Replace CompilationTest + by aggregateTests

The motivation is to avoid bugs like the one fixed in scala#6423 to ever happen.
In the previous scheme a missing `+` results in tests not being executed,
while now a missing comma will be a compilation error.

Author: nicolasstucki

compiler/test/dotty/tools/dotc/BootstrappedOnlyCompilationTests.scala

@@ -17,6 +17,7 @@ class BootstrappedOnlyCompilationTests extends ParallelTesting {
   import ParallelTesting._
   import TestConfiguration._
   import BootstrappedOnlyCompilationTests._
+  import CompilationTest.aggregateTests
 
   // Test suite configuration --------------------------------------------------
 
@@ -31,58 +32,62 @@ class BootstrappedOnlyCompilationTests extends ParallelTesting {
 
   @Test def posMacros: Unit = {
     implicit val testGroup: TestGroup = TestGroup("compilePosMacros")
-    compileFilesInDir("tests/pos-macros", defaultOptions)
-  }.checkCompile()
+    compileFilesInDir("tests/pos-macros", defaultOptions).checkCompile()
+  }
 
   @Test def posWithCompiler: Unit = {
     implicit val testGroup: TestGroup = TestGroup("compilePosWithCompiler")
-    compileFilesInDir("tests/pos-with-compiler", withCompilerOptions) +
-    compileDir("compiler/src/dotty/tools/dotc/ast", withCompilerOptions) +
-    compileDir("compiler/src/dotty/tools/dotc/config", withCompilerOptions) +
-    compileDir("compiler/src/dotty/tools/dotc/core", withCompilerOptions) +
-    compileDir("compiler/src/dotty/tools/dotc/transform", withCompilerOptions) +
-    compileDir("compiler/src/dotty/tools/dotc/parsing", withCompilerOptions) +
-    compileDir("compiler/src/dotty/tools/dotc/printing", withCompilerOptions) +
-    compileDir("compiler/src/dotty/tools/dotc/reporting", withCompilerOptions) +
-    compileDir("compiler/src/dotty/tools/dotc/typer", withCompilerOptions) +
-    compileDir("compiler/src/dotty/tools/dotc/util", withCompilerOptions) +
-    compileDir("compiler/src/dotty/tools/io", withCompilerOptions)
-  }.checkCompile()
+    aggregateTests(
+      compileFilesInDir("tests/pos-with-compiler", withCompilerOptions),
+      compileDir("compiler/src/dotty/tools/dotc/ast", withCompilerOptions),
+      compileDir("compiler/src/dotty/tools/dotc/config", withCompilerOptions),
+      compileDir("compiler/src/dotty/tools/dotc/core", withCompilerOptions),
+      compileDir("compiler/src/dotty/tools/dotc/transform", withCompilerOptions),
+      compileDir("compiler/src/dotty/tools/dotc/parsing", withCompilerOptions),
+      compileDir("compiler/src/dotty/tools/dotc/printing", withCompilerOptions),
+      compileDir("compiler/src/dotty/tools/dotc/reporting", withCompilerOptions),
+      compileDir("compiler/src/dotty/tools/dotc/typer", withCompilerOptions),
+      compileDir("compiler/src/dotty/tools/dotc/util", withCompilerOptions),
+      compileDir("compiler/src/dotty/tools/io", withCompilerOptions)
+    ).checkCompile()
+  }
 
