From 77005950f09d2f9ba54962bf5adc3f2bc3a7213f Mon Sep 17 00:00:00 2001
From: Arthur Carcano <arthur.carcano@ocamlpro.com>
Date: Fri, 25 Nov 2022 17:47:00 +0100
Subject: [PATCH 1/4] Implement masking in FileType comparison on Unix

Fixes: https://github.com/rust-lang/rust/issues/104900
---
 library/std/src/sys/unix/fs.rs | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/library/std/src/sys/unix/fs.rs b/library/std/src/sys/unix/fs.rs
index 37a49f2d78acd..382204d689318 100644
--- a/library/std/src/sys/unix/fs.rs
+++ b/library/std/src/sys/unix/fs.rs
@@ -332,11 +332,16 @@ pub struct FileTimes {
     modified: Option<SystemTime>,
 }
 
-#[derive(Copy, Clone, PartialEq, Eq, Hash, Debug)]
+#[derive(Copy, Clone, Eq, Hash, Debug)]
 pub struct FileType {
     mode: mode_t,
 }
 
+impl PartialEq for FileType {
+    fn eq(&self, other: &Self) -> bool {
+        self.masked() == other.masked()
+    }
+}
 #[derive(Debug)]
 pub struct DirBuilder {
     mode: mode_t,
@@ -550,6 +555,10 @@ impl FileType {
     pub fn is(&self, mode: mode_t) -> bool {
         self.mode & libc::S_IFMT == mode
     }
+
+    fn masked(&self) -> mode_t {
+        self.mode & libc::S_IFMT
+    }
 }
 
 impl FromInner<u32> for FilePermissions {

From 62590288621fe9c1fd9b379ed613538f7225f3eb Mon Sep 17 00:00:00 2001
From: Arthur Carcano <arthur.carcano@ocamlpro.com>
Date: Wed, 30 Nov 2022 23:31:42 +0100
Subject: [PATCH 2/4] Add test for regression for FileType equality

Cf: https://github.com/rust-lang/rust/issues/104900
---
 library/std/src/fs/tests.rs | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/library/std/src/fs/tests.rs b/library/std/src/fs/tests.rs
index b8959316de170..4748ac9d97ef8 100644
--- a/library/std/src/fs/tests.rs
+++ b/library/std/src/fs/tests.rs
@@ -1551,3 +1551,19 @@ fn hiberfil_sys() {
     fs::metadata(hiberfil).unwrap();
     assert_eq!(true, hiberfil.exists());
 }
+
+/// Test that two different ways of obtaining the FileType give the same result.
+/// Cf. https://github.com/rust-lang/rust/issues/104900
+#[test]
+fn test_eq_direntry_metadata() {
+    let tmpdir = tmpdir();
+    let file_path = tmpdir.join("file");
+    File::create(file_path).unwrap();
+    for e in fs::read_dir(tmpdir.path()).unwrap() {
+        let e = e.unwrap();
+        let p = e.path();
+        let ft1 = e.file_type().unwrap();
+        let ft2 = p.metadata().unwrap().file_type();
+        assert_eq!(ft1, ft2);
+    }
+}

From 4198d2975dd24322515f8894a3ac06e342aad183 Mon Sep 17 00:00:00 2001
From: Arthur Carcano <arthur.carcano@ocamlpro.com>
Date: Tue, 6 Dec 2022 10:35:34 +0100
Subject: [PATCH 3/4] Implement masking in FileType hashing on Unix

Commit 77005950f09d2f9ba54962bf5adc3f2bc3a7213f implemented masking of
FileType to fix an issue[^1] in the semantic of FileType comparison.
This commit introduces masking to Hash to maintain the invariant that
x == y => hash(x) == hash(y).

[^1]: https://github.com/rust-lang/rust/issues/104900
---
 library/std/src/sys/unix/fs.rs | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/library/std/src/sys/unix/fs.rs b/library/std/src/sys/unix/fs.rs
index 382204d689318..e464388069059 100644
--- a/library/std/src/sys/unix/fs.rs
+++ b/library/std/src/sys/unix/fs.rs
@@ -332,7 +332,7 @@ pub struct FileTimes {
     modified: Option<SystemTime>,
 }
 
-#[derive(Copy, Clone, Eq, Hash, Debug)]
+#[derive(Copy, Clone, Eq, Debug)]
 pub struct FileType {
     mode: mode_t,
 }
@@ -342,6 +342,13 @@ impl PartialEq for FileType {
         self.masked() == other.masked()
     }
 }
+
+impl core::hash::Hash for FileType {
+    fn hash<H: core::hash::Hasher>(&self, state: &mut H) {
+        self.masked().hash(state);
+    }
+}
+
 #[derive(Debug)]
 pub struct DirBuilder {
     mode: mode_t,

From 24cd863a3815f7ae7828c9f161a0b3f863218106 Mon Sep 17 00:00:00 2001
From: Arthur Carcano <arthur.carcano@ocamlpro.com>
Date: Fri, 9 Dec 2022 15:04:36 +0100
Subject: [PATCH 4/4] Replace hand-made masking by call to masked() method in
 FileType

---
 library/std/src/sys/unix/fs.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/library/std/src/sys/unix/fs.rs b/library/std/src/sys/unix/fs.rs
index e464388069059..fb8d06c66820c 100644
--- a/library/std/src/sys/unix/fs.rs
+++ b/library/std/src/sys/unix/fs.rs
@@ -560,7 +560,7 @@ impl FileType {
     }
 
     pub fn is(&self, mode: mode_t) -> bool {
-        self.mode & libc::S_IFMT == mode
+        self.masked() == mode
     }
 
     fn masked(&self) -> mode_t {