enum glob use and copies left

Author: oli-obk

clippy_lints/src/enum_glob_use.rs

@@ -48,6 +48,8 @@ impl EnumGlobUse {
             return; // re-exports are fine
         }
         if let ItemUse(ref path, UseKind::Glob) = item.node {
+            // FIXME: ask jseyfried why the qpath.def for `use std::cmp::Ordering::*;`
+            // extracted through `ItemUse(ref qpath, UseKind::Glob)` is a `Mod` and not an `Enum`
             if let Def::Enum(_) = path.def {
                 span_lint(cx, ENUM_GLOB_USE, item.span, "don't use glob imports for enum variants");
             }

clippy_lints/src/lifetimes.rs

@@ -5,7 +5,7 @@ use rustc::hir::*;
 use rustc::hir::intravisit::{Visitor, walk_ty, walk_ty_param_bound, walk_fn_decl, walk_generics};
 use std::collections::{HashSet, HashMap};
 use syntax::codemap::Span;
-use utils::{in_external_macro, span_lint};
+use utils::{in_external_macro, span_lint, last_path_segment};
 
 /// **What it does:** Checks for lifetime annotations which can be removed by
 /// relying on lifetime elision.
@@ -240,26 +240,24 @@ impl<'v, 't> RefVisitor<'v, 't> {
     }
 
     fn collect_anonymous_lifetimes(&mut self, qpath: &QPath, ty: &Ty) {
-        if let QPath::Resolved(_, ref path) = *qpath {
-            let last_path_segment = path.segments.last().map(|s| &s.parameters);
-            if let Some(&AngleBracketedParameters(ref params)) = last_path_segment {
-                if params.lifetimes.is_empty() {
-                    match self.cx.tcx.tables().qpath_def(qpath, ty.id) {
-                        Def::TyAlias(def_id) |
-                        Def::Struct(def_id) => {
-                            let generics = self.cx.tcx.item_generics(def_id);
-                            for _ in generics.regions.as_slice() {
-                                self.record(&None);
-                            }
+        let last_path_segment = &last_path_segment(qpath).parameters;
+        if let &AngleBracketedParameters(ref params) = last_path_segment {
+            if params.lifetimes.is_empty() {
+                match self.cx.tcx.tables().qpath_def(qpath, ty.id) {
+                    Def::TyAlias(def_id) |
+                    Def::Struct(def_id) => {
+                        let generics = self.cx.tcx.item_generics(def_id);
+                        for _ in generics.regions.as_slice() {
+                            self.record(&None);
                         }
-                        Def::Trait(def_id) => {
-                            let trait_def = self.cx.tcx.trait_defs.borrow()[&def_id];
-                            for _ in &trait_def.generics.regions {
-                                self.record(&None);
-                            }
+                    }
+                    Def::Trait(def_id) => {
+                        let trait_def = self.cx.tcx.trait_defs.borrow()[&def_id];
+                        for _ in &trait_def.generics.regions {
+                            self.record(&None);
                         }
-                        _ => (),
                     }
+                    _ => (),
                 }
             }
         }

clippy_lints/src/loops.rs

@@ -16,7 +16,7 @@ use utils::sugg;
 
 use utils::{snippet, span_lint, get_parent_expr, match_trait_method, match_type, multispan_sugg,
             in_external_macro, is_refutable, span_help_and_lint, is_integer_literal,
-            get_enclosing_block, span_lint_and_then, higher, walk_ptrs_ty};
+            get_enclosing_block, span_lint_and_then, higher, walk_ptrs_ty, last_path_segment};
 use utils::paths;
 
