Use re2s in the unit test for the compiler driver and fix dotty driver

Author: retronym

compilation/src/main/dotc/scala/tools/benchmark/BenchmarkDriver.scala

@@ -15,6 +15,7 @@ trait BenchmarkDriver extends BaseBenchmarkDriver {
     ctx.setSetting(ctx.settings.migration, false)
     ctx.setSetting(ctx.settings.outputDir, dotty.tools.io.AbstractFile.getDirectory(tempDir.getAbsolutePath))
     ctx.setSetting(ctx.settings.language, List("Scala2"))
+    ctx.setSetting(ctx.settings.YdropComments, true)
     val compiler = new dotty.tools.dotc.Compiler
     val reporter = dotty.tools.dotc.Bench.doCompile(compiler, allArgs)
     assert(!reporter.hasErrors)

compilation/src/test/scala/scala/tools/benchmark/BenchmarkTest.scala

@@ -6,7 +6,7 @@ import org.junit.Test
 class BenchmarkTest {
   @Test def compilesOK() = {
     val bench = new ScalacBenchmark
-    bench.source = "../corpus/vector"
+    bench.source = "../corpus/re2s"
     bench.corpusVersion = "latest"
     bench.initTemp()
     bench.compileImpl()

corpus/re2s/a311ea0/java/util/regex/Parser.scala

@@ -733,7 +733,7 @@ class Parser(wholeRegexp: String, _flags: Int) {
         case '*' | '+' | '?' =>
           repeatPos = t.pos()
           val op: Int =
-            t.pop match {
+            t.pop() match {
               case '*' => ROP.STAR
               case '+' => ROP.PLUS
               case '?' => ROP.QUEST