From edb6918c6ac37b5d17ef4819204886d3ac21eb2a Mon Sep 17 00:00:00 2001
From: Mike Ralphson <mike.ralphson@gmail.com>
Date: Thu, 6 Dec 2018 00:09:48 +0000
Subject: [PATCH] rewrite const as single element enum

---
 index.js           | 11 +++++++++++
 test/const.test.js | 21 +++++++++++++++++++++
 2 files changed, 32 insertions(+)
 create mode 100644 test/const.test.js

diff --git a/index.js b/index.js
index f89c908..af590c1 100644
--- a/index.js
+++ b/index.js
@@ -29,6 +29,7 @@ function stripIllegalKeywords(schema) {
 function convertSchema(schema, path, parent, parentPath) {
 	schema = stripIllegalKeywords(schema);
 	schema = convertTypes(schema);
+	schema = rewriteConst(schema);
 	schema = convertDependencies(schema);
 
 	if (typeof schema['patternProperties'] === 'object') {
@@ -137,7 +138,17 @@ function convertTypes(schema) {
 function convertPatternProperties(schema) {
 	schema['x-patternProperties'] = schema['patternProperties'];
 	delete schema['patternProperties'];
+	if (typeof schema.additionalProperties === 'undefined') schema.additionalProperties = true;
+	return schema;
+}
+
+function rewriteConst(schema) {
+	if (schema.const) {
+		schema.enum = [ schema.const ];
+		delete schema.const;
+	}
 	return schema;
 }
 
 module.exports = convert;
+
diff --git a/test/const.test.js b/test/const.test.js
new file mode 100644
index 0000000..be0ca20
--- /dev/null
+++ b/test/const.test.js
@@ -0,0 +1,21 @@
+'use strict';
+
+const convert = require('../');
+const should = require('should');
+
+it('const', () => {
+	const schema = {
+		$schema: 'http://json-schema.org/draft-04/schema#',
+		type: 'string',
+		const: 'hello'
+	};
+
+	const result = convert(schema);
+
+	const expected = {
+		type: 'string',
+		enum: [ 'hello' ]
+	};
+
+	should(result).deepEqual(expected, 'converted');
+});