 /// **What it does:** Checks for looping over the range of `0..len` of some
@@ -369,26 +369,23 @@ impl LateLintPass for Pass {
             if let (&PatKind::TupleStruct(ref qpath, ref pat_args, _),
                     &ExprMethodCall(method_name, _, ref method_args)) = (pat, &match_expr.node) {
                 let iter_expr = &method_args[0];
-                if let QPath::Resolved(_, ref path) = *qpath {
-                    if let Some(lhs_constructor) = path.segments.last() {
-                        if &*method_name.node.as_str() == "next" &&
-                           match_trait_method(cx, match_expr, &paths::ITERATOR) &&
-                           &*lhs_constructor.name.as_str() == "Some" &&
-                           !is_refutable(cx, &pat_args[0]) &&
-                           !is_iterator_used_after_while_let(cx, iter_expr) {
-                            let iterator = snippet(cx, method_args[0].span, "_");
-                            let loop_var = snippet(cx, pat_args[0].span, "_");
-                            span_lint_and_then(cx,
-                                               WHILE_LET_ON_ITERATOR,
-                                               expr.span,
-                                               "this loop could be written as a `for` loop",
-                                               |db| {
-                            db.span_suggestion(expr.span,
-                                               "try",
-                                               format!("for {} in {} {{ .. }}", loop_var, iterator));
-                            });
-                        }
-                    }
+                let lhs_constructor = last_path_segment(qpath);
+                if &*method_name.node.as_str() == "next" &&
+                   match_trait_method(cx, match_expr, &paths::ITERATOR) &&
+                   &*lhs_constructor.name.as_str() == "Some" &&
+                   !is_refutable(cx, &pat_args[0]) &&
+                   !is_iterator_used_after_while_let(cx, iter_expr) {
+                    let iterator = snippet(cx, method_args[0].span, "_");
+                    let loop_var = snippet(cx, pat_args[0].span, "_");
+                    span_lint_and_then(cx,
+                                       WHILE_LET_ON_ITERATOR,
+                                       expr.span,
+                                       "this loop could be written as a `for` loop",
+                                       |db| {
+                    db.span_suggestion(expr.span,
+                                       "try",
+                                       format!("for {} in {} {{ .. }}", loop_var, iterator));
+                    });
                 }
             }
         }

clippy_lints/src/methods.rs

@@ -3,14 +3,16 @@ use rustc::lint::*;
 use rustc::middle::const_val::ConstVal;
 use rustc::middle::const_qualif::ConstQualif;
 use rustc::ty;
+use rustc::hir::def::Def;
 use rustc_const_eval::EvalHint::ExprTypeChecked;
 use rustc_const_eval::eval_const_expr_partial;
 use std::borrow::Cow;
 use std::fmt;
 use syntax::codemap::Span;
 use utils::{get_trait_def_id, implements_trait, in_external_macro, in_macro, is_copy, match_path,
             match_trait_method, match_type, method_chain_args, return_ty, same_tys, snippet,
-            span_lint, span_lint_and_then, span_note_and_lint, walk_ptrs_ty, walk_ptrs_ty_depth};
+            span_lint, span_lint_and_then, span_note_and_lint, walk_ptrs_ty, walk_ptrs_ty_depth,
+            last_path_segment, single_segment_path, match_def_path};
 use utils::paths;
 use utils::sugg;
 
@@ -701,12 +703,8 @@ fn lint_or_fun_call(cx: &LateContext, expr: &hir::Expr, name: &str, args: &[hir:
         }
 
         if name == "unwrap_or" {
-            if let hir::ExprPath(hir::QPath::Resolved(_, ref path)) = fun.node {
-                let path: &str = &path.segments
-                                      .last()
-                                      .expect("A path must have at least one segment")
-                                      .name
-                                      .as_str();
+            if let hir::ExprPath(ref qpath) = fun.node {
+                let path: &str = &*last_path_segment(qpath).name.as_str();
 
                 if ["default", "new"].contains(&path) {
                     let arg_ty = cx.tcx.tables().expr_ty(arg);
@@ -878,7 +876,8 @@ fn lint_cstring_as_ptr(cx: &LateContext, expr: &hir::Expr, new: &hir::Expr, unwr
         let hir::ExprCall(ref fun, ref args) = new.node,
         args.len() == 1,
         let hir::ExprPath(ref path) = fun.node,
-        match_path(path, &paths::CSTRING_NEW),
+        let Def::Method(did) = cx.tcx.tables().qpath_def(path, fun.id),
+        match_def_path(cx, did, &paths::CSTRING_NEW)
     ], {
         span_lint_and_then(cx, TEMPORARY_CSTRING_AS_PTR, expr.span,
                            "you are getting the inner pointer of a temporary `CString`",
@@ -1188,8 +1187,9 @@ fn lint_chars_next(cx: &LateContext, expr: &hir::Expr, chain: &hir::Expr, other:
         let Some(args) = method_chain_args(chain, &["chars", "next"]),
         let hir::ExprCall(ref fun, ref arg_char) = other.node,
         arg_char.len() == 1,
-        let hir::ExprPath(hir::QPath::Resolved(None, ref path)) = fun.node,
-        path.segments.len() == 1 && &*path.segments[0].name.as_str() == "Some"
+        let hir::ExprPath(ref qpath) = fun.node,
+        let Some(segment) = single_segment_path(qpath),
+        &*segment.name.as_str() == "Some"
     ], {
         let self_ty = walk_ptrs_ty(cx.tcx.tables().expr_ty_adjusted(&args[0][0]));
 

