Merge pull request #2777 from rust-lang-nursery/scoped_attrs

Use the new scoped tool attributes

Author: oli-obk

CONTRIBUTING.md

@@ -80,12 +80,8 @@ First, create a new UI test file in the `tests/ui/` directory with the pattern y
 
 ```rust
 // ./tests/ui/my_lint.rs
-
-// The custom_attribute needs to be enabled for the author lint to work
-#![feature(plugin, custom_attribute)]
-
 fn main() {
-    #[clippy(author)]
+    #[clippy::author]
     let arr: [i32; 1] = [7]; // Replace line with the code you want to match
 }
 ```

clippy_lints/src/lib.rs

@@ -1,7 +1,6 @@
 // error-pattern:cargo-clippy
 
 #![feature(box_syntax)]
-#![feature(custom_attribute)]
 #![feature(rustc_private)]
 #![feature(slice_patterns)]
 #![feature(stmt_expr_attributes)]

clippy_lints/src/utils/author.rs

@@ -7,8 +7,9 @@ use rustc::lint::*;
 use rustc::hir;
 use rustc::hir::{Expr, Expr_, QPath, Ty_, Pat, PatKind, BindingAnnotation, StmtSemi, StmtExpr, StmtDecl, Decl_, Stmt};
 use rustc::hir::intravisit::{NestedVisitorMap, Visitor};
-use syntax::ast::{self, Attribute, LitKind, DUMMY_NODE_ID};
+use syntax::ast::{Attribute, LitKind, DUMMY_NODE_ID};
 use std::collections::HashMap;
+use utils::get_attr;
 
 /// **What it does:** Generates clippy code that detects the offending pattern
 ///
@@ -17,10 +18,10 @@ use std::collections::HashMap;
 /// // ./tests/ui/my_lint.rs
 /// fn foo() {
 ///     // detect the following pattern
-///     #[clippy(author)]
+///     #[clippy::author]
 ///     if x == 42 {
 ///         // but ignore everything from here on
-///         #![clippy(author = "ignore")]
+///         #![clippy::author = "ignore"]
 ///     }
 /// }
 /// ```
@@ -633,14 +634,7 @@ impl<'tcx> Visitor<'tcx> for PrintVisitor {
 }
 
 fn has_attr(attrs: &[Attribute]) -> bool {
-    attrs.iter().any(|attr| {
-        attr.check_name("clippy") && attr.meta_item_list().map_or(false, |list| {
-            list.len() == 1 && match list[0].node {
-                ast::NestedMetaItemKind::MetaItem(ref it) => it.name() == "author",
-                ast::NestedMetaItemKind::Literal(_) => false,
-            }
-        })
-    })
+    get_attr(attrs, "author").count() > 0
 }
 
 fn desugaring_name(des: hir::MatchSource) -> String {

clippy_lints/src/utils/inspector.rs

@@ -6,7 +6,7 @@ use rustc::lint::*;
 use rustc::hir;
 use rustc::hir::print;
 use syntax::ast::Attribute;
-use syntax::attr;
+use utils::get_attr;
 
 /// **What it does:** Dumps every ast/hir node which has the `#[clippy_dump]`
 /// attribute
@@ -136,7 +136,7 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for Pass {
 }
 
 fn has_attr(attrs: &[Attribute]) -> bool {
-    attr::contains_name(attrs, "clippy_dump")
+    get_attr(attrs, "dump").count() > 0
 }
 
 fn print_decl(cx: &LateContext, decl: &hir::Decl) {

clippy_lints/src/utils/mod.rs

@@ -735,20 +735,26 @@ impl LimitStack {
     }
 }
 
-fn parse_attrs<F: FnMut(u64)>(sess: &Session, attrs: &[ast::Attribute], name: &'static str, mut f: F) {
-    for attr in attrs {
-        if attr.is_sugared_doc {
-            continue;
+pub fn get_attr<'a>(attrs: &'a [ast::Attribute], name: &'static str) -> impl Iterator<Item = &'a ast::Attribute> {
+    attrs.iter().filter_map(move |attr| {
+        if attr.path.segments.len() == 2 && attr.path.segments[0].ident.to_string() == "clippy" && attr.path.segments[1].ident.to_string() == name {
+            Some(attr)
+        } else {
+            None
         }
+    })
+}
+
+fn parse_attrs<F: FnMut(u64)>(sess: &Session, attrs: &[ast::Attribute], name: &'static str, mut f: F) {
+    for attr in get_attr(attrs, name) {
         if let Some(ref value) = attr.value_str() {
-            if attr.name() == name {
-                if let Ok(value) = FromStr::from_str(&value.as_str()) {
-                    attr::mark_used(attr);
-                    f(value)
-                } else {
-                    sess.span_err(attr.span, "not a number");
-                }
+            if let Ok(value) = FromStr::from_str(&value.as_str()) {
+                f(value)
+            } else {
+                sess.span_err(attr.span, "not a number");
             }
+        } else {
+            sess.span_err(attr.span, "bad clippy attribute");
         }
     }
 }

