Merge pull request #122 from Manishearth/strings
New string_add_assign lint
This commit is contained in:
llogiq
commit
48a9ed9b33
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@ -29,6 +29,7 @@ Lints included in this crate:
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- `inline_always`: Warns on `#[inline(always)]`, because in most cases it is a bad idea
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- `collapsible_if`: Warns on cases where two nested `if`-expressions can be collapsed into one, e.g. `if x { if y { foo() } }` can be written as `if x && y { foo() }`
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- `zero_width_space`: Warns on encountering a unicode zero-width space
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- `string_add_assign`: Warns on `x = x + ..` where `x` is a `String` and suggests using `push_str(..)` instead.
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To use, add the following lines to your Cargo.toml:
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277
src/eq_op.rs
277
src/eq_op.rs
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@ -23,238 +23,237 @@ impl LintPass for EqOp {
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if let ExprBinary(ref op, ref left, ref right) = e.node {
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if is_cmp_or_bit(op) && is_exp_equal(left, right) {
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span_lint(cx, EQ_OP, e.span, &format!(
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"equal expressions as operands to {}",
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ast_util::binop_to_string(op.node)));
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"equal expressions as operands to {}",
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ast_util::binop_to_string(op.node)));
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}
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}
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}
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}
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fn is_exp_equal(left : &Expr, right : &Expr) -> bool {
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match (&left.node, &right.node) {
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(&ExprBinary(ref lop, ref ll, ref lr),
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&ExprBinary(ref rop, ref rl, ref rr)) =>
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lop.node == rop.node &&
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is_exp_equal(ll, rl) && is_exp_equal(lr, rr),
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(&ExprBox(ref lpl, ref lbox), &ExprBox(ref rpl, ref rbox)) =>
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both(lpl, rpl, |l, r| is_exp_equal(l, r)) &&
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is_exp_equal(lbox, rbox),
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(&ExprCall(ref lcallee, ref largs),
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&ExprCall(ref rcallee, ref rargs)) => is_exp_equal(lcallee,
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rcallee) && is_exps_equal(largs, rargs),
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(&ExprCast(ref lc, ref lty), &ExprCast(ref rc, ref rty)) =>
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is_ty_equal(lty, rty) && is_exp_equal(lc, rc),
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(&ExprField(ref lfexp, ref lfident),
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&ExprField(ref rfexp, ref rfident)) =>
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lfident.node == rfident.node && is_exp_equal(lfexp, rfexp),
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(&ExprLit(ref l), &ExprLit(ref r)) => l.node == r.node,
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(&ExprMethodCall(ref lident, ref lcty, ref lmargs),
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&ExprMethodCall(ref rident, ref rcty, ref rmargs)) =>
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lident.node == rident.node && is_tys_equal(lcty, rcty) &&
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is_exps_equal(lmargs, rmargs),
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(&ExprParen(ref lparen), _) => is_exp_equal(lparen, right),
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(_, &ExprParen(ref rparen)) => is_exp_equal(left, rparen),
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(&ExprPath(ref lqself, ref lsubpath),
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&ExprPath(ref rqself, ref rsubpath)) =>
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both(lqself, rqself, |l, r| is_qself_equal(l, r)) &&
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is_path_equal(lsubpath, rsubpath),
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(&ExprTup(ref ltup), &ExprTup(ref rtup)) =>
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is_exps_equal(ltup, rtup),
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(&ExprUnary(lunop, ref l), &ExprUnary(runop, ref r)) =>
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lunop == runop && is_exp_equal(l, r),
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(&ExprVec(ref l), &ExprVec(ref r)) => is_exps_equal(l, r),
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_ => false
