move 'match_type_parameter_diagnostic' to utils, get missed diagnostic item

Author: anall

clippy_lints/src/redundant_clone.rs

@@ -1,6 +1,6 @@
 use crate::utils::{
-    fn_has_unsatisfiable_preds, has_drop, is_copy, is_type_diagnostic_item, match_def_path, match_type, paths,
-    snippet_opt, span_lint_hir, span_lint_hir_and_then, walk_ptrs_ty_depth,
+    fn_has_unsatisfiable_preds, has_drop, is_copy, is_type_diagnostic_item, match_def_path, paths, snippet_opt,
+    span_lint_hir, span_lint_hir_and_then, walk_ptrs_ty_depth,
 };
 use if_chain::if_chain;
 use rustc_data_structures::{fx::FxHashMap, transitive_relation::TransitiveRelation};

clippy_lints/src/types.rs

@@ -23,7 +23,7 @@ use rustc_semver::RustcVersion;
 use rustc_session::{declare_lint_pass, declare_tool_lint, impl_lint_pass};
 use rustc_span::hygiene::{ExpnKind, MacroKind};
 use rustc_span::source_map::Span;
-use rustc_span::symbol::{sym, Symbol};
+use rustc_span::symbol::sym;
 use rustc_target::abi::LayoutOf;
 use rustc_target::spec::abi::Abi;
 use rustc_typeck::hir_ty_to_ty;
@@ -33,10 +33,10 @@ use crate::utils::paths;
 use crate::utils::sugg::Sugg;
 use crate::utils::{
     clip, comparisons, differing_macro_contexts, higher, in_constant, indent_of, int_bits, is_hir_ty_cfg_dependant,
-    is_type_diagnostic_item, last_path_segment, match_def_path, match_path, meets_msrv, method_chain_args,
-    multispan_sugg, numeric_literal::NumericLiteral, reindent_multiline, sext, snippet, snippet_opt,
-    snippet_with_applicability, snippet_with_macro_callsite, span_lint, span_lint_and_help, span_lint_and_sugg,
-    span_lint_and_then, unsext,
+    is_type_diagnostic_item, last_path_segment, match_def_path, match_path, match_type_parameter_diagnostic_item,
+    meets_msrv, method_chain_args, multispan_sugg, numeric_literal::NumericLiteral, reindent_multiline, sext, snippet,
+    snippet_opt, snippet_with_applicability, snippet_with_macro_callsite, span_lint, span_lint_and_help,
+    span_lint_and_sugg, span_lint_and_then, unsext,
 };
 
 declare_clippy_lint! {
@@ -307,33 +307,14 @@ fn match_type_parameter(cx: &LateContext<'_>, qpath: &QPath<'_>, path: &[&str])
     None
 }
 
