Added bytecode tests and fixed module defn

Author: Wojtechnology

compiler/src/dotty/tools/dotc/core/Definitions.scala

@@ -575,7 +575,7 @@ class Definitions {
 
   lazy val StringContextType: TypeRef       = ctx.requiredClassRef("scala.StringContext")
   def StringContextClass(implicit ctx: Context) = StringContextType.symbol.asClass
-  def StringContextModule(implicit ctx: Context) = StringContextClass.companionClass
+  def StringContextModule(implicit ctx: Context) = StringContextClass.companionModule
 
   lazy val PartialFunctionType: TypeRef         = ctx.requiredClassRef("scala.PartialFunction")
   def PartialFunctionClass(implicit ctx: Context) = PartialFunctionType.symbol.asClass

compiler/test/dotty/tools/backend/jvm/StringInterpolatorOptTest.scala

@@ -0,0 +1,64 @@
+package dotty.tools.backend.jvm
+
+import org.junit.Assert._
+import org.junit.Test
+
+class StringInterpolatorOptTest extends DottyBytecodeTest {
+  import ASMConverters._
+
+  @Test def testRawInterpolator = {
+    val source =
+      """
+                   |class Foo {
+                   |  val one = 1
+                   |  val two = "two"
+                   |  val three = 3.0
+                   |
+                   |  def meth1: String = raw"$one plus $two$three\n"
+                   |  def meth2: String = "" + one + " plus " + two + three + "\\n"
+                   |}
+                 """.stripMargin
+
+    checkBCode(source) { dir =>
+      val clsIn   = dir.lookupName("Foo.class", directory = false).input
+      val clsNode = loadClassNode(clsIn)
+      val meth1   = getMethod(clsNode, "meth1")
+      val meth2   = getMethod(clsNode, "meth2")
+
+      val instructions1 = instructionsFromMethod(meth1)
+      val instructions2 = instructionsFromMethod(meth2)
+
+      assert(instructions1 == instructions2,
+        "the `` string interpolator incorrectly converts to string concatenation\n" +
+          diffInstructions(instructions1, instructions2))
+    }
+  }
+
+  @Test def testSInterpolator = {
+    val source =
+      """
+                   |class Foo {
+                   |  val one = 1
+                   |  val two = "two"
+                   |  val three = 3.0
+                   |
+                   |  def meth1: String = s"$one plus $two$three\n"
+                   |  def meth2: String = "" + one + " plus " + two + three + "\n"
+                   |}
+                 """.stripMargin
+
+    checkBCode(source) { dir =>
+      val clsIn   = dir.lookupName("Foo.class", directory = false).input
+      val clsNode = loadClassNode(clsIn)
+      val meth1   = getMethod(clsNode, "meth1")
+      val meth2   = getMethod(clsNode, "meth2")
+
+      val instructions1 = instructionsFromMethod(meth1)
+      val instructions2 = instructionsFromMethod(meth2)
+
+      assert(instructions1 == instructions2,
+        "the `s` string interpolator incorrectly converts to string concatenation\n" +
+          diffInstructions(instructions1, instructions2))
+    }
+  }
+}