From 9b3cc6c5b12d44686dcf166021ebac7121376607 Mon Sep 17 00:00:00 2001
From: Lovelin <100030865+lovelindhoni@users.noreply.github.com>
Date: Thu, 27 Feb 2025 00:08:02 +0530
Subject: [PATCH 01/10] feat: lint for public API sealed trait became unsealed

---
 src/lints/trait_sealed_becomes_unsealed.ron   | 54 +++++++++++++++
 src/query.rs                                  |  1 +
 .../new/Cargo.toml                            |  7 ++
 .../new/src/lib.rs                            | 16 +++++
 .../old/Cargo.toml                            |  7 ++
 .../old/src/lib.rs                            | 18 +++++
 .../trait_sealed_becomes_unsealed.snap        | 69 +++++++++++++++++++
 7 files changed, 172 insertions(+)
 create mode 100644 src/lints/trait_sealed_becomes_unsealed.ron
 create mode 100644 test_crates/trait_sealed_becomes_unsealed/new/Cargo.toml
 create mode 100644 test_crates/trait_sealed_becomes_unsealed/new/src/lib.rs
 create mode 100644 test_crates/trait_sealed_becomes_unsealed/old/Cargo.toml
 create mode 100644 test_crates/trait_sealed_becomes_unsealed/old/src/lib.rs
 create mode 100644 test_outputs/query_execution/trait_sealed_becomes_unsealed.snap

diff --git a/src/lints/trait_sealed_becomes_unsealed.ron b/src/lints/trait_sealed_becomes_unsealed.ron
new file mode 100644
index 00000000..58f0cebf
--- /dev/null
+++ b/src/lints/trait_sealed_becomes_unsealed.ron
@@ -0,0 +1,54 @@
+SemverQuery(
+    id: "trait_sealed_becomes_unsealed",
+    human_readable_name: "trait sealed becomes unsealed",
+    description: "A public sealed trait is unsealed, so users of this trait can implement it from now",
+    required_update: Minor,
+    lint_level: Deny,
+    reference_link: Some("https://rust-lang.github.io/api-guidelines/future-proofing.html#sealed-traits-protect-against-downstream-implementations-c-sealed"),  // TODO
+    query: r#"
+    {
+        CrateDiff {
+            baseline {
+                item {
+                    ... on Trait {
+                        visibility_limit @filter(op: "=", value: ["$public"]) @output
+                        public_api_sealed @filter(op: "=", value: ["$true"])
+
+                        importable_path {
+                            path @output @tag
+                            public_api @filter(op: "=", value: ["$true"])
+                        }
+                    }
+                }
+            }
+            current {
+                item {
+                    ... on Trait {
+                        visibility_limit @filter(op: "=", value: ["$public"])
+                        public_api_sealed @filter(op: "!=", value: ["$true"])
+                        name @output
+
+                        importable_path {
+                            path @filter(op: "=", value: ["%path"])
+                            public_api @filter(op: "=", value: ["$true"])
+                        }
+
+                        span_: span @optional {
+                            filename @output
+                            begin_line @output
+                            end_line @output
+                        }
+                    }
+                }
+            }
+        }
+    }
+  "#,
+    arguments: {
+        "public": "public",
+        "true": true,
+    },
+    error_message: "A publicly-visible sealed trait became unsealed, so now downstream crates are able to implement it",
+    per_result_error_template: Some("trait {{join \"::\" path}} in file {{span_filename}}:{{span_begin_line}}"),
+    witness: None,
+)
diff --git a/src/query.rs b/src/query.rs
index 1e8026ac..b2992493 100644
--- a/src/query.rs
+++ b/src/query.rs
@@ -1340,6 +1340,7 @@ add_lints!(
     trait_removed_supertrait,
     trait_requires_more_const_generic_params,
     trait_requires_more_generic_type_params,
+    trait_sealed_becomes_unsealed,
     trait_unsafe_added,
     trait_unsafe_removed,
     tuple_struct_to_plain_struct,
diff --git a/test_crates/trait_sealed_becomes_unsealed/new/Cargo.toml b/test_crates/trait_sealed_becomes_unsealed/new/Cargo.toml
new file mode 100644
index 00000000..5d8932ca
--- /dev/null
+++ b/test_crates/trait_sealed_becomes_unsealed/new/Cargo.toml
@@ -0,0 +1,7 @@
+[package]
+publish = false
+name = "trait_sealed_becomes_unsealed"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
diff --git a/test_crates/trait_sealed_becomes_unsealed/new/src/lib.rs b/test_crates/trait_sealed_becomes_unsealed/new/src/lib.rs
new file mode 100644
index 00000000..9c055295
--- /dev/null
+++ b/test_crates/trait_sealed_becomes_unsealed/new/src/lib.rs
@@ -0,0 +1,16 @@
+// This trait is public API sealed.
+pub trait PublicAPIToBeUnsealed {
+    type Hidden;
+}
+
+pub mod hidden_module {
+    /// This trait is public-API-sealed because implementing it
+    /// requires going outside the public API.
+    pub trait HiddenSealed {}
+
+    pub struct Token;
+}
+
+/// This trait is public-API-sealed since implementing it requires naming
+/// its non-public-API supertrait.
+pub trait HiddenSealedInherited: hidden_module::HiddenSealed {}
diff --git a/test_crates/trait_sealed_becomes_unsealed/old/Cargo.toml b/test_crates/trait_sealed_becomes_unsealed/old/Cargo.toml
new file mode 100644
index 00000000..5d8932ca
--- /dev/null
+++ b/test_crates/trait_sealed_becomes_unsealed/old/Cargo.toml
@@ -0,0 +1,7 @@
+[package]
+publish = false
+name = "trait_sealed_becomes_unsealed"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
diff --git a/test_crates/trait_sealed_becomes_unsealed/old/src/lib.rs b/test_crates/trait_sealed_becomes_unsealed/old/src/lib.rs
new file mode 100644
index 00000000..352e2d52
--- /dev/null
+++ b/test_crates/trait_sealed_becomes_unsealed/old/src/lib.rs
@@ -0,0 +1,18 @@
+// This trait is public API sealed.
+pub trait PublicAPIToBeUnsealed {
+    #[doc(hidden)]
+    type Hidden;
+}
+
+#[doc(hidden)]
+pub mod hidden_module {
+    /// This trait is public-API-sealed because implementing it
+    /// requires going outside the public API.
+    pub trait HiddenSealed {}
+
+    pub struct Token;
+}
+
+/// This trait is public-API-sealed since implementing it requires naming
+/// its non-public-API supertrait.
+pub trait HiddenSealedInherited: hidden_module::HiddenSealed {}
diff --git a/test_outputs/query_execution/trait_sealed_becomes_unsealed.snap b/test_outputs/query_execution/trait_sealed_becomes_unsealed.snap
new file mode 100644
index 00000000..faa62f8e
--- /dev/null
+++ b/test_outputs/query_execution/trait_sealed_becomes_unsealed.snap
@@ -0,0 +1,69 @@
+---
+source: src/query.rs
+expression: "&query_execution_results"
+---
+{
+  "./test_crates/trait_associated_type_marked_deprecated/": [
+    {
+      "name": String("PublicTraitWithHiddenType"),
+      "path": List([
+        String("trait_associated_type_marked_deprecated"),
+        String("PublicTraitWithHiddenType"),
+      ]),
+      "span_begin_line": Uint64(40),
+      "span_end_line": Uint64(44),
+      "span_filename": String("src/lib.rs"),
+      "visibility_limit": String("public"),
+    },
+  ],
+  "./test_crates/trait_method_added/": [
+    {
+      "name": String("WillGainMethodWithoutDefaultAndLoseSeal"),
+      "path": List([
+        String("trait_method_added"),
+        String("WillGainMethodWithoutDefaultAndLoseSeal"),
+      ]),
+      "span_begin_line": Uint64(43),
+      "span_end_line": Uint64(45),
+      "span_filename": String("src/lib.rs"),
+      "visibility_limit": String("public"),
+    },
+  ],
+  "./test_crates/trait_method_marked_deprecated/": [
+    {
+      "name": String("PublicTraitWithHiddenMethod"),
+      "path": List([
+        String("trait_method_marked_deprecated"),
+        String("PublicTraitWithHiddenMethod"),
+      ]),
+      "span_begin_line": Uint64(47),
+      "span_end_line": Uint64(51),
+      "span_filename": String("src/lib.rs"),
+      "visibility_limit": String("public"),
+    },
+  ],
+  "./test_crates/trait_sealed_becomes_unsealed/": [
+    {
+      "name": String("PublicAPIToBeUnsealed"),
+      "path": List([
+        String("trait_sealed_becomes_unsealed"),
+        String("PublicAPIToBeUnsealed"),
+      ]),
+      "span_begin_line": Uint64(2),
+      "span_end_line": Uint64(4),
+      "span_filename": String("src/lib.rs"),
+      "visibility_limit": String("public"),
+    },
+    {
+      "name": String("HiddenSealedInherited"),
+      "path": List([
+        String("trait_sealed_becomes_unsealed"),
+        String("HiddenSealedInherited"),
+      ]),
+      "span_begin_line": Uint64(16),
+      "span_end_line": Uint64(16),
+      "span_filename": String("src/lib.rs"),
+      "visibility_limit": String("public"),
+    },
+  ],
+}