-/// Checks if `qpath` has last segment with type parameter matching `diagnostic`
-fn match_type_parameter_diagnostic(cx: &LateContext<'_>, qpath: &QPath<'_>, diagnostic: Symbol) -> Option<Span> {
-    let last = last_path_segment(qpath);
-    if_chain! {
-        if let Some(ref params) = last.args;
-        if !params.parenthesized;
-        if let Some(ty) = params.args.iter().find_map(|arg| match arg {
-            GenericArg::Type(ty) => Some(ty),
-            _ => None,
-        });
-        if let TyKind::Path(ref qpath) = ty.kind;
-        if cx.qpath_res(qpath, ty.hir_id).opt_def_id() ==  cx.tcx.get_diagnostic_item(diagnostic);
-        then {
-            return Some(ty.span);
-        }
-    }
-    None
-}
-
 fn match_buffer_type(cx: &LateContext<'_>, qpath: &QPath<'_>) -> Option<&'static str> {
-    if match_type_parameter_diagnostic(cx, qpath, sym::string_type).is_some() {
+    if match_type_parameter_diagnostic_item(cx, qpath, sym::string_type).is_some() {
         return Some("str");
     }
-    if match_type_parameter_diagnostic(cx, qpath, sym::OsString).is_some() {
+    if match_type_parameter_diagnostic_item(cx, qpath, sym::OsString).is_some() {
         return Some("std::ffi::OsStr");
     }
-    if match_type_parameter_diagnostic(cx, qpath, sym::PathBuf).is_some() {
+    if match_type_parameter_diagnostic_item(cx, qpath, sym::PathBuf).is_some() {
         return Some("std::path::Path");
     }
     None
@@ -400,7 +381,7 @@ impl Types {
                             );
                             return; // don't recurse into the type
                         }
-                        if match_type_parameter_diagnostic(cx, qpath, sym::vec_type).is_some() {
+                        if match_type_parameter_diagnostic_item(cx, qpath, sym::vec_type).is_some() {
                             span_lint_and_help(
                                 cx,
                                 BOX_VEC,
@@ -412,7 +393,7 @@ impl Types {
                             return; // don't recurse into the type
                         }
                     } else if cx.tcx.is_diagnostic_item(sym::Rc, def_id) {
-                        if let Some(span) = match_type_parameter_diagnostic(cx, qpath, sym::Rc) {
+                        if let Some(span) = match_type_parameter_diagnostic_item(cx, qpath, sym::Rc) {
                             let mut applicability = Applicability::MachineApplicable;
                             span_lint_and_sugg(
                                 cx,
@@ -464,7 +445,7 @@ impl Types {
                             );
                             return; // don't recurse into the type
                         }
-                        if match_type_parameter_diagnostic(cx, qpath, sym::vec_type).is_some() {
+                        if match_type_parameter_diagnostic_item(cx, qpath, sym::vec_type).is_some() {
                             let vec_ty = match &last_path_segment(qpath).args.unwrap().args[0] {
                                 GenericArg::Type(ty) => match &ty.kind {
                                     TyKind::Path(qpath) => qpath,
@@ -517,7 +498,7 @@ impl Types {
                             );
                             return; // don't recurse into the type
                         }
-                        if match_type_parameter_diagnostic(cx, qpath, sym::vec_type).is_some() {
+                        if match_type_parameter_diagnostic_item(cx, qpath, sym::vec_type).is_some() {
                             let vec_ty = match &last_path_segment(qpath).args.unwrap().args[0] {
                                 GenericArg::Type(ty) => match &ty.kind {
                                     TyKind::Path(qpath) => qpath,
@@ -582,7 +563,7 @@ impl Types {
                             }
                         }
                     } else if cx.tcx.is_diagnostic_item(sym::option_type, def_id) {
-                        if match_type_parameter(cx, qpath, &paths::OPTION).is_some() {
+                        if match_type_parameter_diagnostic_item(cx, qpath, sym::option_type).is_some() {
                             span_lint(
                                 cx,
                                 OPTION_OPTION,

clippy_utils/src/lib.rs

@@ -253,6 +253,29 @@ pub fn is_diagnostic_assoc_item(cx: &LateContext<'_>, def_id: DefId, diag_item:
         .map_or(false, |assoc_def_id| cx.tcx.is_diagnostic_item(diag_item, assoc_def_id))
 }
 
+/// Checks if `qpath` has last segment with type parameter matching `diagnostic_item`
+pub fn match_type_parameter_diagnostic_item(
+    cx: &LateContext<'_>,
+    qpath: &QPath<'_>,
+    diagnostic_item: Symbol,
+) -> Option<Span> {
+    let last = last_path_segment(qpath);
+    if_chain! {
+        if let Some(ref params) = last.args;
+        if !params.parenthesized;
+        if let Some(ty) = params.args.iter().find_map(|arg| match arg {
+            rustc_hir::GenericArg::Type(ty) => Some(ty),
+            _ => None,
+        });
+        if let TyKind::Path(ref qpath) = ty.kind;
+        if cx.qpath_res(qpath, ty.hir_id).opt_def_id() == cx.tcx.get_diagnostic_item(diagnostic_item);
+        then {
+            return Some(ty.span);
+        }
+    }
+    None
+}
+
 /// Checks if an expression references a variable of the given name.
 pub fn match_var(expr: &Expr<'_>, var: Symbol) -> bool {
     if let ExprKind::Path(QPath::Resolved(None, ref path)) = expr.kind {