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}
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pub fn is_exp_equal(left : &Expr, right : &Expr) -> bool {
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match (&left.node, &right.node) {
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(&ExprBinary(ref lop, ref ll, ref lr),
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&ExprBinary(ref rop, ref rl, ref rr)) =>
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lop.node == rop.node &&
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is_exp_equal(ll, rl) && is_exp_equal(lr, rr),
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(&ExprBox(ref lpl, ref lbox), &ExprBox(ref rpl, ref rbox)) =>
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both(lpl, rpl, |l, r| is_exp_equal(l, r)) &&
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is_exp_equal(lbox, rbox),
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(&ExprCall(ref lcallee, ref largs),
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&ExprCall(ref rcallee, ref rargs)) => is_exp_equal(lcallee,
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rcallee) && is_exps_equal(largs, rargs),
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(&ExprCast(ref lc, ref lty), &ExprCast(ref rc, ref rty)) =>
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is_ty_equal(lty, rty) && is_exp_equal(lc, rc),
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(&ExprField(ref lfexp, ref lfident),
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&ExprField(ref rfexp, ref rfident)) =>
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lfident.node == rfident.node && is_exp_equal(lfexp, rfexp),
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(&ExprLit(ref l), &ExprLit(ref r)) => l.node == r.node,
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(&ExprMethodCall(ref lident, ref lcty, ref lmargs),
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&ExprMethodCall(ref rident, ref rcty, ref rmargs)) =>
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lident.node == rident.node && is_tys_equal(lcty, rcty) &&
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is_exps_equal(lmargs, rmargs),
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(&ExprParen(ref lparen), _) => is_exp_equal(lparen, right),
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(_, &ExprParen(ref rparen)) => is_exp_equal(left, rparen),
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(&ExprPath(ref lqself, ref lsubpath),
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&ExprPath(ref rqself, ref rsubpath)) =>
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both(lqself, rqself, |l, r| is_qself_equal(l, r)) &&
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is_path_equal(lsubpath, rsubpath),
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(&ExprTup(ref ltup), &ExprTup(ref rtup)) =>
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is_exps_equal(ltup, rtup),
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(&ExprUnary(lunop, ref l), &ExprUnary(runop, ref r)) =>
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lunop == runop && is_exp_equal(l, r),
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(&ExprVec(ref l), &ExprVec(ref r)) => is_exps_equal(l, r),
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_ => false
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}
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}
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fn is_exps_equal(left : &[P<Expr>], right : &[P<Expr>]) -> bool {
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over(left, right, |l, r| is_exp_equal(l, r))
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over(left, right, |l, r| is_exp_equal(l, r))
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}
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fn is_path_equal(left : &Path, right : &Path) -> bool {
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// The == of idents doesn't work with different contexts,
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// we have to be explicit about hygeine
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left.global == right.global
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&& left.segments.iter().zip(right.segments.iter())
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.all( |(l,r)| l.identifier.name == r.identifier.name
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&& l.identifier.ctxt == r.identifier.ctxt
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&& l.parameters == r.parameters)
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// we have to be explicit about hygiene
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left.global == right.global && over(&left.segments, &right.segments,
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|l, r| l.identifier.name == r.identifier.name
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&& l.identifier.ctxt == r.identifier.ctxt
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&& l.parameters == r.parameters)
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}
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fn is_qself_equal(left : &QSelf, right : &QSelf) -> bool {