clippy_lints/src/misc.rs

@@ -10,7 +10,7 @@ use rustc_const_math::ConstFloat;
 use syntax::codemap::{Span, Spanned, ExpnFormat};
 use utils::{
     get_item_name, get_parent_expr, implements_trait, in_macro, is_integer_literal, match_path,
-    snippet, span_lint, span_lint_and_then, walk_ptrs_ty
+    snippet, span_lint, span_lint_and_then, walk_ptrs_ty, last_path_segment
 };
 use utils::sugg::Sugg;
 
@@ -263,22 +263,14 @@ impl LateLintPass for Pass {
         }
         let binding = match expr.node {
             ExprPath(ref qpath) => {
-                if let QPath::Resolved(_, ref path) = *qpath {
-                    let binding = path.segments
-                        .last()
-                        .expect("path should always have at least one segment")
-                        .name
-                        .as_str();
-                    if binding.starts_with('_') &&
-                        !binding.starts_with("__") &&
-                        &*binding != "_result" && // FIXME: #944
-                        is_used(cx, expr) &&
-                        // don't lint if the declaration is in a macro
-                        non_macro_local(cx, &cx.tcx.tables().qpath_def(qpath, expr.id)) {
-                        Some(binding)
-                    } else {
-                        None
-                    }
+                let binding = last_path_segment(qpath).name.as_str();
+                if binding.starts_with('_') &&
+                    !binding.starts_with("__") &&
+                    &*binding != "_result" && // FIXME: #944
+                    is_used(cx, expr) &&
+                    // don't lint if the declaration is in a macro
+                    non_macro_local(cx, &cx.tcx.tables().qpath_def(qpath, expr.id)) {
+                    Some(binding)
                 } else {
                     None
                 }

clippy_lints/src/ranges.rs

@@ -75,17 +75,13 @@ impl LateLintPass for StepByZero {
                     // .iter() and .len() called on same Path
                     let ExprPath(QPath::Resolved(_, ref iter_path)) = iter_args[0].node,
                     let ExprPath(QPath::Resolved(_, ref len_path)) = len_args[0].node,
-                    iter_path == len_path
+                    iter_path.segments == len_path.segments
                  ], {
-                     let Path { segments: ref iter_path, .. } = **iter_path;
-                     let Path { segments: ref len_path, .. } = **len_path;
-                     if iter_path == len_path {
-                         span_lint(cx,
-                                   RANGE_ZIP_WITH_LEN,
-                                   expr.span,
-                                   &format!("It is more idiomatic to use {}.iter().enumerate()",
-                                            snippet(cx, iter_args[0].span, "_")));
-                     }
+                     span_lint(cx,
+                               RANGE_ZIP_WITH_LEN,
+                               expr.span,
+                               &format!("It is more idiomatic to use {}.iter().enumerate()",
+                                        snippet(cx, iter_args[0].span, "_")));
                 }}
             }
         }

clippy_lints/src/transmute.rs

@@ -2,7 +2,7 @@ use rustc::lint::*;
 use rustc::ty::TypeVariants::{TyRawPtr, TyRef};
 use rustc::ty;
 use rustc::hir::*;
-use utils::{match_def_path, paths, span_lint, span_lint_and_then, snippet};
+use utils::{match_def_path, paths, span_lint, span_lint_and_then, snippet, last_path_segment};
 use utils::sugg;
 
