From f49349bf333001166e3a215b7b2eb5b5cb1c9989 Mon Sep 17 00:00:00 2001 From: Takayuki Maeda Date: Sat, 6 Mar 2021 19:40:34 +0900 Subject: [PATCH] move or_fun_call to its own module --- clippy_lints/src/methods/mod.rs | 168 +---------------------- clippy_lints/src/methods/or_fun_call.rs | 173 ++++++++++++++++++++++++ 2 files changed, 178 insertions(+), 163 deletions(-) create mode 100644 clippy_lints/src/methods/or_fun_call.rs diff --git a/clippy_lints/src/methods/mod.rs b/clippy_lints/src/methods/mod.rs index 5f62942530c..857c1bf0ec0 100644 --- a/clippy_lints/src/methods/mod.rs +++ b/clippy_lints/src/methods/mod.rs @@ -33,6 +33,7 @@ mod ok_expect; mod option_as_ref_deref; mod option_map_or_none; mod option_map_unwrap_or; +mod or_fun_call; mod search_is_some; mod single_char_insert_string; mod single_char_pattern; @@ -66,12 +67,11 @@ use rustc_span::source_map::Span; use rustc_span::symbol::{sym, Symbol, SymbolStr}; use rustc_typeck::hir_ty_to_ty; -use crate::utils::eager_or_lazy::is_lazyness_candidate; use crate::utils::{ contains_return, contains_ty, get_trait_def_id, implements_trait, in_macro, is_copy, is_expn_of, - is_type_diagnostic_item, iter_input_pats, last_path_segment, match_def_path, match_qpath, match_type, method_calls, - method_chain_args, paths, return_ty, single_segment_path, snippet, snippet_with_applicability, - snippet_with_macro_callsite, span_lint, span_lint_and_help, span_lint_and_sugg, SpanlessEq, + is_type_diagnostic_item, iter_input_pats, match_def_path, match_qpath, method_calls, method_chain_args, paths, + return_ty, single_segment_path, snippet, snippet_with_applicability, span_lint, span_lint_and_help, + span_lint_and_sugg, SpanlessEq, }; declare_clippy_lint! { @@ -1778,7 +1778,7 @@ impl<'tcx> LateLintPass<'tcx> for Methods { } }, hir::ExprKind::MethodCall(ref method_call, ref method_span, ref args, _) => { - lint_or_fun_call(cx, expr, *method_span, &method_call.ident.as_str(), args); + or_fun_call::check(cx, expr, *method_span, &method_call.ident.as_str(), args); lint_expect_fun_call(cx, expr, *method_span, &method_call.ident.as_str(), args); let self_ty = cx.typeck_results().expr_ty_adjusted(&args[0]); @@ -1973,164 +1973,6 @@ impl<'tcx> LateLintPass<'tcx> for Methods { extract_msrv_attr!(LateContext); } -/// Checks for the `OR_FUN_CALL` lint. -#[allow(clippy::too_many_lines)] -fn lint_or_fun_call<'tcx>( - cx: &LateContext<'tcx>, - expr: &hir::Expr<'_>, - method_span: Span, - name: &str, - args: &'tcx [hir::Expr<'_>], -) { - /// Checks for `unwrap_or(T::new())` or `unwrap_or(T::default())`. - fn check_unwrap_or_default( - cx: &LateContext<'_>, - name: &str, - fun: &hir::Expr<'_>, - self_expr: &hir::Expr<'_>, - arg: &hir::Expr<'_>, - or_has_args: bool, - span: Span, - ) -> bool { - if_chain! { - if !or_has_args; - if name == "unwrap_or"; - if let hir::ExprKind::Path(ref qpath) = fun.kind; - let path = &*last_path_segment(qpath).ident.as_str(); - if ["default", "new"].contains(&path); - let arg_ty = cx.typeck_results().expr_ty(arg); - if let Some(default_trait_id) = get_trait_def_id(cx, &paths::DEFAULT_TRAIT); - if implements_trait(cx, arg_ty, default_trait_id, &[]); - - then { - let mut applicability = Applicability::MachineApplicable; - span_lint_and_sugg( - cx, - OR_FUN_CALL, - span, - &format!("use of `{}` followed by a call to `{}`", name, path), - "try this", - format!