diff --git a/src/copies.rs b/src/copies.rs index f8fe09c31335..38f1be92d304 100644 --- a/src/copies.rs +++ b/src/copies.rs @@ -1,6 +1,6 @@ use rustc::lint::*; use rustc_front::hir::*; -use utils::{get_parent_expr, in_macro, is_exp_equal, is_stmt_equal, over, span_lint, span_note_and_lint}; +use utils::{get_parent_expr, in_macro, is_block_equal, is_exp_equal, span_lint, span_note_and_lint}; /// **What it does:** This lint checks for consecutive `ifs` with the same condition. This lint is /// `Warn` by default. @@ -55,14 +55,7 @@ impl LateLintPass for CopyAndPaste { fn lint_same_then_else(cx: &LateContext, expr: &Expr) { if let ExprIf(_, ref then_block, Some(ref else_expr)) = expr.node { let must_lint = if let ExprBlock(ref else_block) = else_expr.node { - over(&then_block.stmts, &else_block.stmts, |l, r| is_stmt_equal(cx, l, r)) && - match (&then_block.expr, &else_block.expr) { - (&Some(ref then_expr), &Some(ref else_expr)) => { - is_exp_equal(cx, &then_expr, &else_expr) - } - (&None, &None) => true, - _ => false, - } + is_block_equal(cx, &then_block, &else_block, false) } else { false @@ -87,7 +80,7 @@ fn lint_same_cond(cx: &LateContext, expr: &Expr) { for (n, i) in conds.iter().enumerate() { for j in conds.iter().skip(n+1) { - if is_exp_equal(cx, i, j) { + if is_exp_equal(cx, i, j, true) { span_note_and_lint(cx, IFS_SAME_COND, j.span, "this if has the same condition as a previous if", i.span, "same as this"); } } diff --git a/src/entry.rs b/src/entry.rs index 64d6fa7be38b..d5bb086fc213 100644 --- a/src/entry.rs +++ b/src/entry.rs @@ -89,7 +89,7 @@ fn check_for_insert(cx: &LateContext, span: Span, map: &Expr, key: &Expr, expr: params.len() == 3, name.node.as_str() == "insert", get_item_name(cx, map) == get_item_name(cx, &*params[0]), - is_exp_equal(cx, key, ¶ms[1]) + is_exp_equal(cx, key, ¶ms[1], false) ], { let help = if sole_expr { format!("{}.entry({}).or_insert({})", diff --git a/src/eq_op.rs b/src/eq_op.rs index 49037cd9ae7f..06e4fdc6cb78 100644 --- a/src/eq_op.rs +++ b/src/eq_op.rs @@ -29,7 +29,7 @@ impl LintPass for EqOp { impl LateLintPass for EqOp { fn check_expr(&mut self, cx: &LateContext, e: &Expr) { if let ExprBinary(ref op, ref left, ref right) = e.node { - if is_cmp_or_bit(op) && is_exp_equal(cx, left, right) { + if is_cmp_or_bit(op) && is_exp_equal(cx, left, right, true) { span_lint(cx, EQ_OP, e.span, diff --git a/src/strings.rs b/src/strings.rs index f1a1341460e6..b78db7f4b771 100644 --- a/src/strings.rs +++ b/src/strings.rs @@ -84,7 +84,7 @@ impl LateLintPass for StringAdd { if let Some(ref p) = parent { if let ExprAssign(ref target, _) = p.node { // avoid duplicate matches - if is_exp_equal(cx, target, left) { + if is_exp_equal(cx, target, left, false) { return; } } @@ -113,7 +113,7 @@ fn is_string(cx: &LateContext, e: &Expr) -> bool { fn is_add(cx: &LateContext, src: &Expr, target: &Expr) -> bool { match src.node { - ExprBinary(Spanned{ node: BiAdd, .. }, ref left, _) => is_exp_equal(cx, target, left), + ExprBinary(Spanned{ node: BiAdd, .. }, ref left, _) => is_exp_equal(cx, target, left, false), ExprBlock(ref block) => { block.stmts.is_empty() && block.expr.as_ref().map_or(false, |expr| is_add(cx, expr, target)) } diff --git a/src/utils.rs b/src/utils.rs index 13fd849993f7..a8890f31cb03 100644 --- a/src/utils.rs +++ b/src/utils.rs @@ -589,59 +589,183 @@ fn parse_attrs(sess: &Session, attrs: &[ast::Attribute], name: &' } } -pub fn is_stmt_equal(cx: &LateContext, left: &Stmt, right: &Stmt) -> bool { +/// Check whether two statements are the same. +/// See also `is_exp_equal`. +pub fn is_stmt_equal(cx: &LateContext, left: &Stmt, right: &Stmt, ignore_fn: bool) -> bool { match (&left.node, &right.node) { - (&StmtExpr(ref l, _), &StmtExpr(ref r, _)) => is_exp_equal(cx, l, r), - (&StmtSemi(ref l, _), &StmtSemi(ref r, _)) => is_exp_equal(cx, l, r), + (&StmtDecl(ref l, _), &StmtDecl(ref r, _)) => { + if let (&DeclLocal(ref l), &DeclLocal(ref r)) = (&l.node, &r.node) { + // TODO: tys + l.ty.is_none() && r.ty.is_none() && + both(&l.init, &r.init, |l, r| is_exp_equal(cx, l, r, ignore_fn)) + } + else { + false + } + } + (&StmtExpr(ref l, _), &StmtExpr(ref r, _)) => is_exp_equal(cx, l, r, ignore_fn), + (&StmtSemi(ref l, _), &StmtSemi(ref r, _)) => is_exp_equal(cx, l, r, ignore_fn), _ => false, } } -pub fn is_exp_equal(cx: &LateContext, left: &Expr, right: &Expr) -> bool { +/// Check whether two blocks are the same. +/// See also `is_exp_equal`. +pub fn is_block_equal(cx: &LateContext, left: &Block, right: &Block, ignore_fn: bool) -> bool { + over(&left.stmts, &right.stmts, |l, r| is_stmt_equal(cx, l, r, ignore_fn)) && + both(&left.expr, &right.expr, |l, r| is_exp_equal(cx, l, r, ignore_fn)) +} + +/// Check whether two pattern are the same. +/// See also `is_exp_equal`. +pub fn is_pat_equal(cx: &LateContext, left: &Pat, right: &Pat, ignore_fn: bool) -> bool { + match (&left.node, &right.node) { + (&PatBox(ref l), &PatBox(ref r)) => { + is_pat_equal(cx, l, r, ignore_fn) + } + (&PatEnum(ref lp, ref la), &PatEnum(ref rp, ref ra)) => { + is_path_equal(lp, rp) && + both(la, ra, |l, r| { + over(l, r, |l, r| is_pat_equal(cx, l, r, ignore_fn)) + }) + } + (&PatIdent(ref lb, ref li, ref lp), &PatIdent(ref rb, ref ri, ref rp)) => { + lb == rb && li.node.name.as_str() == ri.node.name.as_str() && + both(lp, rp, |l, r| is_pat_equal(cx, l, r, ignore_fn)) + } + (&PatLit(ref l), &PatLit(ref r)) => { + is_exp_equal(cx, l, r, ignore_fn) + } + (&PatQPath(ref ls, ref lp), &PatQPath(ref rs, ref rp)) => { + is_qself_equal(ls, rs) && is_path_equal(lp, rp) + } + (&PatTup(ref l), &PatTup(ref r)) => { + over(l, r, |l, r| is_pat_equal(cx, l, r, ignore_fn)) + } + (&PatRange(ref ls, ref le), &PatRange(ref rs, ref re)) => { + is_exp_equal(cx, ls, rs, ignore_fn) && + is_exp_equal(cx, le, re, ignore_fn) + } + (&PatRegion(ref le, ref lm), &PatRegion(ref re, ref rm)) => { + lm == rm && is_pat_equal(cx, le, re, ignore_fn) + } + (&PatVec(ref ls, ref li, ref le), &PatVec(ref rs, ref ri, ref