tests/ui/author.rs

@@ -1,7 +1,7 @@
-#![feature(plugin, custom_attribute)]
+#![feature(tool_attributes)]
 
 fn main() {
 
-    #[clippy(author)]
+    #[clippy::author]
     let x: char = 0x45 as char;
 }

tests/ui/author/for_loop.rs

@@ -1,7 +1,7 @@
-#![feature(custom_attribute)]
+#![feature(tool_attributes)]
 
 fn main() {
-    #[clippy(author)]
+    #[clippy::author]
     for y in 0..10 {
         let z = y;
     }

tests/ui/author/matches.rs

@@ -1,7 +1,7 @@
-#![feature(custom_attribute)]
+#![feature(tool_attributes)]
 
 fn main() {
-    #[clippy(author)]
+    #[clippy::author]
     let a = match 42 {
         16 => 5,
         17 => {

tests/ui/cyclomatic_complexity.rs

@@ -1,4 +1,4 @@
-#![feature(custom_attribute)]
+#![feature(tool_attributes)]
 
 #![allow(clippy)]
 #![warn(cyclomatic_complexity)]
@@ -88,7 +88,7 @@ fn main() {
     }
 }
 
-#[cyclomatic_complexity = "0"]
+#[clippy::cyclomatic_complexity = "0"]
 fn kaboom() {
     let n = 0;
     'a: for i in 0..20 {
@@ -134,17 +134,17 @@ fn bloo() {
     }
 }
 
-#[cyclomatic_complexity = "0"]
+#[clippy::cyclomatic_complexity = "0"]
 fn lots_of_short_circuits() -> bool {
     true && false && true && false && true && false && true
 }
 
-#[cyclomatic_complexity = "0"]
+#[clippy::cyclomatic_complexity = "0"]
 fn lots_of_short_circuits2() -> bool {
     true || false || true || false || true || false || true
 }
 
-#[cyclomatic_complexity = "0"]
+#[clippy::cyclomatic_complexity = "0"]
 fn baa() {
     let x = || match 99 {
         0 => 0,
@@ -162,7 +162,7 @@ fn baa() {
     }
 }
 
-#[cyclomatic_complexity = "0"]
+#[clippy::cyclomatic_complexity = "0"]
 fn bar() {
     match 99 {
         0 => println!("hi"),
@@ -171,7 +171,7 @@ fn bar() {
 }
 
 #[test]
-#[cyclomatic_complexity = "0"]
+#[clippy::cyclomatic_complexity = "0"]
 /// Tests are usually complex but simple at the same time. `cyclomatic_complexity` used to give
 /// lots of false-positives in tests.
 fn dont_warn_on_tests() {
@@ -181,7 +181,7 @@ fn dont_warn_on_tests() {
     }
 }
 
-#[cyclomatic_complexity = "0"]
+#[clippy::cyclomatic_complexity = "0"]
 fn barr() {
     match 99 {
         0 => println!("hi"),
@@ -191,7 +191,7 @@ fn barr() {
     }
 }
 
-#[cyclomatic_complexity = "0"]
+#[clippy::cyclomatic_complexity = "0"]
 fn barr2() {
     match 99 {
         0 => println!("hi"),
@@ -207,7 +207,7 @@ fn barr2() {
     }
 }
 
-#[cyclomatic_complexity = "0"]
+#[clippy::cyclomatic_complexity = "0"]
 fn barrr() {
     match 99 {
         0 => println!("hi"),
@@ -217,7 +217,7 @@ fn barrr() {
     }
 }
 
-#[cyclomatic_complexity = "0"]
+#[clippy::cyclomatic_complexity = "0"]
 fn barrr2() {
     match 99 {
         0 => println!("hi"),
@@ -233,7 +233,7 @@ fn barrr2() {
     }
 }
 
-#[cyclomatic_complexity = "0"]
+#[clippy::cyclomatic_complexity = "0"]
 fn barrrr() {
     match 99 {
         0 => println!("hi"),
@@ -243,7 +243,7 @@ fn barrrr() {
     }
 }
 
