use rustc::lint::*;
-use syntax::codemap::mk_sp;
use syntax::ast;
use utils::{differing_macro_contexts, in_macro, snippet_opt, span_note_and_lint};
use syntax::ptr::P;
-/// **What it does:** This lint looks for use of the non-existent `=*`, `=!` and `=-` operators.
+/// **What it does:** Checks for use of the non-existent `=*`, `=!` and `=-`
+/// operators.
///
-/// **Why is this bad?** This is either a typo of `*=`, `!=` or `-=` or confusing.
+/// **Why is this bad?** This is either a typo of `*=`, `!=` or `-=` or
+/// confusing.
///
/// **Known problems:** None.
///
"suspicious formatting of `*=`, `-=` or `!=`"
}
-/// **What it does:** This lint checks for formatting of `else if`. It lints if the `else` and `if`
-/// are not on the same line or the `else` seems to be missing.
+/// **What it does:** Checks for formatting of `else if`. It lints if the `else`
+/// and `if` are not on the same line or the `else` seems to be missing.
///
-/// **Why is this bad?** This is probably some refactoring remnant, even if the code is correct, it
-/// might look confusing.
+/// **Why is this bad?** This is probably some refactoring remnant, even if the
+/// code is correct, it might look confusing.
///
/// **Known problems:** None.
///
"suspicious formatting of `else if`"
}
-#[derive(Copy,Clone)]
+/// **What it does:** Checks for possible missing comma in an array. It lints if
+/// an array element is a binary operator expression and it lies on two lines.
+///
+/// **Why is this bad?** This could lead to unexpected results.
+///
+/// **Known problems:** None.
+///
+/// **Example:**
+/// ```rust,ignore
+/// let a = &[
+/// -1, -2, -3 // <= no comma here
+/// -4, -5, -6
+/// ];
+/// ```
+declare_lint! {
+ pub POSSIBLE_MISSING_COMMA,
+ Warn,
+ "possible missing comma in array"
+}
+
+
+#[derive(Copy, Clone)]
pub struct Formatting;
impl LintPass for Formatting {
fn get_lints(&self) -> LintArray {
- lint_array![SUSPICIOUS_ASSIGNMENT_FORMATTING, SUSPICIOUS_ELSE_FORMATTING]
+ lint_array!(
+ SUSPICIOUS_ASSIGNMENT_FORMATTING,
+ SUSPICIOUS_ELSE_FORMATTING,
+ POSSIBLE_MISSING_COMMA
+ )
}
}
fn check_block(&mut self, cx: &EarlyContext, block: &ast::Block) {
for w in block.stmts.windows(2) {
match (&w[0].node, &w[1].node) {
- (&ast::StmtKind::Expr(ref first, _), &ast::StmtKind::Expr(ref second, _)) |
- (&ast::StmtKind::Expr(ref first, _), &ast::StmtKind::Semi(ref second, _)) => {
+ (&ast::StmtKind::Expr(ref first), &ast::StmtKind::Expr(ref second)) |
+ (&ast::StmtKind::Expr(ref first), &ast::StmtKind::Semi(ref second)) => {
check_consecutive_ifs(cx, first, second);
- }
+ },
_ => (),
}
}
-
- if let Some(ref expr) = block.expr {
- if let Some(ref stmt) = block.stmts.iter().last() {
- if let ast::StmtKind::Expr(ref first, _) = stmt.node {
- check_consecutive_ifs(cx, first, expr);
- }
- }
- }
}
fn check_expr(&mut self, cx: &EarlyContext, expr: &ast::Expr) {
check_assign(cx, expr);
check_else_if(cx, expr);
+ check_array(cx, expr);
}
}
/// Implementation of the `SUSPICIOUS_ASSIGNMENT_FORMATTING` lint.
fn check_assign(cx: &EarlyContext, expr: &ast::Expr) {
if let ast::ExprKind::Assign(ref lhs, ref rhs) = expr.node {
- if !differing_macro_contexts(lhs.span, rhs.span) && !in_macro(cx, lhs.span) {
- let eq_span = mk_sp(lhs.span.hi, rhs.span.lo);
-
+ if !differing_macro_contexts(lhs.span, rhs.span) && !in_macro(lhs.span) {
+ let eq_span = lhs.span.between(rhs.span);
if let ast::ExprKind::Unary(op, ref sub_rhs) = rhs.node {
if let Some(eq_snippet) = snippet_opt(cx, eq_span) {
let op = ast::UnOp::to_string(op);
- let eqop_span = mk_sp(lhs.span.hi, sub_rhs.span.lo);
+ let eqop_span = lhs.span.between(sub_rhs.span);
if eq_snippet.ends_with('=') {
- span_note_and_lint(cx,
- SUSPICIOUS_ASSIGNMENT_FORMATTING,
- eqop_span,
- &format!("this looks like you are trying to use `.. {op}= ..`, but you \
- really are doing `.. = ({op} ..)`",
- op = op),
- eqop_span,
- &format!("to remove this lint, use either `{op}=` or `= {op}`", op = op));
+ span_note_and_lint(
+ cx,
+ SUSPICIOUS_ASSIGNMENT_FORMATTING,
+ eqop_span,
+ &format!(
+ "this looks like you are trying to use `.. {op}= ..`, but you \
+ really are doing `.. = ({op} ..)`",
+ op = op
+ ),
+ eqop_span,
+ &format!("to remove this lint, use either `{op}=` or `= {op}`", op = op),
+ );
}
}
}
/// Implementation of the `SUSPICIOUS_ELSE_FORMATTING` lint for weird `else if`.
