Fix Ord, Eq and Hash implementation of panic::Location

Faster equality compare

Add tests

Add missing files for tests

1 files changed, 41 insertions, 1 deletions

diff --git a/library/core/src/panic/location.rs b/library/core/src/panic/location.rs
index 97227020885..6ef7d5a22a3 100644
--- a/library/core/src/panic/location.rs
+++ b/library/core/src/panic/location.rs
@@ -1,5 +1,7 @@
+use crate::cmp::Ordering;
 use crate::ffi::CStr;
 use crate::fmt;
+use crate::hash::{Hash, Hasher};
 use crate::marker::PhantomData;
 use crate::ptr::NonNull;
 
@@ -32,7 +34,7 @@ use crate::ptr::NonNull;
 /// Files are compared as strings, not `Path`, which could be unexpected.
 /// See [`Location::file`]'s documentation for more discussion.
 #[lang = "panic_location"]
-#[derive(Copy, Clone, Eq, Hash, Ord, PartialEq, PartialOrd)]
+#[derive(Copy, Clone)]
 #[stable(feature = "panic_hooks", since = "1.10.0")]
 pub struct Location<'a> {
     // A raw pointer is used rather than a reference because the pointer is valid for one more byte
@@ -45,6 +47,44 @@ pub struct Location<'a> {
 }
 
 #[stable(feature = "panic_hooks", since = "1.10.0")]
+impl PartialEq for Location<'_> {
+    fn eq(&self, other: &Self) -> bool {
+        // Compare col / line first as they're cheaper to compare and more likely to differ,
+        // while not impacting the result.
+        self.col == other.col && self.line == other.line && self.file() == other.file()
+    }
+}
+
+#[stable(feature = "panic_hooks", since = "1.10.0")]
+impl Eq for Location<'_> {}
+
+#[stable(feature = "panic_hooks", since = "1.10.0")]
+impl Ord for Location<'_> {
+    fn cmp(&self, other: &Self) -> Ordering {
+        self.file()
+            .cmp(other.file())
+            .then_with(|| self.line.cmp(&other.line))
+            .then_with(|| self.col.cmp(&other.col))
+    }
+}
+
+#[stable(feature = "panic_hooks", since = "1.10.0")]
+impl PartialOrd for Location<'_> {
+    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
+        Some(self.cmp(other))
+    }
+}
+
+#[stable(feature = "panic_hooks", since = "1.10.0")]
+impl Hash for Location<'_> {
+    fn hash<H: Hasher>(&self, state: &mut H) {
+        self.file().hash(state);
+        self.line.hash(state);
+        self.col.hash(state);
+    }
+}
+
+#[stable(feature = "panic_hooks", since = "1.10.0")]
 impl fmt::Debug for Location<'_> {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         f.debug_struct("Location")