Merge pull request #260 from botic/textstream-writable

Better error message if writing read-only streams, fixes #245
ringo · Jun 24, 2014 · f124f26 · f124f26
2 parents a097d69 + 627ef01
commit f124f26
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diff --git a/modules/io.js b/modules/io.js
@@ -481,6 +481,10 @@ exports.TextStream = function TextStream(io, options, buflen) {
      * Writes all arguments to the stream.
      */
     this.write = function () {
+        if (!io.writable()) {
+            throw new Error("The TextStream is not writable!");
+        }
+
         for (var i = 0; i < arguments.length; i++) {
             encoder.encode(String(arguments[i]));
         }

diff --git a/test/io_test.js b/test/io_test.js
@@ -56,6 +56,24 @@ exports.testTextStream = function() {
 
     assert.strictEqual(lines[0], "Hello\n");
     assert.strictEqual(lines[1], "World!");
+
+    // Try to write a read-only stream
+    try {
+        stream.writeLine("Hello World!");
+        assert.fail("writeLine() should throw an error!");
+    } catch (err) {
+        assert.strictEqual(err.name, "Error");
+        assert.strictEqual(err.message, "The TextStream is not writable!");
+    }
+    stream.close();
+
+    // Check writing
+    var output = new java.io.ByteArrayOutputStream();
+    stream = new TextStream(new Stream(output));
+    stream.writeLine("Hello");
+    stream.write("World!");
+    stream.close();
+    assert.strictEqual(output.toString(), "Hello\nWorld!");
 };
 
 if (module == require.main) {