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left.ty.node == right.ty.node && left.position == right.position
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left.ty.node == right.ty.node && left.position == right.position
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}
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fn is_ty_equal(left : &Ty, right : &Ty) -> bool {
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match (&left.node, &right.node) {
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(&TyVec(ref lvec), &TyVec(ref rvec)) => is_ty_equal(lvec, rvec),
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(&TyFixedLengthVec(ref lfvty, ref lfvexp),
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&TyFixedLengthVec(ref rfvty, ref rfvexp)) =>
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is_ty_equal(lfvty, rfvty) && is_exp_equal(lfvexp, rfvexp),
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(&TyPtr(ref lmut), &TyPtr(ref rmut)) => is_mut_ty_equal(lmut, rmut),
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(&TyRptr(ref ltime, ref lrmut), &TyRptr(ref rtime, ref rrmut)) =>
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both(ltime, rtime, is_lifetime_equal) &&
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is_mut_ty_equal(lrmut, rrmut),
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(&TyBareFn(ref lbare), &TyBareFn(ref rbare)) =>
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is_bare_fn_ty_equal(lbare, rbare),
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match (&left.node, &right.node) {
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(&TyVec(ref lvec), &TyVec(ref rvec)) => is_ty_equal(lvec, rvec),
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(&TyFixedLengthVec(ref lfvty, ref lfvexp),
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&TyFixedLengthVec(ref rfvty, ref rfvexp)) =>
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is_ty_equal(lfvty, rfvty) && is_exp_equal(lfvexp, rfvexp),
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(&TyPtr(ref lmut), &TyPtr(ref rmut)) => is_mut_ty_equal(lmut, rmut),
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(&TyRptr(ref ltime, ref lrmut), &TyRptr(ref rtime, ref rrmut)) =>
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both(ltime, rtime, is_lifetime_equal) &&
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is_mut_ty_equal(lrmut, rrmut),
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(&TyBareFn(ref lbare), &TyBareFn(ref rbare)) =>
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is_bare_fn_ty_equal(lbare, rbare),
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(&TyTup(ref ltup), &TyTup(ref rtup)) => is_tys_equal(ltup, rtup),
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(&TyPath(ref lq, ref lpath), &TyPath(ref rq, ref rpath)) =>
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both(lq, rq, is_qself_equal) && is_path_equal(lpath, rpath),
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(&TyPath(ref lq, ref lpath), &TyPath(ref rq, ref rpath)) =>
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both(lq, rq, is_qself_equal) && is_path_equal(lpath, rpath),
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(&TyObjectSum(ref lsumty, ref lobounds),
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&TyObjectSum(ref rsumty, ref robounds)) =>
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is_ty_equal(lsumty, rsumty) &&
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is_param_bounds_equal(lobounds, robounds),
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(&TyPolyTraitRef(ref ltbounds), &TyPolyTraitRef(ref rtbounds)) =>
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is_param_bounds_equal(ltbounds, rtbounds),
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&TyObjectSum(ref rsumty, ref robounds)) =>
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is_ty_equal(lsumty, rsumty) &&
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is_param_bounds_equal(lobounds, robounds),
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(&TyPolyTraitRef(ref ltbounds), &TyPolyTraitRef(ref rtbounds)) =>
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is_param_bounds_equal(ltbounds, rtbounds),
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(&TyParen(ref lty), &TyParen(ref rty)) => is_ty_equal(lty, rty),
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(&TyTypeof(ref lof), &TyTypeof(ref rof)) => is_exp_equal(lof, rof),
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(&TyInfer, &TyInfer) => true,
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_ => false
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}
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(&TyInfer, &TyInfer) => true,
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_ => false
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}
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}
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fn is_param_bound_equal(left : &TyParamBound, right : &TyParamBound)
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-> bool {
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match(left, right) {
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(&TraitTyParamBound(ref lpoly, ref lmod),
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&TraitTyParamBound(ref rpoly, ref rmod)) =>
