Implements tests regression tool

scripts/test_regression.sh

@@ -0,0 +1,22 @@
+#!/usr/bin/env bash
+
+function get_current_coverage {
+    local prev_stat_raw=`TEST_DB_URI=${TEST_DB_URI} tox -e py35-functional | grep TOTAL | awk '{print $4}'`
+    echo ${prev_stat_raw:0:2}
+}
+
+function get_coverage_delta {
+    local current_coverage=$(get_current_coverage)
+    local current_branch=`git branch | awk '{print $2}'`
+    git checkout `git rev-parse --verify HEAD^${1:-1}`
+    local prev_coverage=$(get_current_coverage)
+    if [ "${prev_coverage}" -gt "${current_coverage}" ]; then
+        echo -e "Test regression found.\n Current commit: ${current_coverage} \Previous commit: ${prev_coverage}."
+        git checkout ${current_branch}
+        exit 1
+    fi
+    git checkout ${current_branch}
+}
+
+
+get_coverage_delta ${1:-1}