From 6589d794927451ed5d503b108e0e6900bbf91d3d Mon Sep 17 00:00:00 2001 From: Alex Macleod Date: Tue, 28 Mar 2023 21:28:57 +0000 Subject: [PATCH] Replace remaining usage of `FormatArgsExpn` --- clippy_lints/src/explicit_write.rs | 29 +- clippy_lints/src/format.rs | 91 ++- clippy_lints/src/format_impl.rs | 60 +- clippy_lints/src/methods/expect_fun_call.rs | 27 +- clippy_utils/src/lib.rs | 1 - clippy_utils/src/macros.rs | 727 +------------------- 6 files changed, 132 insertions(+), 803 deletions(-) diff --git a/clippy_lints/src/explicit_write.rs b/clippy_lints/src/explicit_write.rs index c0ea6f338a230..315df6c714ffc 100644 --- a/clippy_lints/src/explicit_write.rs +++ b/clippy_lints/src/explicit_write.rs @@ -1,5 +1,5 @@ use clippy_utils::diagnostics::span_lint_and_sugg; -use clippy_utils::macros::FormatArgsExpn; +use clippy_utils::macros::{find_format_args, format_args_inputs_span}; use clippy_utils::source::snippet_with_applicability; use clippy_utils::{is_expn_of, match_function_call, paths}; use if_chain::if_chain; @@ -8,7 +8,7 @@ use rustc_hir::def::Res; use rustc_hir::{BindingAnnotation, Block, BlockCheckMode, Expr, ExprKind, Node, PatKind, QPath, Stmt, StmtKind}; use rustc_lint::{LateContext, LateLintPass}; use rustc_session::{declare_lint_pass, declare_tool_lint}; -use rustc_span::sym; +use rustc_span::{sym, ExpnId}; declare_clippy_lint! { /// ### What it does @@ -43,23 +43,22 @@ declare_lint_pass!(ExplicitWrite => [EXPLICIT_WRITE]); impl<'tcx> LateLintPass<'tcx> for ExplicitWrite { fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) { - if_chain! { - // match call to unwrap - if let ExprKind::MethodCall(unwrap_fun, write_call, [], _) = expr.kind; - if unwrap_fun.ident.name == sym::unwrap; + // match call to unwrap + if let ExprKind::MethodCall(unwrap_fun, write_call, [], _) = expr.kind + && unwrap_fun.ident.name == sym::unwrap // match call to write_fmt - if let ExprKind::MethodCall(write_fun, write_recv, [write_arg], _) = look_in_block(cx, &write_call.kind); - if write_fun.ident.name == sym!(write_fmt); + && let ExprKind::MethodCall(write_fun, write_recv, [write_arg], _) = look_in_block(cx, &write_call.kind) + && write_fun.ident.name == sym!(write_fmt) // match calls to std::io::stdout() / std::io::stderr () - if let Some(dest_name) = if match_function_call(cx, write_recv, &paths::STDOUT).is_some() { + && let Some(dest_name) = if match_function_call(cx, write_recv, &paths::STDOUT).is_some() { Some("stdout") } else if match_function_call(cx, write_recv, &paths::STDERR).is_some() { Some("stderr") } else { None - }; - if let Some(format_args) = FormatArgsExpn::parse(cx, write_arg); - then { + } + { + find_format_args(cx, write_arg, ExpnId::root(), |format_args| { let calling_macro = // ordering is important here, since `writeln!` uses `write!` internally if is_expn_of(write_call.span, "writeln").is_some() { @@ -92,7 +91,7 @@ impl<'tcx> LateLintPass<'tcx> for ExplicitWrite { let mut applicability = Applicability::MachineApplicable; let inputs_snippet = snippet_with_applicability( cx, - format_args.inputs_span(), + format_args_inputs_span(format_args), "..", &mut applicability, ); @@ -104,8 +103,8 @@ impl<'tcx> LateLintPass<'tcx> for ExplicitWrite { "try this", format!("{prefix}{sugg_mac}!({inputs_snippet})"), applicability, - ) - } + ); + }); } } } diff --git a/clippy_lints/src/format.rs b/clippy_lints/src/format.rs index 8040938c6263e..d34d6e9279e4d 100644 --- a/clippy_lints/src/format.rs +++ b/clippy_lints/src/format.rs @@ -1,14 +1,13 @@ use clippy_utils::diagnostics::span_lint_and_sugg; -use clippy_utils::macros::{root_macro_call_first_node, FormatArgsExpn}; -use clippy_utils::source::snippet_with_context; +use clippy_utils::macros::{find_format_arg_expr, find_format_args, root_macro_call_first_node}; +use clippy_utils::source::{snippet_opt, snippet_with_context}; use clippy_utils::sugg::Sugg; -use if_chain::if_chain; +use rustc_ast::{FormatArgsPiece, FormatOptions, FormatTrait}; use rustc_errors::Applicability; use rustc_hir::{Expr, ExprKind}; use rustc_lint::{LateContext, LateLintPass}; use rustc_middle::ty; use rustc_session::{declare_lint_pass, declare_tool_lint}; -use rustc_span::symbol::kw; use rustc_span::{sym, Span}; declare_clippy_lint! { @@ -44,55 +43,53 @@ declare_lint_pass!