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lmod == rmod && is_poly_traitref_equal(lpoly, rpoly),
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-> bool {
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match(left, right) {
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(&TraitTyParamBound(ref lpoly, ref lmod),
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&TraitTyParamBound(ref rpoly, ref rmod)) =>
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lmod == rmod && is_poly_traitref_equal(lpoly, rpoly),
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(&RegionTyParamBound(ref ltime), &RegionTyParamBound(ref rtime)) =>
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is_lifetime_equal(ltime, rtime),
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is_lifetime_equal(ltime, rtime),
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_ => false
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}
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}
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}
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fn is_poly_traitref_equal(left : &PolyTraitRef, right : &PolyTraitRef)
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-> bool {
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is_lifetimedefs_equal(&left.bound_lifetimes, &right.bound_lifetimes)
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&& is_path_equal(&left.trait_ref.path, &right.trait_ref.path)
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-> bool {
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is_lifetimedefs_equal(&left.bound_lifetimes, &right.bound_lifetimes)
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&& is_path_equal(&left.trait_ref.path, &right.trait_ref.path)
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}
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fn is_param_bounds_equal(left : &TyParamBounds, right : &TyParamBounds)
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-> bool {
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over(left, right, is_param_bound_equal)
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-> bool {
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over(left, right, is_param_bound_equal)
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}
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fn is_mut_ty_equal(left : &MutTy, right : &MutTy) -> bool {
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left.mutbl == right.mutbl && is_ty_equal(&left.ty, &right.ty)
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left.mutbl == right.mutbl && is_ty_equal(&left.ty, &right.ty)
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}
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fn is_bare_fn_ty_equal(left : &BareFnTy, right : &BareFnTy) -> bool {
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left.unsafety == right.unsafety && left.abi == right.abi &&
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is_lifetimedefs_equal(&left.lifetimes, &right.lifetimes) &&
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is_fndecl_equal(&left.decl, &right.decl)
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left.unsafety == right.unsafety && left.abi == right.abi &&
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is_lifetimedefs_equal(&left.lifetimes, &right.lifetimes) &&
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is_fndecl_equal(&left.decl, &right.decl)
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}
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fn is_fndecl_equal(left : &P<FnDecl>, right : &P<FnDecl>) -> bool {
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left.variadic == right.variadic &&
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is_args_equal(&left.inputs, &right.inputs) &&
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is_fnret_ty_equal(&left.output, &right.output)
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left.variadic == right.variadic &&
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is_args_equal(&left.inputs, &right.inputs) &&
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is_fnret_ty_equal(&left.output, &right.output)
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}
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fn is_fnret_ty_equal(left : &FunctionRetTy, right : &FunctionRetTy)
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-> bool {
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match (left, right) {
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(&NoReturn(_), &NoReturn(_)) |
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(&DefaultReturn(_), &DefaultReturn(_)) => true,
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(&Return(ref lty), &Return(ref rty)) => is_ty_equal(lty, rty),
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_ => false
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}
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-> bool {
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match (left, right) {
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(&NoReturn(_), &NoReturn(_)) |
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(&DefaultReturn(_), &DefaultReturn(_)) => true,
