test: clean up / refactor buffer tests, remove duplication

Remove duplication of buffer tests, separate out into separate
files, update and cleanup code, move to using strictEqual where
possible.

PR-URL: nodejs#8256
Reviewed-By: Michaël Zasso <mic.besace@gmail.com>

 Conflicts:
	test/parallel/test-buffer-alloc.js
	test/parallel/test-buffer.js
	test/parallel/test-buffer-no-negative-allocation.js

test/parallel/test-buffer-compare.js

@@ -0,0 +1,30 @@
+'use strict';
+
+require('../common');
+const assert = require('assert');
+
+const b = Buffer.alloc(1, 'a');
+const c = Buffer.alloc(1, 'c');
+const d = Buffer.alloc(2, 'aa');
+
+assert.strictEqual(b.compare(c), -1);
+assert.strictEqual(c.compare(d), 1);
+assert.strictEqual(d.compare(b), 1);
+assert.strictEqual(b.compare(d), -1);
+assert.strictEqual(b.compare(b), 0);
+
+assert.strictEqual(Buffer.compare(b, c), -1);
+assert.strictEqual(Buffer.compare(c, d), 1);
+assert.strictEqual(Buffer.compare(d, b), 1);
+assert.strictEqual(Buffer.compare(b, d), -1);
+assert.strictEqual(Buffer.compare(c, c), 0);
+
+assert.strictEqual(Buffer.compare(Buffer.alloc(0), Buffer.alloc(0)), 0);
+assert.strictEqual(Buffer.compare(Buffer.alloc(0), Buffer.alloc(1)), -1);
+assert.strictEqual(Buffer.compare(Buffer.alloc(1), Buffer.alloc(0)), 1);
+
+assert.throws(() => Buffer.compare(Buffer.alloc(1), 'abc'));
+
+assert.throws(() => Buffer.compare('abc', Buffer.alloc(1)));
+
+assert.throws(() => Buffer.alloc(1).compare('abc'));

test/parallel/test-buffer-copy.js

@@ -0,0 +1,120 @@
+'use strict';
+
+require('../common');
+const assert = require('assert');
+
+var b = Buffer.allocUnsafe(1024);
+var c = Buffer.allocUnsafe(512);
+var cntr = 0;
+
+{
+  // copy 512 bytes, from 0 to 512.
+  b.fill(++cntr);
+  c.fill(++cntr);
+  const copied = b.copy(c, 0, 0, 512);
+  assert.strictEqual(512, copied);
+  for (let i = 0; i < c.length; i++) {
+    assert.strictEqual(b[i], c[i]);
+  }
+}
+
+{
+  // copy c into b, without specifying sourceEnd
+  b.fill(++cntr);
+  c.fill(++cntr);
+  const copied = c.copy(b, 0, 0);
+  assert.strictEqual(c.length, copied);
+  for (let i = 0; i < c.length; i++) {
+    assert.strictEqual(c[i], b[i]);
+  }
+}
+
+{
+  // copy c into b, without specifying sourceStart
+  b.fill(++cntr);
+  c.fill(++cntr);
+  const copied = c.copy(b, 0);
+  assert.strictEqual(c.length, copied);
+  for (let i = 0; i < c.length; i++) {
+    assert.strictEqual(c[i], b[i]);
+  }
+}
+
+{
+  // copy longer buffer b to shorter c without targetStart
+  b.fill(++cntr);
+  c.fill(++cntr);
+  const copied = b.copy(c);
+  assert.strictEqual(c.length, copied);
+  for (let i = 0; i < c.length; i++) {
+    assert.strictEqual(b[i], c[i]);
+  }
+}
+
+{
+  // copy starting near end of b to c
+  b.fill(++cntr);
+  c.fill(++cntr);
+  const copied = b.copy(c, 0, b.length - Math.floor(c.length / 2));
+  assert.strictEqual(Math.floor(c.length / 2), copied);
+  for (let i = 0; i < Math.floor(c.length / 2); i++) {
+    assert.strictEqual(b[b.length - Math.floor(c.length / 2) + i], c[i]);
+  }
+  for (let i = Math.floor(c.length / 2) + 1; i < c.length; i++) {
+    assert.strictEqual(c[c.length - 1], c[i]);
+  }
+}
+
+{
+  // try to copy 513 bytes, and check we don't overrun c
+  b.fill(++cntr);
+  c.fill(++cntr);
+  const copied = b.copy(c, 0, 0, 513);
+  assert.strictEqual(c.length, copied);
+  for (let i = 0; i < c.length; i++) {
+    assert.strictEqual(b[i], c[i]);
+  }
+}
+
+{
+  // copy 768 bytes from b into b
+  b.fill(++cntr);
+  b.fill(++cntr, 256);
+  const copied = b.copy(b, 0, 256, 1024);
+  assert.strictEqual(768, copied);
+  for (let i = 0; i < b.length; i++) {
+    assert.strictEqual(cntr, b[i]);
+  }
+}
+
+// copy string longer than buffer length (failure will segfault)
+var bb = Buffer.allocUnsafe(10);
+bb.fill('hello crazy world');
+
+
+// try to copy from before the beginning of b
+assert.doesNotThrow(() => { b.copy(c, 0, 100, 10); });
+
+// copy throws at negative sourceStart
+assert.throws(function() {
+  Buffer.allocUnsafe(5).copy(Buffer.allocUnsafe(5), 0, -1);
+}, RangeError);
+
+{
+  // check sourceEnd resets to targetEnd if former is greater than the latter
+  b.fill(++cntr);
+  c.fill(++cntr);
+  b.copy(c, 0, 0, 1025);
+  for (let i = 0; i < c.length; i++) {
+    assert.strictEqual(b[i], c[i]);
+  }
+}
+
+// throw with negative sourceEnd
+assert.throws(() => b.copy(c, 0, 0, -1), RangeError);
+
+// when sourceStart is greater than sourceEnd, zero copied
+assert.strictEqual(b.copy(c, 0, 100, 10), 0);
+
+// when targetStart > targetLength, zero copied
+assert.strictEqual(b.copy(c, 512, 0, 10), 0);

