From 5e6364459b697bdde7104bfd87a5f2f56f129722 Mon Sep 17 00:00:00 2001
From: EnzeXing <enzexing12@gmail.com>
Date: Fri, 29 Aug 2025 23:56:04 -0400
Subject: [PATCH 1/2] Fix unexpected by-name

---
 .../dotty/tools/dotc/transform/init/Objects.scala |  6 +++---
 tests/init-global/pos/multiple-by-name.scala      | 15 +++++++++++++++
 2 files changed, 18 insertions(+), 3 deletions(-)
 create mode 100644 tests/init-global/pos/multiple-by-name.scala

diff --git a/compiler/src/dotty/tools/dotc/transform/init/Objects.scala b/compiler/src/dotty/tools/dotc/transform/init/Objects.scala
index 92262d528487..61d69621b0ce 100644
--- a/compiler/src/dotty/tools/dotc/transform/init/Objects.scala
+++ b/compiler/src/dotty/tools/dotc/transform/init/Objects.scala
@@ -1364,9 +1364,9 @@ class Objects(using Context @constructorOnly):
       case UnknownValue =>
         reportWarningForUnknownValue("Calling on unknown value. " + Trace.show, Trace.position)
       case Bottom => Bottom
-      case ValueSet(values) if values.size == 1 =>
-        evalByNameParam(values.head)
-      case _: ValueSet | _: Ref | _: ArrayRef | _: Package | SafeValue(_) =>
+      case ValueSet(values) =>
+        values.map(evalByNameParam(_)).join
+      case _: Ref | _: ArrayRef | _: Package | SafeValue(_) =>
         report.warning("[Internal error] Unexpected by-name value " + value.show  + ". " + Trace.show, Trace.position)
         Bottom
     end evalByNameParam
diff --git a/tests/init-global/pos/multiple-by-name.scala b/tests/init-global/pos/multiple-by-name.scala
new file mode 100644
index 000000000000..16a6055089df
--- /dev/null
+++ b/tests/init-global/pos/multiple-by-name.scala
@@ -0,0 +1,15 @@
+class X {
+  def bar(): Int = 5
+}
+class Y extends X {
+  override def bar(): Int = 6
+}
+
+object O {
+  def foo(p: => X) = {
+    p.bar()
+  }
+
+  val a = foo(new X)
+  val b = foo(new Y)
+}
\ No newline at end of file

From de2801b6a110d2fb9ba496dd10bedda33a15b6d5 Mon Sep 17 00:00:00 2001
From: EnzeXing <enzexing12@gmail.com>
Date: Mon, 1 Sep 2025 20:10:50 -0400
Subject: [PATCH 2/2] Cache result during thunk evaluation

---
 compiler/src/dotty/tools/dotc/transform/init/Objects.scala  | 2 +-
 tests/init-global/{warn => pos}/i18628_2.scala              | 2 +-
 tests/init-global/{warn => pos}/i18628_3.scala              | 2 +-
 tests/init-global/{warn/i18628.scala => pos/i18628_4.scala} | 2 +-
 4 files changed, 4 insertions(+), 4 deletions(-)
 rename tests/init-global/{warn => pos}/i18628_2.scala (73%)
 rename tests/init-global/{warn => pos}/i18628_3.scala (72%)
 rename tests/init-global/{warn/i18628.scala => pos/i18628_4.scala} (70%)

diff --git a/compiler/src/dotty/tools/dotc/transform/init/Objects.scala b/compiler/src/dotty/tools/dotc/transform/init/Objects.scala
index 61d69621b0ce..c22fd8683949 100644
--- a/compiler/src/dotty/tools/dotc/transform/init/Objects.scala
+++ b/compiler/src/dotty/tools/dotc/transform/init/Objects.scala
@@ -1360,7 +1360,7 @@ class Objects(using Context @constructorOnly):
           case env: Env.EnvRef => Env.ofByName(sym, thisV, Env.EnvSet(Set(env)))
         }
         given Scope = byNameEnv
-        eval(code, thisV, klass)
+        eval(code, thisV, klass, cacheResult = true)
       case UnknownValue =>
         reportWarningForUnknownValue("Calling on unknown value. " + Trace.show, Trace.position)
       case Bottom => Bottom
diff --git a/tests/init-global/warn/i18628_2.scala b/tests/init-global/pos/i18628_2.scala
similarity index 73%
rename from tests/init-global/warn/i18628_2.scala
rename to tests/init-global/pos/i18628_2.scala
index 7f90f51ccc1a..272207fc1fd1 100644
--- a/tests/init-global/warn/i18628_2.scala
+++ b/tests/init-global/pos/i18628_2.scala
@@ -2,6 +2,6 @@ object Test:
   class Box(val x: Int)
 
   def recur(a: => Box, b: Box): Int =
-    a.x + recur(a, b) + b.x // warn
+    a.x + recur(a, b) + b.x
 
   recur(Box(1), Box(2))
diff --git a/tests/init-global/warn/i18628_3.scala b/tests/init-global/pos/i18628_3.scala
similarity index 72%
rename from tests/init-global/warn/i18628_3.scala
rename to tests/init-global/pos/i18628_3.scala
index 84ab1d9f6ef3..52826317cb1c 100644
--- a/tests/init-global/warn/i18628_3.scala
+++ b/tests/init-global/pos/i18628_3.scala
@@ -6,6 +6,6 @@ object Test:
   class Box(val x: Int)
 
   def recur(a: => Box, b: => Box): Int =
-    a.x + recur(a: @widen(5), b: @widen(5)) + b.x // warn // warn
+    a.x + recur(a: @widen(5), b: @widen(5)) + b.x
 
   recur(Box(1), Box(2))
\ No newline at end of file
diff --git a/tests/init-global/warn/i18628.scala b/tests/init-global/pos/i18628_4.scala
similarity index 70%
rename from tests/init-global/warn/i18628.scala
rename to tests/init-global/pos/i18628_4.scala
index afd5c14d0b7d..8ea91a381276 100644
--- a/tests/init-global/warn/i18628.scala
+++ b/tests/init-global/pos/i18628_4.scala
@@ -2,6 +2,6 @@ object Test:
   class Box(val x: Int)
 
   def recur(a: => Box, b: => Box): Int =
-    a.x + recur(a, b) + b.x // warn // warn
+    a.x + recur(a, b) + b.x
 
   recur(Box(1), Box(2))
\ No newline at end of file