(UselessFormat => [USELESS_FORMAT]); impl<'tcx> LateLintPass<'tcx> for UselessFormat { fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) { - let (format_args, call_site) = if_chain! { - if let Some(macro_call) = root_macro_call_first_node(cx, expr); - if cx.tcx.is_diagnostic_item(sym::format_macro, macro_call.def_id); - if let Some(format_args) = FormatArgsExpn::find_nested(cx, expr, macro_call.expn); - then { - (format_args, macro_call.span) - } else { - return - } - }; + let Some(macro_call) = root_macro_call_first_node(cx, expr) else { return }; + if !cx.tcx.is_diagnostic_item(sym::format_macro, macro_call.def_id) { + return; + } + + find_format_args(cx, expr, macro_call.expn, |format_args| { + let mut applicability = Applicability::MachineApplicable; + let call_site = macro_call.span; - let mut applicability = Applicability::MachineApplicable; - if format_args.args.is_empty() { - match *format_args.format_string.parts { - [] => span_useless_format_empty(cx, call_site, "String::new()".to_owned(), applicability), - [_] => { + match (format_args.arguments.all_args(), &format_args.template[..]) { + ([], []) => span_useless_format_empty(cx, call_site, "String::new()".to_owned(), applicability), + ([], [_]) => { // Simulate macro expansion, converting {{ and }} to { and }. - let s_expand = format_args.format_string.snippet.replace("{{", "{").replace("}}", "}"); + let Some(snippet) = snippet_opt(cx, format_args.span) else { return }; + let s_expand = snippet.replace("{{", "{").replace("}}", "}"); let sugg = format!("{s_expand}.to_string()"); span_useless_format(cx, call_site, sugg, applicability); }, - [..] => {}, - } - } else if let [arg] = &*format_args.args { - let value = arg.param.value; - if_chain! { - if format_args.format_string.parts == [kw::Empty]; - if arg.format.is_default(); - if match cx.typeck_results().expr_ty(value).peel_refs().kind() { - ty::Adt(adt, _) => Some(adt.did()) == cx.tcx.lang_items().string(), - ty::Str => true, - _ => false, - }; - then { - let is_new_string = match value.kind { - ExprKind::Binary(..) => true, - ExprKind::MethodCall(path, ..) => path.ident.name == sym::to_string, - _ => false, - }; - let sugg = if is_new_string { - snippet_with_context(cx, value.span, call_site.ctxt(), "..", &mut applicability).0.into_owned() - } else { - let sugg = Sugg::hir_with_context(cx, value, call_site.ctxt(), "", &mut applicability); - format!("{}.to_string()", sugg.maybe_par()) - }; - span_useless_format(cx, call_site, sugg, applicability); - } + ([arg], [piece]) => { + if let Ok(value) = find_format_arg_expr(expr, arg) + && let FormatArgsPiece::Placeholder(placeholder) = piece + && placeholder.format_trait == FormatTrait::Display + && placeholder.format_options == FormatOptions::default() + && match cx.typeck_results().expr_ty(value).peel_refs().kind() { + ty::Adt(adt, _) => Some(adt.did()) == cx.tcx.lang_items().string(), + ty::Str => true, + _ => false, + } + { + let is_new_string = match value.kind { + ExprKind::Binary(..) => true, + ExprKind::MethodCall(path, ..) => path.ident.name == sym::to_string, + _ => false, + }; + let sugg = if is_new_string { + snippet_with_context(cx, value.span, call_site.ctxt(), "..", &mut applicability).0.into_owned() + } else { + let sugg = Sugg::hir_with_context(cx, value, call_site.ctxt(), "", &mut applicability); + format!("{}.to_string()", sugg.maybe_par()) + }; + span_useless_format(cx, call_site, sugg, applicability); + + } + }, + _ => {}, } - }; + }); } } diff --git a/clippy_lints/src/format_impl.rs b/clippy_lints/src/format_impl.rs index ed1342a546543..e3ddbfb5981f8 100644 --- a/clippy_lints/src/format_impl.rs +++ b/clippy_lints/src/format_impl.rs @@ -1,11 +1,13 @@ use clippy_utils::diagnostics::{span_lint, span_lint_and_sugg}; -use clippy_utils::macros::{is_format_macro, root_macro_call_first_node, FormatArg, FormatArgsExpn}; +use clippy_utils::macros::{find_format_arg_expr, find_format_args, is_format_macro, root_macro_call_first_node}; use clippy_utils::{get_parent_as_impl, is_diag_trait_item, path_to_local, peel_ref_operators}; use if_chain::if_chain; +use rustc_ast::{FormatArgsPiece, FormatTrait}; use rustc_errors::Applicability; use rustc_hir::{Expr, ExprKind, Impl, ImplItem, ImplItemKind, QPath}; use rustc_lint::{LateContext, LateLintPass}; use rustc_session::{declare_tool_lint, impl_lint_pass}; +use rustc_span::Span; use rustc_span::{sym, symbol::kw, Symbol}; declare_clippy_lint! { @@ -89,7 +91,7 @@ declare_clippy_lint! { } #[derive(Clone, Copy)] -struct FormatTrait { +struct FormatTraitNames { /// e.g. `sym::Display` name: Symbol, /// `f` in `fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {}` @@ -99,7 +101,7 @@ struct FormatTrait { #[derive(Default)] pub struct FormatImpl { // Whether we are inside Display or Debug trait impl - None for neither - format_trait_impl: Option, + format_trait_impl: Option, } impl FormatImpl { @@ -161,43 +163,57 @@ fn check_to_string_in_display(cx: &LateContext<'_>, expr: &Expr<'_>) { } } -fn check_self_in_format_args<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>, impl_trait: FormatTrait) { +fn check_self_in_format_args<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>, impl_trait: FormatTraitNames) { // Check each arg in format calls - do we ever use Display on self (directly or via deref)? - if_chain! { - if let Some(outer_macro) = root_macro_call_first_node(cx, expr); - if let macro_def_id = outer_macro.def_id; - if let Some(format_args) = FormatArgsExpn::find_nested(cx, expr, outer_macro.expn); - if is_format_macro(cx, macro_def_id); - then { - for arg in format_args.args { - if arg.format.r#trait != impl_trait.name { - continue; + if let Some(outer_macro) = root_macro_call_first_node(cx, expr) + && let macro_def_id = outer_macro.def_id + && is_format_macro(cx, macro_def_id) + { + find_format_args(cx, expr, outer_macro.expn, |format_args| { + for piece in &format_args.template { + if let FormatArgsPiece::Placeholder(placeholder) = piece + && let trait_name = match placeholder.format_trait { + FormatTrait::Display => sym::Display, + FormatTrait::Debug => sym::Debug, + FormatTrait::LowerExp => sym!