From 3fd4dc56ee73f6d341957249d48d7d34ee254a18 Mon Sep 17 00:00:00 2001
From: Lovelin <100030865+lovelindhoni@users.noreply.github.com>
Date: Thu, 27 Feb 2025 10:29:57 +0530
Subject: [PATCH 02/10] feat: more examples on test_crates

---
 src/lints/trait_sealed_becomes_unsealed.ron   |  2 +-
 .../new/src/lib.rs                            | 24 ++++++++++
 .../old/src/lib.rs                            | 24 ++++++++++
 .../trait_sealed_becomes_unsealed.snap        | 44 +++++++++++++++++++
 4 files changed, 93 insertions(+), 1 deletion(-)

diff --git a/src/lints/trait_sealed_becomes_unsealed.ron b/src/lints/trait_sealed_becomes_unsealed.ron
index 58f0cebf..1f2db480 100644
--- a/src/lints/trait_sealed_becomes_unsealed.ron
+++ b/src/lints/trait_sealed_becomes_unsealed.ron
@@ -3,7 +3,7 @@ SemverQuery(
     human_readable_name: "trait sealed becomes unsealed",
     description: "A public sealed trait is unsealed, so users of this trait can implement it from now",
     required_update: Minor,
-    lint_level: Deny,
+    lint_level: Warn,
     reference_link: Some("https://rust-lang.github.io/api-guidelines/future-proofing.html#sealed-traits-protect-against-downstream-implementations-c-sealed"),  // TODO
     query: r#"
     {
diff --git a/test_crates/trait_sealed_becomes_unsealed/new/src/lib.rs b/test_crates/trait_sealed_becomes_unsealed/new/src/lib.rs
index 9c055295..87e59a38 100644
--- a/test_crates/trait_sealed_becomes_unsealed/new/src/lib.rs
+++ b/test_crates/trait_sealed_becomes_unsealed/new/src/lib.rs
@@ -14,3 +14,27 @@ pub mod hidden_module {
 /// This trait is public-API-sealed since implementing it requires naming
 /// its non-public-API supertrait.
 pub trait HiddenSealedInherited: hidden_module::HiddenSealed {}
+
+/// This trait is public-API-sealed because its method's return type is doc-hidden,
+/// so external implementers would have to name a non-public-API type to write the impl.
+pub trait MethodReturnHiddenSealed {
+    fn method(&self) -> hidden_module::Token;
+}
+
+/// This trait is public-API-sealed transitively because of its supertrait.
+pub trait TransitivelyHiddenSealed: HiddenSealedInherited {}
+
+/// This trait is public-API-sealed, since `Self: hidden_module::HiddenSealed`
+/// still requires that `Self` implement a public-API-sealed trait,
+/// even though the public-API-sealed trait isn't *exactly* a supertrait.
+pub trait HiddenSealedWithWhereSelfBound
+where
+    Self: hidden_module::HiddenSealed,
+{
+}
+
+/// This trait is public-API-sealed because its method's argument type is doc-hidden,
+/// so external implementers would have to name a non-public-API type to write the impl.
+pub trait MethodHiddenSealed {
+    fn method(&self, token: hidden_module::Token);
+}
diff --git a/test_crates/trait_sealed_becomes_unsealed/old/src/lib.rs b/test_crates/trait_sealed_becomes_unsealed/old/src/lib.rs
index 352e2d52..574e9374 100644
--- a/test_crates/trait_sealed_becomes_unsealed/old/src/lib.rs
+++ b/test_crates/trait_sealed_becomes_unsealed/old/src/lib.rs
@@ -16,3 +16,27 @@ pub mod hidden_module {
 /// This trait is public-API-sealed since implementing it requires naming
 /// its non-public-API supertrait.
 pub trait HiddenSealedInherited: hidden_module::HiddenSealed {}
+
+/// This trait is public-API-sealed because its method's return type is doc-hidden,
+/// so external implementers would have to name a non-public-API type to write the impl.
+pub trait MethodReturnHiddenSealed {
+    fn method(&self) -> hidden_module::Token;
+}
+
+/// This trait is public-API-sealed transitively because of its supertrait.
+pub trait TransitivelyHiddenSealed: HiddenSealedInherited {}
+
+/// This trait is public-API-sealed, since `Self: hidden_module::HiddenSealed`
+/// still requires that `Self` implement a public-API-sealed trait,
+/// even though the public-API-sealed trait isn't *exactly* a supertrait.
+pub trait HiddenSealedWithWhereSelfBound
+where
+    Self: hidden_module::HiddenSealed,
+{
+}
+
+/// This trait is public-API-sealed because its method's argument type is doc-hidden,
+/// so external implementers would have to name a non-public-API type to write the impl.
+pub trait MethodHiddenSealed {
+    fn method(&self, token: hidden_module::Token);
+}
diff --git a/test_outputs/query_execution/trait_sealed_becomes_unsealed.snap b/test_outputs/query_execution/trait_sealed_becomes_unsealed.snap
index faa62f8e..f66e15ba 100644
--- a/test_outputs/query_execution/trait_sealed_becomes_unsealed.snap
+++ b/test_outputs/query_execution/trait_sealed_becomes_unsealed.snap
@@ -65,5 +65,49 @@ expression: "&query_execution_results"
       "span_filename": String("src/lib.rs"),
       "visibility_limit": String("public"),
     },
+    {
+      "name": String("MethodReturnHiddenSealed"),
+      "path": List([
+        String("trait_sealed_becomes_unsealed"),
+        String("MethodReturnHiddenSealed"),
+      ]),
+      "span_begin_line": Uint64(20),
+      "span_end_line": Uint64(22),
+      "span_filename": String("src/lib.rs"),
+      "visibility_limit": String("public"),
+    },
+    {
+      "name": String("TransitivelyHiddenSealed"),
+      "path": List([
+        String("trait_sealed_becomes_unsealed"),
+        String("TransitivelyHiddenSealed"),
+      ]),
+      "span_begin_line": Uint64(25),
+      "span_end_line": Uint64(25),
+      "span_filename": String("src/lib.rs"),
+      "visibility_limit": String("public"),
+    },
+    {
+      "name": String("HiddenSealedWithWhereSelfBound"),
+      "path": List([
+        String("trait_sealed_becomes_unsealed"),
+        String("HiddenSealedWithWhereSelfBound"),
+      ]),
+      "span_begin_line": Uint64(30),
+      "span_end_line": Uint64(34),
+      "span_filename": String("src/lib.rs"),
+      "visibility_limit": String("public"),
+    },
+    {
+      "name": String("MethodHiddenSealed"),
+      "path": List([
+        String("trait_sealed_becomes_unsealed"),
+        String("MethodHiddenSealed"),
+      ]),
+      "span_begin_line": Uint64(38),
+      "span_end_line": Uint64(40),
+      "span_filename": String("src/lib.rs"),
+      "visibility_limit": String("public"),
+    },
   ],
 }

From bd51869f2ca27514b7f3ef218f237fe633c8845f Mon Sep 17 00:00:00 2001
From: Lovelin <100030865+lovelindhoni@users.noreply.github.com>
Date: Thu, 27 Feb 2025 14:44:16 +0530
Subject: [PATCH 03/10] rename lint

---
 ...sealed.ron => trait_sealed_became_unsealed.ron} |  4 ++--
 src/query.rs                                       |  2 +-
 .../new/Cargo.toml                                 |  2 +-
 .../new/src/lib.rs                                 |  0
 .../old/Cargo.toml                                 |  2 +-
 .../old/src/lib.rs                                 |  0
 ...aled.snap => trait_sealed_became_unsealed.snap} | 14 +++++++-------
 7 files changed, 12 insertions(+), 12 deletions(-)
 rename src/lints/{trait_sealed_becomes_unsealed.ron => trait_sealed_became_unsealed.ron} (95%)
 rename test_crates/{trait_sealed_becomes_unsealed => trait_sealed_became_unsealed}/new/Cargo.toml (66%)
 rename test_crates/{trait_sealed_becomes_unsealed => trait_sealed_became_unsealed}/new/src/lib.rs (100%)
 rename test_crates/{trait_sealed_becomes_unsealed => trait_sealed_became_unsealed}/old/Cargo.toml (66%)
 rename test_crates/{trait_sealed_becomes_unsealed => trait_sealed_became_unsealed}/old/src/lib.rs (100%)
 rename test_outputs/query_execution/{trait_sealed_becomes_unsealed.snap => trait_sealed_became_unsealed.snap} (89%)

