Do not fail with null sizes and counts

Signed-off-by: Philippe Ombredanne <pombredanne@nexb.com>

Author: pombredanne

src/commoncode/resource.py

@@ -884,7 +884,7 @@ def compute_counts(self, skip_root=False, skip_filtered=False):
             files_count += 1
         else:
             dirs_count += 1
-        size_count += root.size
+        size_count += root.size or 0
 
         return files_count, dirs_count, size_count
 
@@ -1133,9 +1133,9 @@ def _compute_children_counts(self, codebase, skip_filtered=False):
         """
         files_count = dirs_count = size_count = 0
         for child in self.children(codebase):
-            files_count += child.files_count
-            dirs_count += child.dirs_count
-            size_count += child.size_count
+            files_count += child.files_count or 0
+            dirs_count += child.dirs_count or 0
+            size_count += child.size_count or 0
 
             if skip_filtered and child.is_filtered:
                 continue
@@ -1144,7 +1144,7 @@ def _compute_children_counts(self, codebase, skip_filtered=False):
                 files_count += 1
             else:
                 dirs_count += 1
-            size_count += child.size
+            size_count += child.size or 0
 
         self.files_count = files_count
         self.dirs_count = dirs_count

tests/data/resource/virtual_codebase/node-16-slim.json

@@ -0,0 +1,26 @@
+{
+"headers": [],
+"files": [
+{
+  "for_packages": [
+    "pkg:deb/debian/bash@5.0-4?arch=amd64"
+  ],
+  "compliance_alert": "",
+  "path": "/node_16_slim.tar-extract/02c055ef67f5904019f43a41ea5f099996d8e7633749b6e606c400526b2c4b33/bin/bash",
+  "size": 1168776,
+  "type": "file",
+  "name": "bash",
+  "extension": ""
+},
+{
+  "for_packages": [
+    "pkg:deb/debian/gzip@1.9-3?arch=amd64"
+  ],
+  "compliance_alert": "",
+  "path": "/node_16_slim.tar-extract/02c055ef67f5904019f43a41ea5f099996d8e7633749b6e606c400526b2c4b33/bin/uncompress",
+  "size": null,
+  "type": "file",
+  "name": "uncompress",
+  "extension": ""
+}]
+}

tests/test_resource.py

@@ -1325,6 +1325,13 @@ def test_VirtualCodebase_scanning_full_root(self):
         assert "/Users/sesser/code/nexb/scancode-toolkit/samples/README" == resource.path
         assert 1 == codebase.compute_counts()[0]
 
+    def test_VirtualCodebase_can_compute_counts_witrh_null(self):
+        # was failing with 
+        # size_count += child.size
+        # TypeError: unsupported operand type(s) for +=: 'int' and 'NoneType'
+        test_file = self.get_test_loc("resource/virtual_codebase/node-16-slim.json")
+        codebase = VirtualCodebase(test_file)
+        codebase.compute_counts()
 
 class TestResource(FileBasedTesting):
     test_data_dir = join(dirname(__file__), 'data')