(LowerExp), + FormatTrait::UpperExp => sym!(UpperExp), + FormatTrait::Octal => sym!(Octal), + FormatTrait::Pointer => sym::Pointer, + FormatTrait::Binary => sym!(Binary), + FormatTrait::LowerHex => sym!(LowerHex), + FormatTrait::UpperHex => sym!(UpperHex), + } + && trait_name == impl_trait.name + && let Ok(index) = placeholder.argument.index + && let Some(arg) = format_args.arguments.all_args().get(index) + && let Ok(arg_expr) = find_format_arg_expr(expr, arg) + { + check_format_arg_self(cx, expr.span, arg_expr, impl_trait); } - check_format_arg_self(cx, expr, &arg, impl_trait); } - } + }); } } -fn check_format_arg_self(cx: &LateContext<'_>, expr: &Expr<'_>, arg: &FormatArg<'_>, impl_trait: FormatTrait) { +fn check_format_arg_self(cx: &LateContext<'_>, span: Span, arg: &Expr<'_>, impl_trait: FormatTraitNames) { // Handle multiple dereferencing of references e.g. &&self // Handle dereference of &self -> self that is equivalent (i.e. via *self in fmt() impl) // Since the argument to fmt is itself a reference: &self - let reference = peel_ref_operators(cx, arg.param.value); + let reference = peel_ref_operators(cx, arg); let map = cx.tcx.hir(); // Is the reference self? if path_to_local(reference).map(|x| map.name(x)) == Some(kw::SelfLower) { - let FormatTrait { name, .. } = impl_trait; + let FormatTraitNames { name, .. } = impl_trait; span_lint( cx, RECURSIVE_FORMAT_IMPL, - expr.span, + span, &format!("using `self` as `{name}` in `impl {name}` will cause infinite recursion"), ); } } -fn check_print_in_format_impl(cx: &LateContext<'_>, expr: &Expr<'_>, impl_trait: FormatTrait) { +fn check_print_in_format_impl(cx: &LateContext<'_>, expr: &Expr<'_>, impl_trait: FormatTraitNames) { if_chain! { if let Some(macro_call) = root_macro_call_first_node(cx, expr); if let Some(name) = cx.tcx.get_diagnostic_name(macro_call.def_id); @@ -227,7 +243,7 @@ fn check_print_in_format_impl(cx: &LateContext<'_>, expr: &Expr<'_>, impl_trait: } } -fn is_format_trait_impl(cx: &LateContext<'_>, impl_item: &ImplItem<'_>) -> Option { +fn is_format_trait_impl(cx: &LateContext<'_>, impl_item: &ImplItem<'_>) -> Option { if_chain! { if impl_item.ident.name == sym::fmt; if let ImplItemKind::Fn(_, body_id) = impl_item.kind; @@ -241,7 +257,7 @@ fn is_format_trait_impl(cx: &LateContext<'_>, impl_item: &ImplItem<'_>) -> Optio .and_then(|param| param.pat.simple_ident()) .map(|ident| ident.name); - Some(FormatTrait { + Some(FormatTraitNames { name, formatter_name, }) diff --git a/clippy_lints/src/methods/expect_fun_call.rs b/clippy_lints/src/methods/expect_fun_call.rs index a22285058d48e..92d21bb893262 100644 --- a/clippy_lints/src/methods/expect_fun_call.rs +++ b/clippy_lints/src/methods/expect_fun_call.rs @@ -1,5 +1,5 @@ use clippy_utils::diagnostics::span_lint_and_sugg; -use clippy_utils::macros::{root_macro_call_first_node, FormatArgsExpn}; +use clippy_utils::macros::{find_format_args, format_args_inputs_span, root_macro_call_first_node}; use clippy_utils::source::snippet_with_applicability; use clippy_utils::ty::{is_type_diagnostic_item, is_type_lang_item}; use rustc_errors::Applicability; @@ -136,18 +136,19 @@ pub(super) fn check<'tcx>( if !cx.tcx.is_diagnostic_item(sym::format_macro, macro_call.def_id) { return; } - let Some(format_args) = FormatArgsExpn::find_nested(cx, arg_root, macro_call.expn) else { return }; - let span = format_args.inputs_span(); - let sugg = snippet_with_applicability(cx, span, "..", &mut applicability); - span_lint_and_sugg( - cx, - EXPECT_FUN_CALL, - span_replace_word, - &format!("use of `{name}` followed by a function call"), - "try this", - format!("unwrap_or_else({closure_args} panic!({sugg}))"), - applicability, - ); + find_format_args(cx, arg_root, macro_call.expn, |format_args| { + let span = format_args_inputs_span(format_args); + let sugg = snippet_with_applicability(cx, span, "..", &mut applicability); + span_lint_and_sugg( + cx, + EXPECT_FUN_CALL, + span_replace_word, + &format!("use of `{name}` followed by a function call"), + "try this", + format!("unwrap_or_else({closure_args} panic!