Honor lint level attributes in more places.

This extends the LintLevelBuilder to handle lint level attributes on
struct expression fields and pattern fields.

This also updates the early lints to honor lint levels on generic
parameters.

Author: ehuss

compiler/rustc_lint/src/early.rs

@@ -219,9 +219,10 @@ impl<'a, T: EarlyLintPass> ast_visit::Visitor<'a> for EarlyContextAndPass<'a, T>
     }
 
     fn visit_generic_param(&mut self, param: &'a ast::GenericParam) {
-        run_early_pass!(self, check_generic_param, param);
-        self.check_id(param.id);
-        ast_visit::walk_generic_param(self, param);
+        self.with_lint_attrs(param.id, &param.attrs, |cx| {
+            run_early_pass!(cx, check_generic_param, param);
+            ast_visit::walk_generic_param(cx, param);
+        });
     }
 
     fn visit_generics(&mut self, g: &'a ast::Generics) {

compiler/rustc_lint/src/levels.rs

@@ -761,9 +761,26 @@ impl<'tcx> intravisit::Visitor<'tcx> for LintLevelMapBuilder<'tcx> {
     }
 
     fn visit_expr(&mut self, e: &'tcx hir::Expr<'tcx>) {
-        self.with_lint_attrs(e.hir_id, |builder| {
-            intravisit::walk_expr(builder, e);
-        })
+        match e.kind {
+            hir::ExprKind::Struct(qpath, fields, base_expr) => {
+                self.with_lint_attrs(e.hir_id, |builder| {
+                    builder.visit_qpath(qpath, e.hir_id, e.span);
+                    for field in fields {
+                        builder.with_lint_attrs(field.hir_id, |field_builder| {
+                            field_builder.visit_id(field.hir_id);
+                            field_builder.visit_ident(field.ident);
+                            field_builder.visit_expr(field.expr);
+                        });
+                    }
+                    if let Some(base_expr) = base_expr {
+                        builder.visit_expr(base_expr);
+                    }
+                });
+            }
+            _ => self.with_lint_attrs(e.hir_id, |builder| {
+                intravisit::walk_expr(builder, e);
+            }),
+        }
     }
 
     fn visit_field_def(&mut self, s: &'tcx hir::FieldDef<'tcx>) {
@@ -801,6 +818,28 @@ impl<'tcx> intravisit::Visitor<'tcx> for LintLevelMapBuilder<'tcx> {
             intravisit::walk_impl_item(builder, impl_item);
         });
     }
+
+    fn visit_pat(&mut self, p: &'tcx hir::Pat<'tcx>) {
+        match &p.kind {
+            hir::PatKind::Struct(qpath, fields, _) => {
+                self.visit_qpath(&qpath, p.hir_id, p.span);
+                for field in *fields {
+                    self.with_lint_attrs(field.hir_id, |builder| {
+                        builder.visit_id(field.hir_id);
+                        builder.visit_ident(field.ident);
+                        builder.visit_pat(field.pat);
+                    })
+                }
+            }
+            _ => intravisit::walk_pat(self, p),
+        }
+    }
+
+    fn visit_generic_param(&mut self, p: &'tcx hir::GenericParam<'tcx>) {
+        self.with_lint_attrs(p.hir_id, |builder| {
+            intravisit::walk_generic_param(builder, p);
+        });
+    }
 }
 