diff --git a/src/lints/trait_sealed_becomes_unsealed.ron b/src/lints/trait_sealed_became_unsealed.ron
similarity index 95%
rename from src/lints/trait_sealed_becomes_unsealed.ron
rename to src/lints/trait_sealed_became_unsealed.ron
index 1f2db480..b72cb8f3 100644
--- a/src/lints/trait_sealed_becomes_unsealed.ron
+++ b/src/lints/trait_sealed_became_unsealed.ron
@@ -1,6 +1,6 @@
 SemverQuery(
-    id: "trait_sealed_becomes_unsealed",
-    human_readable_name: "trait sealed becomes unsealed",
+    id: "trait_sealed_became_unsealed",
+    human_readable_name: "trait sealed became unsealed",
     description: "A public sealed trait is unsealed, so users of this trait can implement it from now",
     required_update: Minor,
     lint_level: Warn,
diff --git a/src/query.rs b/src/query.rs
index b2992493..59a85a48 100644
--- a/src/query.rs
+++ b/src/query.rs
@@ -1340,7 +1340,7 @@ add_lints!(
     trait_removed_supertrait,
     trait_requires_more_const_generic_params,
     trait_requires_more_generic_type_params,
-    trait_sealed_becomes_unsealed,
+    trait_sealed_became_unsealed,
     trait_unsafe_added,
     trait_unsafe_removed,
     tuple_struct_to_plain_struct,
diff --git a/test_crates/trait_sealed_becomes_unsealed/new/Cargo.toml b/test_crates/trait_sealed_became_unsealed/new/Cargo.toml
similarity index 66%
rename from test_crates/trait_sealed_becomes_unsealed/new/Cargo.toml
rename to test_crates/trait_sealed_became_unsealed/new/Cargo.toml
index 5d8932ca..5be476bf 100644
--- a/test_crates/trait_sealed_becomes_unsealed/new/Cargo.toml
+++ b/test_crates/trait_sealed_became_unsealed/new/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 publish = false
-name = "trait_sealed_becomes_unsealed"
+name = "trait_sealed_became_unsealed"
 version = "0.1.0"
 edition = "2021"
 
diff --git a/test_crates/trait_sealed_becomes_unsealed/new/src/lib.rs b/test_crates/trait_sealed_became_unsealed/new/src/lib.rs
similarity index 100%
rename from test_crates/trait_sealed_becomes_unsealed/new/src/lib.rs
rename to test_crates/trait_sealed_became_unsealed/new/src/lib.rs
diff --git a/test_crates/trait_sealed_becomes_unsealed/old/Cargo.toml b/test_crates/trait_sealed_became_unsealed/old/Cargo.toml
similarity index 66%
rename from test_crates/trait_sealed_becomes_unsealed/old/Cargo.toml
rename to test_crates/trait_sealed_became_unsealed/old/Cargo.toml
index 5d8932ca..5be476bf 100644
--- a/test_crates/trait_sealed_becomes_unsealed/old/Cargo.toml
+++ b/test_crates/trait_sealed_became_unsealed/old/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 publish = false
-name = "trait_sealed_becomes_unsealed"
+name = "trait_sealed_became_unsealed"
 version = "0.1.0"
 edition = "2021"
 
diff --git a/test_crates/trait_sealed_becomes_unsealed/old/src/lib.rs b/test_crates/trait_sealed_became_unsealed/old/src/lib.rs
similarity index 100%
rename from test_crates/trait_sealed_becomes_unsealed/old/src/lib.rs
rename to test_crates/trait_sealed_became_unsealed/old/src/lib.rs
diff --git a/test_outputs/query_execution/trait_sealed_becomes_unsealed.snap b/test_outputs/query_execution/trait_sealed_became_unsealed.snap
similarity index 89%
rename from test_outputs/query_execution/trait_sealed_becomes_unsealed.snap
rename to test_outputs/query_execution/trait_sealed_became_unsealed.snap
index f66e15ba..5b0220b9 100644
--- a/test_outputs/query_execution/trait_sealed_becomes_unsealed.snap
+++ b/test_outputs/query_execution/trait_sealed_became_unsealed.snap
@@ -42,11 +42,11 @@ expression: "&query_execution_results"
       "visibility_limit": String("public"),
     },
   ],
-  "./test_crates/trait_sealed_becomes_unsealed/": [
+  "./test_crates/trait_sealed_became_unsealed/": [
     {
       "name": String("PublicAPIToBeUnsealed"),
       "path": List([
-        String("trait_sealed_becomes_unsealed"),
+        String("trait_sealed_became_unsealed"),
         String("PublicAPIToBeUnsealed"),
       ]),
       "span_begin_line": Uint64(2),
@@ -57,7 +57,7 @@ expression: "&query_execution_results"
     {
       "name": String("HiddenSealedInherited"),
       "path": List([
-        String("trait_sealed_becomes_unsealed"),
+        String("trait_sealed_became_unsealed"),
         String("HiddenSealedInherited"),
       ]),
       "span_begin_line": Uint64(16),
@@ -68,7 +68,7 @@ expression: "&query_execution_results"
     {
       "name": String("MethodReturnHiddenSealed"),
       "path": List([
-        String("trait_sealed_becomes_unsealed"),
+        String("trait_sealed_became_unsealed"),
         String("MethodReturnHiddenSealed"),
       ]),
       "span_begin_line": Uint64(20),
@@ -79,7 +79,7 @@ expression: "&query_execution_results"
     {
       "name": String("TransitivelyHiddenSealed"),
       "path": List([
-        String("trait_sealed_becomes_unsealed"),
+        String("trait_sealed_became_unsealed"),
         String("TransitivelyHiddenSealed"),
       ]),
       "span_begin_line": Uint64(25),
@@ -90,7 +90,7 @@ expression: "&query_execution_results"
     {
       "name": String("HiddenSealedWithWhereSelfBound"),
       "path": List([
-        String("trait_sealed_becomes_unsealed"),
+        String("trait_sealed_became_unsealed"),
         String("HiddenSealedWithWhereSelfBound"),
       ]),
       "span_begin_line": Uint64(30),
@@ -101,7 +101,7 @@ expression: "&query_execution_results"
     {
       "name": String("MethodHiddenSealed"),
       "path": List([
-        String("trait_sealed_becomes_unsealed"),
+        String("trait_sealed_became_unsealed"),
         String("MethodHiddenSealed"),
       ]),
       "span_begin_line": Uint64(38),

From d4c745df28ebbe8d3a456049875e9dfc6790239d Mon Sep 17 00:00:00 2001
From: Lovelin <100030865+lovelindhoni@users.noreply.github.com>
Date: Thu, 27 Feb 2025 18:46:47 +0530
Subject: [PATCH 04/10] feat: better descriptive example traits

---
 .../new/src/lib.rs                            | 53 ++++++++----------
 .../old/src/lib.rs                            | 56 +++++++++----------
 .../trait_sealed_became_unsealed.snap         | 50 +++++------------
 3 files changed, 62 insertions(+), 97 deletions(-)

diff --git a/test_crates/trait_sealed_became_unsealed/new/src/lib.rs b/test_crates/trait_sealed_became_unsealed/new/src/lib.rs
index 87e59a38..4a700e46 100644
--- a/test_crates/trait_sealed_became_unsealed/new/src/lib.rs
+++ b/test_crates/trait_sealed_became_unsealed/new/src/lib.rs
@@ -1,40 +1,33 @@
-// This trait is public API sealed.
-pub trait PublicAPIToBeUnsealed {
-    type Hidden;
+pub mod public_api_hidden_module_tobe_exposed {
+    pub trait Sealed {}
+    pub struct Token;
 }
 
-pub mod hidden_module {
-    /// This trait is public-API-sealed because implementing it
-    /// requires going outside the public API.
-    pub trait HiddenSealed {}
-
+mod public_api_hidden_module_to_be_unconditionally_hidden {
+    pub trait Sealed {}
     pub struct Token;
 }
 
-/// This trait is public-API-sealed since implementing it requires naming
-/// its non-public-API supertrait.
-pub trait HiddenSealedInherited: hidden_module::HiddenSealed {}
-
-/// This trait is public-API-sealed because its method's return type is doc-hidden,
-/// so external implementers would have to name a non-public-API type to write the impl.
-pub trait MethodReturnHiddenSealed {
-    fn method(&self) -> hidden_module::Token;
+// Traits transitioning from Public API Sealed → Unsealed (Lint should detect these)
+pub trait PublicAPIToBeUnsealed {
+    type Hidden;
+}
+pub trait TraitExtendsPublicAPIHiddenTrait: public_api_hidden_module_tobe_exposed::Sealed {}
+pub trait MethodReturnPublicAPIHiddenToken {
+    fn method(&self) -> public_api_hidden_module_tobe_exposed::Token;
+}
+pub trait MethodTakingPublicAPIHiddenToken {
+    fn method(&self, token: public_api_hidden_module_tobe_exposed::Token);
 }
 
