feat(app): add a test on `snakeToCamel`

tests/tools/private/pre-commit

 #!/usr/bin/sh
 
+RED='\e[1;31m'
+GREEN='\e[1;32m'
+BLUE='\e[1;34m'
+NC='\e[0m'
+
+# Check QML files, quit on failure.
 sh "./tests/tools/check_qml"
 
-exit $?
+if [[ $? != 0 ]] ; then
+    exit 1
+fi
+
+# Check JS lib.
+printf "${BLUE}Testing scripts lib...${NC}\n"
+
+so_far_so_good=0
+qmltestrunner -input "./tests/ui/scripts/Utils/utils.spec.qml"
+
+if [[ $? == 0 ]]; then
+    printf "${GREEN}Done. No error found in scripts lib.\n"
+else
+    printf "${RED}One or more errors were found. Please to fix them.\n"
+    so_far_so_good=1
+fi
+printf "${NC}"
+
+exit $so_far_so_good

tests/ui/scripts/Utils/utils.spec.qml

+import QtQuick 2.7
+import QtTest 1.1
+
+// Explicit import, `utils.js` is not accessible in resources file
+// when tests are executed.
+import './utils.js' as Utils
+
+TestCase {
+  name: 'UtilsTests'
+
+  function test_snakeToCamel_data () {
+    return [
+      { input: 'foo_bar', output: 'fooBar' },
+      { input: 'george_abitbol', output: 'georgeAbitbol' },
+      { input: 'billTremendousAndHubert', output: 'billTremendousAndHubert' },
+      { input: 'foo_bAr_BAZ', output: 'fooBArBAZ' },
+    ]
+  }
+
+  function test_snakeToCamel (data) {
+    compare(Utils.snakeToCamel(data.input), data.output)
+  }
+}