Add simple tests

[Cherry-picked 2babf5c]

Author: aherlihy

compiler/src/dotty/tools/repl/ReplDriver.scala

@@ -563,11 +563,8 @@ class ReplDriver(settings: Array[String],
           val prevClassLoader = rendering.classLoader()(using state.context)
           val jarClassLoader = fromURLsParallelCapable(
             ClassPathFactory.newClassPath(jarFile)(using rootCtx).asURLs, prevClassLoader)
-//          val replOutputClassLoader = new AbstractFileClassLoader(
-//            prevOutputDir, jarClassLoader)
           rendering.myClassLoader = new AbstractFileClassLoader(
-            rootCtx.settings.outputDir.valueIn(rootCtx.settingsState), jarClassLoader) //replOutputClassLoader)
-          println(s"new classpath: ${s.context.platform.classPath(using s.context)}")
+            rootCtx.settings.outputDir.valueIn(rootCtx.settingsState), jarClassLoader)
           out.println(s"Added '$path' to classpath.")
           s
 

compiler/test-resources/repl/require-command

@@ -0,0 +1,13 @@
+scala> val z = 1
+val z: Int = 1
+
+scala>:require sbt-test/source-dependencies/canon/actual/a.jar
+Added 'sbt-test/source-dependencies/canon/actual/a.jar' to classpath.
+
+scala> import A.x
+
+scala> x
+val res0: Int = 3
+
+scala> z
+val res1: Int = 1

compiler/test-resources/repl/require-errors

@@ -0,0 +1,8 @@
+scala>:require path/does/not/exist
+Cannot add "path/does/not/exist" to classpath.
+
+scala>:require sbt-test/source-dependencies/canon/actual/a.jar
+Added 'sbt-test/source-dependencies/canon/actual/a.jar' to classpath.
+
+scala>:require sbt-test/source-dependencies/canon/actual/a.jar
+The path 'sbt-test/source-dependencies/canon/actual/a.jar' cannot be loaded, it contains a classfile that already exists on the classpath: sbt-test/source-dependencies/canon/actual/a.jar(A.class)