From a0d1bb3e303f023e477979b7851582078b9493b8 Mon Sep 17 00:00:00 2001
From: Predrag Gruevski <obi1kenobi82@gmail.com>
Date: Tue, 31 Jan 2023 01:32:09 +0000
Subject: [PATCH] Test case: replace type with a more generic one without major
 change.

---
 .../new/Cargo.toml                            |  7 ++
 .../new/src/lib.rs                            | 78 +++++++++++++++++++
 .../old/Cargo.toml                            |  7 ++
 .../old/src/lib.rs                            | 46 +++++++++++
 4 files changed, 138 insertions(+)
 create mode 100644 test_crates/type_alias_over_more_generic_underlying/new/Cargo.toml
 create mode 100644 test_crates/type_alias_over_more_generic_underlying/new/src/lib.rs
 create mode 100644 test_crates/type_alias_over_more_generic_underlying/old/Cargo.toml
 create mode 100644 test_crates/type_alias_over_more_generic_underlying/old/src/lib.rs

diff --git a/test_crates/type_alias_over_more_generic_underlying/new/Cargo.toml b/test_crates/type_alias_over_more_generic_underlying/new/Cargo.toml
new file mode 100644
index 00000000..46ab5ffa
--- /dev/null
+++ b/test_crates/type_alias_over_more_generic_underlying/new/Cargo.toml
@@ -0,0 +1,7 @@
+[package]
+publish = false
+name = "type_alias_over_more_generic_underlying"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
diff --git a/test_crates/type_alias_over_more_generic_underlying/new/src/lib.rs b/test_crates/type_alias_over_more_generic_underlying/new/src/lib.rs
new file mode 100644
index 00000000..5ab8cd01
--- /dev/null
+++ b/test_crates/type_alias_over_more_generic_underlying/new/src/lib.rs
@@ -0,0 +1,78 @@
+//! We're going to replace the original type (named like `OriginalType`) with two types:
+//! - `pub struct NewType<A, B = ()>`
+//! - `pub type OriginalType<A> = NewType<A>`
+//!
+//! This is not semver-major, since the type alias has:
+//! - the same name
+//! - the same fields/variants
+//! - the same constructibility and pattern-matching behavior.
+
+pub struct NewStructOnlyPrivateFields<A> {
+    _marker: std::marker::PhantomData<A>,
+}
+
+pub type OriginalStructOnlyPrivateFields = NewStructOnlyPrivateFields<()>;
+
+// ---
+
+pub struct NewStructGeneric<A, B = ()> {
+    _marker: std::marker::PhantomData<(A, B)>,
+}
+
+pub type OriginalStructGeneric<A> = NewStructGeneric<A>;
+
+// ---
+
+pub struct NewStructMixOfFields<A> {
+    _marker: std::marker::PhantomData<A>,
+    pub x: i64,
+}
+
+pub type OriginalStructMixOfFields = NewStructMixOfFields<()>;
+
+// ---
+
+pub struct NewStructConstructible<T> {
+    pub x: T,
+}
+
+pub type OriginalStructConstructible = NewStructConstructible<i64>;
+
+// ---
+
+pub struct NewStructEmpty<A> {
+    _marker: std::marker::PhantomData<A>,
+}
+
+pub type OriginalStructEmpty = NewStructEmpty<()>;
+
+// ---
+
+#[non_exhaustive]
+pub struct NewStructConstructibleNonexhaustive<A> {
+    pub x: A,
+}
+
+pub type OriginalStructConstructibleNonexhaustive = NewStructConstructibleNonexhaustive<i64>;
+
+// ---
+
+#[non_exhaustive]
+pub struct NewStructEmptyNonexhaustive<A> {
+    pub x: A,
+}
+
+pub type OriginalStructEmptyNonexhaustive = NewStructEmptyNonexhaustive<i64>;
+
+// ---
+// The enum case is interesting: to add a generic parameter, we need to use it somewhere.
+// We'll need to add a variant, so the original enum must have been non-exhaustive
+// to avoid an immediate major breaking change.
+
+#[non_exhaustive]
+pub enum NewEnumNonexhaustive<A> {
+    First,
+    Second(A),
+}
+
+pub type OriginalEnumNonexhaustive = NewEnumNonexhaustive<()>;
diff --git a/test_crates/type_alias_over_more_generic_underlying/old/Cargo.toml b/test_crates/type_alias_over_more_generic_underlying/old/Cargo.toml
new file mode 100644
index 00000000..46ab5ffa
--- /dev/null
+++ b/test_crates/type_alias_over_more_generic_underlying/old/Cargo.toml
@@ -0,0 +1,7 @@
+[package]
+publish = false
+name = "type_alias_over_more_generic_underlying"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
diff --git a/test_crates/type_alias_over_more_generic_underlying/old/src/lib.rs b/test_crates/type_alias_over_more_generic_underlying/old/src/lib.rs
new file mode 100644
index 00000000..f141436b
--- /dev/null
+++ b/test_crates/type_alias_over_more_generic_underlying/old/src/lib.rs
@@ -0,0 +1,46 @@
+//! We're going to replace the original type (named like `OriginalType`) with two types:
+//! - `pub struct NewType<A, B = ()>`
+//! - `pub type OriginalType<A> = NewType<A>`
+//!
+//! This is not semver-major, since the type alias has:
+//! - the same name
+//! - the same fields
+//! - the same constructibility and pattern-matching behavior.
+
+pub struct OriginalStructOnlyPrivateFields {
+    _marker: std::marker::PhantomData<()>,
+}
+
+pub struct OriginalStructGeneric<A> {
+    _marker: std::marker::PhantomData<A>,
+}
+
+pub struct OriginalStructMixOfFields {
+    _marker: std::marker::PhantomData<()>,
+    pub x: i64,
+}
+
+pub struct OriginalStructConstructible {
+    pub x: i64,
+}
+
+pub struct OriginalStructEmpty {}
+
+#[non_exhaustive]
+pub struct OriginalStructConstructibleNonexhaustive {
+    pub x: i64,
+}
+
+#[non_exhaustive]
+pub struct OriginalStructEmptyNonexhaustive {
+    pub x: i64,
+}
+
+// The enum case is interesting: to add a generic parameter, we need to use it somewhere.
+// We'll need to add a variant, so the original enum must have been non-exhaustive
+// to avoid an immediate major breaking change.
+
+#[non_exhaustive]
+pub enum OriginalEnumNonexhaustive {
+    First,
+}