Reduce cyclomatic complexity of types::check_ty

This commit is contained in:
Manish Goregaokar 2017-09-25 19:44:50 -07:00
parent fabb6b6645
commit 2551bd8924
No known key found for this signature in database
GPG Key ID: 3BBF4D3E2EF79F98
2 changed files with 55 additions and 48 deletions

View File

@ -184,16 +184,16 @@ fn check_ty(cx: &LateContext, ast_ty: &hir::Ty, is_local: bool) {
check_ty(cx, ty, is_local);
for ty in p.segments
.iter()
.filter_map(|ref seg| seg.parameters.as_ref())
.flat_map(|ref params| params.types.iter())
.filter_map(|seg| seg.parameters.as_ref())
.flat_map(|params| params.types.iter())
{
check_ty(cx, ty, is_local);
}
},
QPath::Resolved(None, ref p) => for ty in p.segments
.iter()
.filter_map(|ref seg| seg.parameters.as_ref())
.flat_map(|ref params| params.types.iter())
.filter_map(|seg| seg.parameters.as_ref())
.flat_map(|params| params.types.iter())
{
check_ty(cx, ty, is_local);
},
@ -207,49 +207,7 @@ fn check_ty(cx: &LateContext, ast_ty: &hir::Ty, is_local: bool) {
},
}
},
TyRptr(ref lt, MutTy { ref ty, ref mutbl }) => {
match ty.node {
TyPath(ref qpath) => {
let hir_id = cx.tcx.hir.node_to_hir_id(ty.id);
let def = cx.tables.qpath_def(qpath, hir_id);
if_let_chain! {[
let Some(def_id) = opt_def_id(def),
Some(def_id) == cx.tcx.lang_items().owned_box(),
let QPath::Resolved(None, ref path) = *qpath,
let [ref bx] = *path.segments,
let Some(ref params) = bx.parameters,
!params.parenthesized,
let [ref inner] = *params.types
], {
if is_any_trait(inner) {
// Ignore `Box<Any>` types, see #1884 for details.
return;
}
let ltopt = if lt.is_elided() {
"".to_owned()
} else {
format!("{} ", lt.name.name().as_str())
};
let mutopt = if *mutbl == Mutability::MutMutable {
"mut "
} else {
""
};
span_lint_and_sugg(cx,
BORROWED_BOX,
ast_ty.span,
"you seem to be trying to use `&Box<T>`. Consider using just `&T`",
"try",
format!("&{}{}{}", ltopt, mutopt, &snippet(cx, inner.span, ".."))
);
return; // don't recurse into the type
}};
check_ty(cx, ty, is_local);
},
_ => check_ty(cx, ty, is_local),
}
},
TyRptr(ref lt, ref mut_ty) => check_ty_rptr(cx, ast_ty, is_local, lt, mut_ty),
// recurse
TySlice(ref ty) | TyArray(ref ty, _) | TyPtr(MutTy { ref ty, .. }) => check_ty(cx, ty, is_local),
TyTup(ref tys) => for ty in tys {
@ -259,6 +217,50 @@ fn check_ty(cx: &LateContext, ast_ty: &hir::Ty, is_local: bool) {
}
}
fn check_ty_rptr(cx: &LateContext, ast_ty: &hir::Ty, is_local: bool, lt: &Lifetime, mut_ty: &MutTy) {
match mut_ty.ty.node {
TyPath(ref qpath) => {
let hir_id = cx.tcx.hir.node_to_hir_id(mut_ty.ty.id);
let def = cx.tables.qpath_def(qpath, hir_id);
if_let_chain! {[
let Some(def_id) = opt_def_id(def),
Some(def_id) == cx.tcx.lang_items().owned_box(),
let QPath::Resolved(None, ref path) = *qpath,
let [ref bx] = *path.segments,
let Some(ref params) = bx.parameters,
!params.parenthesized,
let [ref inner] = *params.types
], {
if is_any_trait(inner) {
// Ignore `Box<Any>` types, see #1884 for details.
return;
}
let ltopt = if lt.is_elided() {
"".to_owned()
} else {
format!("{} ", lt.name.name().as_str())
};
let mutopt = if mut_ty.mutbl == Mutability::MutMutable {
"mut "
} else {
""
};
span_lint_and_sugg(cx,
BORROWED_BOX,
ast_ty.span,
"you seem to be trying to use `&Box<T>`. Consider using just `&T`",
"try",
format!("&{}{}{}", ltopt, mutopt, &snippet(cx, inner.span, ".."))
);
return; // don't recurse into the type
}};
check_ty(cx, &mut_ty.ty, is_local);
},
_ => check_ty(cx, &mut_ty.ty, is_local),
}
}
// Returns true if given type is `Any` trait.
fn is_any_trait(t: &hir::Ty) -> bool {
if_let_chain! {[

View File

@ -59,7 +59,12 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for UseSelf {
let Ty_::TyPath(QPath::Resolved(_, ref item_path)) = item_type.node,
], {
let parameters = &item_path.segments.last().expect(SEGMENTS_MSG).parameters;
if parameters.is_none() {
let should_check = if let Some(ref params) = *parameters {
!params.parenthesized && params.lifetimes.len() == 0
} else {
true
};
if should_check {
let visitor = &mut UseSelfVisitor {
item_path: item_path,
cx: cx,