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(&Return(ref lty), &Return(ref rty)) => is_ty_equal(lty, rty),
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_ => false
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}
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}
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fn is_arg_equal(l: &Arg, r : &Arg) -> bool {
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is_ty_equal(&l.ty, &r.ty) && is_pat_equal(&l.pat, &r.pat)
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is_ty_equal(&l.ty, &r.ty) && is_pat_equal(&l.pat, &r.pat)
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}
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fn is_args_equal(left : &[Arg], right : &[Arg]) -> bool {
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over(left, right, is_arg_equal)
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over(left, right, is_arg_equal)
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}
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fn is_pat_equal(left : &Pat, right : &Pat) -> bool {
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match(&left.node, &right.node) {
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(&PatWild(lwild), &PatWild(rwild)) => lwild == rwild,
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(&PatIdent(ref lmode, ref lident, Option::None),
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&PatIdent(ref rmode, ref rident, Option::None)) =>
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lmode == rmode && is_ident_equal(&lident.node, &rident.node),
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(&PatIdent(ref lmode, ref lident, Option::Some(ref lpat)),
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&PatIdent(ref rmode, ref rident, Option::Some(ref rpat))) =>
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lmode == rmode && is_ident_equal(&lident.node, &rident.node) &&
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is_pat_equal(lpat, rpat),
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match(&left.node, &right.node) {
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(&PatWild(lwild), &PatWild(rwild)) => lwild == rwild,
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(&PatIdent(ref lmode, ref lident, Option::None),
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&PatIdent(ref rmode, ref rident, Option::None)) =>
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lmode == rmode && is_ident_equal(&lident.node, &rident.node),
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(&PatIdent(ref lmode, ref lident, Option::Some(ref lpat)),
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&PatIdent(ref rmode, ref rident, Option::Some(ref rpat))) =>
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lmode == rmode && is_ident_equal(&lident.node, &rident.node) &&
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is_pat_equal(lpat, rpat),
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(&PatEnum(ref lpath, ref lenum), &PatEnum(ref rpath, ref renum)) =>
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is_path_equal(lpath, rpath) && both(lenum, renum, |l, r|
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is_pats_equal(l, r)),
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is_path_equal(lpath, rpath) && both(lenum, renum, |l, r|
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is_pats_equal(l, r)),
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(&PatStruct(ref lpath, ref lfieldpat, lbool),
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&PatStruct(ref rpath, ref rfieldpat, rbool)) =>
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lbool == rbool && is_path_equal(lpath, rpath) &&
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is_spanned_fieldpats_equal(lfieldpat, rfieldpat),
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&PatStruct(ref rpath, ref rfieldpat, rbool)) =>
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lbool == rbool && is_path_equal(lpath, rpath) &&
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is_spanned_fieldpats_equal(lfieldpat, rfieldpat),
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(&PatTup(ref ltup), &PatTup(ref rtup)) => is_pats_equal(ltup, rtup),
|
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(&PatBox(ref lboxed), &PatBox(ref rboxed)) =>
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is_pat_equal(lboxed, rboxed),
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is_pat_equal(lboxed, rboxed),
|
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(&PatRegion(ref lpat, ref lmut), &PatRegion(ref rpat, ref rmut)) =>
|
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is_pat_equal(lpat, rpat) && lmut == rmut,
|
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(&PatLit(ref llit), &PatLit(ref rlit)) => is_exp_equal(llit, rlit),
|
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is_pat_equal(lpat, rpat) && lmut == rmut,
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(&PatLit(ref llit), &PatLit(ref rlit)) => is_exp_equal(llit, rlit),
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(&PatRange(ref lfrom, ref lto), &PatRange(ref rfrom, ref rto)) =>
|
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is_exp_equal(lfrom, rfrom) && is_exp_equal(lto, rto),
|
