From fb5be0a84e9b7c0eec30e5d2bbadd1bec0951d3d Mon Sep 17 00:00:00 2001
From: Jason Scott <dev.jason.scott@gmail.com>
Date: Sat, 2 Feb 2019 15:16:35 +0100
Subject: [PATCH] Switches nil values to delete columns instead of filling with
 empty string. Change made to integrate better with BigQuery adapter in short
 term

---
 lib/typed/mutations.ex        | 14 ++++++--
 test/typed/mutations_test.exs | 64 ++++++++++++++++++++++++++++++++++-
 2 files changed, 75 insertions(+), 3 deletions(-)

diff --git a/lib/typed/mutations.ex b/lib/typed/mutations.ex
index 164197f..accd3d9 100644
--- a/lib/typed/mutations.ex
+++ b/lib/typed/mutations.ex
@@ -36,11 +36,21 @@ defmodule Bigtable.Typed.Mutations do
 
         _ ->
           accum
-          |> Bigtable.Mutations.set_cell(family_name, column_qualifier, v)
+          |> add_cell_mutation(family_name, column_qualifier, v)
       end
     end)
   end
 
+  defp add_cell_mutation(accum, family_name, column_qualifier, nil) do
+    accum
+    |> Bigtable.Mutations.delete_from_column(family_name, column_qualifier)
+  end
+
+  defp add_cell_mutation(accum, family_name, column_qualifier, value) do
+    accum
+    |> Bigtable.Mutations.set_cell(family_name, column_qualifier, value)
+  end
+
   defp nested_map(type, value, accum, family_name, column_qualifier) do
     if value == nil or value == "" do
       niled_map = nil_values(type)
@@ -55,7 +65,7 @@ defmodule Bigtable.Typed.Mutations do
       if is_map(v) do
         Map.put(accum, k, nil_values(v))
       else
-        Map.put(accum, k, "")
+        Map.put(accum, k, nil)
       end
     end)
   end
diff --git a/test/typed/mutations_test.exs b/test/typed/mutations_test.exs
index 64d785a..9c0f251 100644
--- a/test/typed/mutations_test.exs
+++ b/test/typed/mutations_test.exs
@@ -53,7 +53,69 @@ defmodule TypedMutationsTest do
         }
       }
 
-      expected = expected_entry("", "")
+      expected = %Google.Bigtable.V2.MutateRowsRequest.Entry{
+        row_key: "Test#1",
+        mutations: [
+          %Google.Bigtable.V2.Mutation{
+            mutation:
+              {:set_cell,
+               %Google.Bigtable.V2.Mutation.SetCell{
+                 column_qualifier: "test_column",
+                 family_name: "test_family",
+                 timestamp_micros: -1,
+                 value: "false"
+               }}
+          },
+          %Google.Bigtable.V2.Mutation{
+            mutation:
+              {:delete_from_column,
+               %Google.Bigtable.V2.Mutation.DeleteFromColumn{
+                 column_qualifier: "test_nested.double_nested.double_nested_a",
+                 family_name: "test_family",
+                 time_range: %Google.Bigtable.V2.TimestampRange{
+                   end_timestamp_micros: 0,
+                   start_timestamp_micros: 0
+                 }
+               }}
+          },
+          %Google.Bigtable.V2.Mutation{
+            mutation:
+              {:delete_from_column,
+               %Google.Bigtable.V2.Mutation.DeleteFromColumn{
+                 column_qualifier: "test_nested.double_nested.double_nested_b",
+                 family_name: "test_family",
+                 time_range: %Google.Bigtable.V2.TimestampRange{
+                   end_timestamp_micros: 0,
+                   start_timestamp_micros: 0
+                 }
+               }}
+          },
+          %Google.Bigtable.V2.Mutation{
+            mutation:
+              {:delete_from_column,
+               %Google.Bigtable.V2.Mutation.DeleteFromColumn{
+                 column_qualifier: "test_nested.nested_a",
+                 family_name: "test_family",
+                 time_range: %Google.Bigtable.V2.TimestampRange{
+                   end_timestamp_micros: 0,
+                   start_timestamp_micros: 0
+                 }
+               }}
+          },
+          %Google.Bigtable.V2.Mutation{
+            mutation:
+              {:delete_from_column,
+               %Google.Bigtable.V2.Mutation.DeleteFromColumn{
+                 column_qualifier: "test_nested.nested_b",
+                 family_name: "test_family",
+                 time_range: %Google.Bigtable.V2.TimestampRange{
+                   end_timestamp_micros: 0,
+                   start_timestamp_micros: 0
+                 }
+               }}
+          }
+        ]
+      }
 
       result = Mutations.create_mutations(context.row_key, context.type_spec, map)