SI-8173 add support for patterns like init :+ last to quasiquotes

Adds support for patterns like:

  val q"{ ..$init; $last }" = q"{ a; b; c }"
  // init == List(q"a", q"b")
  // last == q"c"

Which under the hood get compiled as `:+` patterns:

  SyntacticBlock(init :+ last)

1 files changed, 26 insertions, 6 deletions

diff --git a/test/files/scalacheck/quasiquotes/TypeDeconstructionProps.scala b/test/files/scalacheck/quasiquotes/TypeDeconstructionProps.scala
index 499f5d6d8e..44f110a3d5 100644
--- a/test/files/scalacheck/quasiquotes/TypeDeconstructionProps.scala
+++ b/test/files/scalacheck/quasiquotes/TypeDeconstructionProps.scala
@@ -13,23 +13,43 @@ object TypeDeconstructionProps extends QuasiquoteProperties("type deconstruction
     a ≈ Ident(name1) && b ≈ Ident(name2)
   }
 
-  property("tuple type") = test {
+  property("tuple type (1)") = test {
     val tq"(..$empty)" = tq"_root_.scala.Unit"
     assert(empty.isEmpty)
+  }
+
+  property("tuple type (2)") = test {
     val tq"(..$ts)" = tq"(t1, t2)"
     assert(ts ≈ List(tq"t1", tq"t2"))
+  }
+
+  property("tuple type (3)") = test {
     val tq"($head, ..$tail)" = tq"(t0, t1, t2)"
-    assert(head ≈ tq"t0" && tail ≈ List(tq"t1", tq"t2"))
+    assert(head ≈ tq"t0")
+    assert(tail ≈ List(tq"t1", tq"t2"))
+  }
+
+  property("tuple type (4)") = test {
+    val tq"(..$init, $last)" = tq"(t0, t1, t2)"
+    assert(init ≈ List(tq"t0", tq"t1"))
+    assert(last ≈ tq"t2")
   }
 
   property("refined type") = test {
     val tq"T { ..$stats }" = tq"T { def foo; val x: Int; type Y = String }"
-    assert(stats ≈ (q"def foo" :: q"val x: Int" :: q"type Y = String" :: Nil))
+    assert(stats ≈ List(q"def foo", q"val x: Int", q"type Y = String"))
   }
 
-  property("function type") = test {
+  property("function type (1)") = test {
     val tq"..$argtpes => $restpe" = tq"(A, B) => C"
-    assert(argtpes ≈ (tq"A" :: tq"B" :: Nil))
+    assert(argtpes ≈ List(tq"A", tq"B"))
     assert(restpe ≈ tq"C")
   }
-}
\ No newline at end of file
+
+  property("function type (2)") = test {
+    val tq"(..$argtpes, $arglast) => $restpe" = tq"(A, B, C) => D"
+    assert(argtpes ≈ List(tq"A", tq"B"))
+    assert(arglast ≈ tq"C")
+    assert(restpe ≈ tq"D")
+  }
+}