fn check_else_if(cx: &EarlyContext, expr: &ast::Expr) {
if let Some((then, &Some(ref else_))) = unsugar_if(expr) {
- if unsugar_if(else_).is_some() && !differing_macro_contexts(then.span, else_.span) && !in_macro(cx, then.span) {
- // this will be a span from the closing ‘}’ of the “then” block (excluding) to the
+ if unsugar_if(else_).is_some() && !differing_macro_contexts(then.span, else_.span) && !in_macro(then.span) {
+ // this will be a span from the closing ‘}’ of the “then” block (excluding) to
+ // the
// “if” of the “else if” block (excluding)
- let else_span = mk_sp(then.span.hi, else_.span.lo);
+ let else_span = then.span.between(else_.span);
// the snippet should look like " else \n " with maybe comments anywhere
// it’s bad when there is a ‘\n’ after the “else”
if let Some(else_snippet) = snippet_opt(cx, else_span) {
- let else_pos = else_snippet.find("else").expect("there must be a `else` here");
+ let else_pos = else_snippet
+ .find("else")
+ .expect("there must be a `else` here");
if else_snippet[else_pos..].contains('\n') {
- span_note_and_lint(cx,
- SUSPICIOUS_ELSE_FORMATTING,
- else_span,
- "this is an `else if` but the formatting might hide it",
- else_span,
- "to remove this lint, remove the `else` or remove the new line between `else` \
- and `if`");
+ span_note_and_lint(
+ cx,
+ SUSPICIOUS_ELSE_FORMATTING,
+ else_span,
+ "this is an `else if` but the formatting might hide it",
+ else_span,
+ "to remove this lint, remove the `else` or remove the new line between `else` \
+ and `if`",
+ );
+ }
+ }
+ }
+ }
+}
+
+/// Implementation of the `POSSIBLE_MISSING_COMMA` lint for array
+fn check_array(cx: &EarlyContext, expr: &ast::Expr) {
+ if let ast::ExprKind::Array(ref array) = expr.node {
+ for element in array {
+ if let ast::ExprKind::Binary(ref op, ref lhs, _) = element.node {
+ if !differing_macro_contexts(lhs.span, op.span) {
+ let space_span = lhs.span.between(op.span);
+ if let Some(space_snippet) = snippet_opt(cx, space_span) {
+ let lint_span = lhs.span.with_lo(lhs.span.hi());
+ if space_snippet.contains('\n') {
+ span_note_and_lint(
+ cx,
+ POSSIBLE_MISSING_COMMA,
+ lint_span,
+ "possibly missing a comma here",
+ lint_span,
+ "to remove this lint, add a comma or write the expr in a single line",
+ );
+ }
+ }
}
}
}
/// Implementation of the `SUSPICIOUS_ELSE_FORMATTING` lint for consecutive ifs.
fn check_consecutive_ifs(cx: &EarlyContext, first: &ast::Expr, second: &ast::Expr) {
- if !differing_macro_contexts(first.span, second.span) && !in_macro(cx, first.span) &&
- unsugar_if(first).is_some() && unsugar_if(second).is_some() {
+ if !differing_macro_contexts(first.span, second.span) && !in_macro(first.span) && unsugar_if(first).is_some()
+ && unsugar_if(second).is_some()
+ {
// where the else would be
- let else_span = mk_sp(first.span.hi, second.span.lo);
+ let else_span = first.span.between(second.span);
if let Some(else_snippet) = snippet_opt(cx, else_span) {
if !else_snippet.contains('\n') {
- span_note_and_lint(cx,
- SUSPICIOUS_ELSE_FORMATTING,
- else_span,
- "this looks like an `else if` but the `else` is missing",
- else_span,
- "to remove this lint, add the missing `else` or add a new line before the second \
- `if`");
+ span_note_and_lint(
+ cx,
+ SUSPICIOUS_ELSE_FORMATTING,
+ else_span,
+ "this looks like an `else if` but the `else` is missing",
+ else_span,
+ "to remove this lint, add the missing `else` or add a new line before the second \
+ `if`",
+ );
}
}
}
}
-/// Match `if` or `else if` expressions and return the `then` and `else` block.
+/// Match `if` or `if let` expressions and return the `then` and `else` block.
fn unsugar_if(expr: &ast::Expr) -> Option<(&P<ast::Block>, &Option<P<ast::Expr>>)> {
match expr.node {
- ast::ExprKind::If(_, ref then, ref else_) |
- ast::ExprKind::IfLet(_, _, ref then, ref else_) => Some((then, else_)),
+ ast::ExprKind::If(_, ref then, ref else_) | ast::ExprKind::IfLet(_, _, ref then, ref else_) => {
+ Some((then, else_))
+ },
_ => None,
}
}
projects / rust.git / blobdiff