diff --git a/source/dub/dub.d b/source/dub/dub.d
index a36ac53..871df0f 100644
--- a/source/dub/dub.d
+++ b/source/dub/dub.d
@@ -368,15 +368,15 @@
 		import dub.test.base : TestDub;
 
 		scope (exit) environment.remove("DUB_REGISTRY");
-		auto dub = new TestDub(".", null, SkipPackageSuppliers.configured);
+		auto dub = new TestDub(null, ".", null, SkipPackageSuppliers.configured);
 		assert(dub.packageSuppliers.length == 0);
 		environment["DUB_REGISTRY"] = "http://example.com/";
-		dub = new TestDub(".", null, SkipPackageSuppliers.configured);
+		dub = new TestDub(null, ".", null, SkipPackageSuppliers.configured);
 		assert(dub.packageSuppliers.length == 1);
 		environment["DUB_REGISTRY"] = "http://example.com/;http://foo.com/";
-		dub = new TestDub(".", null, SkipPackageSuppliers.configured);
+		dub = new TestDub(null, ".", null, SkipPackageSuppliers.configured);
 		assert(dub.packageSuppliers.length == 2);
-		dub = new TestDub(".", [new RegistryPackageSupplier(URL("http://bar.com/"))], SkipPackageSuppliers.configured);
+		dub = new TestDub(null, ".", [new RegistryPackageSupplier(URL("http://bar.com/"))], SkipPackageSuppliers.configured);
 		assert(dub.packageSuppliers.length == 3);
 
 		dub = new TestDub();
@@ -1648,7 +1648,7 @@
 		import dub.test.base : TestDub;
 		import std.path: buildPath, absolutePath;
 
-		auto dub = new TestDub(".", null, SkipPackageSuppliers.configured);
+		auto dub = new TestDub(null, ".", null, SkipPackageSuppliers.configured);
 		immutable olddc = environment.get("DC", null);
 		immutable oldpath = environment.get("PATH", null);
 		immutable testdir = "test-determineDefaultCompiler";
diff --git a/source/dub/test/base.d b/source/dub/test/base.d
index 5d6a81a..44b241f 100644
--- a/source/dub/test/base.d
+++ b/source/dub/test/base.d
@@ -181,15 +181,6 @@
         cache: Root ~ "user/" ~ "cache/",
     };
 
-    /// Forward to base constructor
-    public this (string root = ProjectPath.toNativeString(),
-        PackageSupplier[] extras = null,
-        SkipPackageSuppliers skip = SkipPackageSuppliers.none)
-    {
-        this.fs = new FSEntry();
-        super(root, extras, skip);
-    }
-
     /***************************************************************************
 
         Instantiate a new `TestDub` instance with the provided filesystem state
@@ -200,14 +191,20 @@
         Params:
           dg = Delegate to be called with the filesystem, before `TestDub`
                instantiation is performed;
+          root = The root path for this instance (forwarded to Dub)
+          extras = Extras `PackageSupplier`s (forwarded to Dub)
+          skip = What `PackageSupplier`s to skip (forwarded to Dub)
 
     ***************************************************************************/
 
-    public this (scope void delegate(scope FSEntry root) dg)
+    public this (scope void delegate(scope FSEntry root) dg = null,
+        string root = ProjectPath.toNativeString(),
+        PackageSupplier[] extras = null,
+        SkipPackageSuppliers skip = SkipPackageSuppliers.none)
     {
         this.fs = new FSEntry();
-        dg(this.fs);
-        super(ProjectPath.toNativeString(), null, SkipPackageSuppliers.none);
+        if (dg !is null) dg(this.fs);
+        super(root, extras, skip);
     }
 
     /// Avoid loading user configuration