fix #1274: test for dotty bootstrap based on tasty

Author: liufengyun

src/dotty/tools/dotc/config/PathResolver.scala

@@ -220,13 +220,14 @@ class PathResolver(implicit ctx: Context) {
     import context._
 
     // Assemble the elements!
+    // Scala application class path takes precedence
     def basis = List[Traversable[ClassPath]](
-      classesInPath(javaBootClassPath),             // 1. The Java bootstrap class path.
-      contentsOfDirsInPath(javaExtDirs),            // 2. The Java extension class path.
-      classesInExpandedPath(javaUserClassPath),     // 3. The Java application class path.
-      classesInPath(scalaBootClassPath),            // 4. The Scala boot class path.
-      contentsOfDirsInPath(scalaExtDirs),           // 5. The Scala extension class path.
-      classesInExpandedPath(userClassPath),         // 6. The Scala application class path.
+      classesInExpandedPath(userClassPath),         // 1. The Scala application class path.
+      classesInPath(javaBootClassPath),             // 2. The Java bootstrap class path.
+      contentsOfDirsInPath(javaExtDirs),            // 3. The Java extension class path.
+      classesInExpandedPath(javaUserClassPath),     // 4. The Java application class path.
+      classesInPath(scalaBootClassPath),            // 5. The Scala boot class path.
+      contentsOfDirsInPath(scalaExtDirs),           // 6. The Scala extension class path.
       sourcesInPath(sourcePath)                     // 7. The Scala source path.
     )
 

test/dotc/tests.scala

@@ -1,10 +1,8 @@
 package dotc
 
 import test._
-import dotty.partest._
 import org.junit.Test
-import org.junit.experimental.categories._
-
+import scala.reflect.io.Directory
 import scala.io.Source
 
 // tests that match regex '(pos|dotc|run|java|compileStdLib)\.*' would be executed as benchmarks.
@@ -288,4 +286,26 @@ class tests extends CompilerTest {
   @Test def tasty_dotc_util = compileDir(dotcDir, "util", testPickling)
   @Test def tasty_tools_io = compileDir(toolsDir, "io", testPickling)
   @Test def tasty_tests = compileDir(testsDir, "tasty", testPickling)
+
+  @Test def tasty_bootstrap = {
+    // remove class files from stdlib compilation
+    Directory(defaultOutputDir + "scala").deleteRecursively()
+
+    val opt = List("-classpath", defaultOutputDir, "-Ylog-classpath")
+    // first compile dotty
+    compileDir(dottyDir, ".", List("-deep", "-Ycheck-reentrant", "-strict"))(allowDeepSubtypes)
+
+    compileDir(dottyDir, "tools", opt)
+    compileDir(toolsDir, "dotc", opt)
+    compileDir(dotcDir, "ast", opt)
+    compileDir(dotcDir, "config", opt)
+    compileDir(dotcDir, "parsing", opt)
+    compileDir(dotcDir, "printing", opt)
+    compileDir(dotcDir, "repl", opt)
+    compileDir(dotcDir, "reporting", opt)
+    compileDir(dotcDir, "rewrite", opt)
+    compileDir(dotcDir, "transform", opt)
+    compileDir(dotcDir, "typer", opt)
+    compileDir(dotcDir, "util", opt)
+  }
 }