 pub fn provide(providers: &mut Providers) {

src/test/ui/lint/lint-attr-everywhere-early.rs

@@ -0,0 +1,169 @@
+// Tests that lint levels can be set for early lints.
+#![allow(non_camel_case_types, unsafe_code, while_true, unused_parens)]
+
+// The following is a check of the lints used here to verify they do not warn
+// when allowed.
+fn verify_no_warnings() {
+    type non_camel_type = i32; // non_camel_case_types
+    struct NON_CAMEL_IS_ALLOWED; // non_camel_case_types
+    unsafe {} // unsafe_code
+    enum Enum {
+        VARIANT_CAMEL // non_camel_case_types
+    }
+    fn generics<foo>() {} // non_camel_case_types
+    while true {} // while_true
+    type T = (i32); // unused_parens
+}
+
+
+// ################## Types
+
+#[deny(non_camel_case_types)]
+type type_outer = i32; //~ ERROR type `type_outer` should have an upper camel case name
+
+type BareFnPtr = fn(#[deny(unused_parens)](i32)); //~ ERROR unnecessary parentheses around type
+// There aren't any early lints that currently apply to the variadic spot.
+// type BareFnPtrVariadic = extern "C" fn(i32, #[deny()]...);
+
+// ################## Items
+#[deny(non_camel_case_types)]
+struct ITEM_OUTER; //~ ERROR type `ITEM_OUTER` should have an upper camel case name
+
+mod module_inner {
+    #![deny(unsafe_code)]
+    fn f() {
+        unsafe {} //~ ERROR usage of an `unsafe` block
+    }
+}
+
+struct Associated;
+impl Associated {
+    #![deny(unsafe_code)]
+
+    fn inherent_denied_from_inner() { unsafe {} } //~ usage of an `unsafe` block
+
+    #[deny(while_true)]
+    fn inherent_fn() { while true {} } //~ ERROR denote infinite loops with
+
+    #[deny(while_true)]
+    const INHERENT_CONST: i32 = {while true {} 1}; //~ ERROR denote infinite loops with
+}
+
+trait trait_inner { //~ ERROR trait `trait_inner` should have an upper camel case name
+    #![deny(non_camel_case_types)]
+}
+
+trait AssociatedTrait {
+    #![deny(unsafe_code)]
+
+    fn denied_from_inner() { unsafe {} } //~ ERROR usage of an `unsafe` block
+
+    #[deny(while_true)]
+    fn assoc_fn() { while true {} } //~ ERROR denote infinite loops with
+
+    #[deny(while_true)]
+    const ASSOC_CONST: i32 = {while true {} 1}; //~ ERROR denote infinite loops with
+
+    #[deny(non_camel_case_types)]
+    type assoc_type; //~ ERROR associated type `assoc_type` should have an upper camel case name
+}
+
+impl AssociatedTrait for Associated {
+    #![deny(unsafe_code)]
+
+    fn denied_from_inner() { unsafe {} } //~ ERROR usage of an `unsafe` block
+
+    #[deny(while_true)]
+    fn assoc_fn() { while true {} } //~ ERROR denote infinite loops with
+
+    #[deny(while_true)]
+    const ASSOC_CONST: i32 = {while true {} 1};  //~ ERROR denote infinite loops with
+
+    #[deny(unused_parens)]
+    type assoc_type = (i32); //~ ERROR unnecessary parentheses around type
+}
+
+struct StructFields {
+    #[deny(unused_parens)]f1: (i32), //~ ERROR unnecessary parentheses around type
+}
+struct StructTuple(#[deny(unused_parens)](i32)); //~ ERROR unnecessary parentheses around type
+
+enum Enum {
+    #[deny(non_camel_case_types)]
+    VARIANT_CAMEL, //~ ERROR variant `VARIANT_CAMEL` should have an upper camel case name
+}
+
+extern "C" {
+    #![deny(unused_parens)]
+
+    fn foreign_denied_from_inner(x: (i32)); //~ ERROR unnecessary parentheses around type
+}
+
+extern "C" {
+    #[deny(unused_parens)]
+    fn foreign_denied_from_outer(x: (i32)); //~ ERROR unnecessary parentheses around type
+}
+
+fn function(#[deny(unused_parens)] param: (i32)) {} //~ ERROR unnecessary parentheses around type
+
+fn generics<#[deny(non_camel_case_types)]foo>() {} //~ ERROR type parameter `foo` should have an upper camel case name
+
+
+// ################## Statements
+fn statements() {
+    #[deny(unused_parens)]
+    let x = (1); //~ ERROR unnecessary parentheses around assigned value
+}
+
+
+// ################## Expressions
+fn expressions() {
+    let closure = |#[deny(unused_parens)] param: (i32)| {}; //~ ERROR unnecessary parentheses around type
+
+    struct Match{f1: i32}
+    // Strangely unused_parens doesn't fire with {f1: (123)}
+    let f = Match{#[deny(unused_parens)]f1: {(123)}}; //~ ERROR unnecessary parentheses around block return value
+
+    match f {
+        #![deny(unsafe_code)]
+
+        #[deny(while_true)]
+        Match{f1} => {
+            unsafe {} //~ ERROR usage of an `unsafe` block
+            while true {} //~ ERROR denote infinite loops with
+        }
+    }
+
+    // Statement Block
+    {
+        #![deny(unsafe_code)]
+        unsafe {} //~ ERROR usage of an `unsafe` block
+    }
+    let block_tail = {
+        #[deny(unsafe_code)]
+        unsafe {} //~ ERROR usage of an `unsafe` block
+    };
+
+    // Before expression as a statement.
+    #[deny(unsafe_code)]
+    unsafe {}; //~ ERROR usage of an `unsafe` block
+
+    [#[deny(unsafe_code)] unsafe {123}]; //~ ERROR usage of an `unsafe` block
+    (#[deny(unsafe_code)] unsafe {123},); //~ ERROR usage of an `unsafe` block
+    fn call(p: i32) {}
+    call(#[deny(unsafe_code)] unsafe {123}); //~ ERROR usage of an `unsafe` block
+    struct TupleStruct(i32);
+    TupleStruct(#[deny(unsafe_code)] unsafe {123}); //~ ERROR usage of an `unsafe` block
+}
+
+
+// ################## Patterns
+fn patterns() {
+    // There aren't any early lints that I can find that apply to pattern fields.
+    //
+    // struct PatField{f1: i32, f2: i32};
+    // let f = PatField{f1: 1, f2: 2};
+    // let PatField{#[deny()]f1, #[deny()]..} = f;
+}
+
+fn main() {}