Add path for display trait

Author: flip1995

clippy_lints/src/inherent_to_string.rs

@@ -120,8 +120,7 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for InherentToString {
 }
 
 fn show_lint(cx: &LateContext<'_, '_>, item: &ImplItem<'_>) {
-    let display_trait_id =
-        get_trait_def_id(cx, &["core", "fmt", "Display"]).expect("Failed to get trait ID of `Display`!");
+    let display_trait_id = get_trait_def_id(cx, &paths::DISPLAY_TRAIT).expect("Failed to get trait ID of `Display`!");
 
     // Get the real type of 'self'
     let fn_def_id = cx.tcx.hir().local_def_id(item.hir_id);

clippy_lints/src/utils/paths.rs

@@ -24,6 +24,7 @@ pub const DEFAULT_TRAIT_METHOD: [&str; 4] = ["core", "default", "Default", "defa
 pub const DEREF_MUT_TRAIT_METHOD: [&str; 5] = ["core", "ops", "deref", "DerefMut", "deref_mut"];
 pub const DEREF_TRAIT_METHOD: [&str; 5] = ["core", "ops", "deref", "Deref", "deref"];
 pub const DISPLAY_FMT_METHOD: [&str; 4] = ["core", "fmt", "Display", "fmt"];
+pub const DISPLAY_TRAIT: [&str; 3] = ["core", "fmt", "Display"];
 pub const DOUBLE_ENDED_ITERATOR: [&str; 4] = ["core", "iter", "traits", "DoubleEndedIterator"];
 pub const DROP: [&str; 3] = ["core", "mem", "drop"];
 pub const DROP_TRAIT: [&str; 4] = ["core", "ops", "drop", "Drop"];