( - "{}.unwrap_or_default()", - snippet_with_applicability(cx, self_expr.span, "..", &mut applicability) - ), - applicability, - ); - - true - } else { - false - } - } - } - - /// Checks for `*or(foo())`. - #[allow(clippy::too_many_arguments)] - fn check_general_case<'tcx>( - cx: &LateContext<'tcx>, - name: &str, - method_span: Span, - self_expr: &hir::Expr<'_>, - arg: &'tcx hir::Expr<'_>, - span: Span, - // None if lambda is required - fun_span: Option, - ) { - // (path, fn_has_argument, methods, suffix) - static KNOW_TYPES: [(&[&str], bool, &[&str], &str); 4] = [ - (&paths::BTREEMAP_ENTRY, false, &["or_insert"], "with"), - (&paths::HASHMAP_ENTRY, false, &["or_insert"], "with"), - (&paths::OPTION, false, &["map_or", "ok_or", "or", "unwrap_or"], "else"), - (&paths::RESULT, true, &["or", "unwrap_or"], "else"), - ]; - - if let hir::ExprKind::MethodCall(ref path, _, ref args, _) = &arg.kind { - if path.ident.as_str() == "len" { - let ty = cx.typeck_results().expr_ty(&args[0]).peel_refs(); - - match ty.kind() { - ty::Slice(_) | ty::Array(_, _) => return, - _ => (), - } - - if is_type_diagnostic_item(cx, ty, sym::vec_type) { - return; - } - } - } - - if_chain! { - if KNOW_TYPES.iter().any(|k| k.2.contains(&name)); - - if is_lazyness_candidate(cx, arg); - if !contains_return(&arg); - - let self_ty = cx.typeck_results().expr_ty(self_expr); - - if let Some(&(_, fn_has_arguments, poss, suffix)) = - KNOW_TYPES.iter().find(|&&i| match_type(cx, self_ty, i.0)); - - if poss.contains(&name); - - then { - let macro_expanded_snipped; - let sugg: Cow<'_, str> = { - let (snippet_span, use_lambda) = match (fn_has_arguments, fun_span) { - (false, Some(fun_span)) => (fun_span, false), - _ => (arg.span, true), - }; - let snippet = { - let not_macro_argument_snippet = snippet_with_macro_callsite(cx, snippet_span, ".."); - if not_macro_argument_snippet == "vec![]" { - macro_expanded_snipped = snippet(cx, snippet_span, ".."); - match macro_expanded_snipped.strip_prefix("$crate::vec::") { - Some(stripped) => Cow::from(stripped), - None => macro_expanded_snipped - } - } - else { - not_macro_argument_snippet - } - }; - - if use_lambda { - let l_arg = if fn_has_arguments { "_" } else { "" }; - format!("|{}| {}", l_arg, snippet).into() - } else { - snippet - } - }; - let span_replace_word = method_span.with_hi(span.hi()); - span_lint_and_sugg( - cx, - OR_FUN_CALL, - span_replace_word, - &format!("use of `{}` followed by a function call", name), - "try this", - format!("{}_{}({})", name, suffix, sugg), - Applicability::HasPlaceholders, - ); - } - } - } - - if args.len() == 2 { - match args[1].kind { - hir::ExprKind::Call(ref fun, ref or_args) => { - let or_has_args = !or_args.is_empty(); - if !check_unwrap_or_default(cx, name, fun, &args[0], &args[1], or_has_args, expr.span) { - let fun_span = if or_has_args { None } else { Some(fun.span) }; - check_general_case(cx, name, method_span, &args[0], &args[1], expr.span, fun_span); - } - }, - hir::ExprKind::Index(..) | hir::ExprKind::MethodCall(..) => { - check_general_case(cx, name, method_span, &args[0], &args[1], expr.span, None); - }, - _ => {}, - } - } -} - /// Checks for the `EXPECT_FUN_CALL` lint. #[allow(clippy::too_many_lines)] fn lint_expect_fun_call( diff --git a/clippy_lints/src/methods/or_fun_call.rs b/clippy_lints/src/methods/or_fun_call.rs new file mode 100644 index 00000000000..5f7fc431d22 --- /dev/null +++ b/clippy_lints/src/methods/or_fun_call.rs @@ -0,0 +1,173 @@ +use crate::utils::eager_or_lazy::is_lazyness_candidate; +use crate::utils::{ + contains_return, get_trait_def_id, implements_trait, is_type_diagnostic_item, last_path_segment, match_type, paths, + snippet, snippet_with_applicability, snippet_with_macro_callsite, span_lint_and_sugg, +}; +use if_chain::if_chain; +use rustc_errors::Applicability; +use rustc_hir as hir; +use rustc_lint::LateContext; +use rustc_middle::ty; +use rustc_span::source_map::Span; +use rustc_span::symbol::sym; +use std::borrow::Cow; + +use super::OR_FUN_CALL; + +/// Checks for the `OR_FUN_CALL` lint. +#[allow(clippy::too_many_lines)] +pub(super) fn check<'tcx>( + cx: &LateContext<'tcx>, + expr: &hir::Expr<'_>, + method_span: Span, + name: &str, + args: &'tcx [hir::Expr<'_>], +) { + /// Checks for `unwrap_or(T::new())` or `unwrap_or(T::default())`. + fn check_unwrap_or_default( + cx: &LateContext<'_>, + name: &str, + fun: &hir::Expr<'_>, + self_expr: &hir::Expr<'_>, + arg: &hir::Expr<'_>, + or_has_args: bool, + span: Span, + ) -> bool { + if_chain! { + if !or_has_args; + if name == "unwrap_or"; + if let hir::ExprKind::Path(ref qpath) = fun.kind; + let path = &*last_path_segment(qpath).ident.as_str(); + if ["default", "new"].contains(&path); + let arg_ty = cx.typeck_results().expr_ty(arg); + if let Some(default_trait_id) = get_trait_def_id(cx, &paths::DEFAULT_TRAIT); + if implements_trait(cx, arg_ty, default_trait_id, &[]); + + then { + let mut applicability = Applicability::MachineApplicable; + span_lint_and_sugg( + cx, + OR_FUN_CALL, + span, + &format!("use of `{}` followed by a call to `{}`", name, path), + "try this", + format!( + "{}.unwrap_or_default()", + snippet_with_applicability(cx, self_expr.span, "..", &mut applicability) + ), + applicability, + ); + + true + } else { + false + } + } + } + + /// Checks for `*or(foo())`. + #[allow(clippy::too_many_arguments)] + fn check_general_case<'tcx>( + cx: &LateContext<'tcx>, + name: &str, + method_span: Span, + self_expr: &hir::Expr<'_>, + arg: &'tcx hir::Expr<'_>, + span: Span, + // None if lambda is required + fun_span: Option, + ) { + // (path, fn_has_argument, methods, suffix) + static KNOW_TYPES: [(&[&str], bool, &[&str], &str); 4] = [ + (&paths::BTREEMAP_ENTRY, false, &["or_insert"], "with"), + (&paths::HASHMAP_ENTRY, false, &["or_insert"], "with"), + (&paths::OPTION, false, &["map_or", "ok_or", "or", "unwrap_or"], "else"), + (&paths::RESULT, true, &["or", "unwrap_or"], "else"), + ]; + + if let hir::ExprKind::MethodCall(ref path, _, ref args, _) = &arg.kind { + if path.ident.as_str() == "len" { + let ty = cx.typeck_results().expr_ty(&args[0]).peel_refs(); + + match ty.kind() { + ty::Slice(_) | ty::Array(_, _) => return, + _ => (), + } + + if is_type_diagnostic_item(cx, ty, sym::vec_type) { + return; + } + } + } + + if_chain! { + if KNOW_TYPES.iter().any(|k| k.2.contains(&name)); + + if is_lazyness_candidate(cx, arg); + if !contains_return(&arg); + + let self_ty = cx.typeck_results().expr_ty(self_expr); + + if let Some(&(_, fn_has_arguments, poss, suffix)) = + KNOW_TYPES.iter().find(|&&i| match_type(cx, self_ty, i.0)); + + if poss.contains(&name); + + then { + let macro_expanded_snipped; + let sugg: Cow<'_, str> = { + let (snippet_span, use_lambda) = match (fn_has_arguments, fun_span) { + (false, Some(fun_span)) => (fun_span, false), + _ => (arg.span, true), + }; + let snippet = { + let not_macro_argument_snippet = snippet_with_macro_callsite(cx, snippet_span, ".."); + if not_macro_argument_snippet == "vec![]" { + macro_expanded_snipped = snippet(cx, snippet_span, ".."); + match macro_expanded_snipped.strip_prefix("$crate::vec::") { + Some(stripped) => Cow::from(stripped), + None => macro_expanded_snipped + } + } + else { + not_macro_argument_snippet + } + }; + + if use_lambda { + let l_arg = if fn_has_arguments { "_" } else { "" }; + format!("|{}| {}", l_arg, snippet).into() + } else { + snippet + } + }; + let span_replace_word = method_span.with_hi(span.hi()); + span_lint_and_sugg( + cx, + OR_FUN_CALL, + span_replace_word, + &format!("use of `{}` followed by a function call", name), + "try this", + format!("{}_{}({})", name, suffix, sugg), + Applicability::HasPlaceholders, + ); + } + } + } + + if args.len() == 2 { + match args[1].kind { + hir::ExprKind::Call(ref fun, ref or_args) => { + let or_has_args = !or_args.is_empty(); + if !check_unwrap_or_default(cx, name, fun, &args[0], &args[1], or_has_args, expr.span) { + let fun_span = if or_has_args { None } else { Some(fun.span) }; + check_general_case(cx, name, method_span, &args[0], &args[1], expr.span, fun_span); + } + }, + hir::ExprKind::Index(..) | hir::ExprKind::MethodCall(..) => { + check_general_case(cx, name, method_span, &args[0], &args[1], expr.span, None); + }, + _ => {}, + } + } +}