-/// This trait is public-API-sealed transitively because of its supertrait.
-pub trait TransitivelyHiddenSealed: HiddenSealedInherited {}
-
-/// This trait is public-API-sealed, since `Self: hidden_module::HiddenSealed`
-/// still requires that `Self` implement a public-API-sealed trait,
-/// even though the public-API-sealed trait isn't *exactly* a supertrait.
-pub trait HiddenSealedWithWhereSelfBound
-where
-    Self: hidden_module::HiddenSealed,
+// Traits transitioning from Public API Sealed → Unconditionally Sealed (Lint should ignore these)
+pub trait TraitExtendsUnconditionallyHiddenTrait:
+    public_api_hidden_module_to_be_unconditionally_hidden::Sealed
 {
 }
-
-/// This trait is public-API-sealed because its method's argument type is doc-hidden,
-/// so external implementers would have to name a non-public-API type to write the impl.
-pub trait MethodHiddenSealed {
-    fn method(&self, token: hidden_module::Token);
+pub trait MethodReturningUnconditionallyHiddenToken {
+    fn method(&self) -> public_api_hidden_module_to_be_unconditionally_hidden::Token;
+}
+pub trait MethodTakingUnconditionallyHiddenToken {
+    fn method(&self, token: public_api_hidden_module_to_be_unconditionally_hidden::Token);
 }
diff --git a/test_crates/trait_sealed_became_unsealed/old/src/lib.rs b/test_crates/trait_sealed_became_unsealed/old/src/lib.rs
index 574e9374..2619d116 100644
--- a/test_crates/trait_sealed_became_unsealed/old/src/lib.rs
+++ b/test_crates/trait_sealed_became_unsealed/old/src/lib.rs
@@ -1,42 +1,36 @@
-// This trait is public API sealed.
-pub trait PublicAPIToBeUnsealed {
-    #[doc(hidden)]
-    type Hidden;
+#[doc(hidden)]
+pub mod public_api_hidden_module_tobe_exposed {
+    pub trait Sealed {}
+    pub struct Token;
 }
 
 #[doc(hidden)]
-pub mod hidden_module {
-    /// This trait is public-API-sealed because implementing it
-    /// requires going outside the public API.
-    pub trait HiddenSealed {}
-
+pub mod public_api_hidden_module_to_be_unconditionally_hidden {
+    pub trait Sealed {}
     pub struct Token;
 }
 
-/// This trait is public-API-sealed since implementing it requires naming
-/// its non-public-API supertrait.
-pub trait HiddenSealedInherited: hidden_module::HiddenSealed {}
-
-/// This trait is public-API-sealed because its method's return type is doc-hidden,
-/// so external implementers would have to name a non-public-API type to write the impl.
-pub trait MethodReturnHiddenSealed {
-    fn method(&self) -> hidden_module::Token;
+// Traits transitioning from Public API Sealed → Unsealed (Lint should detect these)
+pub trait PublicAPIToBeUnsealed {
+    #[doc(hidden)]
+    type Hidden;
+}
+pub trait TraitExtendsPublicAPIHiddenTrait: public_api_hidden_module_tobe_exposed::Sealed {}
+pub trait MethodReturnPublicAPIHiddenToken {
+    fn method(&self) -> public_api_hidden_module_tobe_exposed::Token;
+}
+pub trait MethodTakingPublicAPIHiddenToken {
+    fn method(&self, token: public_api_hidden_module_tobe_exposed::Token);
 }
 
-/// This trait is public-API-sealed transitively because of its supertrait.
-pub trait TransitivelyHiddenSealed: HiddenSealedInherited {}
-
-/// This trait is public-API-sealed, since `Self: hidden_module::HiddenSealed`
-/// still requires that `Self` implement a public-API-sealed trait,
-/// even though the public-API-sealed trait isn't *exactly* a supertrait.
-pub trait HiddenSealedWithWhereSelfBound
-where
-    Self: hidden_module::HiddenSealed,
+// Traits transitioning from Public API Sealed → Unconditionally Sealed (Lint should ignore these)
+pub trait TraitExtendsUnconditionallyHiddenTrait:
+    public_api_hidden_module_to_be_unconditionally_hidden::Sealed
 {
 }
-
-/// This trait is public-API-sealed because its method's argument type is doc-hidden,
-/// so external implementers would have to name a non-public-API type to write the impl.
-pub trait MethodHiddenSealed {
-    fn method(&self, token: hidden_module::Token);
+pub trait MethodReturningUnconditionallyHiddenToken {
+    fn method(&self) -> public_api_hidden_module_to_be_unconditionally_hidden::Token;
+}
+pub trait MethodTakingUnconditionallyHiddenToken {
+    fn method(&self, token: public_api_hidden_module_to_be_unconditionally_hidden::Token);
 }
diff --git a/test_outputs/query_execution/trait_sealed_became_unsealed.snap b/test_outputs/query_execution/trait_sealed_became_unsealed.snap
index 5b0220b9..b9f46893 100644
--- a/test_outputs/query_execution/trait_sealed_became_unsealed.snap
+++ b/test_outputs/query_execution/trait_sealed_became_unsealed.snap
@@ -49,63 +49,41 @@ expression: "&query_execution_results"
         String("trait_sealed_became_unsealed"),
         String("PublicAPIToBeUnsealed"),
       ]),
-      "span_begin_line": Uint64(2),
-      "span_end_line": Uint64(4),
+      "span_begin_line": Uint64(12),
+      "span_end_line": Uint64(14),
       "span_filename": String("src/lib.rs"),
       "visibility_limit": String("public"),
     },
     {
-      "name": String("HiddenSealedInherited"),
+      "name": String("TraitExtendsPublicAPIHiddenTrait"),
       "path": List([
         String("trait_sealed_became_unsealed"),
-        String("HiddenSealedInherited"),
+        String("TraitExtendsPublicAPIHiddenTrait"),
       ]),
-      "span_begin_line": Uint64(16),
-      "span_end_line": Uint64(16),
-      "span_filename": String("src/lib.rs"),
-      "visibility_limit": String("public"),
-    },
-    {
-      "name": String("MethodReturnHiddenSealed"),
-      "path": List([
-        String("trait_sealed_became_unsealed"),
-        String("MethodReturnHiddenSealed"),
-      ]),
-      "span_begin_line": Uint64(20),
-      "span_end_line": Uint64(22),
+      "span_begin_line": Uint64(15),
+      "span_end_line": Uint64(15),
       "span_filename": String("src/lib.rs"),
       "visibility_limit": String("public"),
     },
     {
-      "name": String("TransitivelyHiddenSealed"),
+      "name": String("MethodReturnPublicAPIHiddenToken"),
       "path": List([
         String("trait_sealed_became_unsealed"),
-        String("TransitivelyHiddenSealed"),
+        String("MethodReturnPublicAPIHiddenToken"),
       ]),
-      "span_begin_line": Uint64(25),
-      "span_end_line": Uint64(25),
-      "span_filename": String("src/lib.rs"),
-      "visibility_limit": String("public"),
-    },
-    {
-      "name": String("HiddenSealedWithWhereSelfBound"),
-      "path": List([
-        String("trait_sealed_became_unsealed"),
-        String("HiddenSealedWithWhereSelfBound"),
-      ]),
-      "span_begin_line": Uint64(30),
-      "span_end_line": Uint64(34),
+      "span_begin_line": Uint64(16),
+      "span_end_line": Uint64(18),
       "span_filename": String("src/lib.rs"),
       "visibility_limit": String("public"),
     },
     {
-      "name": String("MethodHiddenSealed"),
+      "name": String("MethodTakingPublicAPIHiddenToken"),
       "path": List([
         String("trait_sealed_became_unsealed"),
-        String("MethodHiddenSealed"),
+        String("MethodTakingPublicAPIHiddenToken"),
       ]),
-      "span_begin_line": Uint64(38),
-      "span_end_line": Uint64(40),
+      "span_begin_line": Uint64(19),
+      "span_end_line": Uint64(21),
       "span_filename": String("src/lib.rs"),
       "visibility_limit": String("public"),
     },

From 8e55ce5a64b29cb1ddd9ca9d8ee157a8c3fbce8e Mon Sep 17 00:00:00 2001
From: Lovelin <100030865+lovelindhoni@users.noreply.github.com>
Date: Thu, 27 Feb 2025 22:00:50 +0530
Subject: [PATCH 05/10] rename lint

---
 ... pub_api_sealed_trait_became_unsealed.ron} | 15 ++--
 src/query.rs                                  |  2 +-
 .../new/Cargo.toml                            |  2 +-
 .../new/src/lib.rs                            | 48 +++++++++++
 .../old/Cargo.toml                            |  2 +-
 .../old/src/lib.rs                            | 51 +++++++++++
 .../new/src/lib.rs                            | 33 --------
 .../old/src/lib.rs                            | 36 --------
 ...pub_api_sealed_trait_became_unsealed.snap} | 84 +++++++++----------
 9 files changed, 153 insertions(+), 120 deletions(-)
 rename src/lints/{trait_sealed_became_unsealed.ron => pub_api_sealed_trait_became_unsealed.ron} (67%)
 rename test_crates/{trait_sealed_became_unsealed => pub_api_sealed_trait_became_unsealed}/new/Cargo.toml (62%)
 create mode 100644 test_crates/pub_api_sealed_trait_became_unsealed/new/src/lib.rs
 rename test_crates/{trait_sealed_became_unsealed => pub_api_sealed_trait_became_unsealed}/old/Cargo.toml (62%)
 create mode 100644 test_crates/pub_api_sealed_trait_became_unsealed/old/src/lib.rs
 delete mode 100644 test_crates/trait_sealed_became_unsealed/new/src/lib.rs
 delete mode 100644 test_crates/trait_sealed_became_unsealed/old/src/lib.rs
 rename test_outputs/query_execution/{trait_sealed_became_unsealed.snap => pub_api_sealed_trait_became_unsealed.snap} (82%)