-#[cyclomatic_complexity = "0"]
+#[clippy::cyclomatic_complexity = "0"]
 fn barrrr2() {
     match 99 {
         0 => println!("hi"),
@@ -259,7 +259,7 @@ fn barrrr2() {
     }
 }
 
-#[cyclomatic_complexity = "0"]
+#[clippy::cyclomatic_complexity = "0"]
 fn cake() {
     if 4 == 5 {
         println!("yea");
@@ -270,7 +270,7 @@ fn cake() {
 }
 
 
-#[cyclomatic_complexity = "0"]
+#[clippy::cyclomatic_complexity = "0"]
 pub fn read_file(input_path: &str) -> String {
     use std::fs::File;
     use std::io::{Read, Write};
@@ -301,29 +301,29 @@ pub fn read_file(input_path: &str) -> String {
 
 enum Void {}
 
-#[cyclomatic_complexity = "0"]
+#[clippy::cyclomatic_complexity = "0"]
 fn void(void: Void) {
     if true {
         match void {
         }
     }
 }
 
-#[cyclomatic_complexity = "0"]
+#[clippy::cyclomatic_complexity = "0"]
 fn mcarton_sees_all() {
     panic!("meh");
     panic!("möh");
 }
 
-#[cyclomatic_complexity = "0"]
+#[clippy::cyclomatic_complexity = "0"]
 fn try() -> Result<i32, &'static str> {
     match 5 {
         5 => Ok(5),
         _ => return Err("bla"),
     }
 }
 
-#[cyclomatic_complexity = "0"]
+#[clippy::cyclomatic_complexity = "0"]
 fn try_again() -> Result<i32, &'static str> {
     let _ = try!(Ok(42));
     let _ = try!(Ok(43));
@@ -339,7 +339,7 @@ fn try_again() -> Result<i32, &'static str> {
     }
 }
 
-#[cyclomatic_complexity = "0"]
+#[clippy::cyclomatic_complexity = "0"]
 fn early() -> Result<i32, &'static str> {
     return Ok(5);
     return Ok(5);
@@ -352,7 +352,7 @@ fn early() -> Result<i32, &'static str> {
     return Ok(5);
 }
 
-#[cyclomatic_complexity = "0"]
+#[clippy::cyclomatic_complexity = "0"]
 fn early_ret() -> i32 {
     let a = if true { 42 } else { return 0; };
     let a = if a < 99 { 42 } else { return 0; };

tests/ui/cyclomatic_complexity_attr_used.rs

@@ -1,4 +1,4 @@
-#![feature(custom_attribute)]
+#![feature(tool_attributes)]
 
 #![warn(cyclomatic_complexity)]
 #![warn(unused)]
@@ -7,7 +7,7 @@ fn main() {
     kaboom();
 }
 
-#[cyclomatic_complexity = "0"]
+#[clippy::cyclomatic_complexity = "0"]
 fn kaboom() {
     if 42 == 43 {
         panic!();

tests/ui/excessive_precision.rs

@@ -1,4 +1,4 @@
-#![feature(custom_attribute)]
+
 #![warn(excessive_precision)]
 #![allow(print_literal)]
 

tests/ui/for_loop.rs

@@ -1,4 +1,4 @@
-#![feature(custom_attribute)]
+
 
 
 use std::collections::*;

tests/ui/trailing_zeros.rs

@@ -1,10 +1,10 @@
-#![feature(custom_attribute, stmt_expr_attributes)]
+#![feature(stmt_expr_attributes, tool_attributes)]
 
 #![allow(unused_parens)]
 
 fn main() {
     let x: i32 = 42;
-    let _ = #[clippy(author)] (x & 0b1111 == 0);  // suggest trailing_zeros
+    let _ = #[clippy::author] (x & 0b1111 == 0);  // suggest trailing_zeros
     let _ = x & 0b1_1111 == 0; // suggest trailing_zeros
     let _ = x & 0b1_1010 == 0; // do not lint
     let _ = x & 1 == 0; // do not lint

tests/ui/trailing_zeros.stderr

@@ -1,7 +1,7 @@
 error: bit mask could be simplified with a call to `trailing_zeros`
  --> $DIR/trailing_zeros.rs:7:31
   |
-7 |     let _ = #[clippy(author)] (x & 0b1111 == 0);  // suggest trailing_zeros
+7 |     let _ = #[clippy::author] (x & 0b1111 == 0);  // suggest trailing_zeros
   |                               ^^^^^^^^^^^^^^^^^ help: try: `x.trailing_zeros() >= 4`
   |
   = note: `-D verbose-bit-mask` implied by `-D warnings`