test/parallel/test-buffer-equals.js

@@ -0,0 +1,16 @@
+'use strict';
+
+require('../common');
+const assert = require('assert');
+
+const b = Buffer.from('abcdf');
+const c = Buffer.from('abcdf');
+const d = Buffer.from('abcde');
+const e = Buffer.from('abcdef');
+
+assert.ok(b.equals(c));
+assert.ok(!c.equals(d));
+assert.ok(!d.equals(e));
+assert.ok(d.equals(d));
+
+assert.throws(() => Buffer.alloc(1).equals('abc'));

test/parallel/test-buffer-failed-alloc-typed-arrays.js

@@ -0,0 +1,33 @@
+'use strict';
+
+require('../common');
+const assert = require('assert');
+const SlowBuffer = require('buffer').SlowBuffer;
+
+// Test failed or zero-sized Buffer allocations not affecting typed arrays.
+// This test exists because of a regression that occurred. Because Buffer
+// instances are allocated with the same underlying allocator as TypedArrays,
+// but Buffer's can optional be non-zero filled, there was a regression that
+// occurred when a Buffer allocated failed, the internal flag specifying
+// whether or not to zero-fill was not being reset, causing TypedArrays to
+// allocate incorrectly.
+const zeroArray = new Uint32Array(10).fill(0);
+const sizes = [1e10, 0, 0.1, -1, 'a', undefined, null, NaN];
+const allocators = [
+  Buffer,
+  SlowBuffer,
+  Buffer.alloc,
+  Buffer.allocUnsafe,
+  Buffer.allocUnsafeSlow
+];
+for (const allocator of allocators) {
+  for (const size of sizes) {
+    try {
+      // These allocations are known to fail. If they do,
+      // Uint32Array should still produce a zeroed out result.
+      allocator(size);
+    } catch (e) {
+      assert.deepStrictEqual(new Uint32Array(10), zeroArray);
+    }
+  }
+}

test/parallel/test-buffer-fill.js

@@ -267,3 +267,50 @@ function testBufs(string, offset, length, encoding) {
   assert.deepStrictEqual(buf1.fill.apply(buf1, arguments),
                          writeToFill.apply(null, arguments));
 }
+
+// Make sure these throw.
+assert.throws(() => Buffer.allocUnsafe(8).fill('a', -1));
+assert.throws(() => Buffer.allocUnsafe(8).fill('a', 0, 9));
+
+// Make sure this doesn't hang indefinitely.
+Buffer.allocUnsafe(8).fill('');
+Buffer.alloc(8, '');
+
+{
+  const buf = Buffer.alloc(64, 10);
+  for (let i = 0; i < buf.length; i++)
+    assert.strictEqual(buf[i], 10);
+
+  buf.fill(11, 0, buf.length >> 1);
+  for (let i = 0; i < buf.length >> 1; i++)
+    assert.strictEqual(buf[i], 11);
+  for (let i = (buf.length >> 1) + 1; i < buf.length; i++)
+    assert.strictEqual(buf[i], 10);
+
+  buf.fill('h');
+  for (let i = 0; i < buf.length; i++)
+    assert.strictEqual('h'.charCodeAt(0), buf[i]);
+
+  buf.fill(0);
+  for (let i = 0; i < buf.length; i++)
+    assert.strictEqual(0, buf[i]);
+
+  buf.fill(null);
+  for (let i = 0; i < buf.length; i++)
+    assert.strictEqual(0, buf[i]);
+
+  buf.fill(1, 16, 32);
+  for (let i = 0; i < 16; i++)
+    assert.strictEqual(0, buf[i]);
+  for (let i = 16; i < 32; i++)
+    assert.strictEqual(1, buf[i]);
+  for (let i = 32; i < buf.length; i++)
+    assert.strictEqual(0, buf[i]);
+}
+
+{
+  const buf = Buffer.alloc(10, 'abc');
+  assert.strictEqual(buf.toString(), 'abcabcabca');
+  buf.fill('է');
+  assert.strictEqual(buf.toString(), 'էէէէէ');
+}

