🐛 Bug: Diffs no longer show line changes

[raine]

Update from 2.2.4 to 2.2.5 improved diff color contrast, but lost information on line changes.

Before

After

[a8m]

The string diff of v2.2.4 is actually a regression(see: #1241), but it doesn't change the fact that the reporter loses data.
I'll try to fix it.
Thanks @raine

update: after I tested more deeply, it's seems like it's something belong to diff and how we use it (see: cleanup).

[raine]

No problem. FWIW, I'd prefer to see the strings in style similar to util.inspect as it used to be. It's important to see the difference in detail.

[danielstjules]

This is still the case with 2.3.2:

$ cat test.js
var assert = require('assert');

it('test', function() {
  var a = '1\n2\n3\n';
  var b = '123';

  assert.equal(a, b);
});

$ ./bin/mocha test.js


  ․

  0 passing (6ms)
  1 failing

  1)  test:

      AssertionError: '1\n2\n3\n' == '123'
      + expected - actual

      -1
      -2
      -3
      +123

      ...

cc @mochajs/mocha Any preference here between the two screenshots in the original msg? Is the current output a problem?

[ScottFreeCode]

I very much prefer seeing this:

-1
-2
-3

...over seeing this:

-1\n2\n3\n

The thing I'd consider problematic here is that we can't tell whether there's a trailing newline. What I think we should be seeing is this:

-1
-2
-3
-

(By extension, two \n on the end should result in two - lines, etc. Current behavior is one - for every newline except the last one, which makes one \n and no \n on the end ambiguous; we don't want to fix it only partway and make one \n and two \n ambiguous.)

[boneskull]

not stale