Merge pull request #1707 from retronym/ticket/5390

SI-5390 Detect forward reference of case class apply

10 files changed, 74 insertions, 1 deletions

diff --git a/src/compiler/scala/tools/nsc/typechecker/RefChecks.scala b/src/compiler/scala/tools/nsc/typechecker/RefChecks.scala
index 3e1d3fdcc4..9bd3aa8fe5 100644
--- a/src/compiler/scala/tools/nsc/typechecker/RefChecks.scala
+++ b/src/compiler/scala/tools/nsc/typechecker/RefChecks.scala
@@ -1536,8 +1536,14 @@ abstract class RefChecks extends InfoTransform with scala.reflect.internal.trans
         sym.name == nme.apply &&
         isClassTypeAccessible(tree)
 
-      if (doTransform)
+      if (doTransform) {
+        tree foreach {
+          case i@Ident(_) =>
+            enterReference(i.pos, i.symbol) // SI-5390 need to `enterReference` for `a` in `a.B()`
+          case _ =>
+        }
         toConstructor(tree.pos, tree.tpe)
+      }
       else {
         ifNot
         tree
diff --git a/test/files/neg/t5390.check b/test/files/neg/t5390.check
new file mode 100644
index 0000000000..6a0129b898
--- /dev/null
+++ b/test/files/neg/t5390.check
@@ -0,0 +1,4 @@
+t5390.scala:7: error: forward reference extends over definition of value b
+    val b = a.B("")
+            ^
+one error found
diff --git a/test/files/neg/t5390.scala b/test/files/neg/t5390.scala
new file mode 100644
index 0000000000..dd628f8851
--- /dev/null
+++ b/test/files/neg/t5390.scala
@@ -0,0 +1,10 @@
+class A {
+  object B { def apply(s: String) = 0}
+}
+
+object X {
+  def foo {
+    val b = a.B("")
+    val a = new A
+  }
+}
\ No newline at end of file
diff --git a/test/files/neg/t5390b.check b/test/files/neg/t5390b.check
new file mode 100644
index 0000000000..cbf8fafa6b
--- /dev/null
+++ b/test/files/neg/t5390b.check
@@ -0,0 +1,4 @@
+t5390b.scala:7: error: forward reference extends over definition of value b
+    val b = a.B("")
+            ^
+one error found
diff --git a/test/files/neg/t5390b.scala b/test/files/neg/t5390b.scala
new file mode 100644
index 0000000000..c3373b87d3
--- /dev/null
+++ b/test/files/neg/t5390b.scala
@@ -0,0 +1,10 @@
+class A {
+  case class B(s: String)
+}
+
+object X {
+  def foo {
+    val b = a.B("")
+    val a = new A
+  }
+}
\ No newline at end of file
diff --git a/test/files/neg/t5390c.check b/test/files/neg/t5390c.check
new file mode 100644
index 0000000000..f8a794d690
--- /dev/null
+++ b/test/files/neg/t5390c.check
@@ -0,0 +1,4 @@
+t5390c.scala:7: error: forward reference extends over definition of value b
+    val b = new a.B("")
+                ^
+one error found
diff --git a/test/files/neg/t5390c.scala b/test/files/neg/t5390c.scala
new file mode 100644
index 0000000000..6b11576611
--- /dev/null
+++ b/test/files/neg/t5390c.scala
@@ -0,0 +1,10 @@
+class A {
+  case class B(s: String)
+}
+
+object X {
+  def foo {
+    val b = new a.B("")
+    val a = new A
+  }
+}
\ No newline at end of file
diff --git a/test/files/neg/t5390d.check b/test/files/neg/t5390d.check
new file mode 100644
index 0000000000..daa29142e7
--- /dev/null
+++ b/test/files/neg/t5390d.check
@@ -0,0 +1,4 @@
+t5390d.scala:7: error: forward reference extends over definition of value b
+    val b = a.B.toString
+            ^
+one error found
diff --git a/test/files/neg/t5390d.scala b/test/files/neg/t5390d.scala
new file mode 100644
index 0000000000..7a2671b443
--- /dev/null
+++ b/test/files/neg/t5390d.scala
@@ -0,0 +1,10 @@
+class A {
+  case class B(s: String)
+}
+
+object X {
+  def foo {
+    val b = a.B.toString
+    val a = new A
+  }
+}
\ No newline at end of file
diff --git a/test/files/pos/t5390.scala b/test/files/pos/t5390.scala
new file mode 100644
index 0000000000..36febb6a58
--- /dev/null
+++ b/test/files/pos/t5390.scala
@@ -0,0 +1,11 @@
+class A {
+  case class B[A](s: String)
+}
+
+object X {
+  def foo {
+    val a = new A
+    val b = new a.B[c.type]("") // not a forward reference
+    val c = ""
+  }
+}
\ No newline at end of file