   @Test def posTwiceWithCompiler: Unit = {
     implicit val testGroup: TestGroup = TestGroup("posTwiceWithCompiler")
-    compileFile("tests/pos-with-compiler/Labels.scala", withCompilerOptions) +
-    compileFile("tests/pos-with-compiler/Patterns.scala", withCompilerOptions) +
-    compileList(
-      "testNonCyclic",
-      List(
-        "compiler/src/dotty/tools/dotc/CompilationUnit.scala",
-        "compiler/src/dotty/tools/dotc/core/Types.scala",
-        "compiler/src/dotty/tools/dotc/ast/Trees.scala"
-      ),
-      withCompilerOptions
-    ) +
-    compileList(
-      "testIssue34",
-      List(
-        "compiler/src/dotty/tools/dotc/config/Properties.scala",
-        "compiler/src/dotty/tools/dotc/config/PathResolver.scala"
+    aggregateTests(
+      compileFile("tests/pos-with-compiler/Labels.scala", withCompilerOptions),
+      compileFile("tests/pos-with-compiler/Patterns.scala", withCompilerOptions),
+      compileList(
+        "testNonCyclic",
+        List(
+          "compiler/src/dotty/tools/dotc/CompilationUnit.scala",
+          "compiler/src/dotty/tools/dotc/core/Types.scala",
+          "compiler/src/dotty/tools/dotc/ast/Trees.scala"
+        ),
+        withCompilerOptions
       ),
-      withCompilerOptions
-    )
-  }.times(2).checkCompile()
+      compileList(
+        "testIssue34",
+        List(
+          "compiler/src/dotty/tools/dotc/config/Properties.scala",
+          "compiler/src/dotty/tools/dotc/config/PathResolver.scala"
+        ),
+        withCompilerOptions
+      )
+    ).times(2).checkCompile()
+  }
 
   // Negative tests ------------------------------------------------------------
 
   @Test def negMacros: Unit = {
     implicit val testGroup: TestGroup = TestGroup("compileNegWithCompiler")
-    compileFilesInDir("tests/neg-macros", defaultOptions)
-  }.checkExpectedErrors()
+    compileFilesInDir("tests/neg-macros", defaultOptions).checkExpectedErrors()
+  }
 
   @Test def negWithCompiler: Unit = {
     implicit val testGroup: TestGroup = TestGroup("compileNegWithCompiler")
-    compileFilesInDir("tests/neg-with-compiler", withCompilerOptions)
-  }.checkExpectedErrors()
+    compileFilesInDir("tests/neg-with-compiler", withCompilerOptions).checkExpectedErrors()
+  }
 
   // Run tests -----------------------------------------------------------------
 
@@ -93,10 +98,12 @@ class BootstrappedOnlyCompilationTests extends ParallelTesting {
 
   @Test def runWithCompiler: Unit = {
     implicit val testGroup: TestGroup = TestGroup("runWithCompiler")
-    compileFilesInDir("tests/run-with-compiler", withCompilerOptions) +
-    compileDir("tests/run-with-compiler-custom-args/tasty-interpreter", withCompilerOptions) +
-    compileFile("tests/run-with-compiler-custom-args/staged-streams_1.scala", withCompilerOptions without "-Yno-deep-subtypes")
-  }.checkRuns()
+    aggregateTests(
+      compileFilesInDir("tests/run-with-compiler", withCompilerOptions),
+      compileDir("tests/run-with-compiler-custom-args/tasty-interpreter", withCompilerOptions),
+      compileFile("tests/run-with-compiler-custom-args/staged-streams_1.scala", withCompilerOptions without "-Yno-deep-subtypes")
+    ).checkRuns()
+  }
 
