diff --git a/source/dub/dub.d b/source/dub/dub.d
index bcb21bb..fe5efe4 100644
--- a/source/dub/dub.d
+++ b/source/dub/dub.d
@@ -337,8 +337,12 @@
 		return ps;
 	}
 
+	// Note: This test rely on the environment, which is not how unittests should work.
+	// This should be removed / refactored to keep coverage without affecting the env.
 	unittest
 	{
+		import dub.test.base : TestDub;
+
 		scope (exit) environment.remove("DUB_REGISTRY");
 		auto dub = new TestDub(".", null, SkipPackageSuppliers.configured);
 		assert(dub.packageSuppliers.length == 0);
@@ -1458,9 +1462,13 @@
 		return compilers[0];
 	}
 
+	// This test also relies on the environment and the filesystem,
+	// as the `makePackageSuppliers` does, and should be refactored.
 	unittest
 	{
+		import dub.test.base : TestDub;
 		import std.path: buildPath, absolutePath;
+
 		auto dub = new TestDub(".", null, SkipPackageSuppliers.configured);
 		immutable olddc = environment.get("DC", null);
 		immutable oldpath = environment.get("PATH", null);
@@ -1832,30 +1840,6 @@
 	}
 }
 
-/**
- * An instance of Dub that does not rely on the environment
- *
- * This instance of dub should not read any environment variables,
- * nor should it do any file IO, to make it usable and reliable in unittests.
- * Currently it reads environment variables but does not read the configuration.
- */
-version(unittest) package class TestDub : Dub
-{
-    /// Forward to base constructor
-    public this (string root = ".", PackageSupplier[] extras = null,
-                 SkipPackageSuppliers skip = SkipPackageSuppliers.none)
-    {
-        super(root, extras, skip);
-    }
-
-	/// Avoid loading user configuration
-	protected override Settings loadConfig(ref SpecialDirs dirs) const
-	{
-		// No-op
-		return Settings.init;
-	}
-}
-
 package struct SpecialDirs {
 	/// The path where to store temporary files and directory
 	NativePath temp;
diff --git a/source/dub/test/base.d b/source/dub/test/base.d
new file mode 100644
index 0000000..6f7c7b3
--- /dev/null
+++ b/source/dub/test/base.d
@@ -0,0 +1,53 @@
+/*******************************************************************************
+
+    Base utilities (types, functions) used in tests
+
+*******************************************************************************/
+
+module dub.test.base;
+
+version (unittest):
+
+import dub.data.settings;
+public import dub.dependency;
+import dub.dub;
+import dub.package_;
+import dub.packagemanager;
+import dub.packagesuppliers.packagesupplier;
+
+// TODO: Remove and handle logging the same way we handle other IO
+import dub.internal.logging;
+
+public void enableLogging()
+{
+    setLogLevel(LogLevel.debug_);
+}
+
+public void disableLogging()
+{
+    setLogLevel(LogLevel.none);
+}
+
+/**
+ * An instance of Dub that does not rely on the environment
+ *
+ * This instance of dub should not read any environment variables,
+ * nor should it do any file IO, to make it usable and reliable in unittests.
+ * Currently it reads environment variables but does not read the configuration.
+ */
+public class TestDub : Dub
+{
+    /// Forward to base constructor
+    public this (string root = ".", PackageSupplier[] extras = null,
+                 SkipPackageSuppliers skip = SkipPackageSuppliers.none)
+    {
+        super(root, extras, skip);
+    }
+
+    /// Avoid loading user configuration
+    protected override Settings loadConfig(ref SpecialDirs dirs) const
+    {
+        // No-op
+        return Settings.init;
+    }
+}