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-rw-r--r--src/tools/clippy/clippy_lints/src/write.rs709
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diff --git a/src/tools/clippy/clippy_lints/src/write.rs b/src/tools/clippy/clippy_lints/src/write.rs
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+++ b/src/tools/clippy/clippy_lints/src/write.rs
@@ -0,0 +1,709 @@
+use std::borrow::Cow;
+use std::iter;
+use std::ops::{Deref, Range};
+
+use clippy_utils::diagnostics::{span_lint, span_lint_and_sugg, span_lint_and_then};
+use clippy_utils::source::{snippet_opt, snippet_with_applicability};
+use rustc_ast::ast::{Expr, ExprKind, Impl, Item, ItemKind, MacCall, Path, StrLit, StrStyle};
+use rustc_ast::token::{self, LitKind};
+use rustc_ast::tokenstream::TokenStream;
+use rustc_errors::{Applicability, DiagnosticBuilder};
+use rustc_lexer::unescape::{self, EscapeError};
+use rustc_lint::{EarlyContext, EarlyLintPass, LintContext};
+use rustc_parse::parser;
+use rustc_session::{declare_tool_lint, impl_lint_pass};
+use rustc_span::symbol::{kw, Symbol};
+use rustc_span::{sym, BytePos, InnerSpan, Span, DUMMY_SP};
+
+declare_clippy_lint! {
+ /// ### What it does
+ /// This lint warns when you use `println!("")` to
+ /// print a newline.
+ ///
+ /// ### Why is this bad?
+ /// You should use `println!()`, which is simpler.
+ ///
+ /// ### Example
+ /// ```rust
+ /// println!("");
+ /// ```
+ ///
+ /// Use instead:
+ /// ```rust
+ /// println!();
+ /// ```
+ #[clippy::version = "pre 1.29.0"]
+ pub PRINTLN_EMPTY_STRING,
+ style,
+ "using `println!(\"\")` with an empty string"
+}
+
+declare_clippy_lint! {
+ /// ### What it does
+ /// This lint warns when you use `print!()` with a format
+ /// string that ends in a newline.
+ ///
+ /// ### Why is this bad?
+ /// You should use `println!()` instead, which appends the
+ /// newline.
+ ///
+ /// ### Example
+ /// ```rust
+ /// # let name = "World";
+ /// print!("Hello {}!\n", name);
+ /// ```
+ /// use println!() instead
+ /// ```rust
+ /// # let name = "World";
+ /// println!("Hello {}!", name);
+ /// ```
+ #[clippy::version = "pre 1.29.0"]
+ pub PRINT_WITH_NEWLINE,
+ style,
+ "using `print!()` with a format string that ends in a single newline"
+}
+
+declare_clippy_lint! {
+ /// ### What it does
+ /// Checks for printing on *stdout*. The purpose of this lint
+ /// is to catch debugging remnants.
+ ///
+ /// ### Why is this bad?
+ /// People often print on *stdout* while debugging an
+ /// application and might forget to remove those prints afterward.
+ ///
+ /// ### Known problems
+ /// * Only catches `print!` and `println!` calls.
+ /// * The lint level is unaffected by crate attributes. The level can still
+ /// be set for functions, modules and other items. To change the level for
+ /// the entire crate, please use command line flags. More information and a
+ /// configuration example can be found in [clippy#6610].
+ ///
+ /// [clippy#6610]: https://github.com/rust-lang/rust-clippy/issues/6610#issuecomment-977120558
+ ///
+ /// ### Example
+ /// ```rust
+ /// println!("Hello world!");
+ /// ```
+ #[clippy::version = "pre 1.29.0"]
+ pub PRINT_STDOUT,
+ restriction,
+ "printing on stdout"
+}
+
+declare_clippy_lint! {
+ /// ### What it does
+ /// Checks for printing on *stderr*. The purpose of this lint
+ /// is to catch debugging remnants.
+ ///
+ /// ### Why is this bad?
+ /// People often print on *stderr* while debugging an
+ /// application and might forget to remove those prints afterward.
+ ///
+ /// ### Known problems
+ /// * Only catches `eprint!` and `eprintln!` calls.
+ /// * The lint level is unaffected by crate attributes. The level can still
+ /// be set for functions, modules and other items. To change the level for
+ /// the entire crate, please use command line flags. More information and a
+ /// configuration example can be found in [clippy#6610].
