use rustc::cfg::CFG;
use rustc::lint::*;
-use rustc::ty;
+use rustc::{declare_lint, lint_array};
use rustc::hir::*;
-use rustc::hir::intravisit::{Visitor, walk_expr, NestedVisitorMap};
-use syntax::ast::Attribute;
-use syntax::attr;
+use rustc::ty;
+use rustc::hir::intravisit::{walk_expr, NestedVisitorMap, Visitor};
+use syntax::ast::{Attribute, NodeId};
use syntax::codemap::Span;
-use utils::{in_macro, LimitStack, span_help_and_lint, paths, match_type};
+use crate::utils::{in_macro, is_allowed, match_type, paths, span_help_and_lint, LimitStack};
/// **What it does:** Checks for methods with high cyclomatic complexity.
///
/// **Why is this bad?** Methods of high cyclomatic complexity tend to be badly
/// readable. Also LLVM will usually optimize small methods better.
///
-/// **Known problems:** Sometimes it's hard to find a way to reduce the complexity.
+/// **Known problems:** Sometimes it's hard to find a way to reduce the
+/// complexity.
///
/// **Example:** No. You'll see it when you get the warning.
-declare_lint! {
+declare_clippy_lint! {
pub CYCLOMATIC_COMPLEXITY,
- Warn,
+ complexity,
"functions that should be split up into multiple functions"
}
impl CyclomaticComplexity {
pub fn new(limit: u64) -> Self {
- CyclomaticComplexity { limit: LimitStack::new(limit) }
+ Self {
+ limit: LimitStack::new(limit),
+ }
}
}
}
impl CyclomaticComplexity {
- fn check<'a, 'tcx: 'a>(&mut self, cx: &'a LateContext<'a, 'tcx>, expr: &'tcx Expr, span: Span) {
- if in_macro(cx, span) {
+ fn check<'a, 'tcx: 'a>(&mut self, cx: &'a LateContext<'a, 'tcx>, body: &'tcx Body, span: Span) {
+ if in_macro(span) {
return;
}
- let cfg = CFG::new(cx.tcx, expr);
+ let cfg = CFG::new(cx.tcx, body);
+ let expr = &body.value;
let n = cfg.graph.len_nodes() as u64;
let e = cfg.graph.len_edges() as u64;
if e + 2 < n {
divergence: 0,
short_circuits: 0,
returns: 0,
- cx: cx,
+ cx,
};
helper.visit_expr(expr);
- let CCHelper { match_arms, divergence, short_circuits, returns, .. } = helper;
- let ret_ty = cx.tcx.tables().node_id_to_type(expr.id);
+ let CCHelper {
+ match_arms,
+ divergence,
+ short_circuits,
+ returns,
+ ..
+ } = helper;
+ let ret_ty = cx.tables.node_id_to_type(expr.hir_id);
let ret_adjust = if match_type(cx, ret_ty, &paths::RESULT) {
returns
} else {
};
if cc + divergence < match_arms + short_circuits {
- report_cc_bug(cx, cc, match_arms, divergence, short_circuits, ret_adjust, span);
+ report_cc_bug(
+ cx,
+ cc,
+ match_arms,
+ divergence,
+ short_circuits,
+ ret_adjust,
+ span,
+ body.id().node_id,
+ );
} else {
let mut rust_cc = cc + divergence - match_arms - short_circuits;
// prevent degenerate cases where unreachable code contains `return` statements
rust_cc -= ret_adjust;
}
if rust_cc > self.limit.limit() {
- span_help_and_lint(cx,
- CYCLOMATIC_COMPLEXITY,
- span,
- &format!("the function has a cyclomatic complexity of {}", rust_cc),
- "you could split it up into multiple smaller functions");
+ span_help_and_lint(
+ cx,
+ CYCLOMATIC_COMPLEXITY,
+ span,
+ &format!("the function has a cyclomatic complexity of {}", rust_cc),
+ "you could split it up into multiple smaller functions",
+ );
}
}
}
}
impl<'a, 'tcx> LateLintPass<'a, 'tcx> for CyclomaticComplexity {
- fn check_item(&mut self, cx: &LateContext<'a, 'tcx>, item: &'tcx Item) {
- if let ItemFn(_, _, _, _, _, eid) = item.node {
- if !attr::contains_name(&item.attrs, "test") {
- self.check(cx, cx.tcx.map.expr(eid), item.span);
- }
- }
- }
-
- fn check_impl_item(&mut self, cx: &LateContext<'a, 'tcx>, item: &'tcx ImplItem) {
- if let ImplItemKind::Method(_, eid) = item.node {
- self.check(cx, cx.tcx.map.expr(eid), item.span);
- }
- }
-
- fn check_trait_item(&mut self, cx: &LateContext<'a, 'tcx>, item: &'tcx TraitItem) {
- if let MethodTraitItem(_, Some(eid)) = item.node {
- self.check(cx, cx.tcx.map.expr(eid), item.span);
+ fn check_fn(
