Keep existing files in index when updating a package with --force (#70)

s3pypi/package.py

@@ -136,9 +136,13 @@ def to_html(self):
         return self.template.render({"packages": self.packages})
 
     def add_package(self, package, force=False):
-        if force:
-            self.packages.discard(package)
-        elif any(p.version == package.version for p in self.packages):
+        existing = next(
+            (p for p in self.packages if p.version == package.version), None
+        )
+        if existing and force:
+            self.packages.discard(existing)
+            package = Package(str(package), existing.files | package.files)
+        elif existing:
             raise S3PyPiError(
                 "%s already exists! You should use a different version (use --force to override)."
                 % package

tests/unit/test_package.py

@@ -48,7 +48,9 @@ def test_add_package_force():
 
     index = Index([pkg1])
     index.add_package(pkg2, force=True)
-    assert index.packages == {pkg2}
+
+    assert len(index.packages) == 1
+    assert next(iter(index.packages)).files == {"foo", "bar"}
 
 
 def test_directory_normalize_package_name():