+ ///
+ /// [clippy#6610]: https://github.com/rust-lang/rust-clippy/issues/6610#issuecomment-977120558
+ ///
+ /// ### Example
+ /// ```rust
+ /// eprintln!("Hello world!");
+ /// ```
+ #[clippy::version = "1.50.0"]
+ pub PRINT_STDERR,
+ restriction,
+ "printing on stderr"
+}
+
+declare_clippy_lint! {
+ /// ### What it does
+ /// Checks for use of `Debug` formatting. The purpose of this
+ /// 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 user-facing output.
+ ///
+ /// ### Example
+ /// ```rust
+ /// # let foo = "bar";
+ /// println!("{:?}", foo);
+ /// ```
+ #[clippy::version = "pre 1.29.0"]
+ pub USE_DEBUG,
+ restriction,
+ "use of `Debug`-based formatting"
+}
+
+declare_clippy_lint! {
+ /// ### What it does
+ /// This lint warns about the use of literals as `print!`/`println!` args.
+ ///
+ /// ### Why is this bad?
+ /// Using literals as `println!` args is inefficient
+ /// (c.f., https://github.com/matthiaskrgr/rust-str-bench) and unnecessary
+ /// (i.e., just put the literal in the format string)
+ ///
+ /// ### Known problems
+ /// Will also warn with macro calls as arguments that expand to literals
+ /// -- e.g., `println!("{}", env!("FOO"))`.
+ ///
+ /// ### Example
+ /// ```rust
+ /// println!("{}", "foo");
+ /// ```
+ /// use the literal without formatting:
+ /// ```rust
+ /// println!("foo");
+ /// ```
+ #[clippy::version = "pre 1.29.0"]
+ pub PRINT_LITERAL,
+ style,
+ "printing a literal with a format string"
+}
+
+declare_clippy_lint! {
+ /// ### What it does
+ /// This lint warns when you use `writeln!(buf, "")` to
+ /// print a newline.
+ ///
+ /// ### Why is this bad?
+ /// You should use `writeln!(buf)`, which is simpler.
+ ///
+ /// ### Example
+ /// ```rust
+ /// # use std::fmt::Write;
+ /// # let mut buf = String::new();
+ /// writeln!(buf, "");
+ /// ```
+ ///
+ /// Use instead:
+ /// ```rust
+ /// # use std::fmt::Write;
+ /// # let mut buf = String::new();
+ /// writeln!(buf);
+ /// ```
+ #[clippy::version = "pre 1.29.0"]
+ pub WRITELN_EMPTY_STRING,
+ style,
+ "using `writeln!(buf, \"\")` with an empty string"
+}
+
+declare_clippy_lint! {
+ /// ### What it does
+ /// This lint warns when you use `write!()` with a format
+ /// string that
+ /// ends in a newline.
+ ///
+ /// ### Why is this bad?
+ /// You should use `writeln!()` instead, which appends the
+ /// newline.
+ ///
+ /// ### Example
+ /// ```rust
+ /// # use std::fmt::Write;
+ /// # let mut buf = String::new();
+ /// # let name = "World";
+ /// write!(buf, "Hello {}!\n", name);
+ /// ```
+ ///
+ /// Use instead:
+ /// ```rust
+ /// # use std::fmt::Write;
+ /// # let mut buf = String::new();
+ /// # let name = "World";
+ /// writeln!(buf, "Hello {}!", name);
+ /// ```
+ #[clippy::version = "pre 1.29.0"]
+ pub WRITE_WITH_NEWLINE,
+ style,
+ "using `write!()` with a format string that ends in a single newline"
+}
+
+declare_clippy_lint! {
+ /// ### What it does
+ /// This lint warns about the use of literals as `write!`/`writeln!` args.
+ ///
+ /// ### Why is this bad?
+ /// Using literals as `writeln!` args is inefficient
+ /// (c.f., https://github.com/matthiaskrgr/rust-str-bench) and unnecessary
+ /// (i.e., just put the literal in the format string)
+ ///
+ /// ### Known problems
+ /// Will also warn with macro calls as arguments that expand to literals
+ /// -- e.g., `writeln!(buf, "{}", env!("FOO"))`.