diff --git a/src/lints/trait_sealed_became_unsealed.ron b/src/lints/pub_api_sealed_trait_became_unsealed.ron
similarity index 67%
rename from src/lints/trait_sealed_became_unsealed.ron
rename to src/lints/pub_api_sealed_trait_became_unsealed.ron
index b72cb8f3..988ce000 100644
--- a/src/lints/trait_sealed_became_unsealed.ron
+++ b/src/lints/pub_api_sealed_trait_became_unsealed.ron
@@ -1,7 +1,9 @@
 SemverQuery(
-    id: "trait_sealed_became_unsealed",
-    human_readable_name: "trait sealed became unsealed",
-    description: "A public sealed trait is unsealed, so users of this trait can implement it from now",
+    id: "pub_api_sealed_trait_became_unsealed",
+    human_readable_name: "Sealed trait in the public API became unsealed",
+    description: "A trait in the public API that was previously sealed is now unsealed, allowing downstream crates to implement it. 
+    This could be risky: if this change needs to be reverted, it would be a breaking change, as downstream crates may already depend on their implementations of this trait. 
+    Review this change carefully to avoid unintentionally breaking compatibility in the future",
     required_update: Minor,
     lint_level: Warn,
     reference_link: Some("https://rust-lang.github.io/api-guidelines/future-proofing.html#sealed-traits-protect-against-downstream-implementations-c-sealed"),  // TODO
@@ -42,13 +44,14 @@ SemverQuery(
                 }
             }
         }
-    }
-  "#,
+    }"#,
     arguments: {
         "public": "public",
         "true": true,
     },
-    error_message: "A publicly-visible sealed trait became unsealed, so now downstream crates are able to implement it",
+    error_message: "A sealed trait in the public api has become unsealed, allowing external crates to implement it. 
+    If you later need to re-seal this trait, it will be a breaking change. 
+    Consider whether this change is intentional and whether it aligns with your stability guarantees",
     per_result_error_template: Some("trait {{join \"::\" path}} in file {{span_filename}}:{{span_begin_line}}"),
     witness: None,
 )
diff --git a/src/query.rs b/src/query.rs
index 59a85a48..396bc79e 100644
--- a/src/query.rs
+++ b/src/query.rs
@@ -1340,7 +1340,7 @@ add_lints!(
     trait_removed_supertrait,
     trait_requires_more_const_generic_params,
     trait_requires_more_generic_type_params,
-    trait_sealed_became_unsealed,
+    pub_api_sealed_trait_became_unsealed,
     trait_unsafe_added,
     trait_unsafe_removed,
     tuple_struct_to_plain_struct,
diff --git a/test_crates/trait_sealed_became_unsealed/new/Cargo.toml b/test_crates/pub_api_sealed_trait_became_unsealed/new/Cargo.toml
similarity index 62%
rename from test_crates/trait_sealed_became_unsealed/new/Cargo.toml
rename to test_crates/pub_api_sealed_trait_became_unsealed/new/Cargo.toml
index 5be476bf..8a7a0dca 100644
--- a/test_crates/trait_sealed_became_unsealed/new/Cargo.toml
+++ b/test_crates/pub_api_sealed_trait_became_unsealed/new/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 publish = false
-name = "trait_sealed_became_unsealed"
+name = "pub_api_sealed_trait_became_unsealed"
 version = "0.1.0"
 edition = "2021"
 
diff --git a/test_crates/pub_api_sealed_trait_became_unsealed/new/src/lib.rs b/test_crates/pub_api_sealed_trait_became_unsealed/new/src/lib.rs
new file mode 100644
index 00000000..c3126de2
--- /dev/null
+++ b/test_crates/pub_api_sealed_trait_became_unsealed/new/src/lib.rs
@@ -0,0 +1,48 @@
+pub mod public_api_hidden_module_to_be_exposed {
+    pub trait Sealed {}
+    pub struct Token;
+}
+
+mod public_api_hidden_module_to_be_unconditionally_hidden {
+    pub trait Sealed {}
+    pub struct Token;
+}
+
+// ─────────────────────────────────────────────────────
+// Traits transitioning from Public API Sealed → Unsealed (Lint should detect these)
+// ─────────────────────────────────────────────────────
+
+// Start: Public API Sealed → Unsealed (Lint should detect these)
+pub trait PublicAPIToBeUnsealed {
+    type Hidden;
+}
+
+pub trait TraitExtendsPublicAPIHiddenTrait: public_api_hidden_module_to_be_exposed::Sealed {}
+
+pub trait MethodReturnPublicAPIHiddenToken {
+    fn method(&self) -> public_api_hidden_module_to_be_exposed::Token;
+}
+
+pub trait MethodTakingPublicAPIHiddenToken {
+    fn method(&self, token: public_api_hidden_module_to_be_exposed::Token);
+}
+// End: Public API Sealed → Unsealed
+
+// ─────────────────────────────────────────────────────
+// Traits transitioning from Public API Sealed → Unconditionally Sealed (Lint should ignore these)
+// ─────────────────────────────────────────────────────
+
+// Start: Public API Sealed → Unconditionally Sealed (Lint should ignore these)
+pub trait TraitExtendsUnconditionallyHiddenTrait:
+    public_api_hidden_module_to_be_unconditionally_hidden::Sealed
+{
+}
+
+pub trait MethodReturningUnconditionallyHiddenToken {
+    fn method(&self) -> public_api_hidden_module_to_be_unconditionally_hidden::Token;
+}
+
+pub trait MethodTakingUnconditionallyHiddenToken {
+    fn method(&self, token: public_api_hidden_module_to_be_unconditionally_hidden::Token);
+}
+// End: Public API Sealed → Unconditionally Sealed
diff --git a/test_crates/trait_sealed_became_unsealed/old/Cargo.toml b/test_crates/pub_api_sealed_trait_became_unsealed/old/Cargo.toml
similarity index 62%
rename from test_crates/trait_sealed_became_unsealed/old/Cargo.toml
rename to test_crates/pub_api_sealed_trait_became_unsealed/old/Cargo.toml
index 5be476bf..8a7a0dca 100644
--- a/test_crates/trait_sealed_became_unsealed/old/Cargo.toml
+++ b/test_crates/pub_api_sealed_trait_became_unsealed/old/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 publish = false
-name = "trait_sealed_became_unsealed"
+name = "pub_api_sealed_trait_became_unsealed"
 version = "0.1.0"
 edition = "2021"
 
