From 95966d8fd0c37c86fbe6f77ed85f6372928bf4a5 Mon Sep 17 00:00:00 2001
From: Hamza Remmal <hamza@remmal.net>
Date: Thu, 11 Sep 2025 11:38:37 +0200
Subject: [PATCH] fix: do not transform `Ident` to `This` in PostTyper anymore

[Cherry-picked d03af581af220a937a4bcee0e317ce346326403c]
---
 .../src/dotty/tools/dotc/transform/PostTyper.scala    |  6 +-----
 tests/run/i23875.check                                |  3 +++
 tests/run/i23875.scala                                | 11 +++++++++++
 3 files changed, 15 insertions(+), 5 deletions(-)
 create mode 100644 tests/run/i23875.check
 create mode 100644 tests/run/i23875.scala

diff --git a/compiler/src/dotty/tools/dotc/transform/PostTyper.scala b/compiler/src/dotty/tools/dotc/transform/PostTyper.scala
index 9f79c063dc03..d1246aacf7d5 100644
--- a/compiler/src/dotty/tools/dotc/transform/PostTyper.scala
+++ b/compiler/src/dotty/tools/dotc/transform/PostTyper.scala
@@ -391,11 +391,7 @@ class PostTyper extends MacroTransform with InfoTransformer { thisPhase =>
             checkNotPackage(tree)
           else
             registerNeedsInlining(tree)
-            val tree1 = checkUsableAsValue(tree)
-            tree1.tpe match {
-              case tpe: ThisType => This(tpe.cls).withSpan(tree.span)
-              case _ => tree1
-            }
+            checkUsableAsValue(tree)
         case tree @ Select(qual, name) =>
           registerNeedsInlining(tree)
           if name.isTypeName then
diff --git a/tests/run/i23875.check b/tests/run/i23875.check
new file mode 100644
index 000000000000..36bc6136b8bf
--- /dev/null
+++ b/tests/run/i23875.check
@@ -0,0 +1,3 @@
+true
+false
+false
diff --git a/tests/run/i23875.scala b/tests/run/i23875.scala
new file mode 100644
index 000000000000..6993fb39f50b
--- /dev/null
+++ b/tests/run/i23875.scala
@@ -0,0 +1,11 @@
+object Foo {
+  override def equals(that : Any) = that match {
+    case _: this.type => true
+    case _            => false
+  }
+}
+
+@main def Test =
+  println(Foo.equals(Foo))
+  println(Foo.equals(new AnyRef {}))
+  println(Foo.equals(0))