+ ///
+ /// ### Example
+ /// ```rust
+ /// # use std::fmt::Write;
+ /// # let mut buf = String::new();
+ /// writeln!(buf, "{}", "foo");
+ /// ```
+ ///
+ /// Use instead:
+ /// ```rust
+ /// # use std::fmt::Write;
+ /// # let mut buf = String::new();
+ /// writeln!(buf, "foo");
+ /// ```
+ #[clippy::version = "pre 1.29.0"]
+ pub WRITE_LITERAL,
+ style,
+ "writing a literal with a format string"
+}
+
+#[derive(Default)]
+pub struct Write {
+ in_debug_impl: bool,
+}
+
+impl_lint_pass!(Write => [
+ PRINT_WITH_NEWLINE,
+ PRINTLN_EMPTY_STRING,
+ PRINT_STDOUT,
+ PRINT_STDERR,
+ USE_DEBUG,
+ PRINT_LITERAL,
+ WRITE_WITH_NEWLINE,
+ WRITELN_EMPTY_STRING,
+ WRITE_LITERAL
+]);
+
+impl EarlyLintPass for Write {
+ fn check_item(&mut self, _: &EarlyContext<'_>, item: &Item) {
+ if let ItemKind::Impl(box Impl {
+ of_trait: Some(trait_ref),
+ ..
+ }) = &item.kind
+ {
+ let trait_name = trait_ref
+ .path
+ .segments
+ .iter()
+ .last()
+ .expect("path has at least one segment")
+ .ident
+ .name;
+ if trait_name == sym::Debug {
+ self.in_debug_impl = true;
+ }
+ }
+ }
+
+ fn check_item_post(&mut self, _: &EarlyContext<'_>, _: &Item) {
+ self.in_debug_impl = false;
+ }
+
+ fn check_mac(&mut self, cx: &EarlyContext<'_>, mac: &MacCall) {
+ fn is_build_script(cx: &EarlyContext<'_>) -> bool {
+ // Cargo sets the crate name for build scripts to `build_script_build`
+ cx.sess()
+ .opts
+ .crate_name
+ .as_ref()
+ .map_or(false, |crate_name| crate_name == "build_script_build")
+ }
+
+ if mac.path == sym!(print) {
+ if !is_build_script(cx) {
+ span_lint(cx, PRINT_STDOUT, mac.span(), "use of `print!`");
+ }
+ self.lint_print_with_newline(cx, mac);
+ } else if mac.path == sym!(println) {
+ if !is_build_script(cx) {
+ span_lint(cx, PRINT_STDOUT, mac.span(), "use of `println!`");
+ }
+ self.lint_println_empty_string(cx, mac);
+ } else if mac.path == sym!(eprint) {
+ span_lint(cx, PRINT_STDERR, mac.span(), "use of `eprint!`");
+ self.lint_print_with_newline(cx, mac);
+ } else if mac.path == sym!(eprintln) {
+ span_lint(cx, PRINT_STDERR, mac.span(), "use of `eprintln!`");
+ self.lint_println_empty_string(cx, mac);
+ } else if mac.path == sym!(write) {
+ if let (Some(fmt_str), dest) = self.check_tts(cx, mac.args.inner_tokens(), true) {
+ if check_newlines(&fmt_str) {
+ let (nl_span, only_nl) = newline_span(&fmt_str);
+ let nl_span = match (dest, only_nl) {
+ // Special case of `write!(buf, "\n")`: Mark everything from the end of
+ // `buf` for removal so no trailing comma [`writeln!(buf, )`] remains.
+ (Some(dest_expr), true) => nl_span.with_lo(dest_expr.span.hi()),
+ _ => nl_span,
+ };
+ span_lint_and_then(
+ cx,
+ WRITE_WITH_NEWLINE,
+ mac.span(),
+ "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")), (nl_span, String::new())],
+ Applicability::MachineApplicable,
+ );
+ },
+ );
+ }
+ }
+ } else if mac.path == sym!(writeln) {
+ if let (Some(fmt_str), expr) = self.check_tts(cx, mac.args.inner_tokens(), true) {
+ if fmt_str.symbol == kw::Empty {
+ let mut applicability = Applicability::MachineApplicable;
+ let suggestion = if let Some(e) = expr {
+ snippet_with_applicability(cx, e.span, "v", &mut applicability)
+ } else {
+ applicability = Applicability::HasPlaceholders;
+ Cow::Borrowed("v")
+ };
+
+ span_lint_and_sugg(
+ cx,
+ WRITELN_EMPTY_STRING,
+ mac.span(),
+ format!("using `writeln!({}, \"\")`", suggestion).as_str(),
+ "replace it with",
+ format!("writeln!({})", suggestion),
+ applicability,
+ );
+ }
+ }
+ }
+ }
+}
+
+/// Given a format string that ends in a newline and its span, calculates the span of the
+/// newline, or the format string itself if the format string consists solely of a newline.
