194            return Ok(());
195        }
196
197        let mut lib_contents = BINDINGS_HEADER.to_string();
198        for instance in &self.instances {
199            let contents = instance.expansion.as_ref().unwrap();
200            let name = instance.name.to_snake_case();
201            let path = src.join(format!("{name}.rs"));
202            fs::write(path, contents).wrap_err("failed to write to file")?;
203            write_mod_name(&mut lib_contents, &name)?;
204        }
205
206        let lib_file = syn::parse_file(&lib_contents).wrap_err(
207            "failed to parse generated tokens as an AST for lib.rs;\nthis is likely a bug",
208        )?;
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        sol_config: &ToSolConfig,
238    ) -> Result<()> {
239        self.generate_bindings(all_derives, sol_config)?;
240
241        fs::create_dir_all(bindings_path)?;
242
243        let mod_path = bindings_path.join("mod.rs");
244        if single_file {
245            write_single_file(&mod_path, &self.instances).wrap_err("Failed to write mod.rs")?;
246            return Ok(());
247        }
248
249        let mut mod_contents = BINDINGS_HEADER.to_string();
250        for instance in &self.instances {
251            let name = instance.name.to_snake_case();
252            write_mod_name(&mut mod_contents, &name)?;
253            fs::write(
254                bindings_path.join(format!("{name}.rs")),
255                instance.expansion.as_ref().unwrap(),
256            )
257            .wrap_err("Failed to write file")?;
258        }
259
260        let mod_file = syn::parse_file(&mod_contents)?;
261        let mod_contents = qualify_shadowed_sibling_module_paths(prettyplease::unparse(&mod_file));
262
263        fs::write(mod_path, mod_contents).wrap_err("Failed to write mod.rs")?;
264
265        Ok(())
266    }
267
268    /// Checks that the generated bindings are up to date with the latest version of
269    /// `sol!`.
270    ///
271    /// Returns `Ok(())` if the generated bindings are up to date, otherwise it returns
272    /// `Err(_)`.
273    #[expect(clippy::too_many_arguments)]
274    pub fn check_consistency(
275        &self,
276        name: &str,
277        version: &str,
278        crate_path: &Path,
279        single_file: bool,
280        check_cargo_toml: bool,
281        is_mod: bool,
282        alloy_version: Option<String>,
283        alloy_rev: Option<String>,
284    ) -> Result<()> {
285        if check_cargo_toml && !is_mod {
286            self.check_cargo_toml(name, version, crate_path, alloy_version, alloy_rev)?;
287        }
288
289        let mut super_contents = BINDINGS_HEADER.to_string();
290        if single_file {
291            for instance in &self.instances {
292                let contents = instance
293                    .expansion
294                    .as_ref()
295                    .ok_or_eyre(format!("TokenStream for {} does not exist", instance.name))?;
296                super_contents.push_str(contents);
297            }
298        } else {
299            for instance in &self.instances {
300                let name = instance.name.to_snake_case();
301                let path = if is_mod {
302                    crate_path.join(format!("{name}.rs"))
303                } else {
304                    crate_path.join(format!("src/{name}.rs"))
305                };
306                let contents = instance
307                    .expansion
308                    .as_ref()
309                    .ok_or_eyre(format!("TokenStream for {path:?} does not exist"))?;
310
311                self.check_file_contents(&path, contents)?;
312                write_mod_name(&mut super_contents, &name)?;
313            }
314        }
315
316        let super_path =
317            if is_mod { crate_path.join("mod.rs") } else { crate_path.join("src/lib.rs") };
318        self.check_file_contents(&super_path, &super_contents)?;
319
320        Ok(())
321    }
322
323    fn check_file_contents(&self, file_path: &Path, expected_contents: &str) -> Result<()> {
324        eyre::ensure!(file_path.is_file(), "{} is not a file", file_path.display());
325        let file_contents = fs::read_to_string(file_path).wrap_err("Failed to read file")?;
326
327        // Untouched bindings match byte for byte, so only reparse edited or stale files.
