From bc5eafb19bf71141b88dff749240354898849a66 Mon Sep 17 00:00:00 2001
From: Tobias Sorn <tobias.sorn@sap.com>
Date: Wed, 24 Jun 2020 09:32:41 +0200
Subject: [PATCH] [FIX] Resource: getStream for empty string (#249)

When a Resource is created parameter `string` can be passed.
For an empty string `""` calling Resource#getStream
threw an error:  `Resource ${this._path} has no content`

Now the empty string is properly set and the stream can be retrieved.
---
 lib/Resource.js      |  2 +-
 test/lib/Resource.js | 59 ++++++++++++++++++++++++++++++++++++--------
 2 files changed, 50 insertions(+), 11 deletions(-)

diff --git a/lib/Resource.js b/lib/Resource.js
index 14d3737a..860b68e6 100644
--- a/lib/Resource.js
+++ b/lib/Resource.js
@@ -73,7 +73,7 @@ class Resource {
 		this._createStream = createStream || null;
 		this._stream = stream || null;
 		this._buffer = buffer || null;
-		if (string) {
+		if (typeof string === "string" || string instanceof String) {
 			this._buffer = Buffer.from(string, "utf8");
 		}
 
diff --git a/test/lib/Resource.js b/test/lib/Resource.js
index 818c0591..c2400601 100644
--- a/test/lib/Resource.js
+++ b/test/lib/Resource.js
@@ -18,6 +18,27 @@ function createBasicResource() {
 	return resource;
 }
 
+/**
+ * Reads a readable stream and resolves with its content
+ *
+ * @param {stream.Readable} readableStream readable stream
+ * @returns {Promise<string>} resolves with the read string
+ */
+const readStream = (readableStream) => {
+	return new Promise((resolve, reject) => {
+		let streamedResult = "";
+		readableStream.on("data", (chunk) => {
+			streamedResult += chunk;
+		});
+		readableStream.on("end", () => {
+			resolve(streamedResult);
+		});
+		readableStream.on("error", (err) => {
+			reject(err);
+		});
+	});
+};
+
 test("Resource: constructor with missing path parameter", (t) => {
 	t.throws(() => {
 		new Resource({});
@@ -62,20 +83,38 @@ test("Resource: getStream", async (t) => {
 		buffer: Buffer.from("Content")
 	});
 
-	return new Promise(function(resolve, reject) {
-		let streamedResult = "";
-		const readableStream = resource.getStream();
-		readableStream.on("data", (chunk) => {
-			streamedResult += chunk;
-		});
-		readableStream.on("end", () => {
-			resolve(streamedResult);
-		});
-	}).then((result) => {
+	return readStream(resource.getStream()).then((result) => {
 		t.is(result, "Content", "Stream has been read correctly");
 	});
 });
 
+test("Resource: getStream for empty string", async (t) => {
+	t.plan(1);
+
+	const resource = new Resource({
+		path: "my/path/to/resource",
+		string: ""
+	});
+
+	return readStream(resource.getStream()).then((result) => {
+		t.is(result, "", "Stream has been read correctly for empty string");
+	});
+});
+
+test("Resource: getStream for empty string instance", async (t) => {
+	t.plan(1);
+
+	const resource = new Resource({
+		path: "my/path/to/resource",
+		// eslint-disable-next-line no-new-wrappers
+		string: new String("")
+	});
+
+	return readStream(resource.getStream()).then((result) => {
+		t.is(result, "", "Stream has been read correctly for empty string");
+	});
+});
+
 test("Resource: getStream throwing an error", (t) => {
 	const resource = new Resource({
 		path: "my/path/to/resource"