+ &mut self,
+ cx: &LateContext<'a, 'tcx>,
+ _: intravisit::FnKind<'tcx>,
+ _: &'tcx FnDecl,
+ body: &'tcx Body,
+ span: Span,
+ node_id: NodeId,
+ ) {
+ let def_id = cx.tcx.hir.local_def_id(node_id);
+ if !cx.tcx.has_attr(def_id, "test") {
+ self.check(cx, body, span);
}
}
fn enter_lint_attrs(&mut self, cx: &LateContext<'a, 'tcx>, attrs: &'tcx [Attribute]) {
- self.limit.push_attrs(cx.sess(), attrs, "cyclomatic_complexity");
+ self.limit
+ .push_attrs(cx.sess(), attrs, "cyclomatic_complexity");
}
fn exit_lint_attrs(&mut self, cx: &LateContext<'a, 'tcx>, attrs: &'tcx [Attribute]) {
- self.limit.pop_attrs(cx.sess(), attrs, "cyclomatic_complexity");
+ self.limit
+ .pop_attrs(cx.sess(), attrs, "cyclomatic_complexity");
}
}
impl<'a, 'tcx> Visitor<'tcx> for CCHelper<'a, 'tcx> {
fn visit_expr(&mut self, e: &'tcx Expr) {
match e.node {
- ExprMatch(_, ref arms, _) => {
+ ExprKind::Match(_, ref arms, _) => {
walk_expr(self, e);
let arms_n: u64 = arms.iter().map(|arm| arm.pats.len() as u64).sum();
if arms_n > 1 {
self.match_arms += arms_n - 2;
}
- }
- ExprCall(ref callee, _) => {
+ },
+ ExprKind::Call(ref callee, _) => {
walk_expr(self, e);
- let ty = self.cx.tcx.tables().node_id_to_type(callee.id);
+ let ty = self.cx.tables.node_id_to_type(callee.hir_id);
match ty.sty {
- ty::TyFnDef(_, _, ty) |
- ty::TyFnPtr(ty) if ty.sig.skip_binder().output.sty == ty::TyNever => {
- self.divergence += 1;
- }
+ ty::TyFnDef(..) | ty::TyFnPtr(_) => {
+ let sig = ty.fn_sig(self.cx.tcx);
+ if sig.skip_binder().output().sty == ty::TyNever {
+ self.divergence += 1;
+ }
+ },
_ => (),
}
- }
- ExprClosure(..) => (),
- ExprBinary(op, _, _) => {
+ },
+ ExprKind::Closure(.., _) => (),
+ ExprKind::Binary(op, _, _) => {
walk_expr(self, e);
match op.node {
- BiAnd | BiOr => self.short_circuits += 1,
+ BinOpKind::And | BinOpKind::Or => self.short_circuits += 1,
_ => (),
}
- }
- ExprRet(_) => self.returns += 1,
+ },
+ ExprKind::Ret(_) => self.returns += 1,
_ => walk_expr(self, e),
}
}
}
}
-#[cfg(feature="debugging")]
-fn report_cc_bug(_: &LateContext, cc: u64, narms: u64, div: u64, shorts: u64, returns: u64, span: Span) {
- span_bug!(span,
- "Clippy encountered a bug calculating cyclomatic complexity: cc = {}, arms = {}, \
- div = {}, shorts = {}, returns = {}. Please file a bug report.",
- cc,
- narms,
- div,
- shorts,
- returns);
+#[cfg(feature = "debugging")]
+#[allow(too_many_arguments)]
+fn report_cc_bug(_: &LateContext, cc: u64, narms: u64, div: u64, shorts: u64, returns: u64, span: Span, _: NodeId) {
+ span_bug!(
+ span,
+ "Clippy encountered a bug calculating cyclomatic complexity: cc = {}, arms = {}, \
+ div = {}, shorts = {}, returns = {}. Please file a bug report.",
+ cc,
+ narms,
+ div,
+ shorts,
+ returns
+ );
}
-#[cfg(not(feature="debugging"))]
-fn report_cc_bug(cx: &LateContext, cc: u64, narms: u64, div: u64, shorts: u64, returns: u64, span: Span) {
- if cx.current_level(CYCLOMATIC_COMPLEXITY) != Level::Allow {
- cx.sess().span_note_without_error(span,
- &format!("Clippy encountered a bug calculating cyclomatic complexity \
- (hide this message with `#[allow(cyclomatic_complexity)]`): \
- cc = {}, arms = {}, div = {}, shorts = {}, returns = {}. \
- Please file a bug report.",
- cc,
- narms,
- div,
- shorts,
- returns));
+#[cfg(not(feature = "debugging"))]
+#[allow(too_many_arguments)]
+fn report_cc_bug(cx: &LateContext, cc: u64, narms: u64, div: u64, shorts: u64, returns: u64, span: Span, id: NodeId) {
+ if !is_allowed(cx, CYCLOMATIC_COMPLEXITY, id) {
+ cx.sess().span_note_without_error(
+ span,
+ &format!(
+ "Clippy encountered a bug calculating cyclomatic complexity \
+ (hide this message with `#[allow(cyclomatic_complexity)]`): \
+ cc = {}, arms = {}, div = {}, shorts = {}, returns = {}. \
+ Please file a bug report.",
+ cc,
+ narms,
+ div,
+ shorts,
+ returns
+ ),
+ );
}
}
projects / rust.git / blobdiff