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is_exp_equal(lfrom, rfrom) && is_exp_equal(lto, rto),
|
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(&PatVec(ref lfirst, Option::None, ref llast),
|
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&PatVec(ref rfirst, Option::None, ref rlast)) =>
|
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is_pats_equal(lfirst, rfirst) && is_pats_equal(llast, rlast),
|
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&PatVec(ref rfirst, Option::None, ref rlast)) =>
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||||
is_pats_equal(lfirst, rfirst) && is_pats_equal(llast, rlast),
|
||||
(&PatVec(ref lfirst, Option::Some(ref lpat), ref llast),
|
||||
&PatVec(ref rfirst, Option::Some(ref rpat), ref rlast)) =>
|
||||
is_pats_equal(lfirst, rfirst) && is_pat_equal(lpat, rpat) &&
|
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is_pats_equal(llast, rlast),
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||||
// I don't match macros for now, the code is slow enough as is ;-)
|
||||
_ => false
|
||||
}
|
||||
&PatVec(ref rfirst, Option::Some(ref rpat), ref rlast)) =>
|
||||
is_pats_equal(lfirst, rfirst) && is_pat_equal(lpat, rpat) &&
|
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is_pats_equal(llast, rlast),
|
||||
// I don't match macros for now, the code is slow enough as is ;-)
|
||||
_ => false
|
||||
}
|
||||
}
|
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|
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fn is_spanned_fieldpats_equal(left : &[code::Spanned<FieldPat>],
|
||||
right : &[code::Spanned<FieldPat>]) -> bool {
|
||||
over(left, right, |l, r| is_fieldpat_equal(&l.node, &r.node))
|
||||
right : &[code::Spanned<FieldPat>]) -> bool {
|
||||
over(left, right, |l, r| is_fieldpat_equal(&l.node, &r.node))
|
||||
}
|
||||
|
||||
fn is_fieldpat_equal(left : &FieldPat, right : &FieldPat) -> bool {
|
||||
left.is_shorthand == right.is_shorthand &&
|
||||
is_ident_equal(&left.ident, &right.ident) &&
|
||||
is_pat_equal(&left.pat, &right.pat)
|
||||
left.is_shorthand == right.is_shorthand &&
|
||||
is_ident_equal(&left.ident, &right.ident) &&
|
||||
is_pat_equal(&left.pat, &right.pat)
|
||||
}
|
||||
|
||||
fn is_ident_equal(left : &Ident, right : &Ident) -> bool {
|
||||
&left.name == &right.name && left.ctxt == right.ctxt
|
||||
&left.name == &right.name && left.ctxt == right.ctxt
|
||||
}
|
||||
|
||||
fn is_pats_equal(left : &[P<Pat>], right : &[P<Pat>]) -> bool {
|
||||
over(left, right, |l, r| is_pat_equal(l, r))
|
||||
over(left, right, |l, r| is_pat_equal(l, r))
|
||||
}
|
||||
|
||||
fn is_lifetimedef_equal(left : &LifetimeDef, right : &LifetimeDef)
|
||||
-> bool {
|
||||
is_lifetime_equal(&left.lifetime, &right.lifetime) &&
|
||||
over(&left.bounds, &right.bounds, is_lifetime_equal)
|
||||
-> bool {
|
||||
is_lifetime_equal(&left.lifetime, &right.lifetime) &&
|
||||
over(&left.bounds, &right.bounds, is_lifetime_equal)
|
||||
}
|
||||
|
||||
fn is_lifetimedefs_equal(left : &[LifetimeDef], right : &[LifetimeDef])
|
||||
-> bool {
|
||||
over(left, right, is_lifetimedef_equal)
|
||||
-> bool {
|
||||
over(left, right, is_lifetimedef_equal)
|
||||
}
|
||||
|
||||
fn is_lifetime_equal(left : &Lifetime, right : &Lifetime) -> bool {
|
||||
left.name == right.name
|
||||
left.name == right.name
|
||||
}
|
||||
|
||||
fn is_tys_equal(left : &[P<Ty>], right : &[P<Ty>]) -> bool {
|
||||
over(left, right, |l, r| is_ty_equal(l, r))
|
||||
over(left, right, |l, r| is_ty_equal(l, r))
|
||||
}
|
||||
|
||||
fn over<X, F>(left: &[X], right: &[X], mut eq_fn: F) -> bool
|
||||
where F: FnMut(&X, &X) -> bool {
|
||||
where F: FnMut(&X, &X) -> bool {
|
||||
left.len() == right.len() && left.iter().zip(right).all(|(x, y)|
|
||||
eq_fn(x, y))
|
||||
eq_fn(x, y))
|
||||
}
|
||||
|
||||
fn both<X, F>(l: &Option<X>, r: &Option<X>, mut eq_fn : F) -> bool
|
||||
where F: FnMut(&X, &X) -> bool {
|
||||
l.as_ref().map_or_else(|| r.is_none(), |x| r.as_ref().map_or(false,
|
||||
|y| eq_fn(x, y)))
|
||||
where F: FnMut(&X, &X) -> bool {
|
||||
l.as_ref().map_or_else(|| r.is_none(), |x| r.as_ref().map_or(false,
|
||||
|y| eq_fn(x, y)))
|
||||
}
|
||||
|
||||
fn is_cmp_or_bit(op : &BinOp) -> bool {
|
||||
|
|
|
|||
|
|
@ -28,6 +28,7 @@ pub mod attrs;
|
|||
pub mod collapsible_if;
|
||||
pub mod unicode;
|
||||
pub mod utils;
|
||||
pub mod strings;
|
||||
|
||||
#[plugin_registrar]
|
||||
pub fn plugin_registrar(reg: &mut Registry) {
|
||||
|
|
@ -51,6 +52,7 @@ pub fn plugin_registrar(reg: &mut Registry) {
|
|||
reg.register_lint_pass(box attrs::AttrPass as LintPassObject);
|
||||
reg.register_lint_pass(box collapsible_if::CollapsibleIf as LintPassObject);
|
||||
reg.register_lint_pass(box unicode::Unicode as LintPassObject);
|
||||
reg.register_lint_pass(box strings::StringAdd as LintPassObject);
|
||||
|
||||
reg.register_lint_group("clippy", vec![types::BOX_VEC, types::LINKEDLIST,
|
||||
misc::SINGLE_MATCH, misc::STR_TO_STRING,
|
||||
|
|
@ -70,5 +72,6 @@ pub fn plugin_registrar(reg: &mut Registry) {
|
|||
attrs::INLINE_ALWAYS,
|
||||
collapsible_if::COLLAPSIBLE_IF,
|
||||
unicode::ZERO_WIDTH_SPACE,
|
||||
strings::STRING_ADD_ASSIGN,
|
||||
]);
|
||||
}
|
||||
|
|
|
|||
55
src/strings.rs
Normal file
55
src/strings.rs
Normal file
|
|
@ -0,0 +1,55 @@
|
|||
//! This LintPass catches both string addition and string addition + assignment
|
||||
//!