({sugg}))"), + applicability, + ); + }); return; } diff --git a/clippy_utils/src/lib.rs b/clippy_utils/src/lib.rs index 2e839fdf47288..f4af00599cd26 100644 --- a/clippy_utils/src/lib.rs +++ b/clippy_utils/src/lib.rs @@ -33,7 +33,6 @@ extern crate rustc_lexer; extern crate rustc_lint; extern crate rustc_middle; extern crate rustc_mir_dataflow; -extern crate rustc_parse_format; extern crate rustc_session; extern crate rustc_span; extern crate rustc_target; diff --git a/clippy_utils/src/macros.rs b/clippy_utils/src/macros.rs index b03e0d4a1ca59..62d388a5ece8d 100644 --- a/clippy_utils/src/macros.rs +++ b/clippy_utils/src/macros.rs @@ -1,24 +1,16 @@ #![allow(clippy::similar_names)] // `expr` and `expn` -use crate::source::snippet_opt; use crate::visitors::{for_each_expr, Descend}; use arrayvec::ArrayVec; -use itertools::{izip, Either, Itertools}; -use rustc_ast::ast::LitKind; use rustc_ast::{FormatArgs, FormatArgument, FormatPlaceholder}; use rustc_data_structures::fx::FxHashMap; -use rustc_hir::intravisit::{walk_expr, Visitor}; -use rustc_hir::{self as hir, Expr, ExprField, ExprKind, HirId, LangItem, Node, QPath, TyKind}; -use rustc_lexer::unescape::unescape_literal; -use rustc_lexer::{tokenize, unescape, LiteralKind, TokenKind}; +use rustc_hir::{self as hir, Expr, ExprKind, HirId, Node, QPath}; use rustc_lint::LateContext; -use rustc_parse_format::{self as rpf, Alignment}; use rustc_span::def_id::DefId; use rustc_span::hygiene::{self, MacroKind, SyntaxContext}; -use rustc_span::{sym, BytePos, ExpnData, ExpnId, ExpnKind, Pos, Span, SpanData, Symbol}; +use rustc_span::{sym, BytePos, ExpnData, ExpnId, ExpnKind, Span, Symbol}; use std::cell::RefCell; -use std::iter::{once, zip}; use std::ops::ControlFlow; use std::sync::atomic::{AtomicBool, Ordering}; @@ -226,11 +218,11 @@ pub enum PanicExpn<'a> { /// A single argument that implements `Display` - `panic!("{}", object)` Display(&'a Expr<'a>), /// Anything else - `panic!("error {}: {}", a, b)` - Format(FormatArgsExpn<'a>), + Format(&'a Expr<'a>), } impl<'a> PanicExpn<'a> { - pub fn parse(cx: &LateContext<'_>, expr: &'a Expr<'a>) -> Option { + pub fn parse(expr: &'a Expr<'a>) -> Option { let ExprKind::Call(callee, [arg, rest @ ..]) = &expr.kind else { return None }; let ExprKind::Path(QPath::Resolved(_, path)) = &callee.kind else { return None }; let result = match path.segments.last().unwrap().ident.as_str() { @@ -240,7 +232,7 @@ impl<'a> PanicExpn<'a> { let ExprKind::AddrOf(_, _, e) = &arg.kind else { return None }; Self::Display(e) }, - "panic_fmt" => Self::Format(FormatArgsExpn::parse(cx, arg)?), + "panic_fmt" => Self::Format(arg), // Since Rust 1.52, `assert_{eq,ne}` macros expand to use: // `core::panicking::assert_failed(.., left_val, right_val, None | Some(format_args!(..)));` "assert_failed" => { @@ -252,7 +244,7 @@ impl<'a> PanicExpn<'a> { // `msg_arg` is either `None` (no custom message) or `Some(format_args!(..))` (custom message) let msg_arg = &rest[2]; match msg_arg.kind { - ExprKind::Call(_, [fmt_arg]) => Self::Format(FormatArgsExpn::parse(cx, fmt_arg)?), + ExprKind::Call(_, [fmt_arg]) => Self::Format(fmt_arg), _ => Self::Empty, } }, @@ -304,7 +296,7 @@ fn find_assert_args_inner<'a, const N: usize>( let mut args = ArrayVec::new(); let panic_expn = for_each_expr(expr, |e| { if args.is_full() { - match PanicExpn::parse(cx, e) { + match PanicExpn::parse(e) { Some(expn) => ControlFlow::Break(expn), None => ControlFlow::Continue(Descend::Yes), } @@ -452,6 +444,21 @@ pub fn format_placeholder_format_span(placeholder: &FormatPlaceholder) -> Option )) } +/// Span covering the format string and values +/// +/// ```ignore +/// format("{}.{}", 10, 11) +/// // ^^^^^^^^^^^^^^^ +/// ``` +pub fn format_args_inputs_span(format_args: &FormatArgs) -> Span { + match format_args.arguments.explicit_args() { + [] => format_args.span, + [.., last] => format_args + .span + .to(hygiene::walk_chain(last.expr.span, format_args.span.ctxt())), + } +} + /// Returns the [`Span`] of the value at `index` extended to the previous comma, e.g. for the value /// `10` /// @@ -473,251 +480,6 @@ pub fn format_arg_removal_span(format_args: &FormatArgs, index: usize) -> Option Some(current.with_lo(prev.hi())) } -/// The format string doesn't exist in the HIR, so we reassemble it from source code -#[derive(Debug)] -pub struct FormatString { - /// Span of the whole format string literal, including `[r#]"`. - pub span: Span, - /// Snippet of the whole format string literal, including `[r#]"`. - pub snippet: String, - /// If the string is raw `r"..."`/`r#""#`, how many `#`s does it have on each side. - pub style: Option, - /// The unescaped value of the format string, e.g. `"val – {}"` for the literal - /// `"val \u{2013} {}"`. - pub unescaped: String, - /// The format string split by format args like `{..}`. - pub parts: Vec, -} - -impl FormatString { - fn new(cx: &LateContext<'_>, pieces: &Expr<'_>) -> Option { - // format_args!