+/// Return this and a boolean indicating whether it only consisted of a newline.
+fn newline_span(fmtstr: &StrLit) -> (Span, bool) {
+ let sp = fmtstr.span;
+ let contents = fmtstr.symbol.as_str();
+
+ if contents == r"\n" {
+ return (sp, true);
+ }
+
+ let newline_sp_hi = sp.hi()
+ - match fmtstr.style {
+ StrStyle::Cooked => BytePos(1),
+ StrStyle::Raw(hashes) => BytePos((1 + hashes).into()),
+ };
+
+ let newline_sp_len = if contents.ends_with('\n') {
+ BytePos(1)
+ } else if 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), false)
+}
+
+/// Stores a list of replacement spans for each argument, but only if all the replacements used an
+/// empty format string.
+#[derive(Default)]
+struct SimpleFormatArgs {
+ unnamed: Vec<Vec<Span>>,
+ named: Vec<(Symbol, Vec<Span>)>,
+}
+impl SimpleFormatArgs {
+ fn get_unnamed(&self) -> impl Iterator<Item = &[Span]> {
+ self.unnamed.iter().map(|x| match x.as_slice() {
+ // Ignore the dummy span added from out of order format arguments.
+ [DUMMY_SP] => &[],
+ x => x,
+ })
+ }
+
+ fn get_named(&self, n: &Path) -> &[Span] {
+ self.named.iter().find(|x| *n == x.0).map_or(&[], |x| x.1.as_slice())
+ }
+
+ fn push(&mut self, arg: rustc_parse_format::Argument<'_>, span: Span) {
+ use rustc_parse_format::{
+ AlignUnknown, ArgumentImplicitlyIs, ArgumentIs, ArgumentNamed, CountImplied, FormatSpec,
+ };
+
+ const SIMPLE: FormatSpec<'_> = FormatSpec {
+ fill: None,
+ align: AlignUnknown,
+ flags: 0,
+ precision: CountImplied,
+ precision_span: None,
+ width: CountImplied,
+ width_span: None,
+ ty: "",
+ ty_span: None,
+ };
+
+ match arg.position {
+ ArgumentIs(n) | ArgumentImplicitlyIs(n) => {
+ if self.unnamed.len() <= n {
+ // Use a dummy span to mark all unseen arguments.
+ self.unnamed.resize_with(n, || vec![DUMMY_SP]);
+ if arg.format == SIMPLE {
+ self.unnamed.push(vec![span]);
+ } else {
+ self.unnamed.push(Vec::new());
+ }
+ } else {
+ let args = &mut self.unnamed[n];
+ match (args.as_mut_slice(), arg.format == SIMPLE) {
+ // A non-empty format string has been seen already.
+ ([], _) => (),
+ // Replace the dummy span, if it exists.
+ ([dummy @ DUMMY_SP], true) => *dummy = span,
+ ([_, ..], true) => args.push(span),
+ ([_, ..], false) => *args = Vec::new(),
+ }
+ }
+ },
+ ArgumentNamed(n) => {
+ let n = Symbol::intern(n);
+ if let Some(x) = self.named.iter_mut().find(|x| x.0 == n) {
+ match x.1.as_slice() {
+ // A non-empty format string has been seen already.
+ [] => (),
+ [_, ..] if arg.format == SIMPLE => x.1.push(span),
+ [_, ..] => x.1 = Vec::new(),
+ }
+ } else if arg.format == SIMPLE {
+ self.named.push((n, vec![span]));
+ } else {
+ self.named.push((n, Vec::new()));
+ }
+ },
+ };
+ }
+}
+
+impl Write {
+ /// Parses a format string into a collection of spans for each argument. This only keeps track
+ /// of empty format arguments. Will also lint usages of debug format strings outside of debug
+ /// impls.
