-use crate::utils::{snippet_with_applicability, span_lint, span_lint_and_sugg, sym};
+use crate::utils::{snippet_with_applicability, span_lint, span_lint_and_sugg, span_lint_and_then};
use rustc::lint::{EarlyContext, EarlyLintPass, LintArray, LintPass};
use rustc::{declare_lint_pass, declare_tool_lint};
use rustc_errors::Applicability;
use std::borrow::Cow;
use syntax::ast::*;
use syntax::parse::{parser, token};
-use syntax::symbol::Symbol;
-use syntax::tokenstream::{TokenStream, TokenTree};
+use syntax::tokenstream::TokenStream;
+use syntax_pos::{BytePos, Span};
declare_clippy_lint! {
/// **What it does:** This lint warns when you use `println!("")` to
/// lint is to catch debugging remnants.
///
/// **Why is this bad?** The purpose of the `Debug` trait is to facilitate
- /// debugging Rust code. It should not be used in in user-facing output.
+ /// debugging Rust code. It should not be used in user-facing output.
///
/// **Example:**
/// ```rust
+ /// # let foo = "bar";
/// println!("{:?}", foo);
/// ```
pub USE_DEBUG,
impl EarlyLintPass for Write {
fn check_mac(&mut self, cx: &EarlyContext<'_>, mac: &Mac) {
- if mac.node.path == *sym::println {
+ if mac.path == sym!(println) {
span_lint(cx, PRINT_STDOUT, mac.span, "use of `println!`");
- if let Some(fmtstr) = check_tts(cx, &mac.node.tts, false).0 {
- if fmtstr == "" {
+ if let (Some(fmt_str), _) = check_tts(cx, &mac.tts, false) {
+ if fmt_str.contents.is_empty() {
span_lint_and_sugg(
cx,
PRINTLN_EMPTY_STRING,
);
}
}
- } else if mac.node.path == *sym::print {
+ } else if mac.path == sym!(print) {
span_lint(cx, PRINT_STDOUT, mac.span, "use of `print!`");
- if let (Some(fmtstr), _, is_raw) = check_tts(cx, &mac.node.tts, false) {
- if check_newlines(&fmtstr, is_raw) {
- span_lint(
+ if let (Some(fmt_str), _) = check_tts(cx, &mac.tts, false) {
+ if check_newlines(&fmt_str) {
+ span_lint_and_then(
cx,
PRINT_WITH_NEWLINE,
mac.span,
- "using `print!()` with a format string that ends in a \
- single newline, consider using `println!()` instead",
+ "using `print!()` with a format string that ends in a single newline",
+ |err| {
+ err.multipart_suggestion(
+ "use `println!` instead",
+ vec![
+ (mac.path.span, String::from("println")),
+ (fmt_str.newline_span(), String::new()),
+ ],
+ Applicability::MachineApplicable,
+ );
+ },
);
}
}
- } else if mac.node.path == *sym::write {
- if let (Some(fmtstr), _, is_raw) = check_tts(cx, &mac.node.tts, true) {
- if check_newlines(&fmtstr, is_raw) {
- span_lint(
+ } else if mac.path == sym!(write) {
+ if let (Some(fmt_str), _) = check_tts(cx, &mac.tts, true) {
+ if check_newlines(&fmt_str) {
+ span_lint_and_then(
cx,
WRITE_WITH_NEWLINE,
mac.span,
- "using `write!()` with a format string that ends in a \
- single newline, consider using `writeln!()` instead",
- );
+ "using `write!()` with a format string that ends in a single newline",
+ |err| {
+ err.multipart_suggestion(
+ "use `writeln!()` instead",
+ vec![
+ (mac.path.span, String::from("writeln")),
+ (fmt_str.newline_span(), String::new()),
+ ],
+ Applicability::MachineApplicable,
+ );
+ },
+ )
}
}
- } else if mac.node.path == *sym::writeln {
- let check_tts = check_tts(cx, &mac.node.tts, true);
- if let Some(fmtstr) = check_tts.0 {
- if fmtstr == "" {
+ } else if mac.path == sym!(writeln) {
+ if let (Some(fmt_str), expr) = check_tts(cx, &mac.tts, true) {
+ if fmt_str.contents.is_empty() {
let mut applicability = Applicability::MachineApplicable;
- let suggestion = check_tts.1.map_or_else(
+ let suggestion = expr.map_or_else(
move || {
applicability = Applicability::HasPlaceholders;
Cow::Borrowed("v")
}
}
+/// The arguments of a `print[ln]!` or `write[ln]!` invocation.
+struct FmtStr {
+ /// The contents of the format string (inside the quotes).
+ contents: String,
+ style: StrStyle,
+ /// The span of the format string, including quotes, the raw marker, and any raw hashes.
+ span: Span,
+}
+
+impl FmtStr {
+ /// Given a format string that ends in a newline and its span, calculates the span of the
+ /// newline.
+ fn newline_span(&self) -> Span {
+ let sp = self.span;
+
+ let newline_sp_hi = sp.hi()
+ - match self.style {
+ StrStyle::Cooked => BytePos(1),
+ StrStyle::Raw(hashes) => BytePos((1 + hashes).into()),
+ };
+
+ let newline_sp_len = if self.contents.ends_with('\n') {
+ BytePos(1)
+ } else if self.contents.ends_with(r"\n") {
+ BytePos(2)
+ } else {
+ panic!("expected format string to contain a newline");
+ };
+
+ sp.with_lo(newline_sp_hi - newline_sp_len).with_hi(newline_sp_hi)
+ }
+}
+
/// Checks the arguments of `print[ln]!` and `write[ln]!` calls. It will return a tuple of two
-/// options and a bool. The first part of the tuple is `format_str` of the macros. The second part
-/// of the tuple is in the `write[ln]!` case the expression the `format_str` should be written to.