re)) => { + over(ls, rs, |l, r| is_pat_equal(cx, l, r, ignore_fn)) && + over(le, re, |l, r| is_pat_equal(cx, l, r, ignore_fn)) && + both(li, ri, |l, r| is_pat_equal(cx, l, r, ignore_fn)) + } + (&PatWild, &PatWild) => true, + _ => false, + } +} + +/// Check whether two expressions are the same. This is different from the operator `==` on +/// expression as this operator would compare true equality with ID and span. +/// If `ignore_fn` is true, never consider as equal fonction calls. +/// +/// Note that some expression kinds are not considered but could be added. +#[allow(cyclomatic_complexity)] // ok, it’s a big function, but mostly one big match with simples cases +pub fn is_exp_equal(cx: &LateContext, left: &Expr, right: &Expr, ignore_fn: bool) -> bool { if let (Some(l), Some(r)) = (constant(cx, left), constant(cx, right)) { if l == r { return true; } } + match (&left.node, &right.node) { (&ExprAddrOf(ref lmut, ref le), &ExprAddrOf(ref rmut, ref re)) => { - lmut == rmut && is_exp_equal(cx, le, re) + lmut == rmut && is_exp_equal(cx, le, re, ignore_fn) + } + (&ExprAgain(li), &ExprAgain(ri)) => { + both(&li, &ri, |l, r| l.node.name.as_str() == r.node.name.as_str()) + } + (&ExprAssign(ref ll, ref lr), &ExprAssign(ref rl, ref rr)) => { + is_exp_equal(cx, ll, rl, ignore_fn) && is_exp_equal(cx, lr, rr, ignore_fn) + } + (&ExprAssignOp(ref lo, ref ll, ref lr), &ExprAssignOp(ref ro, ref rl, ref rr)) => { + lo.node == ro.node && is_exp_equal(cx, ll, rl, ignore_fn) && is_exp_equal(cx, lr, rr, ignore_fn) + } + (&ExprBlock(ref l), &ExprBlock(ref r)) => { + is_block_equal(cx, l, r, ignore_fn) } (&ExprBinary(lop, ref ll, ref lr), &ExprBinary(rop, ref rl, ref rr)) => { - lop.node == rop.node && is_exp_equal(cx, ll, rl) && is_exp_equal(cx, lr, rr) + lop.node == rop.node && is_exp_equal(cx, ll, rl, ignore_fn) && is_exp_equal(cx, lr, rr, ignore_fn) + } + (&ExprBreak(li), &ExprBreak(ri)) => { + both(&li, &ri, |l, r| l.node.name.as_str() == r.node.name.as_str()) + } + (&ExprBox(ref l), &ExprBox(ref r)) => { + is_exp_equal(cx, l, r, ignore_fn) } (&ExprCall(ref lfun, ref largs), &ExprCall(ref rfun, ref rargs)) => { - is_exp_equal(cx, lfun, rfun) && is_exps_equal(cx, largs, rargs) + !ignore_fn && + is_exp_equal(cx, lfun, rfun, ignore_fn) && + is_exps_equal(cx, largs, rargs, ignore_fn) + } + (&ExprCast(ref lx, ref lt), &ExprCast(ref rx, ref rt)) => { + is_exp_equal(cx, lx, rx, ignore_fn) && is_cast_ty_equal(lt, rt) } - (&ExprCast(ref lx, ref lt), &ExprCast(ref rx, ref rt)) => is_exp_equal(cx, lx, rx) && is_cast_ty_equal(lt, rt), (&ExprField(ref lfexp, ref lfident), &ExprField(ref rfexp, ref rfident)) => { - lfident.node == rfident.node && is_exp_equal(cx, lfexp, rfexp) + lfident.node == rfident.node && is_exp_equal(cx, lfexp, rfexp, ignore_fn) } (&ExprIndex(ref la, ref li), &ExprIndex(ref ra, ref ri)) => { - is_exp_equal(cx, la, ra) && is_exp_equal(cx, li, ri) + is_exp_equal(cx, la, ra, ignore_fn) && is_exp_equal(cx, li, ri, ignore_fn) + } + (&ExprIf(ref lc, ref lt, ref le), &ExprIf(ref