+ fn parse_fmt_string(&self, cx: &EarlyContext<'_>, str_lit: &StrLit) -> Option<SimpleFormatArgs> {
+ use rustc_parse_format::{ParseMode, Parser, Piece};
+
+ let str_sym = str_lit.symbol_unescaped.as_str();
+ let style = match str_lit.style {
+ StrStyle::Cooked => None,
+ StrStyle::Raw(n) => Some(n as usize),
+ };
+
+ let mut parser = Parser::new(str_sym, style, snippet_opt(cx, str_lit.span), false, ParseMode::Format);
+ let mut args = SimpleFormatArgs::default();
+
+ while let Some(arg) = parser.next() {
+ let arg = match arg {
+ Piece::String(_) => continue,
+ Piece::NextArgument(arg) => arg,
+ };
+ let span = parser
+ .arg_places
+ .last()
+ .map_or(DUMMY_SP, |&x| str_lit.span.from_inner(InnerSpan::new(x.start, x.end)));
+
+ if !self.in_debug_impl && arg.format.ty == "?" {
+ // FIXME: modify rustc's fmt string parser to give us the current span
+ span_lint(cx, USE_DEBUG, span, "use of `Debug`-based formatting");
+ }
+
+ args.push(arg, span);
+ }
+
+ parser.errors.is_empty().then_some(args)
+ }
+
+ /// Checks the arguments of `print[ln]!` and `write[ln]!` calls. It will return a tuple of two
+ /// `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:
+ ///
+ /// Calling this function on
+ /// ```rust
+ /// # use std::fmt::Write;
+ /// # let mut buf = String::new();
+ /// # let something = "something";
+ /// writeln!(buf, "string to write: {}", something);
+ /// ```
+ /// will return
+ /// ```rust,ignore
+ /// (Some("string to write: {}"), Some(buf))
+ /// ```
+ fn check_tts<'a>(&self, cx: &EarlyContext<'a>, tts: TokenStream, is_write: bool) -> (Option<StrLit>, Option<Expr>) {
+ let mut parser = parser::Parser::new(&cx.sess().parse_sess, tts, false, None);
+ let expr = if is_write {
+ match parser
+ .parse_expr()
+ .map(rustc_ast::ptr::P::into_inner)
+ .map_err(DiagnosticBuilder::cancel)
+ {
+ // write!(e, ...)
+ Ok(p) if parser.eat(&token::Comma) => Some(p),
+ // write!(e) or error
+ e => return (None, e.ok()),
+ }
+ } else {
+ None
+ };
+
+ let fmtstr = match parser.parse_str_lit() {
+ Ok(fmtstr) => fmtstr,
+ Err(_) => return (None, expr),
+ };
+
+ let args = match self.parse_fmt_string(cx, &fmtstr) {
+ Some(args) => args,
+ None => return (Some(fmtstr), expr),
+ };
+
+ let lint = if is_write { WRITE_LITERAL } else { PRINT_LITERAL };
+ let mut unnamed_args = args.get_unnamed();
+ loop {
+ if !parser.eat(&token::Comma) {
+ return (Some(fmtstr), expr);
+ }
+
+ let comma_span = parser.prev_token.span;
+ let token_expr = if let Ok(expr) = parser.parse_expr().map_err(DiagnosticBuilder::cancel) {
+ expr
+ } else {
+ return (Some(fmtstr), None);
+ };
+ let (fmt_spans, lit) = match &token_expr.kind {
+ ExprKind::Lit(lit) => (unnamed_args.next().unwrap_or(&[]), lit),
+ ExprKind::Assign(lhs, rhs, _) => match (&lhs.kind, &rhs.kind) {
+ (ExprKind::Path(_, p), ExprKind::Lit(lit)) => (args.get_named(p), lit),
+ _ => continue,
+ },
+ _ => {
+ unnamed_args.next();
+ continue;
+ },
+ };
+
+ let replacement: String = match lit.token.kind {
+ LitKind::StrRaw(_) | LitKind::ByteStrRaw(_) if matches!(fmtstr.style, StrStyle::Raw(_)) => {
+ lit.token.symbol.as_str().replace('{', "{{").replace('}', "}}")
+ },
+ LitKind::Str | LitKind::ByteStr if matches!(fmtstr.style, StrStyle::Cooked) => {
