gecko/addon-sdk/source/test/test-text-streams.js

155 lines
5.4 KiB
JavaScript

/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
const file = require("sdk/io/file");
const { pathFor } = require("sdk/system");
const { Loader } = require("sdk/test/loader");
const STREAM_CLOSED_ERROR = new RegExp("The stream is closed and cannot be used.");
// This should match the constant of the same name in text-streams.js.
const BUFFER_BYTE_LEN = 0x8000;
exports.testWriteRead = function (assert) {
let fname = dataFileFilename();
// Write a small string less than the stream's buffer size...
let str = "exports.testWriteRead data!";
let stream = file.open(fname, "w");
assert.ok(!stream.closed, "stream.closed after open should be false");
stream.write(str);
stream.close();
assert.ok(stream.closed, "stream.closed after close should be true");
assert.throws(function () stream.close(),
STREAM_CLOSED_ERROR,
"stream.close after already closed should raise error");
assert.throws(function () stream.write("This shouldn't be written!"),
STREAM_CLOSED_ERROR,
"stream.write after close should raise error");
// ... and read it.
stream = file.open(fname);
assert.ok(!stream.closed, "stream.closed after open should be false");
assert.equal(stream.read(), str,
"stream.read should return string written");
assert.equal(stream.read(), "",
"stream.read at EOS should return empty string");
stream.close();
assert.ok(stream.closed, "stream.closed after close should be true");
assert.throws(function () stream.close(),
STREAM_CLOSED_ERROR,
"stream.close after already closed should raise error");
assert.throws(function () stream.read(),
STREAM_CLOSED_ERROR,
"stream.read after close should raise error");
// Write a big string many times the size of the stream's buffer and read it.
// Since it comes after the previous test, this also ensures that the file is
// truncated when it's opened for writing.
str = "";
let bufLen = BUFFER_BYTE_LEN;
let fileSize = bufLen * 10;
for (let i = 0; i < fileSize; i++)
str += i % 10;
stream = file.open(fname, "w");
stream.write(str);
stream.close();
stream = file.open(fname);
assert.equal(stream.read(), str,
"stream.read should return string written");
stream.close();
// The same, but write and read in chunks.
stream = file.open(fname, "w");
let i = 0;
while (i < str.length) {
// Use a chunk length that spans buffers.
let chunk = str.substr(i, bufLen + 1);
stream.write(chunk);
i += bufLen + 1;
}
stream.close();
stream = file.open(fname);
let readStr = "";
bufLen = BUFFER_BYTE_LEN;
let readLen = bufLen + 1;
do {
var frag = stream.read(readLen);
readStr += frag;
} while (frag);
stream.close();
assert.equal(readStr, str,
"stream.write and read in chunks should work as expected");
// Read the same file, passing in strange numbers of bytes to read.
stream = file.open(fname);
assert.equal(stream.read(fileSize * 100), str,
"stream.read with big byte length should return string " +
"written");
stream.close();
stream = file.open(fname);
assert.equal(stream.read(0), "",
"string.read with zero byte length should return empty " +
"string");
stream.close();
stream = file.open(fname);
assert.equal(stream.read(-1), "",
"string.read with negative byte length should return " +
"empty string");
stream.close();
file.remove(fname);
};
exports.testWriteAsync = function (assert, done) {
let fname = dataFileFilename();
let str = "exports.testWriteAsync data!";
let stream = file.open(fname, "w");
assert.ok(!stream.closed, "stream.closed after open should be false");
// Write.
stream.writeAsync(str, function (err) {
assert.equal(this, stream, "|this| should be the stream object");
assert.equal(err, undefined,
"stream.writeAsync should not cause error");
assert.ok(stream.closed, "stream.closed after write should be true");
assert.throws(function () stream.close(),
STREAM_CLOSED_ERROR,
"stream.close after already closed should raise error");
assert.throws(function () stream.writeAsync("This shouldn't work!"),
STREAM_CLOSED_ERROR,
"stream.writeAsync after close should raise error");
// Read.
stream = file.open(fname, "r");
assert.ok(!stream.closed, "stream.closed after open should be false");
let readStr = stream.read();
assert.equal(readStr, str,
"string.read should yield string written");
stream.close();
file.remove(fname);
done();
});
};
exports.testUnload = function (assert) {
let loader = Loader(module);
let file = loader.require("sdk/io/file");
let filename = dataFileFilename("temp");
let stream = file.open(filename, "w");
loader.unload();
assert.ok(stream.closed, "stream should be closed after module unload");
};
// Returns the name of a file that should be used to test writing and reading.
function dataFileFilename() {
return file.join(pathFor("ProfD"), "test-text-streams-data");
}
require('sdk/test').run(exports);