diff --git a/test_crates/pub_api_sealed_trait_became_unsealed/old/src/lib.rs b/test_crates/pub_api_sealed_trait_became_unsealed/old/src/lib.rs
new file mode 100644
index 00000000..b8129ba1
--- /dev/null
+++ b/test_crates/pub_api_sealed_trait_became_unsealed/old/src/lib.rs
@@ -0,0 +1,51 @@
+#[doc(hidden)]
+pub mod public_api_hidden_module_to_be_exposed {
+    pub trait Sealed {}
+    pub struct Token;
+}
+
+#[doc(hidden)]
+pub mod public_api_hidden_module_to_be_unconditionally_hidden {
+    pub trait Sealed {}
+    pub struct Token;
+}
+
+// ─────────────────────────────────────────────────────
+// Traits transitioning from Public API Sealed → Unsealed (Lint should detect these)
+// ─────────────────────────────────────────────────────
+
+// Start: Public API Sealed → Unsealed (Lint should detect these)
+pub trait PublicAPIToBeUnsealed {
+    #[doc(hidden)]
+    type Hidden;
+}
+
+pub trait TraitExtendsPublicAPIHiddenTrait: public_api_hidden_module_to_be_exposed::Sealed {}
+
+pub trait MethodReturnPublicAPIHiddenToken {
+    fn method(&self) -> public_api_hidden_module_to_be_exposed::Token;
+}
+
+pub trait MethodTakingPublicAPIHiddenToken {
+    fn method(&self, token: public_api_hidden_module_to_be_exposed::Token);
+}
+// End: Public API Sealed → Unsealed
+
+// ─────────────────────────────────────────────────────
+// Traits transitioning from Public API Sealed → Unconditionally Sealed (Lint should ignore these)
+// ─────────────────────────────────────────────────────
+
+// Start: Public API Sealed → Unconditionally Sealed (Lint should ignore these)
+pub trait TraitExtendsUnconditionallyHiddenTrait:
+    public_api_hidden_module_to_be_unconditionally_hidden::Sealed
+{
+}
+
+pub trait MethodReturningUnconditionallyHiddenToken {
+    fn method(&self) -> public_api_hidden_module_to_be_unconditionally_hidden::Token;
+}
+
+pub trait MethodTakingUnconditionallyHiddenToken {
+    fn method(&self, token: public_api_hidden_module_to_be_unconditionally_hidden::Token);
+}
+// End: Public API Sealed → Unconditionally Sealed
diff --git a/test_crates/trait_sealed_became_unsealed/new/src/lib.rs b/test_crates/trait_sealed_became_unsealed/new/src/lib.rs
deleted file mode 100644
index 4a700e46..00000000
--- a/test_crates/trait_sealed_became_unsealed/new/src/lib.rs
+++ /dev/null
@@ -1,33 +0,0 @@
-pub mod public_api_hidden_module_tobe_exposed {
-    pub trait Sealed {}
-    pub struct Token;
-}
-
-mod public_api_hidden_module_to_be_unconditionally_hidden {
-    pub trait Sealed {}
-    pub struct Token;
-}
-
-// Traits transitioning from Public API Sealed → Unsealed (Lint should detect these)
-pub trait PublicAPIToBeUnsealed {
-    type Hidden;
-}
-pub trait TraitExtendsPublicAPIHiddenTrait: public_api_hidden_module_tobe_exposed::Sealed {}
-pub trait MethodReturnPublicAPIHiddenToken {
-    fn method(&self) -> public_api_hidden_module_tobe_exposed::Token;
-}
-pub trait MethodTakingPublicAPIHiddenToken {
-    fn method(&self, token: public_api_hidden_module_tobe_exposed::Token);
-}
-
-// Traits transitioning from Public API Sealed → Unconditionally Sealed (Lint should ignore these)
-pub trait TraitExtendsUnconditionallyHiddenTrait:
-    public_api_hidden_module_to_be_unconditionally_hidden::Sealed
-{
-}
-pub trait MethodReturningUnconditionallyHiddenToken {
-    fn method(&self) -> public_api_hidden_module_to_be_unconditionally_hidden::Token;
-}
-pub trait MethodTakingUnconditionallyHiddenToken {
-    fn method(&self, token: public_api_hidden_module_to_be_unconditionally_hidden::Token);
-}
diff --git a/test_crates/trait_sealed_became_unsealed/old/src/lib.rs b/test_crates/trait_sealed_became_unsealed/old/src/lib.rs
deleted file mode 100644
index 2619d116..00000000
--- a/test_crates/trait_sealed_became_unsealed/old/src/lib.rs
+++ /dev/null
@@ -1,36 +0,0 @@
-#[doc(hidden)]
-pub mod public_api_hidden_module_tobe_exposed {
-    pub trait Sealed {}
-    pub struct Token;
-}
-
-#[doc(hidden)]
-pub mod public_api_hidden_module_to_be_unconditionally_hidden {
-    pub trait Sealed {}
-    pub struct Token;
-}
-
-// Traits transitioning from Public API Sealed → Unsealed (Lint should detect these)
-pub trait PublicAPIToBeUnsealed {
-    #[doc(hidden)]
-    type Hidden;
-}
-pub trait TraitExtendsPublicAPIHiddenTrait: public_api_hidden_module_tobe_exposed::Sealed {}
-pub trait MethodReturnPublicAPIHiddenToken {
-    fn method(&self) -> public_api_hidden_module_tobe_exposed::Token;
-}
-pub trait MethodTakingPublicAPIHiddenToken {
-    fn method(&self, token: public_api_hidden_module_tobe_exposed::Token);
-}
-
-// Traits transitioning from Public API Sealed → Unconditionally Sealed (Lint should ignore these)
-pub trait TraitExtendsUnconditionallyHiddenTrait:
-    public_api_hidden_module_to_be_unconditionally_hidden::Sealed
-{
-}
-pub trait MethodReturningUnconditionallyHiddenToken {
-    fn method(&self) -> public_api_hidden_module_to_be_unconditionally_hidden::Token;
-}
-pub trait MethodTakingUnconditionallyHiddenToken {
-    fn method(&self, token: public_api_hidden_module_to_be_unconditionally_hidden::Token);
-}
diff --git a/test_outputs/query_execution/trait_sealed_became_unsealed.snap b/test_outputs/query_execution/pub_api_sealed_trait_became_unsealed.snap
similarity index 82%
rename from test_outputs/query_execution/trait_sealed_became_unsealed.snap
rename to test_outputs/query_execution/pub_api_sealed_trait_became_unsealed.snap
index b9f46893..4d3e300d 100644
--- a/test_outputs/query_execution/trait_sealed_became_unsealed.snap
+++ b/test_outputs/query_execution/pub_api_sealed_trait_became_unsealed.snap
@@ -3,87 +3,87 @@ source: src/query.rs
 expression: "&query_execution_results"
 ---
 {
-  "./test_crates/trait_associated_type_marked_deprecated/": [
+  "./test_crates/pub_api_sealed_trait_became_unsealed/": [
     {
-      "name": String("PublicTraitWithHiddenType"),
+      "name": String("PublicAPIToBeUnsealed"),
       "path": List([
-        String("trait_associated_type_marked_deprecated"),
-        String("PublicTraitWithHiddenType"),
+        String("pub_api_sealed_trait_became_unsealed"),
+        String("PublicAPIToBeUnsealed"),
       ]),
-      "span_begin_line": Uint64(40),
-      "span_end_line": Uint64(44),
+      "span_begin_line": Uint64(16),
+      "span_end_line": Uint64(18),
       "span_filename": String("src/lib.rs"),
       "visibility_limit": String("public"),
     },
-  ],
-  "./test_crates/trait_method_added/": [
     {
-      "name": String("WillGainMethodWithoutDefaultAndLoseSeal"),
+      "name": String("TraitExtendsPublicAPIHiddenTrait"),
       "path": List([
-        String("trait_method_added"),
-        String("WillGainMethodWithoutDefaultAndLoseSeal"),
+        String("pub_api_sealed_trait_became_unsealed"),
+        String("TraitExtendsPublicAPIHiddenTrait"),
       ]),
-      "span_begin_line": Uint64(43),
-      "span_end_line": Uint64(45),
+      "span_begin_line": Uint64(20),
+      "span_end_line": Uint64(20),
       "span_filename": String("src/lib.rs"),
       "visibility_limit": String("public"),
     },
-  ],
-  "./test_crates/trait_method_marked_deprecated/": [
     {
-      "name": String("PublicTraitWithHiddenMethod"),
+      "name": String("MethodReturnPublicAPIHiddenToken"),
       "path": List([
-        String("trait_method_marked_deprecated"),
-        String("PublicTraitWithHiddenMethod"),
+        String("pub_api_sealed_trait_became_unsealed"),
+        String("MethodReturnPublicAPIHiddenToken"),
       ]),
-      "span_begin_line": Uint64(47),
-      "span_end_line": Uint64(51),
+      "span_begin_line": Uint64(22),
+      "span_end_line": Uint64(24),
       "span_filename": String("src/lib.rs"),
       "visibility_limit": String("public"),
     },
-  ],
-  "./test_crates/trait_sealed_became_unsealed/": [
     {
-      "name": String("PublicAPIToBeUnsealed"),
+      "name": String("MethodTakingPublicAPIHiddenToken"),
       "path": List([
-        String("trait_sealed_became_unsealed"),
-        String("PublicAPIToBeUnsealed"),
+        String("pub_api_sealed_trait_became_unsealed"),
+        String("MethodTakingPublicAPIHiddenToken"),
       ]),
-      "span_begin_line": Uint64(12),
-      "span_end_line": Uint64(14),
+      "span_begin_line": Uint64(26),
+      "span_end_line": Uint64(28),
       "span_filename": String("src/lib.rs"),
       "visibility_limit": String("public"),
     },
+  ],
+  "./test_crates/trait_associated_type_marked_deprecated/": [
     {
-      "name": String("TraitExtendsPublicAPIHiddenTrait"),
+      "name": String("PublicTraitWithHiddenType"),
       "path": List([
-        String("trait_sealed_became_unsealed"),
-        String("TraitExtendsPublicAPIHiddenTrait"),
+        String("trait_associated_type_marked_deprecated"),
+        String("PublicTraitWithHiddenType"),
       ]),
-      "span_begin_line": Uint64(15),
-      "span_end_line": Uint64(15),
+      "span_begin_line": Uint64(40),
+      "span_end_line": Uint64(44),
       "span_filename": String("src/lib.rs"),
       "visibility_limit": String("public"),
     },
+  ],
+  "./test_crates/trait_method_added/": [
     {
-      "name": String("MethodReturnPublicAPIHiddenToken"),
+      "name": String("WillGainMethodWithoutDefaultAndLoseSeal"),
       "path": List([
-        String("trait_sealed_became_unsealed"),
-        String("MethodReturnPublicAPIHiddenToken"),
+        String("trait_method_added"),
+        String("WillGainMethodWithoutDefaultAndLoseSeal"),
       ]),
-      "span_begin_line": Uint64(16),
-      "span_end_line": Uint64(18),
+      "span_begin_line": Uint64(43),
+      "span_end_line": Uint64(45),
       "span_filename": String("src/lib.rs"),
       "visibility_limit": String("public"),
     },
+  ],
+  "./test_crates/trait_method_marked_deprecated/": [
     {
-      "name": String("MethodTakingPublicAPIHiddenToken"),
+      "name": String("PublicTraitWithHiddenMethod"),
       "path": List([
-        String("trait_sealed_became_unsealed"),
-        String("MethodTakingPublicAPIHiddenToken"),
+        String("trait_method_marked_deprecated"),
+        String("PublicTraitWithHiddenMethod"),
       ]),
-      "span_begin_line": Uint64(19),
-      "span_end_line": Uint64(21),
+      "span_begin_line": Uint64(47),
+      "span_end_line": Uint64(51),
       "span_filename": String("src/lib.rs"),
       "visibility_limit": String("public"),
     },

From 0c7b5500936cab5ab01a45770ebcc4b9d1d45fe0 Mon Sep 17 00:00:00 2001
From: Lovelin <100030865+lovelindhoni@users.noreply.github.com>
Date: Thu, 27 Feb 2025 22:54:23 +0530
Subject: [PATCH 06/10] Removed TODO comment