328        if file_contents == expected_contents {
329            return Ok(());
330        }
331
332        // Only normalize formatting: generated expansions already have qualified paths.
333        // Format one side at a time so that only one syntax tree is alive.
334        let formatted_file = prettyplease::unparse(&syn::parse_file(&file_contents)?);
335        let formatted_exp = prettyplease::unparse(&syn::parse_file(expected_contents)?);
336
337        eyre::ensure!(
338            formatted_file == formatted_exp,
339            "File contents do not match expected contents for \"{}\"",
340            file_path.display()
341        );
342        Ok(())
343    }
344
345    fn check_cargo_toml(
346        &self,
347        name: &str,
348        version: &str,
349        crate_path: &Path,
350        alloy_version: Option<String>,
351        alloy_rev: Option<String>,
352    ) -> Result<()> {
353        eyre::ensure!(crate_path.is_dir(), "Crate path must be a directory");
354
355        let cargo_toml_path = crate_path.join("Cargo.toml");
356
357        eyre::ensure!(cargo_toml_path.is_file(), "Cargo.toml must exist");
358        let cargo_toml_contents =
359            fs::read_to_string(cargo_toml_path).wrap_err("Failed to read Cargo.toml")?;
360
361        let name_check = format!("name = \"{name}\"");
362        let version_check = format!("version = \"{version}\"");
363        let alloy_dep_check = Self::get_alloy_dep(alloy_version, alloy_rev);
364        let serde_with_consistent =
365            !self.instances.iter().any(|instance| instance.needs_serde_with)
366                || cargo_toml_contents.contains(SERDE_WITH_DEP);
367        let toml_consistent = cargo_toml_contents.contains(&name_check)
368            && cargo_toml_contents.contains(&version_check)
369            && cargo_toml_contents.contains(&alloy_dep_check)
370            && serde_with_consistent;
371        eyre::ensure!(
372            toml_consistent,
373            r#"The contents of Cargo.toml do not match the expected output of the latest `sol!` version.
374                This indicates that the existing bindings are outdated and need to be generated again."#
375        );
376
377        Ok(())
378    }
379
380    /// Returns the `alloy` dependency string for the Cargo.toml file.
381    /// If `alloy_version` is provided, it will use that version from crates.io.
382    /// If `alloy_rev` is provided, it will use that revision from the GitHub repository.
383    fn get_alloy_dep(alloy_version: Option<String>, alloy_rev: Option<String>) -> String {
384        if let Some(alloy_version) = alloy_version {
385            format!(
386                r#"alloy = {{ version = "{alloy_version}", features = ["sol-types", "contract"] }}"#,
387            )
388        } else if let Some(alloy_rev) = alloy_rev {
389            format!(
390                r#"alloy = {{ git = "https://github.com/alloy-rs/alloy", rev = "{alloy_rev}", features = ["sol-types", "contract"] }}"#,
391            )
392        } else {
393            r#"alloy = { version = "1.0", features = ["sol-types", "contract"] }"#.to_string()
394        }
395    }
396}
397
398/// Writes individually validated and formatted expansions without reparsing the combined output.
399fn write_single_file(path: &Path, instances: &[SolMacroGen]) -> Result<()> {
400    let file = fs::create_file(path)?;
401    let mut writer = BufWriter::new(file);
402    writer.write_all(BINDINGS_HEADER.as_bytes())?;
403    for instance in instances {
404        writer.write_all(instance.expansion.as_ref().unwrap().as_bytes())?;
405    }
406    writer.flush()?;
407    Ok(())
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
564    #[test]
565    fn get_sol_input_rejects_invalid_identifier_instead_of_panicking() {
566        // `$` is valid in Solidity identifiers but not Rust identifiers.
567        let instance =
568            super::SolMacroGen::new(std::path::PathBuf::from("Foo.json"), "Foo$Bar".to_string());
569        assert!(instance.get_sol_input().is_err());
570    }
571}
forge_sol_macro_gen/sol_macro_gen.rs

forge_sol_macro_gen/
sol_macro_gen.rs
