Skip to content

Commit

Permalink
add updated lint rules for s! macros
Browse files Browse the repository at this point in the history
  • Loading branch information
@rmehri01
rmehri01 committed Jan 9, 2025
1 parent e13e036 commit 60c840e
Show file tree
Hide file tree
Showing 2 changed files with 201 additions and 51 deletions.
111 changes: 79 additions & 32 deletions libc-test/test/style/mod.rs
View file
Original file line number Diff line number Diff line change
Expand Up @@ -17,10 +17,15 @@
//! 5. f! { ... } functions
//! 6. extern functions
//! 7. modules + pub use
//! * Use cfg_if! over #[cfg(...)]
//! * No manual deriving Copy/Clone
//! * Only one f! per module
//! * Multiple s! macros are allowed as long as there isn't a duplicate cfg,
//! whether as a standalone attribute (#[cfg]) or in a cfg_if!
//! * s! macros should not just have a positive cfg since they should
//! just go into the relevant file but combined cfgs with all(...) and
//! any(...) are allowed
use std::collections::HashMap;
use std::fs;
use std::ops::Deref;
use std::path::{Path, PathBuf};
Expand All @@ -42,8 +47,7 @@ pub struct StyleChecker {
/// Span of the first item encountered in this state to use in help
/// diagnostic text.
state_span: Option<Span>,
// FIXME: see StyleChecker::set_state
_s_macros: usize,
seen_s_macro_cfgs: HashMap<String, Span>,
/// Span of the first f! macro seen, used to enforce only one f! macro
/// per module.
first_f_macro: Option<Span>,
Expand Down Expand Up @@ -167,13 +171,6 @@ impl StyleChecker {
);
}

// FIXME(#4109): multiple should be allowed if at least one is `cfg(not) within `cfg_if`.
// For now just disable this and check by hand.
// if self.s_macros == 2 {
// self.s_macros += 1;
// (self.on_err)(line, "multiple s! macros in one module");
// }

if self.state != new_state {
self.state = new_state;
self.state_span = Some(span);
Expand All @@ -182,22 +179,22 @@ impl StyleChecker {

/// Visit the items inside the [ExprCfgIf], restoring the state after
/// each branch.
fn visit_cfg_expr_if(&mut self, cfg_expr_if: &ExprCfgIf) {
fn visit_expr_cfg_if(&mut self, expr_cfg_if: &ExprCfgIf) {
let initial_state = self.state;

for item in &cfg_expr_if.then_branch {
for item in &expr_cfg_if.then_branch {
self.visit_item(item);
}
self.state = initial_state;

if let Some(else_branch) = &cfg_expr_if.else_branch {
if let Some(else_branch) = &expr_cfg_if.else_branch {
match else_branch.deref() {
ExprCfgElse::Block(items) => {
for item in items {
self.visit_item(item);
}
}
ExprCfgElse::If(cfg_expr_if) => self.visit_cfg_expr_if(&cfg_expr_if),
ExprCfgElse::If(expr_cfg_if) => self.visit_expr_cfg_if(&expr_cfg_if),
}
}
self.state = initial_state;
Expand All @@ -222,19 +219,7 @@ impl<'ast> Visit<'ast> for StyleChecker {
fn visit_meta_list(&mut self, meta_list: &'ast syn::MetaList) {
let span = meta_list.span();
let meta_str = meta_list.tokens.to_string();
if meta_list.path.is_ident("cfg")
&& !(meta_str.contains("target_endian") || meta_str.contains("target_arch"))
{
self.error(
"cfg_if! over #[cfg]".to_string(),
span,
String::new(),
(
None,
"use cfg_if! and submodules instead of #[cfg]".to_string(),
),
);
} else if meta_list.path.is_ident("derive")
if meta_list.path.is_ident("derive")
&& (meta_str.contains("Copy") || meta_str.contains("Clone"))
{
self.error(
Expand Down Expand Up @@ -287,18 +272,76 @@ impl<'ast> Visit<'ast> for StyleChecker {
visit::visit_item_type(self, item_type);
}

fn visit_item_macro(&mut self, item_macro: &'ast syn::ItemMacro) {
if item_macro.mac.path.is_ident("s") {
if item_macro.attrs.is_empty() {
let span = item_macro.span();
match self.seen_s_macro_cfgs.get("") {
Some(seen_span) => {
self.error(
"duplicate s! macro".to_string(),
span,
format!("other s! macro"),
(Some(*seen_span), "combine the two".to_string()),
);
}
None => {
self.seen_s_macro_cfgs.insert(String::new(), span);
}
}
} else {
for attr in &item_macro.attrs {
if let Ok(meta_list) = attr.meta.require_list() {
if meta_list.path.is_ident("cfg") {
let span = meta_list.span();
let meta_str = meta_list.tokens.to_string();

match self.seen_s_macro_cfgs.get(&meta_str) {
Some(seen_span) => {
self.error(
"duplicate #[cfg] for s! macro".to_string(),
span,
"duplicated #[cfg]".to_string(),
(Some(*seen_span), "combine the two".to_string()),
);
}
None => {
self.seen_s_macro_cfgs.insert(meta_str.clone(), span);
}
}

if !meta_str.starts_with("not")
&& !meta_str.starts_with("any")
&& !meta_str.starts_with("all")
{
self.error(
"positive #[cfg] for s! macro".to_string(),
span,
String::new(),
(None, "move it to the relevant file".to_string()),
);
}
}
}
}
}
}

visit::visit_item_macro(self, item_macro);
}

fn visit_macro(&mut self, mac: &'ast syn::Macro) {
let span = mac.span();
if mac.path.is_ident("cfg_if") {
let cfg_expr_if: ExprCfgIf = mac
let expr_cfg_if: ExprCfgIf = mac
.parse_body()
.expect("cfg_if! should be parsed since it compiled");

self.visit_cfg_expr_if(&cfg_expr_if);
self.visit_expr_cfg_if(&expr_cfg_if);
} else {
let new_state = if mac.path.is_ident("s") {
// FIXME: see StyleChecker::set_state
// self.s_macros += 1;
// multiple macros are allowed if they have proper #[cfg(...)]
// attributes, see Self::visit_item_macro
State::Structs
} else if mac.path.is_ident("s_no_extra_traits") {
// multiple macros of this type are allowed
Expand Down Expand Up @@ -362,7 +405,11 @@ impl Parse for ExprCfgIf {
let then_branch: Vec<syn::Item> = {
let mut items = Vec::new();
while !content.is_empty() {
items.push(content.parse()?);
let mut value = content.parse()?;
if let syn::Item::Macro(item_macro) = &mut value {
item_macro.attrs.push(attr.clone());
}
items.push(value);
}
items
};
Expand Down
Loading

0 comments on commit 60c840e

Please sign in to comment.