Introduce SonarCloud integration and resolve assorted violations (#575)

list-sonarcloud-profile-modifications.sh

@@ -0,0 +1,44 @@
+#!/usr/bin/env bash
+
+# Compares the `Picnic` SonarCloud quality profile for Java against the default
+# `Sonar way` profile. While the web UI also provides such functionality, this
+# script also compares the configuration parameters of each rule.
+#
+# This script uses `faq`, see https://github.com/jzelinskie/faq.
+
+set -e -u -o pipefail
+
+if [ -z "${SONAR_TOKEN}" ]; then
+  echo 'Environment variable `SONAR_TOKEN` is not set.'
+  exit 1
+fi
+
+export_profile() {
+  local profile="${1}"
+
+  curl --fail --silent --user "${SONAR_TOKEN}:" \
+      "https://sonarcloud.io/api/qualityprofiles/export?qualityProfile=${profile}&language=java&organization=picnic-technologies"
+}
+
+tabulate() {
+  faq --raw-output '
+    def enumerate_params:
+      if .parameters == "" then
+        []
+      elif (.parameters.parameter | type) == "object" then
+        .parameters.parameter | [.key, .value]
+      else
+        .parameters.parameter[] | [.key, .value]
+      end;
+
+    .profile.rules.rule
+      | map([.repositoryKey, .key, .priority] + enumerate_params)
+      | sort
+      | .[]
+      | @tsv
+  ' --output-format json
+}
+
+vimdiff \
+  <(export_profile 'Sonar%20way' | tabulate) \
+  <(export_profile 'Picnic%20Public' | tabulate)