(r"a {} b \", 1); - // - // expands to - // - // ::core::fmt::Arguments::new_v1(&["a ", " b \\"], - // &[::core::fmt::ArgumentV1::new_display(&1)]); - // - // where `pieces` is the expression `&["a ", " b \\"]`. It has the span of `r"a {} b \"` - let span = pieces.span; - let snippet = snippet_opt(cx, span)?; - - let (inner, style) = match tokenize(&snippet).next()?.kind { - TokenKind::Literal { kind, .. } => { - let style = match kind { - LiteralKind::Str { .. } => None, - LiteralKind::RawStr { n_hashes: Some(n), .. } => Some(n.into()), - _ => return None, - }; - - let start = style.map_or(1, |n| 2 + n); - let end = snippet.len() - style.map_or(1, |n| 1 + n); - - (&snippet[start..end], style) - }, - _ => return None, - }; - - let mode = if style.is_some() { - unescape::Mode::RawStr - } else { - unescape::Mode::Str - }; - - let mut unescaped = String::with_capacity(inner.len()); - // Sometimes the original string comes from a macro which accepts a malformed string, such as in a - // #[display(""somestring)] attribute (accepted by the `displaythis` crate). Reconstructing the - // string from the span will not be possible, so we will just return None here. - let mut unparsable = false; - unescape_literal(inner, mode, &mut |_, ch| match ch { - Ok(ch) => unescaped.push(ch), - Err(e) if !e.is_fatal() => (), - Err(_) => unparsable = true, - }); - if unparsable { - return None; - } - - let mut parts = Vec::new(); - let _: Option = for_each_expr(pieces, |expr| { - if let ExprKind::Lit(lit) = &expr.kind - && let LitKind::Str(symbol, _) = lit.node - { - parts.push(symbol); - } - ControlFlow::Continue(()) - }); - - Some(Self { - span, - snippet, - style, - unescaped, - parts, - }) - } -} - -struct FormatArgsValues<'tcx> { - /// Values passed after the format string and implicit captures. `[1, z + 2, x]` for - /// `format!("{x} {} {}", 1, z + 2)`. - value_args: Vec<&'tcx Expr<'tcx>>, - /// Maps an `rt::v1::Argument::position` or an `rt::v1::Count::Param` to its index in - /// `value_args` - pos_to_value_index: Vec, - /// Used to check if a value is declared inline & to resolve `InnerSpan`s. - format_string_span: SpanData, -} - -impl<'tcx> FormatArgsValues<'tcx> { - fn new_empty(format_string_span: SpanData) -> Self { - Self { - value_args: Vec::new(), - pos_to_value_index: Vec::new(), - format_string_span, - } - } - - fn new(args: &'tcx Expr<'tcx>, format_string_span: SpanData) -> Self { - let mut pos_to_value_index = Vec::new(); - let mut value_args = Vec::new(); - let _: Option = for_each_expr(args, |expr| { - if expr.span.ctxt() == args.span.ctxt() { - // ArgumentV1::new_() - // ArgumentV1::from_usize() - if let ExprKind::Call(callee, [val]) = expr.kind - && let ExprKind::Path(QPath::TypeRelative(ty, _)) = callee.kind - && let TyKind::Path(QPath::LangItem(LangItem::FormatArgument, _, _)) = ty.kind - { - let val_idx = if val.span.ctxt() == expr.span.ctxt() - && let ExprKind::Field(_, field) = val.kind - && let Ok(idx) = field.name.as_str().parse() - { - // tuple index - idx - } else { - // assume the value expression is passed directly - pos_to_value_index.len() - }; - - pos_to_value_index.push(val_idx); - } - ControlFlow::Continue(Descend::Yes) - } else { - // assume that any expr with a differing span is a value - value_args.push(expr); - ControlFlow::Continue(Descend::No) - } - }); - - Self { - value_args, - pos_to_value_index, - format_string_span, - } - } -} - -/// The positions of a format argument's value, precision and width -/// -/// A position is an index into the second argument of `Arguments::new_v1[_formatted]` -#[derive(Debug, Default, Copy, Clone)] -struct ParamPosition { - /// The position stored in `rt::v1::Argument::position`. - value: usize, - /// The position stored in `rt::v1::FormatSpec::width` if it is a `Count::Param`. - width: Option, - /// The position stored in `rt::v1::FormatSpec::precision` if it is a `Count::Param`. - precision: Option, -} - -impl<'tcx> Visitor<'tcx> for ParamPosition { - fn visit_expr_field(&mut self, field: &'tcx ExprField<'tcx>) { - match field.ident.name { - sym::position => { - if let ExprKind::Lit(lit) = &field.expr.kind - && let LitKind::Int(pos, _) = lit.node - { - self.value = pos as usize; - } - }, - sym::precision => { - self.precision = parse_count(field.expr); - }, - sym::width => { - self.width = parse_count(field.expr); - }, - _ => walk_expr(self, field.expr), - } - } -} - -fn parse_count(expr: &Expr<'_>) -> Option { - // <::core::fmt::rt::v1::Count>::Param(1usize), - if let ExprKind::Call(ctor, [val]) = expr.kind - && let ExprKind::Path(QPath::TypeRelative(_, path)) = ctor.kind - && path.ident.name == sym::Param - && let ExprKind::Lit(lit) = &val.kind - && let LitKind::Int(pos, _) = lit.node - { - Some(pos as usize) - } else { - None - } -} - -/// Parses the `fmt` arg of `Arguments::new_v1_formatted(pieces, args, fmt, _)` -fn parse_rt_fmt<'tcx>(fmt_arg: &'tcx Expr<'tcx>) -> Option + 'tcx> { - if let ExprKind::AddrOf(.., array) = fmt_arg.kind - && let ExprKind::Array(specs) = array.kind - { - Some(specs.iter().map(|spec| { - if let ExprKind::Call(f, args) = spec.kind - && let ExprKind::Path(QPath::TypeRelative(ty, f)) = f.kind - && let TyKind::Path(QPath::LangItem(LangItem::FormatPlaceholder, _, _)) = ty.kind - && f.ident.name == sym::new - && let [position, _fill, _align, _flags, precision, width] = args - && let ExprKind::Lit(position) = &position.kind - && let LitKind::Int(position, _) = position.node { - ParamPosition { - value: position as usize, - width: parse_count(width), - precision: parse_count(precision), - } - } else { - ParamPosition::default() - } - })) - } else { - None - } -} - -/// `Span::from_inner`, but for `rustc_parse_format`'s `InnerSpan` -fn span_from_inner(base: SpanData, inner: rpf::InnerSpan) -> Span { - Span::new( - base.lo + BytePos::from_usize(inner.start), - base.lo + BytePos::from_usize(inner.end), - base.ctxt, - base.parent, - ) -} - -/// How a format parameter is used in the format string -#[derive(Debug, Copy, Clone, PartialEq, Eq)] -pub enum FormatParamKind { - /// An implicit parameter , such as `{}` or `{:?}`. - Implicit, - /// A parameter with an explicit number, e.g. `{1}`, `{0:?}`, or `{:.0$}` - Numbered, - /// A parameter with an asterisk precision. e.g. `{:.*}`. - Starred, - /// A named parameter with a named `value_arg`, such as the `x` in `format!("{x}", x = 1)`. - Named(Symbol), - /// An implicit named parameter, such as the `y` in `format!("{y}")`. - NamedInline(Symbol), -} - /// Where a format parameter is being used in the format string #[derive(Debug, Copy, Clone, PartialEq, Eq)] pub enum FormatParamUsage { @@ -729,451 +491,6 @@ pub enum FormatParamUsage { Precision, } -/// A `FormatParam` is any place in a `FormatArgument` that refers to a supplied value, e.g. -/// -/// ``` -/// let precision = 2; -/// format!("{:.precision$}", 0.1234); -/// ``` -/// -/// has two `FormatParam`s, a [`FormatParamKind::Implicit`] `.kind` with a `.value` of `0.1234` -/// and a [`FormatParamKind::NamedInline("precision")`] `.kind` with a `.value` of `2` -#[derive(Debug, Copy, Clone)] -pub struct FormatParam<'tcx> { - /// The expression this parameter refers to. - pub value: &'tcx Expr<'tcx>, - /// How this parameter refers to its `value`. - pub kind: FormatParamKind, - /// Where this format param is being used - argument/width/precision - pub usage: FormatParamUsage, - /// Span of the parameter, may be zero width. Includes the whitespace of implicit parameters. - /// - /// ```text - /// format!("{}, { }, {0}, {name}", ...); - /// ^ ~~ ~ ~~~~ - /// ``` - pub span: Span, -} - -impl<'tcx> FormatParam<'tcx> { - fn new( - mut kind: FormatParamKind, - usage: FormatParamUsage, - position: usize, - inner: rpf::InnerSpan, - values: &FormatArgsValues<'tcx>, - ) -> Option { - let value_index = *values.pos_to_value_index.get(position)?; - let value = *values.value_args.get(value_index)?; - let span = span_from_inner(values.format_string_span, inner); - - // if a param is declared inline, e.g. `format!("{x}")`, the generated expr's span points - // into the format string - if let FormatParamKind::Named(name) = kind && values.format_string_span.contains(value.span.data()) { - kind = FormatParamKind::NamedInline(name); - } - - Some(Self { - value, - kind, - usage, - span, - }) - } -} - -/// Used by [width](https://doc.rust-lang.org/std/fmt/#width) and -/// [precision](https://doc.rust-lang.org/std/fmt/#precision) specifiers. -#[derive(Debug, Copy, Clone)] -pub enum Count<'tcx> { - /// Specified with a literal number, stores the value. - Is(usize, Span), - /// Specified using `$` and `*` syntaxes. The `*` format is still considered to be - /// `FormatParamKind::Numbered`. - Param(FormatParam<'tcx>), - /// Not specified. - Implied(Option), -} - -impl<'tcx> Count<'tcx> { - fn new( - usage: FormatParamUsage, - count: rpf::Count<'_>, - position: Option, - inner: Option, - values: &FormatArgsValues<'tcx>, - ) -> Option { - let span = inner.map(|inner| span_from_inner(values.format_string_span, inner)); - - Some(match count { - rpf::Count::CountIs(val) => Self::Is(val, span?), - rpf::Count::CountIsName(name, _) => Self::Param(FormatParam::new( - FormatParamKind::Named(Symbol::intern(name)), - usage, - position?, - inner?, - values, - )?), - rpf::Count::CountIsParam(_) => Self::Param(FormatParam::new( - FormatParamKind::Numbered, - usage, - position?, - inner?, - values, - )?), - rpf::Count::CountIsStar(_) => Self::Param(FormatParam::new( - FormatParamKind::Starred, - usage, - position?, - inner?, - values, - )?), - rpf::Count::CountImplied => Self::Implied(span), - }) - } - - pub fn is_implied(self) -> bool { - matches!