   // Pickling Tests ------------------------------------------------------------
   //
@@ -106,26 +113,28 @@ class BootstrappedOnlyCompilationTests extends ParallelTesting {
   @Test def picklingWithCompiler: Unit = {
     val jvmBackendFilter = FileFilter.exclude(List("BTypes.scala", "Primitives.scala")) // TODO
     implicit val testGroup: TestGroup = TestGroup("testPicklingWithCompiler")
-    compileDir("compiler/src/dotty/tools", picklingWithCompilerOptions, recursive = false) +
-    compileDir("compiler/src/dotty/tools/dotc", picklingWithCompilerOptions, recursive = false) +
-    compileDir("library/src/dotty/runtime", picklingWithCompilerOptions) +
-    compileFilesInDir("compiler/src/dotty/tools/backend/jvm", picklingWithCompilerOptions, jvmBackendFilter) +
-    compileDir("compiler/src/dotty/tools/dotc/ast", picklingWithCompilerOptions) +
-    compileDir("compiler/src/dotty/tools/dotc/core", picklingWithCompilerOptions, recursive = false) +
-    compileDir("compiler/src/dotty/tools/dotc/config", picklingWithCompilerOptions) +
-    compileDir("compiler/src/dotty/tools/dotc/parsing", picklingWithCompilerOptions) +
-    compileDir("compiler/src/dotty/tools/dotc/printing", picklingWithCompilerOptions) +
-    compileDir("compiler/src/dotty/tools/repl", picklingWithCompilerOptions) +
-    compileDir("compiler/src/dotty/tools/dotc/rewrites", picklingWithCompilerOptions) +
-    compileDir("compiler/src/dotty/tools/dotc/transform", picklingWithCompilerOptions) +
-    compileDir("compiler/src/dotty/tools/dotc/typer", picklingWithCompilerOptions) +
-    compileDir("compiler/src/dotty/tools/dotc/util", picklingWithCompilerOptions) +
-    compileDir("compiler/src/dotty/tools/io", picklingWithCompilerOptions) +
-    compileFile("tests/pos/pickleinf.scala", picklingWithCompilerOptions) +
-    compileDir("compiler/src/dotty/tools/dotc/core/classfile", picklingWithCompilerOptions) +
-    compileDir("compiler/src/dotty/tools/dotc/core/tasty", picklingWithCompilerOptions) +
-    compileDir("compiler/src/dotty/tools/dotc/core/unpickleScala2", picklingWithCompilerOptions)
-  }.limitThreads(4).checkCompile()
+    aggregateTests(
+      compileDir("compiler/src/dotty/tools", picklingWithCompilerOptions, recursive = false),
+      compileDir("compiler/src/dotty/tools/dotc", picklingWithCompilerOptions, recursive = false),
+      compileDir("library/src/dotty/runtime", picklingWithCompilerOptions),
+      compileFilesInDir("compiler/src/dotty/tools/backend/jvm", picklingWithCompilerOptions, jvmBackendFilter),
+      compileDir("compiler/src/dotty/tools/dotc/ast", picklingWithCompilerOptions),
+      compileDir("compiler/src/dotty/tools/dotc/core", picklingWithCompilerOptions, recursive = false),
+      compileDir("compiler/src/dotty/tools/dotc/config", picklingWithCompilerOptions),
+      compileDir("compiler/src/dotty/tools/dotc/parsing", picklingWithCompilerOptions),
+      compileDir("compiler/src/dotty/tools/dotc/printing", picklingWithCompilerOptions),
+      compileDir("compiler/src/dotty/tools/repl", picklingWithCompilerOptions),
+      compileDir("compiler/src/dotty/tools/dotc/rewrites", picklingWithCompilerOptions),
+      compileDir("compiler/src/dotty/tools/dotc/transform", picklingWithCompilerOptions),
+      compileDir("compiler/src/dotty/tools/dotc/typer", picklingWithCompilerOptions),
+      compileDir("compiler/src/dotty/tools/dotc/util", picklingWithCompilerOptions),
+      compileDir("compiler/src/dotty/tools/io", picklingWithCompilerOptions),
+      compileFile("tests/pos/pickleinf.scala", picklingWithCompilerOptions),
+      compileDir("compiler/src/dotty/tools/dotc/core/classfile", picklingWithCompilerOptions),
+      compileDir("compiler/src/dotty/tools/dotc/core/tasty", picklingWithCompilerOptions),
+      compileDir("compiler/src/dotty/tools/dotc/core/unpickleScala2", picklingWithCompilerOptions)
+    ).limitThreads(4).checkCompile()
+  }
 
   @Test def testPlugins: Unit = {
     val pluginFile = "plugin.properties"