addressing new comments from @josenavas @squirrelo

Author: antgonza

qiita_db/data.py

@@ -1268,26 +1268,27 @@ def delete(cls, processed_data_id):
 
         Raises
         ------
-        QiitaDBUnknownIDError
-            If the processed data id doesn't exist
         QiitaDBStatusError
             If the processed data status is not sandbox
+        QiitaDBError
+            If the processed data has (meta)analyses
         """
         if cls(processed_data_id).status != 'sandbox':
             raise QiitaDBStatusError(
                 "Illegal operation on non sandbox processed data")
 
         conn_handler = SQLConnectionHandler()
 
-        analysis_ids = [str(_id[0]) for _id in conn_handler.execute_fetchall(
-            "SELECT DISTINCT analysis_id FROM qiita.analysis_sample WHERE "
-            "processed_data_id = {0} ORDER BY "
-            "analysis_id".format(processed_data_id))]
+        analyses = [str(n[0]) for n in conn_handler.execute_fetchall(
+            "SELECT DISTINCT name FROM qiita.analysis JOIN "
+            "qiita.analysis_sample USING (analysis_id) WHERE "
+            "processed_data_id = {0} ORDER BY name".format(processed_data_id))]
 
-        if analysis_ids:
+        if analyses:
             raise QiitaDBError(
-                "Processed data %d is linked to (meta)analyses: %s" %
-                (processed_data_id, ", ".join(analysis_ids)))
+                "Processed data %d cannot be removed because it is linked to "
+                "the following (meta)analysis: %s" % (processed_data_id,
+                                                      ', '.join(analyses)))
 
         # delete
         queue = "delete_processed_data_%d" % processed_data_id

qiita_db/test/test_data.py

@@ -786,20 +786,28 @@ def test_create(self):
         self.assertEqual(obs, [[1, 2]])
 
     def test_delete(self):
-        """Correctly deletes a processed data and raises an error if it has
-        been used in a (meta)analysis or if it's public"""
+        """Correctly deletes a processed data"""
+        # testing regular delete
         pd = ProcessedData.create(self.params_table, self.params_id,
                                   self.filepaths,
                                   preprocessed_data=self.preprocessed_data,
                                   processed_date=self.date)
         ProcessedData.delete(pd.id)
 
+        # testing that it raises an error if ID doesn't exist
         with self.assertRaises(QiitaDBUnknownIDError):
             ProcessedData.delete(pd.id)
 
+        # testing that we can not remove cause the processed data != sandbox
         with self.assertRaises(QiitaDBStatusError):
             ProcessedData.delete(1)
 
+        # testing that we can not remove cause processed data has analyses
+        pd = ProcessedData(1)
+        pd.status = 'sandbox'
+        with self.assertRaises(QiitaDBError):
+            ProcessedData.delete(1)
+
     def test_create_no_date(self):
         """Correctly adds a processed data with no date on it"""
         # All the other settings have been already tested on test_create