-/// The final part is a boolean flag indicating if the string is a raw string.
+/// `Option`s. The first `Option` of the tuple is the macro's format string. It includes
+/// the contents of the string, whether it's a raw string, and the span of the literal in the
+/// source. The second `Option` in the tuple is, in the `write[ln]!` case, the expression the
+/// `format_str` should be written to.
///
/// Example:
///
/// ```
/// will return
/// ```rust,ignore
-/// (Some("string to write: {}"), Some(buf), false)
+/// (Some("string to write: {}"), Some(buf))
/// ```
-fn check_tts<'a>(cx: &EarlyContext<'a>, tts: &TokenStream, is_write: bool) -> (Option<String>, Option<Expr>, bool) {
+#[allow(clippy::too_many_lines)]
+fn check_tts<'a>(cx: &EarlyContext<'a>, tts: &TokenStream, is_write: bool) -> (Option<FmtStr>, Option<Expr>) {
use fmt_macros::*;
let tts = tts.clone();
- let mut is_raw = false;
- if let TokenStream(Some(tokens)) = &tts {
- for token in tokens.iter() {
- if let (TokenTree::Token(_, token::Token::Literal(lit, _)), _) = token {
- match lit {
- token::Lit::Str_(_) => break,
- token::Lit::StrRaw(_, _) => {
- is_raw = true;
- break;
- },
- _ => {},
- }
- }
- }
- }
- let mut parser = parser::Parser::new(&cx.sess.parse_sess, tts, None, false, false);
+
+ let mut parser = parser::Parser::new(&cx.sess.parse_sess, tts, None, false, false, None);
let mut expr: Option<Expr> = None;
if is_write {
expr = match parser.parse_expr().map_err(|mut err| err.cancel()) {
Ok(p) => Some(p.into_inner()),
- Err(_) => return (None, None, is_raw),
+ Err(_) => return (None, None),
};
// might be `writeln!(foo)`
if parser.expect(&token::Comma).map_err(|mut err| err.cancel()).is_err() {
- return (None, expr, is_raw);
+ return (None, expr);
}
}
- let fmtstr = match parser.parse_str().map_err(|mut err| err.cancel()) {
- Ok(token) => token.0.to_string(),
- Err(_) => return (None, expr, is_raw),
+ let (fmtstr, fmtstyle) = match parser.parse_str().map_err(|mut err| err.cancel()) {
+ Ok((fmtstr, fmtstyle)) => (fmtstr.to_string(), fmtstyle),
+ Err(_) => return (None, expr),
};
+ let fmtspan = parser.prev_span;
let tmp = fmtstr.clone();
let mut args = vec![];
let mut fmt_parser = Parser::new(&tmp, None, Vec::new(), false);
while let Some(piece) = fmt_parser.next() {
if !fmt_parser.errors.is_empty() {
- return (None, expr, is_raw);
+ return (None, expr);
}
if let Piece::NextArgument(arg) = piece {
if arg.format.ty == "?" {
align: AlignUnknown,
flags: 0,
precision: CountImplied,
+ precision_span: None,
width: CountImplied,
+ width_span: None,
ty: "",
};
if !parser.eat(&token::Comma) {
- return (Some(fmtstr), expr, is_raw);
+ return (
+ Some(FmtStr {
+ contents: fmtstr,
+ style: fmtstyle,
+ span: fmtspan,
+ }),
+ expr,
+ );
}
- let token_expr = match parser.parse_expr().map_err(|mut err| err.cancel()) {
- Ok(expr) => expr,
- Err(_) => return (Some(fmtstr), None, is_raw),
+ let token_expr = if let Ok(expr) = parser.parse_expr().map_err(|mut err| err.cancel()) {
+ expr
+ } else {
+ return (
+ Some(FmtStr {
+ contents: fmtstr,
+ style: fmtstyle,
+ span: fmtspan,
+ }),
+ None,
+ );
};
match &token_expr.node {
ExprKind::Lit(_) => {
match arg.position {
ArgumentImplicitlyIs(_) | ArgumentIs(_) => {},
ArgumentNamed(name) => {
- // FIXME: remove this interning if possible
- // https://github.com/rust-lang/rust/issues/60795
- if *p == Symbol::intern(name) {
+ if *p == name {
seen = true;
all_simple &= arg.format == SIMPLE;
}
}
}
-// Checks if `s` constains a single newline that terminates it
-// Literal and escaped newlines are both checked (only literal for raw strings)
-fn check_newlines(s: &str, is_raw: bool) -> bool {
+/// Checks if the format string constains a single newline that terminates it.
+///
+/// Literal and escaped newlines are both checked (only literal for raw strings).
+fn check_newlines(fmt_str: &FmtStr) -> bool {
+ let s = &fmt_str.contents;
+
if s.ends_with('\n') {
return true;
- } else if is_raw {
+ } else if let StrStyle::Raw(_) = fmt_str.style {
return false;
}
projects / rust.git / blobdiff