test/parallel/test-buffer-isencoding.js

@@ -0,0 +1,33 @@
+'use strict';
+
+require('../common');
+const assert = require('assert');
+
+[ 'hex',
+  'utf8',
+  'utf-8',
+  'ascii',
+  'latin1',
+  'binary',
+  'base64',
+  'ucs2',
+  'ucs-2',
+  'utf16le',
+  'utf-16le' ].forEach((enc) => {
+    assert.strictEqual(Buffer.isEncoding(enc), true);
+  });
+
+[ 'utf9',
+  'utf-7',
+  'Unicode-FTW',
+  'new gnu gun',
+  false,
+  NaN,
+  {},
+  Infinity,
+  [],
+  1,
+  0,
+  -1 ].forEach((enc) => {
+    assert.strictEqual(Buffer.isEncoding(enc), false);
+  });

test/parallel/test-buffer-regression-649.js

@@ -0,0 +1,13 @@
+'use strict';
+
+require('../common');
+const assert = require('assert');
+const SlowBuffer = require('buffer').SlowBuffer;
+
+// Regression test for https://github.com/nodejs/node/issues/649.
+const len = 1422561062959;
+assert.throws(() => Buffer(len).toString('utf8'));
+assert.throws(() => SlowBuffer(len).toString('utf8'));
+assert.throws(() => Buffer.alloc(len).toString('utf8'));
+assert.throws(() => Buffer.allocUnsafe(len).toString('utf8'));
+assert.throws(() => Buffer.allocUnsafeSlow(len).toString('utf8'));

test/parallel/test-buffer-slice.js

@@ -0,0 +1,63 @@
+'use strict';
+
+require('../common');
+const assert = require('assert');
+
+assert.strictEqual(0, Buffer.from('hello').slice(0, 0).length);
+assert.strictEqual(0, Buffer('hello').slice(0, 0).length);
+
+const buf = Buffer.from('0123456789');
+assert.equal(buf.slice(-10, 10), '0123456789');
+assert.equal(buf.slice(-20, 10), '0123456789');
+assert.equal(buf.slice(-20, -10), '');
+assert.equal(buf.slice(), '0123456789');
+assert.equal(buf.slice(0), '0123456789');
+assert.equal(buf.slice(0, 0), '');
+assert.equal(buf.slice(undefined), '0123456789');
+assert.equal(buf.slice('foobar'), '0123456789');
+assert.equal(buf.slice(undefined, undefined), '0123456789');
+
+assert.equal(buf.slice(2), '23456789');
+assert.equal(buf.slice(5), '56789');
+assert.equal(buf.slice(10), '');
+assert.equal(buf.slice(5, 8), '567');
+assert.equal(buf.slice(8, -1), '8');
+assert.equal(buf.slice(-10), '0123456789');
+assert.equal(buf.slice(0, -9), '0');
+assert.equal(buf.slice(0, -10), '');
+assert.equal(buf.slice(0, -1), '012345678');
+assert.equal(buf.slice(2, -2), '234567');
+assert.equal(buf.slice(0, 65536), '0123456789');
+assert.equal(buf.slice(65536, 0), '');
+assert.equal(buf.slice(-5, -8), '');
+assert.equal(buf.slice(-5, -3), '56');
+assert.equal(buf.slice(-10, 10), '0123456789');
+for (let i = 0, s = buf.toString(); i < buf.length; ++i) {
+  assert.equal(buf.slice(i), s.slice(i));
+  assert.equal(buf.slice(0, i), s.slice(0, i));
+  assert.equal(buf.slice(-i), s.slice(-i));
+  assert.equal(buf.slice(0, -i), s.slice(0, -i));
+}
+
+const utf16Buf = Buffer.from('0123456789', 'utf16le');
+assert.deepStrictEqual(utf16Buf.slice(0, 6), Buffer.from('012', 'utf16le'));
+
+assert.equal(buf.slice('0', '1'), '0');
+assert.equal(buf.slice('-5', '10'), '56789');
+assert.equal(buf.slice('-10', '10'), '0123456789');
+assert.equal(buf.slice('-10', '-5'), '01234');
+assert.equal(buf.slice('-10', '-0'), '');
+assert.equal(buf.slice('111'), '');
+assert.equal(buf.slice('0', '-111'), '');
+
+// try to slice a zero length Buffer
+// see https://github.com/joyent/node/issues/5881
+Buffer.alloc(0).slice(0, 1);
+
+{
+  // Single argument slice
+  assert.strictEqual('bcde', Buffer.from('abcde').slice(1).toString());
+}
+
+// slice(0,0).length === 0
+assert.strictEqual(0, Buffer.from('hello').slice(0, 0).length);