rc, ref rt, ref re)) => { + is_exp_equal(cx, lc, rc, ignore_fn) && + is_block_equal(cx, lt, rt, ignore_fn) && + both(le, re, |l, r| is_exp_equal(cx, l, r, ignore_fn)) } (&ExprLit(ref l), &ExprLit(ref r)) => l.node == r.node, + (&ExprMatch(ref le, ref la, ref ls), &ExprMatch(ref re, ref ra, ref rs)) => { + ls == rs && + is_exp_equal(cx, le, re, ignore_fn) && + over(la, ra, |l, r| { + is_exp_equal(cx, &l.body, &r.body, ignore_fn) && + both(&l.guard, &r.guard, |l, r| is_exp_equal(cx, l, r, ignore_fn)) && + over(&l.pats, &r.pats, |l, r| is_pat_equal(cx, l, r, ignore_fn)) + }) + } (&ExprMethodCall(ref lname, ref ltys, ref largs), &ExprMethodCall(ref rname, ref rtys, ref rargs)) => { // TODO: tys - lname.node == rname.node && ltys.is_empty() && rtys.is_empty() && is_exps_equal(cx, largs, rargs) + !ignore_fn && + lname.node == rname.node && + ltys.is_empty() && + rtys.is_empty() && + is_exps_equal(cx, largs, rargs, ignore_fn) + } + (&ExprRange(ref lb, ref le), &ExprRange(ref rb, ref re)) => { + both(lb, rb, |l, r| is_exp_equal(cx, l, r, ignore_fn)) && + both(le, re, |l, r| is_exp_equal(cx, l, r, ignore_fn)) + } + (&ExprRepeat(ref le, ref ll), &ExprRepeat(ref re, ref rl)) => { + is_exp_equal(cx, le, re, ignore_fn) && is_exp_equal(cx, ll, rl, ignore_fn) + } + (&ExprRet(ref l), &ExprRet(ref r)) => { + both(l, r, |l, r| is_exp_equal(cx, l, r, ignore_fn)) } (&ExprPath(ref lqself, ref lsubpath), &ExprPath(ref rqself, ref rsubpath)) => { both(lqself, rqself, is_qself_equal) && is_path_equal(lsubpath, rsubpath) } - (&ExprTup(ref ltup), &ExprTup(ref rtup)) => is_exps_equal(cx, ltup, rtup), + (&ExprTup(ref ltup), &ExprTup(ref rtup)) => is_exps_equal(cx, ltup, rtup, ignore_fn), (&ExprTupField(ref le, li), &ExprTupField(ref re, ri)) => { - li.node == ri.node && is_exp_equal(cx, le, re) + li.node == ri.node && is_exp_equal(cx, le, re, ignore_fn) } (&ExprUnary(lop, ref le), &ExprUnary(rop, ref re)) => { - lop == rop && is_exp_equal(cx, le, re) + lop == rop && is_exp_equal(cx, le, re, ignore_fn) + } + (&ExprVec(ref l), &ExprVec(ref r)) => is_exps_equal(cx, l, r, ignore_fn), + (&ExprWhile(ref lc, ref lb, ref ll), &ExprWhile(ref rc, ref rb, ref rl)) => { + is_exp_equal(cx, lc, rc, ignore_fn) && + is_block_equal(cx, lb, rb, ignore_fn) && + both(ll, rl, |l, r| l.name.as_str() == r.name.as_str()) } - (&ExprVec(ref l), &ExprVec(ref r)) => is_exps_equal(cx, l, r), _ => false, } } -fn is_exps_equal(cx: &LateContext, left: &[P], right: &[P]) -> bool { - over(left, right, |l, r| is_exp_equal(cx, l, r)) +fn is_exps_equal(cx: &LateContext, left: &[P], right: &[P], ignore_fn: bool) -> bool { + over(left, right, |l, r| is_exp_equal(cx, l, r, ignore_fn)) } fn is_path_equal(left: &Path, right: &Path) -> bool { @@ -650,20 +774,22 @@ fn is_path_equal(left: &Path, right: &Path) -> bool { left.global == right.global && over(&left.segments, &right.segments, - |l, r| l.identifier.name == r.identifier.name && l.parameters == r.parameters) + |l, r| l.identifier.name.as_str() == r.identifier.name.as_str() && l.parameters == r.parameters) } fn is_qself_equal(left: &QSelf, right: &QSelf) -> bool { left.ty.node == right.ty.node && left.position == right.position } +/// Check if two slices are equal as per `eq_fn`. pub fn over(left: &[X], right: &[X], mut eq_fn: F) -> bool where F: FnMut(&X, &X) -> bool { left.len() == right.len() && left.iter().zip(right).all(|(x, y)| eq_fn(x, y)) } -fn both(l: &Option, r: &Option, mut eq_fn: F) -> bool +/// Check if the two `Option`s are both `None` or some equal values as per `eq_fn`. +pub fn both(l: &Option, r: &Option, 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))) diff --git a/tests/compile-fail/copies.rs b/tests/compile-fail/copies.rs index 94c5c620f346..0f57b619ccc8 100755 --- a/tests/compile-fail/copies.rs +++ b/tests/compile-fail/copies.rs @@ -2,11 +2,15 @@ #![plugin(clippy)] #![allow(dead_code)] -#![deny(clippy)] +#![allow(let_and_return)] +#![allow(needless_return)] +#![allow(unused_variables)] +#![deny(if_same_then_else)] +#![deny(ifs_same_cond)] fn foo() -> bool { unimplemented!() } -fn if_same_then_else() { +fn if_same_then_else() -> &'static str { if true { //~ERROR this if has the same then and else blocks foo(); } @@ -41,6 +45,62 @@ fn if_same_then_else() { else { 42 }; + + if true { //~ERROR this if has the same then and else blocks + let bar = if true { + 42 + } + else { + 43 + }; + + while foo() { break; } + bar + 1; + } + else { + let bar = if true { + 42 + } + else { + 43 + }; + + while foo() { break; } + bar + 1; + } + + if true { //~ERROR this if has the same then and else blocks + match 42 { + 42 => (), + a if a > 0 => (), + 10...15 => (), + _ => (), + } + } + else { + match 42 { + 42 => (), + a if a > 0 => (), + 10...15 => (), + _ => (), + } + } + + if true { //~ERROR this if has the same then and else blocks + if let Some(a) = Some(42) {} + } + else { + if let Some(a) = Some(42) {} + } + + if true { //~ERROR this if has the same then and else blocks + let foo = ""; + return &foo[0..]; + } + else { + let foo = ""; + return &foo[0..]; + } } fn ifs_same_cond() { @@ -60,11 +120,15 @@ fn ifs_same_cond() { else if a == 1 { } - // Ok, maybe `foo` isn’t pure and this actually makes sense. But you should probably refactor - // this to make the intention clearer anyway. - if foo() { + let mut v = vec![1]; + if v.pop() == None { // ok, functions } - else if foo() { //~ERROR this if has the same condition as a previous if + else if v.pop() == None { + } + + if v.len() == 42 { // ok, functions + } + else if v.len() == 42 { } } diff --git a/tests/compile-fail/eq_op.rs b/tests/compile-fail/eq_op.rs index fc59c2739a2e..fe74d182da18 100644 --- a/tests/compile-fail/eq_op.rs +++ b/tests/compile-fail/eq_op.rs @@ -32,4 +32,9 @@ fn main() { // const folding 1 + 1 == 2; //~ERROR equal expressions 1 - 1 == 0; //~ERROR equal expressions + + let mut a = vec![1]; + a == a; //~ERROR equal expressions + 2*a.len() == 2*a.len(); // ok, functions + a.pop() == a.pop(); // ok, functions }