---
 src/lints/pub_api_sealed_trait_became_unsealed.ron | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/lints/pub_api_sealed_trait_became_unsealed.ron b/src/lints/pub_api_sealed_trait_became_unsealed.ron
index 988ce000..9ad2e117 100644
--- a/src/lints/pub_api_sealed_trait_became_unsealed.ron
+++ b/src/lints/pub_api_sealed_trait_became_unsealed.ron
@@ -6,7 +6,7 @@ SemverQuery(
     Review this change carefully to avoid unintentionally breaking compatibility in the future",
     required_update: Minor,
     lint_level: Warn,
-    reference_link: Some("https://rust-lang.github.io/api-guidelines/future-proofing.html#sealed-traits-protect-against-downstream-implementations-c-sealed"),  // TODO
+    reference_link: Some("https://rust-lang.github.io/api-guidelines/future-proofing.html#sealed-traits-protect-against-downstream-implementations-c-sealed"),
     query: r#"
     {
         CrateDiff {

From 5426f017093d7095ae8b50aabbbf7aeef954a373 Mon Sep 17 00:00:00 2001
From: Lovelin <100030865+lovelindhoni@users.noreply.github.com>
Date: Fri, 28 Feb 2025 14:56:39 +0530
Subject: [PATCH 07/10] fix: lint detecting unconditionally_sealed -> unsealed
 traits

---
 .../pub_api_sealed_trait_became_unsealed.ron  |  1 +
 .../new/src/lib.rs                            | 63 ++++++++---------
 .../old/src/lib.rs                            | 69 ++++++++-----------
 .../pub_api_sealed_trait_became_unsealed.snap | 37 ++++------
 4 files changed, 72 insertions(+), 98 deletions(-)

diff --git a/src/lints/pub_api_sealed_trait_became_unsealed.ron b/src/lints/pub_api_sealed_trait_became_unsealed.ron
index 9ad2e117..cc4b8750 100644
--- a/src/lints/pub_api_sealed_trait_became_unsealed.ron
+++ b/src/lints/pub_api_sealed_trait_became_unsealed.ron
@@ -15,6 +15,7 @@ SemverQuery(
                     ... on Trait {
                         visibility_limit @filter(op: "=", value: ["$public"]) @output
                         public_api_sealed @filter(op: "=", value: ["$true"])
+                        unconditionally_sealed @filter(op: "!=", value: ["$true"])
 
                         importable_path {
                             path @output @tag
diff --git a/test_crates/pub_api_sealed_trait_became_unsealed/new/src/lib.rs b/test_crates/pub_api_sealed_trait_became_unsealed/new/src/lib.rs
index c3126de2..c3ac8d82 100644
--- a/test_crates/pub_api_sealed_trait_became_unsealed/new/src/lib.rs
+++ b/test_crates/pub_api_sealed_trait_became_unsealed/new/src/lib.rs
@@ -1,48 +1,39 @@
-pub mod public_api_hidden_module_to_be_exposed {
-    pub trait Sealed {}
-    pub struct Token;
-}
-
-mod public_api_hidden_module_to_be_unconditionally_hidden {
-    pub trait Sealed {}
-    pub struct Token;
-}
-
-// ─────────────────────────────────────────────────────
 // Traits transitioning from Public API Sealed → Unsealed (Lint should detect these)
-// ─────────────────────────────────────────────────────
+pub mod public_api_sealed_to_unsealed {
+    pub mod hidden {
+        pub trait Sealed {}
+        pub struct Token;
+    }
 
-// Start: Public API Sealed → Unsealed (Lint should detect these)
-pub trait PublicAPIToBeUnsealed {
-    type Hidden;
-}
+    pub trait PublicAPIToBeUnsealed {
+        type Hidden;
+    }
 
-pub trait TraitExtendsPublicAPIHiddenTrait: public_api_hidden_module_to_be_exposed::Sealed {}
+    pub trait TraitExtendsHiddenPublicAPITrait: hidden::Sealed {}
 
-pub trait MethodReturnPublicAPIHiddenToken {
-    fn method(&self) -> public_api_hidden_module_to_be_exposed::Token;
-}
+    pub trait MethodReturnPublicAPIHiddenToken {
+        fn method(&self) -> hidden::Token;
+    }
 
-pub trait MethodTakingPublicAPIHiddenToken {
-    fn method(&self, token: public_api_hidden_module_to_be_exposed::Token);
+    pub trait MethodTakingPublicAPIHiddenToken {
+        fn method(&self, token: hidden::Token);
+    }
 }
-// End: Public API Sealed → Unsealed
 
-// ─────────────────────────────────────────────────────
 // Traits transitioning from Public API Sealed → Unconditionally Sealed (Lint should ignore these)
-// ─────────────────────────────────────────────────────
+pub mod public_api_sealed_to_unconditionally_sealed {
+    mod hidden {
+        pub trait Sealed {}
+        pub struct Token;
+    }
 
-// Start: Public API Sealed → Unconditionally Sealed (Lint should ignore these)
-pub trait TraitExtendsUnconditionallyHiddenTrait:
-    public_api_hidden_module_to_be_unconditionally_hidden::Sealed
-{
-}
+    pub trait TraitExtendsUnconditionallyHiddenTrait: hidden::Sealed {}
 
-pub trait MethodReturningUnconditionallyHiddenToken {
-    fn method(&self) -> public_api_hidden_module_to_be_unconditionally_hidden::Token;
-}
+    pub trait MethodReturningUnconditionallyHiddenToken {
+        fn method(&self) -> hidden::Token;
+    }
 
-pub trait MethodTakingUnconditionallyHiddenToken {
-    fn method(&self, token: public_api_hidden_module_to_be_unconditionally_hidden::Token);
+    pub trait MethodTakingUnconditionallyHiddenToken {
+        fn method(&self, token: hidden::Token);
+    }
 }
-// End: Public API Sealed → Unconditionally Sealed
diff --git a/test_crates/pub_api_sealed_trait_became_unsealed/old/src/lib.rs b/test_crates/pub_api_sealed_trait_became_unsealed/old/src/lib.rs
index b8129ba1..c8506d29 100644
--- a/test_crates/pub_api_sealed_trait_became_unsealed/old/src/lib.rs
+++ b/test_crates/pub_api_sealed_trait_became_unsealed/old/src/lib.rs
@@ -1,51 +1,42 @@
-#[doc(hidden)]
-pub mod public_api_hidden_module_to_be_exposed {
-    pub trait Sealed {}
-    pub struct Token;
-}
-
-#[doc(hidden)]
-pub mod public_api_hidden_module_to_be_unconditionally_hidden {
-    pub trait Sealed {}
-    pub struct Token;
-}
-
-// ─────────────────────────────────────────────────────
 // Traits transitioning from Public API Sealed → Unsealed (Lint should detect these)
-// ─────────────────────────────────────────────────────
-
-// Start: Public API Sealed → Unsealed (Lint should detect these)
-pub trait PublicAPIToBeUnsealed {
+pub mod public_api_sealed_to_unsealed {
     #[doc(hidden)]
-    type Hidden;
-}
+    pub mod hidden {
+        pub trait Sealed {}
+        pub struct Token;
+    }
 
-pub trait TraitExtendsPublicAPIHiddenTrait: public_api_hidden_module_to_be_exposed::Sealed {}
+    pub trait PublicAPIToBeUnsealed {
+        #[doc(hidden)]
+        type Hidden;
+    }
 
-pub trait MethodReturnPublicAPIHiddenToken {
-    fn method(&self) -> public_api_hidden_module_to_be_exposed::Token;
-}
+    pub trait TraitExtendsHiddenPublicAPITrait: hidden::Sealed {}
+
+    pub trait MethodReturnPublicAPIHiddenToken {
+        fn method(&self) -> hidden::Token;
+    }
 
-pub trait MethodTakingPublicAPIHiddenToken {
-    fn method(&self, token: public_api_hidden_module_to_be_exposed::Token);
+    pub trait MethodTakingPublicAPIHiddenToken {
+        fn method(&self, token: hidden::Token);
+    }
 }
-// End: Public API Sealed → Unsealed
 
-// ─────────────────────────────────────────────────────
 // Traits transitioning from Public API Sealed → Unconditionally Sealed (Lint should ignore these)
-// ─────────────────────────────────────────────────────
+pub mod public_api_sealed_to_unconditionally_sealed {
+    #[doc(hidden)]
+    pub mod hidden {
+        pub trait Sealed {}
+        pub struct Token;
+    }
 
-// Start: Public API Sealed → Unconditionally Sealed (Lint should ignore these)
-pub trait TraitExtendsUnconditionallyHiddenTrait:
-    public_api_hidden_module_to_be_unconditionally_hidden::Sealed
-{
-}
+    pub trait TraitExtendsUnconditionallyHiddenTrait: hidden::Sealed {}
 
-pub trait MethodReturningUnconditionallyHiddenToken {
-    fn method(&self) -> public_api_hidden_module_to_be_unconditionally_hidden::Token;
-}
+    pub trait MethodReturningUnconditionallyHiddenToken {
+        fn method(&self) -> hidden::Token;
+    }
 