(self, Count::Implied(_)) - } - - pub fn param(self) -> Option> { - match self { - Count::Param(param) => Some(param), - _ => None, - } - } - - pub fn span(self) -> Option { - match self { - Count::Is(_, span) => Some(span), - Count::Param(param) => Some(param.span), - Count::Implied(span) => span, - } - } -} - -/// Specification for the formatting of an argument in the format string. See -/// for the precise meanings. -#[derive(Debug)] -pub struct FormatSpec<'tcx> { - /// Optionally specified character to fill alignment with. - pub fill: Option, - /// Optionally specified alignment. - pub align: Alignment, - /// Whether all flag options are set to default (no flags specified). - pub no_flags: bool, - /// Represents either the maximum width or the integer precision. - pub precision: Count<'tcx>, - /// The minimum width, will be padded according to `width`/`align` - pub width: Count<'tcx>, - /// The formatting trait used by the argument, e.g. `sym::Display` for `{}`, `sym::Debug` for - /// `{:?}`. - pub r#trait: Symbol, - pub trait_span: Option, -} - -impl<'tcx> FormatSpec<'tcx> { - fn new(spec: rpf::FormatSpec<'_>, positions: ParamPosition, values: &FormatArgsValues<'tcx>) -> Option { - Some(Self { - fill: spec.fill, - align: spec.align, - no_flags: spec.sign.is_none() && !spec.alternate && !spec.zero_pad && spec.debug_hex.is_none(), - precision: Count::new( - FormatParamUsage::Precision, - spec.precision, - positions.precision, - spec.precision_span, - values, - )?, - width: Count::new( - FormatParamUsage::Width, - spec.width, - positions.width, - spec.width_span, - values, - )?, - r#trait: match spec.ty { - "" => sym::Display, - "?" => sym::Debug, - "o" => sym!(Octal), - "x" => sym!(LowerHex), - "X" => sym!(UpperHex), - "p" => sym::Pointer, - "b" => sym!(Binary), - "e" => sym!(LowerExp), - "E" => sym!(UpperExp), - _ => return None, - }, - trait_span: spec - .ty_span - .map(|span| span_from_inner(values.format_string_span, span)), - }) - } - - /// Returns true if this format spec is unchanged from the default. e.g. returns true for `{}`, - /// `{foo}` and `{2}`, but false for `{:?}`, `{foo:5}` and `{3:.5}` - pub fn is_default(&self) -> bool { - self.r#trait == sym::Display && self.is_default_for_trait() - } - - /// Has no other formatting specifiers than setting the format trait. returns true for `{}`, - /// `{foo}`, `{:?}`, but false for `{foo:5}`, `{3:.5?}` - pub fn is_default_for_trait(&self) -> bool { - self.width.is_implied() && self.precision.is_implied() && self.align == Alignment::AlignUnknown && self.no_flags - } -} - -/// A format argument, such as `{}`, `{foo:?}`. -#[derive(Debug)] -pub struct FormatArg<'tcx> { - /// The parameter the argument refers to. - pub param: FormatParam<'tcx>, - /// How to format `param`. - pub format: FormatSpec<'tcx>, - /// span of the whole argument, `{..}`. - pub span: Span, -} - -/// A parsed `format_args!` expansion. -#[derive(Debug)] -pub struct FormatArgsExpn<'tcx> { - /// The format string literal. - pub format_string: FormatString, - /// The format arguments, such as `{:?}`. - pub args: Vec>, - /// Has an added newline due to `println!()`/`writeln!()`/etc. The last format string part will - /// include this added newline. - pub newline: bool, - /// Spans of the commas between the format string and explicit values, excluding any trailing - /// comma - /// - /// ```ignore - /// format!("..", 1, 2, 3,) - /// // ^ ^ ^ - /// ``` - comma_spans: Vec, - /// Explicit values passed after the format string, ignoring implicit captures. `[1, z + 2]` for - /// `format!("{x} {} {y}", 1, z + 2)`. - explicit_values: Vec<&'tcx Expr<'tcx>>, -} - -impl<'tcx> FormatArgsExpn<'tcx> { - /// Gets the spans of the commas inbetween the format string and explicit args, not including - /// any trailing comma - /// - /// ```ignore - /// format!("{} {}", a, b) - /// // ^ ^ - /// ``` - /// - /// Ensures that the format string and values aren't coming from a proc macro that sets the - /// output span to that of its input - fn comma_spans(cx: &LateContext<'_>, explicit_values: &[&Expr<'_>], fmt_span: Span) -> Option> { - // `format!("{} {} {c}", "one", "two", c = "three")` - // ^^^^^ ^^^^^ ^^^^^^^ - let value_spans = explicit_values - .iter() - .map(|val| hygiene::walk_chain(val.span, fmt_span.ctxt())); - - // `format!("{} {} {c}", "one", "two", c = "three")` - // ^^ ^^ ^^^^^^ - let between_spans = once(fmt_span) - .chain(value_spans) - .tuple_windows() - .map(|(start, end)| start.between(end)); - - let mut comma_spans = Vec::new(); - for between_span in between_spans { - let mut offset = 0; - let mut seen_comma = false; - - for token in tokenize(&snippet_opt(cx, between_span)?) { - match token.kind { - TokenKind::LineComment { .. } | TokenKind::BlockComment { .. } | TokenKind::Whitespace => {}, - TokenKind::Comma if !seen_comma => { - seen_comma = true; - - let base = between_span.data(); - comma_spans.push(Span::new( - base.lo + BytePos(offset), - base.lo + BytePos(offset + 1), - base.ctxt, - base.parent, - )); - }, - // named arguments, `start_val, name = end_val` - // ^^^^^^^^^ between_span - TokenKind::Ident | TokenKind::Eq if seen_comma => {}, - // An unexpected token usually indicates the format string or a value came from a proc macro output - // that sets the span of its output to an input, e.g. `println!