+ lit.token.symbol.as_str().replace('{', "{{").replace('}', "}}")
+ },
+ LitKind::StrRaw(_)
+ | LitKind::Str
+ | LitKind::ByteStrRaw(_)
+ | LitKind::ByteStr
+ | LitKind::Integer
+ | LitKind::Float
+ | LitKind::Err => continue,
+ LitKind::Byte | LitKind::Char => match lit.token.symbol.as_str() {
+ "\"" if matches!(fmtstr.style, StrStyle::Cooked) => "\\\"",
+ "\"" if matches!(fmtstr.style, StrStyle::Raw(0)) => continue,
+ "\\\\" if matches!(fmtstr.style, StrStyle::Raw(_)) => "\\",
+ "\\'" => "'",
+ "{" => "{{",
+ "}" => "}}",
+ x if matches!(fmtstr.style, StrStyle::Raw(_)) && x.starts_with('\\') => continue,
+ x => x,
+ }
+ .into(),
+ LitKind::Bool => lit.token.symbol.as_str().deref().into(),
+ };
+
+ if !fmt_spans.is_empty() {
+ span_lint_and_then(
+ cx,
+ lint,
+ token_expr.span,
+ "literal with an empty format string",
+ |diag| {
+ diag.multipart_suggestion(
+ "try this",
+ iter::once((comma_span.to(token_expr.span), String::new()))
+ .chain(fmt_spans.iter().copied().zip(iter::repeat(replacement)))
+ .collect(),
+ Applicability::MachineApplicable,
+ );
+ },
+ );
+ }
+ }
+ }
+
+ fn lint_println_empty_string(&self, cx: &EarlyContext<'_>, mac: &MacCall) {
+ if let (Some(fmt_str), _) = self.check_tts(cx, mac.args.inner_tokens(), false) {
+ if fmt_str.symbol == kw::Empty {
+ let name = mac.path.segments[0].ident.name;
+ span_lint_and_sugg(
+ cx,
+ PRINTLN_EMPTY_STRING,
+ mac.span(),
+ &format!("using `{}!(\"\")`", name),
+ "replace it with",
+ format!("{}!()", name),
+ Applicability::MachineApplicable,
+ );
+ }
+ }
+ }
+
+ fn lint_print_with_newline(&self, cx: &EarlyContext<'_>, mac: &MacCall) {
+ if let (Some(fmt_str), _) = self.check_tts(cx, mac.args.inner_tokens(), false) {
+ if check_newlines(&fmt_str) {
+ let name = mac.path.segments[0].ident.name;
+ let suggested = format!("{}ln", name);
+ span_lint_and_then(
+ cx,
+ PRINT_WITH_NEWLINE,
+ mac.span(),
+ &format!("using `{}!()` with a format string that ends in a single newline", name),
+ |err| {
+ err.multipart_suggestion(
+ &format!("use `{}!` instead", suggested),
+ vec![(mac.path.span, suggested), (newline_span(&fmt_str).0, String::new())],
+ Applicability::MachineApplicable,
+ );
+ },
+ );
+ }
+ }
+ }
+}
+
+/// Checks if the format string contains a single newline that terminates it.
+///
+/// Literal and escaped newlines are both checked (only literal for raw strings).
+fn check_newlines(fmtstr: &StrLit) -> bool {
+ let mut has_internal_newline = false;
+ let mut last_was_cr = false;
+ let mut should_lint = false;
+
+ let contents = fmtstr.symbol.as_str();
+
+ let mut cb = |r: Range<usize>, c: Result<char, EscapeError>| {
+ let c = c.unwrap();
+
+ if r.end == contents.len() && c == '\n' && !last_was_cr && !has_internal_newline {
+ should_lint = true;
+ } else {
+ last_was_cr = c == '\r';
+ if c == '\n' {
+ has_internal_newline = true;
+ }
+ }
+ };
+
+ match fmtstr.style {
+ StrStyle::Cooked => unescape::unescape_literal(contents, unescape::Mode::Str, &mut cb),
+ StrStyle::Raw(_) => unescape::unescape_literal(contents, unescape::Mode::RawStr, &mut cb),
+ }
+
+ should_lint
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-07-26 07:27:00 +0000