From 67167be1679c60eefa2c314c5e4a2b673d5eef11 Mon Sep 17 00:00:00 2001 From: Philipp Hansch Date: Sun, 17 May 2020 18:14:43 +0200 Subject: [PATCH] Make empty_line_after_outer_attr an early lint --- clippy_lints/Cargo.toml | 4 + clippy_lints/src/attrs.rs | 75 +++++++++++-------- tests/compile-test.rs | 2 +- tests/ui/auxiliary/proc_macro_attr.rs | 37 +++++++++ tests/ui/empty_line_after_outer_attribute.rs | 19 ++++- .../empty_line_after_outer_attribute.stderr | 12 +-- 6 files changed, 109 insertions(+), 40 deletions(-) create mode 100644 tests/ui/auxiliary/proc_macro_attr.rs diff --git a/clippy_lints/Cargo.toml b/clippy_lints/Cargo.toml index 1c0be72783462..043a79f200199 100644 --- a/clippy_lints/Cargo.toml +++ b/clippy_lints/Cargo.toml @@ -33,5 +33,9 @@ semver = "0.9.0" # see url = { version = "2.1.0", features = ["serde"] } +[dev-dependencies] +quote = "*" +syn = { version = "*", features = ["full"] } + [features] deny-warnings = [] diff --git a/clippy_lints/src/attrs.rs b/clippy_lints/src/attrs.rs index 64abc9fdc7174..41f125d48398f 100644 --- a/clippy_lints/src/attrs.rs +++ b/clippy_lints/src/attrs.rs @@ -248,7 +248,6 @@ declare_lint_pass!(Attributes => [ INLINE_ALWAYS, DEPRECATED_SEMVER, USELESS_ATTRIBUTE, - EMPTY_LINE_AFTER_OUTER_ATTR, UNKNOWN_CLIPPY_LINTS, ]); @@ -480,36 +479,6 @@ fn check_attrs(cx: &LateContext<'_, '_>, span: Span, name: Name, attrs: &[Attrib } for attr in attrs { - let attr_item = if let AttrKind::Normal(ref attr) = attr.kind { - attr - } else { - continue; - }; - - if attr.style == AttrStyle::Outer { - if attr_item.args.inner_tokens().is_empty() || !is_present_in_source(cx, attr.span) { - return; - } - - let begin_of_attr_to_item = Span::new(attr.span.lo(), span.lo(), span.ctxt()); - let end_of_attr_to_item = Span::new(attr.span.hi(), span.lo(), span.ctxt()); - - if let Some(snippet) = snippet_opt(cx, end_of_attr_to_item) { - let lines = snippet.split('\n').collect::>(); - let lines = without_block_comments(lines); - - if lines.iter().filter(|l| l.trim().is_empty()).count() > 2 { - span_lint( - cx, - EMPTY_LINE_AFTER_OUTER_ATTR, - begin_of_attr_to_item, - "Found an empty line after an outer attribute. \ - Perhaps you forgot to add a `!` to make it an inner attribute?", - ); - } - } - } - if let Some(values) = attr.meta_item_list() { if values.len() != 1 || !attr.check_name(sym!(inline)) { continue; @@ -551,15 +520,57 @@ fn is_word(nmi: &NestedMetaItem, expected: Symbol) -> bool { } } -declare_lint_pass!(EarlyAttributes => [DEPRECATED_CFG_ATTR, MISMATCHED_TARGET_OS]); +declare_lint_pass!(EarlyAttributes => [ + DEPRECATED_CFG_ATTR, + MISMATCHED_TARGET_OS, + EMPTY_LINE_AFTER_OUTER_ATTR, +]); impl EarlyLintPass for EarlyAttributes { + fn check_item(&mut self, cx: &EarlyContext<'_>, item: &rustc_ast::ast::Item) { + check_empty_line_after_outer_attr(cx, item); + } + fn check_attribute(&mut self, cx: &EarlyContext<'_>, attr: &Attribute) { check_deprecated_cfg_attr(cx, attr); check_mismatched_target_os(cx, attr); } } +fn check_empty_line_after_outer_attr(cx: &EarlyContext<'_>, item: &rustc_ast::ast::Item) { + for attr in &item.attrs { + let attr_item = if let AttrKind::Normal(ref attr) = attr.kind { + attr + } else { + return; + }; + + if attr.style == AttrStyle::Outer { + if attr_item.args.inner_tokens().is_empty() || !is_present_in_source(cx, attr.span) { + return; + } + + let begin_of_attr_to_item = Span::new(attr.span.lo(), item.span.lo(), item.span.ctxt()); + let end_of_attr_to_item = Span::new(attr.span.hi(), item.span.lo(), item.span.ctxt()); + + if let Some(snippet) = snippet_opt(cx, end_of_attr_to_item) { + let lines = snippet.split('\n').collect::>(); + let lines = without_block_comments(lines); + + if lines.iter().filter(|l| l.trim().is_empty()).count() > 2 { + span_lint( + cx, + EMPTY_LINE_AFTER_OUTER_ATTR, + begin_of_attr_to_item, + "Found an empty line after an outer attribute. \ + Perhaps you forgot to add a `!