(some_proc_macro!("input"), ..)` that - // emits a string literal with the span set to that of `"input"` - _ => return None, - } - offset += token.len; - } - - if !seen_comma { - return None; - } - } - - Some(comma_spans) - } - - pub fn parse(cx: &LateContext<'_>, expr: &'tcx Expr<'tcx>) -> Option { - let macro_name = macro_backtrace(expr.span) - .map(|macro_call| cx.tcx.item_name(macro_call.def_id)) - .find(|&name| matches!(name, sym::const_format_args | sym::format_args | sym::format_args_nl))?; - let newline = macro_name == sym::format_args_nl; - - // ::core::fmt::Arguments::new_const(pieces) - // ::core::fmt::Arguments::new_v1(pieces, args) - // ::core::fmt::Arguments::new_v1_formatted(pieces, args, fmt, _unsafe_arg) - if let ExprKind::Call(callee, [pieces, rest @ ..]) = expr.kind - && let ExprKind::Path(QPath::TypeRelative(ty, seg)) = callee.kind - && let TyKind::Path(QPath::LangItem(LangItem::FormatArguments, _, _)) = ty.kind - && matches!(seg.ident.as_str(), "new_const" | "new_v1" | "new_v1_formatted") - { - let format_string = FormatString::new(cx, pieces)?; - - let mut parser = rpf::Parser::new( - &format_string.unescaped, - format_string.style, - Some(format_string.snippet.clone()), - // `format_string.unescaped` does not contain the appended newline - false, - rpf::ParseMode::Format, - ); - - let parsed_args = parser - .by_ref() - .filter_map(|piece| match piece { - rpf::Piece::NextArgument(a) => Some(a), - rpf::Piece::String(_) => None, - }) - .collect_vec(); - if !parser.errors.is_empty() { - return None; - } - - let positions = if let Some(fmt_arg) = rest.get(1) { - // If the argument contains format specs, `new_v1_formatted(_, _, fmt, _)`, parse - // them. - - Either::Left(parse_rt_fmt(fmt_arg)?) - } else { - // If no format specs are given, the positions are in the given order and there are - // no `precision`/`width`s to consider. - - Either::Right((0..).map(|n| ParamPosition { - value: n, - width: None, - precision: None, - })) - }; - - let values = if let Some(args) = rest.first() { - FormatArgsValues::new(args, format_string.span.data()) - } else { - FormatArgsValues::new_empty(format_string.span.data()) - }; - - let args = izip!(positions, parsed_args, parser.arg_places) - .map(|(position, parsed_arg, arg_span)| { - Some(FormatArg { - param: FormatParam::new( - match parsed_arg.position { - rpf::Position::ArgumentImplicitlyIs(_) => FormatParamKind::Implicit, - rpf::Position::ArgumentIs(_) => FormatParamKind::Numbered, - // NamedInline is handled by `FormatParam::new()` - rpf::Position::ArgumentNamed(name) => FormatParamKind::Named(Symbol::intern(name)), - }, - FormatParamUsage::Argument, - position.value, - parsed_arg.position_span, - &values, - )?, - format: FormatSpec::new(parsed_arg.format, position, &values)?, - span: span_from_inner(values.format_string_span, arg_span), - }) - }) - .collect::>>()?; - - let mut explicit_values = values.value_args; - // remove values generated for implicitly captured vars - let len = explicit_values - .iter() - .take_while(|val| !format_string.span.contains(val.span)) - .count(); - explicit_values.truncate(len); - - let comma_spans = Self::comma_spans(cx, &explicit_values, format_string.span)?; - - Some(Self { - format_string, - args, - newline, - comma_spans, - explicit_values, - }) - } else { - None - } - } - - pub fn find_nested(cx: &LateContext<'tcx>, expr: &'tcx Expr<'tcx>, expn_id: ExpnId) -> Option { - for_each_expr(expr, |e| { - let e_ctxt = e.span.ctxt(); - if e_ctxt == expr.span.ctxt() { - ControlFlow::Continue(Descend::Yes) - } else if e_ctxt.outer_expn().is_descendant_of(expn_id) { - if let Some(args) = FormatArgsExpn::parse(cx, e) { - ControlFlow::Break(args) - } else { - ControlFlow::Continue(Descend::No) - } - } else { - ControlFlow::Continue(Descend::No) - } - }) - } - - /// Source callsite span of all inputs - pub fn inputs_span(&self) -> Span { - match *self.explicit_values { - [] => self.format_string.span, - [.., last] => self - .format_string - .span - .to(hygiene::walk_chain(last.span, self.format_string.span.ctxt())), - } - } - - /// Get the span of a value expanded to the previous comma, e.g. for the value `10` - /// - /// ```ignore - /// format("{}.{}", 10, 11) - /// // ^^^^ - /// ``` - pub fn value_with_prev_comma_span(&self, value_id: HirId) -> Option { - for (comma_span, value) in zip(&self.comma_spans, &self.explicit_values) { - if value.hir_id == value_id { - return Some(comma_span.to(hygiene::walk_chain(value.span, comma_span.ctxt()))); - } - } - - None - } - - /// Iterator of all format params, both values and those referenced by `width`/`precision`s. - pub fn params(&'tcx self) -> impl Iterator> { - self.args - .iter() - .flat_map(|arg| [Some(arg.param), arg.format.precision.param(), arg.format.width.param()]) - .flatten() - } -} - /// A node with a `HirId` and a `Span` pub trait HirNode { fn hir_id(&self) -> HirId;