 /// **What it does:** Checks for transmutes that can't ever be correct on any
@@ -191,9 +191,8 @@ impl LateLintPass for Transmute {
 /// the type's `ToString` implementation. In weird cases it could lead to types with invalid `'_`
 /// lifetime, but it should be rare.
 fn get_type_snippet(cx: &LateContext, path: &QPath, to_rty: ty::Ty) -> String {
+    let seg = last_path_segment(path);
     if_let_chain!{[
-        let QPath::Resolved(_, ref path) = *path,
-        let Some(seg) = path.segments.last(),
         let PathParameters::AngleBracketedParameters(ref ang) = seg.parameters,
         let Some(to_ty) = ang.types.get(1),
         let TyRptr(_, ref to_ty) = to_ty.node,

clippy_lints/src/types.rs

@@ -7,7 +7,7 @@ use std::cmp::Ordering;
 use syntax::ast::{IntTy, UintTy, FloatTy};
 use syntax::codemap::Span;
 use utils::{comparisons, higher, in_external_macro, in_macro, match_def_path, snippet,
-            span_help_and_lint, span_lint, opt_def_id};
+            span_help_and_lint, span_lint, opt_def_id, last_path_segment};
 use utils::paths;
 
 /// Handles all the linting of funky types
@@ -78,9 +78,8 @@ impl LateLintPass for TypePass {
             let def = cx.tcx.tables().qpath_def(qpath, ast_ty.id);
             if let Some(def_id) = opt_def_id(def) {
                 if def_id == cx.tcx.lang_items.owned_box().unwrap() {
+                    let last = last_path_segment(qpath);
                     if_let_chain! {[
-                        let QPath::Resolved(_, ref path) = *qpath,
-                        let Some(ref last) = path.segments.last(),
                         let PathParameters::AngleBracketedParameters(ref ag) = last.parameters,
                         let Some(ref vec) = ag.types.get(0),
                         let TyPath(ref qpath) = vec.node,

clippy_lints/src/utils/higher.rs

@@ -163,7 +163,7 @@ pub fn vec_macro<'e>(cx: &LateContext, expr: &'e hir::Expr) -> Option<VecArgs<'e
             // `vec![elem; size]` case
             Some(VecArgs::Repeat(&args[0], &args[1]))
         }
-        else if match_path(path, &["into_vec"]) && args.len() == 1 {
+        else if match_def_path(cx, fun_def.def_id(), &paths::SLICE_INTO_VEC) && args.len() == 1 {
             // `vec![a, b, c]` case
             if_let_chain!{[
                 let hir::ExprBox(ref boxed) = args[0].node,

clippy_lints/src/utils/hir.rs

@@ -3,7 +3,7 @@ use rustc::lint::*;
 use rustc::hir::*;
 use std::hash::{Hash, Hasher};
 use std::collections::hash_map::DefaultHasher;
-use syntax::ast::Name;
+use syntax::ast::{Name, NodeId};
 use syntax::ptr::P;
 use utils::differing_macro_contexts;
 
@@ -457,13 +457,13 @@ impl<'a, 'tcx: 'a> SpanlessHash<'a, 'tcx> {
             ExprPath(ref qpath) => {
                 let c: fn(_) -> _ = ExprPath;
                 c.hash(&mut self.s);
-                self.hash_qpath(qpath);
+                self.hash_qpath(qpath, e.id);
             }
             ExprStruct(ref path, ref fields, ref expr) => {
                 let c: fn(_, _, _) -> _ = ExprStruct;
                 c.hash(&mut self.s);
 
-                self.hash_qpath(path);
+                self.hash_qpath(path, e.id);
 
                 for f in fields {
                     self.hash_name(&f.name.node);
@@ -528,21 +528,8 @@ impl<'a, 'tcx: 'a> SpanlessHash<'a, 'tcx> {
         n.as_str().hash(&mut self.s);
     }
 
-    pub fn hash_qpath(&mut self, p: &QPath) {
-        match *p {
-            QPath::Resolved(ref _ty, ref path) => {
-                let c: fn(_, _) -> _ = QPath::Resolved;
-                c.hash(&mut self.s);
-                // self.hash_ty(ty); FIXME
-                self.hash_path(path);
-            },
-            QPath::TypeRelative(ref _ty, ref seg) => {
-                let c: fn(_, _) -> _ = QPath::TypeRelative;
-                c.hash(&mut self.s);
-                // self.hash_ty(ty); FIXME
-                self.hash_name(&seg.name);
-            },
-        }
+    pub fn hash_qpath(&mut self, p: &QPath, id: NodeId) {
+        self.cx.tcx.tables().qpath_def(p, id).hash(&mut self.s);
     }
 
     pub fn hash_path(&mut self, p: &Path) {