` to make it an inner attribute?", + ); + } + } + } + } +} + fn check_deprecated_cfg_attr(cx: &EarlyContext<'_>, attr: &Attribute) { if_chain! { // check cfg_attr diff --git a/tests/compile-test.rs b/tests/compile-test.rs index a5de84293909f..2758b9a7e7604 100644 --- a/tests/compile-test.rs +++ b/tests/compile-test.rs @@ -38,7 +38,7 @@ fn clippy_driver_path() -> PathBuf { // as what we manually pass to `cargo` invocation fn third_party_crates() -> String { use std::collections::HashMap; - static CRATES: &[&str] = &["serde", "serde_derive", "regex", "clippy_lints"]; + static CRATES: &[&str] = &["serde", "serde_derive", "regex", "clippy_lints", "syn", "quote"]; let dep_dir = cargo::TARGET_LIB.join("deps"); let mut crates: HashMap<&str, PathBuf> = HashMap::with_capacity(CRATES.len()); for entry in fs::read_dir(dep_dir).unwrap() { diff --git a/tests/ui/auxiliary/proc_macro_attr.rs b/tests/ui/auxiliary/proc_macro_attr.rs new file mode 100644 index 0000000000000..e6626d57a7722 --- /dev/null +++ b/tests/ui/auxiliary/proc_macro_attr.rs @@ -0,0 +1,37 @@ +// no-prefer-dynamic + +#![crate_type = "proc-macro"] +#![feature(repr128, proc_macro_hygiene, proc_macro_quote)] +#![allow(clippy::useless_conversion)] + +extern crate proc_macro; +extern crate quote; +extern crate syn; + +use proc_macro::TokenStream; +use quote::{quote, quote_spanned}; +use syn::parse_macro_input; +use syn::{parse_quote, ItemTrait, TraitItem}; + +#[proc_macro_attribute] +pub fn fake_async_trait(_args: TokenStream, input: TokenStream) -> TokenStream { + let mut item = parse_macro_input!(input as ItemTrait); + for inner in &mut item.items { + if let TraitItem::Method(method) = inner { + let sig = &method.sig; + let block = &mut method.default; + if let Some(block) = block { + let brace = block.brace_token; + + let my_block = quote_spanned!( brace.span => { + // Should not trigger `empty_line_after_outer_attr` + #[crate_type = "lib"] + #sig #block + Vec::new() + }); + *block = parse_quote!(#my_block); + } + } + } + TokenStream::from(quote!(#item)) +} diff --git a/tests/ui/empty_line_after_outer_attribute.rs b/tests/ui/empty_line_after_outer_attribute.rs index 5343dff9da1db..3e92bca986ab5 100644 --- a/tests/ui/empty_line_after_outer_attribute.rs +++ b/tests/ui/empty_line_after_outer_attribute.rs @@ -1,8 +1,12 @@ +// aux-build:proc_macro_attr.rs #![warn(clippy::empty_line_after_outer_attr)] #![allow(clippy::assertions_on_constants)] #![feature(custom_inner_attributes)] #![rustfmt::skip] +#[macro_use] +extern crate proc_macro_attr; + // This should produce a warning #[crate_type = "lib"] @@ -93,4 +97,17 @@ pub struct S; /* test */ pub struct T; -fn main() { } +// This should not produce a warning +// See https://github.com/rust-lang/rust-clippy/issues/5567 +#[fake_async_trait] +pub trait Bazz { + fn foo() -> Vec { + let _i = ""; + + + + vec![] + } +} + +fn main() {} diff --git a/tests/ui/empty_line_after_outer_attribute.stderr b/tests/ui/empty_line_after_outer_attribute.stderr index d8c9786541f0b..bf753a732f000 100644 --- a/tests/ui/empty_line_after_outer_attribute.stderr +++ b/tests/ui/empty_line_after_outer_attribute.stderr @@ -1,5 +1,5 @@ error: Found an empty line after an outer attribute. Perhaps you forgot to add a `!` to make it an inner attribute? - --> $DIR/empty_line_after_outer_attribute.rs:7:1 + --> $DIR/empty_line_after_outer_attribute.rs:11:1 | LL | / #[crate_type = "lib"] LL | | @@ -10,7 +10,7 @@ LL | | fn with_one_newline_and_comment() { assert!(true) } = note: `-D clippy::empty-line-after-outer-attr` implied by `-D warnings` error: Found an empty line after an outer attribute. Perhaps you forgot to add a `!` to make it an inner attribute? - --> $DIR/empty_line_after_outer_attribute.rs:19:1 + --> $DIR/empty_line_after_outer_attribute.rs:23:1 | LL | / #[crate_type = "lib"] LL | | @@ -18,7 +18,7 @@ LL | | fn with_one_newline() { assert!(true) } | |_ error: Found an empty line after an outer attribute. Perhaps you forgot to add a `!` to make it an inner attribute? - --> $DIR/empty_line_after_outer_attribute.rs:24:1 + --> $DIR/empty_line_after_outer_attribute.rs:28:1 | LL | / #[crate_type = "lib"] LL | | @@ -27,7 +27,7 @@ LL | | fn with_two_newlines() { assert!(true) } | |_ error: Found an empty line after an outer attribute. Perhaps you forgot to add a `!` to make it an inner attribute? - --> $DIR/empty_line_after_outer_attribute.rs:31:1 + --> $DIR/empty_line_after_outer_attribute.rs:35:1 | LL | / #[crate_type = "lib"] LL | | @@ -35,7 +35,7 @@ LL | | enum Baz { | |_ error: Found an empty line after an outer attribute. Perhaps you forgot to add a `!` to make it an inner attribute? - --> $DIR/empty_line_after_outer_attribute.rs:39:1 + --> $DIR/empty_line_after_outer_attribute.rs:43:1 | LL | / #[crate_type = "lib"] LL | | @@ -43,7 +43,7 @@ LL | | struct Foo { | |_ error: Found an empty line after an outer attribute. Perhaps you forgot to add a `!` to make it an inner attribute? - --> $DIR/empty_line_after_outer_attribute.rs:47:1 + --> $DIR/empty_line_after_outer_attribute.rs:51:1 | LL | / #[crate_type = "lib"] LL | |