-pub trait MethodTakingUnconditionallyHiddenToken {
-    fn method(&self, token: public_api_hidden_module_to_be_unconditionally_hidden::Token);
+    pub trait MethodTakingUnconditionallyHiddenToken {
+        fn method(&self, token: hidden::Token);
+    }
 }
-// End: Public API Sealed → Unconditionally Sealed
diff --git a/test_outputs/query_execution/pub_api_sealed_trait_became_unsealed.snap b/test_outputs/query_execution/pub_api_sealed_trait_became_unsealed.snap
index 4d3e300d..fe591aed 100644
--- a/test_outputs/query_execution/pub_api_sealed_trait_became_unsealed.snap
+++ b/test_outputs/query_execution/pub_api_sealed_trait_became_unsealed.snap
@@ -8,21 +8,23 @@ expression: "&query_execution_results"
       "name": String("PublicAPIToBeUnsealed"),
       "path": List([
         String("pub_api_sealed_trait_became_unsealed"),
+        String("public_api_sealed_to_unsealed"),
         String("PublicAPIToBeUnsealed"),
       ]),
-      "span_begin_line": Uint64(16),
-      "span_end_line": Uint64(18),
+      "span_begin_line": Uint64(8),
+      "span_end_line": Uint64(10),
       "span_filename": String("src/lib.rs"),
       "visibility_limit": String("public"),
     },
     {
-      "name": String("TraitExtendsPublicAPIHiddenTrait"),
+      "name": String("TraitExtendsHiddenPublicAPITrait"),
       "path": List([
         String("pub_api_sealed_trait_became_unsealed"),
-        String("TraitExtendsPublicAPIHiddenTrait"),
+        String("public_api_sealed_to_unsealed"),
+        String("TraitExtendsHiddenPublicAPITrait"),
       ]),
-      "span_begin_line": Uint64(20),
-      "span_end_line": Uint64(20),
+      "span_begin_line": Uint64(12),
+      "span_end_line": Uint64(12),
       "span_filename": String("src/lib.rs"),
       "visibility_limit": String("public"),
     },
@@ -30,10 +32,11 @@ expression: "&query_execution_results"
       "name": String("MethodReturnPublicAPIHiddenToken"),
       "path": List([
         String("pub_api_sealed_trait_became_unsealed"),
+        String("public_api_sealed_to_unsealed"),
         String("MethodReturnPublicAPIHiddenToken"),
       ]),
-      "span_begin_line": Uint64(22),
-      "span_end_line": Uint64(24),
+      "span_begin_line": Uint64(14),
+      "span_end_line": Uint64(16),
       "span_filename": String("src/lib.rs"),
       "visibility_limit": String("public"),
     },
@@ -41,10 +44,11 @@ expression: "&query_execution_results"
       "name": String("MethodTakingPublicAPIHiddenToken"),
       "path": List([
         String("pub_api_sealed_trait_became_unsealed"),
+        String("public_api_sealed_to_unsealed"),
         String("MethodTakingPublicAPIHiddenToken"),
       ]),
-      "span_begin_line": Uint64(26),
-      "span_end_line": Uint64(28),
+      "span_begin_line": Uint64(18),
+      "span_end_line": Uint64(20),
       "span_filename": String("src/lib.rs"),
       "visibility_limit": String("public"),
     },
@@ -62,19 +66,6 @@ expression: "&query_execution_results"
       "visibility_limit": String("public"),
     },
   ],
-  "./test_crates/trait_method_added/": [
-    {
-      "name": String("WillGainMethodWithoutDefaultAndLoseSeal"),
-      "path": List([
-        String("trait_method_added"),
-        String("WillGainMethodWithoutDefaultAndLoseSeal"),
-      ]),
-      "span_begin_line": Uint64(43),
-      "span_end_line": Uint64(45),
-      "span_filename": String("src/lib.rs"),
-      "visibility_limit": String("public"),
-    },
-  ],
   "./test_crates/trait_method_marked_deprecated/": [
     {
       "name": String("PublicTraitWithHiddenMethod"),

From 733e7750100ba2b5c3f91d1b0fe99e4fae1492dc Mon Sep 17 00:00:00 2001
From: Lovelin <100030865+lovelindhoni@users.noreply.github.com>
Date: Sat, 1 Mar 2025 09:00:18 +0530
Subject: [PATCH 08/10] formatted error and description messages

---
 src/lints/pub_api_sealed_trait_became_unsealed.ron | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/src/lints/pub_api_sealed_trait_became_unsealed.ron b/src/lints/pub_api_sealed_trait_became_unsealed.ron
index cc4b8750..b7da8f15 100644
--- a/src/lints/pub_api_sealed_trait_became_unsealed.ron
+++ b/src/lints/pub_api_sealed_trait_became_unsealed.ron
@@ -1,9 +1,7 @@
 SemverQuery(
     id: "pub_api_sealed_trait_became_unsealed",
     human_readable_name: "Sealed trait in the public API became unsealed",
-    description: "A trait in the public API that was previously sealed is now unsealed, allowing downstream crates to implement it. 
-    This could be risky: if this change needs to be reverted, it would be a breaking change, as downstream crates may already depend on their implementations of this trait. 
-    Review this change carefully to avoid unintentionally breaking compatibility in the future",
+    description: "An public API sealed trait is now unsealed, allowing downstream crates to implement it. Reverting this in the future would be a breaking change",
     required_update: Minor,
     lint_level: Warn,
     reference_link: Some("https://rust-lang.github.io/api-guidelines/future-proofing.html#sealed-traits-protect-against-downstream-implementations-c-sealed"),
@@ -50,9 +48,7 @@ SemverQuery(
         "public": "public",
         "true": true,
     },
-    error_message: "A sealed trait in the public api has become unsealed, allowing external crates to implement it. 
-    If you later need to re-seal this trait, it will be a breaking change. 
-    Consider whether this change is intentional and whether it aligns with your stability guarantees",
+    error_message: "An public API sealed trait is now unsealed, allowing downstream crates to implement it. Resealing this later would be a breaking change.",
     per_result_error_template: Some("trait {{join \"::\" path}} in file {{span_filename}}:{{span_begin_line}}"),
     witness: None,
 )

From 5153c041fd831af000823282ecb4577c5207a931 Mon Sep 17 00:00:00 2001
From: Predrag Gruevski <2348618+obi1kenobi@users.noreply.github.com>
Date: Fri, 28 Feb 2025 23:52:07 -0500
Subject: [PATCH 09/10] Apply suggestions from code review

---
 src/lints/pub_api_sealed_trait_became_unsealed.ron | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/lints/pub_api_sealed_trait_became_unsealed.ron b/src/lints/pub_api_sealed_trait_became_unsealed.ron
index b7da8f15..33a66c8b 100644
--- a/src/lints/pub_api_sealed_trait_became_unsealed.ron
+++ b/src/lints/pub_api_sealed_trait_became_unsealed.ron
@@ -1,7 +1,7 @@
 SemverQuery(
     id: "pub_api_sealed_trait_became_unsealed",
-    human_readable_name: "Sealed trait in the public API became unsealed",
-    description: "An public API sealed trait is now unsealed, allowing downstream crates to implement it. Reverting this in the future would be a breaking change",
+    human_readable_name: "Public API sealed trait became unsealed",
+    description: "A public API sealed trait has become unsealed, allowing downstream crates to implement it. Reverting this would be a major breaking change.",
     required_update: Minor,
     lint_level: Warn,
     reference_link: Some("https://rust-lang.github.io/api-guidelines/future-proofing.html#sealed-traits-protect-against-downstream-implementations-c-sealed"),
@@ -48,7 +48,7 @@ SemverQuery(
         "public": "public",
         "true": true,
     },
-    error_message: "An public API sealed trait is now unsealed, allowing downstream crates to implement it. Resealing this later would be a breaking change.",
+    error_message: "A public API sealed trait has become unsealed, allowing downstream crates to implement it. Reverting this would be a major breaking change.",
     per_result_error_template: Some("trait {{join \"::\" path}} in file {{span_filename}}:{{span_begin_line}}"),
     witness: None,
 )

From fedbdc34d327b438749d1c2ead55175c10252650 Mon Sep 17 00:00:00 2001
From: Predrag Gruevski <2348618+obi1kenobi@users.noreply.github.com>
Date: Fri, 28 Feb 2025 23:54:09 -0500
Subject: [PATCH 10/10] Update
 src/lints/pub_api_sealed_trait_became_unsealed.ron

---
 src/lints/pub_api_sealed_trait_became_unsealed.ron | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/lints/pub_api_sealed_trait_became_unsealed.ron b/src/lints/pub_api_sealed_trait_became_unsealed.ron
index 33a66c8b..61242b3b 100644
--- a/src/lints/pub_api_sealed_trait_became_unsealed.ron
+++ b/src/lints/pub_api_sealed_trait_became_unsealed.ron
@@ -1,6 +1,6 @@
 SemverQuery(
     id: "pub_api_sealed_trait_became_unsealed",
-    human_readable_name: "Public API sealed trait became unsealed",
+    human_readable_name: "public API sealed trait became unsealed",
     description: "A public API sealed trait has become unsealed, allowing downstream crates to implement it. Reverting this would be a major breaking change.",
     required_update: Minor,
     lint_level: Warn,