|
||||
//! Note that since we have two lints where one subsumes the other, we try to
|
||||
//! disable the subsumed lint unless it has a higher level
|
||||
|
||||
use rustc::lint::*;
|
||||
use rustc::middle::ty::TypeVariants::TyStruct;
|
||||
use syntax::ast::*;
|
||||
use syntax::codemap::{Span, Spanned};
|
||||
use eq_op::is_exp_equal;
|
||||
use misc::walk_ty;
|
||||
use types::match_ty_unwrap;
|
||||
use utils::{match_def_path, span_lint};
|
||||
|
||||
declare_lint! {
|
||||
pub STRING_ADD_ASSIGN,
|
||||
Warn,
|
||||
"Warn on `x = x + ..` where x is a `String`"
|
||||
}
|
||||
|
||||
#[derive(Copy,Clone)]
|
||||
pub struct StringAdd;
|
||||
|
||||
impl LintPass for StringAdd {
|
||||
fn get_lints(&self) -> LintArray {
|
||||
lint_array!(STRING_ADD_ASSIGN)
|
||||
}
|
||||
|
||||
fn check_expr(&mut self, cx: &Context, e: &Expr) {
|
||||
if let &ExprAssign(ref target, ref src) = &e.node {
|
||||
if is_string(cx, target) && is_add(src, target) {
|
||||
span_lint(cx, STRING_ADD_ASSIGN, e.span,
|
||||
"You assign the result of adding something to this string. \
|
||||
Consider using `String::push_str(..) instead.")
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
fn is_string(cx: &Context, e: &Expr) -> bool {
|
||||
if let TyStruct(def_id, _) = walk_ty(cx.tcx.expr_ty(e)).sty {
|
||||
match_def_path(cx, def_id, &["std", "string", "String"])
|
||||
} else { false }
|
||||
}
|
||||
|
||||
fn is_add(src: &Expr, target: &Expr) -> bool {
|
||||
match &src.node {
|
||||
&ExprBinary(Spanned{ node: BiAdd, .. }, ref left, _) =>
|
||||
is_exp_equal(target, left),
|
||||
&ExprBlock(ref block) => block.stmts.is_empty() &&
|
||||
block.expr.as_ref().map_or(false, |expr| is_add(&*expr, target)),
|
||||
&ExprParen(ref expr) => is_add(&*expr, target),
|
||||
_ => false
|
||||
}
|
||||
}
|
||||
|
|
@ -41,7 +41,7 @@ pub fn match_def_path(cx: &Context, def_id: DefId, path: &[&str]) -> bool {
|
|||
/// `match_path(path, &["std", "rt", "begin_unwind"])`
|
||||
pub fn match_path(path: &Path, segments: &[&str]) -> bool {
|
||||
path.segments.iter().rev().zip(segments.iter().rev()).all(
|
||||
|(a,b)| a.identifier.name == b)
|
||||
|(a,b)| &a.identifier.name.as_str() == b)
|
||||
}
|
||||
|
||||
/// convert a span to a code snippet if available, otherwise use default, e.g.
|
||||
|
|
|
|||
12
tests/compile-fail/strings.rs
Normal file
12
tests/compile-fail/strings.rs
Normal file
|
|
@ -0,0 +1,12 @@
|
|||
#![feature(plugin)]
|
||||
#![plugin(clippy)]
|
||||
|
||||
#![deny(string_add_assign)]
|
||||
|
||||
fn main() {
|
||||
let x = "".to_owned();
|
||||
|
||||
for i in (1..3) {
|
||||
x = x + "."; //~ERROR
|
||||
}
|
||||
}
|
||||
Loading…
Reference in a new issue