JSTests/stress/jsc-read.js

(function test() {
    // Read this test file using jsc shell's builtins, and check that its content is as expected.
    const in_file = 'jsc-read.js';

    const check = content_read => {
        let expect = '(' + test.toString() + ')();\n';
        if (content_read !== expect)
            throw Error('Expected to read this file as-is, instead read:\n==========\n' + content_read + '\n==========');
    };

    const test_arraybuffer = read_function => {
        let file = read_function(in_file, 'binary');
        if (typeof file.buffer !== 'object' || file.byteLength === undefined || file.length === undefined || file.BYTES_PER_ELEMENT !== 1 || file.byteOffset !== 0)
            throw Error('Expected a Uint8Array');
        let str = '';
        for (var i = 0; i != file.length; ++i)
            str += String.fromCharCode(file[i]);  // Assume ASCII.
        check(str);
    };

    const test_string = read_function => {
        let str = read_function(in_file);
        if (typeof str !== 'string')
            throw Error('Expected a string');
        check(str);
    };

    // jsc's original file reading function is `readFile`, whereas SpiderMonkey
    // shell's file reading function is `read`. The latter is used by
    // emscripten's shell.js (d8 calls it `readbuffer`, which shell.js
    // polyfills).
    test_arraybuffer(readFile);
    test_arraybuffer(read);
    test_string(readFile);
    test_string(read);
})();