Change Details

Ref T13161. See PHI723. Our whitespace handling is based on whitespace flags like `diff -bw`, mostly just for historical reasons: long ago, the easiest way to minimize the visual impact of indentation changes was to literally use `diff -bw`. However, this approach is very coarse and has a lot of problems, like detecting `"ab" -> "a b"` as "only a whitespace change" even though this is always semantic. It also causes problems in YML, Python, etc. Over time, we've added a lot of stuff to mitigate the downsides to this approach. We also no longer get any benefits from this approach being simple: we need faithful diffs as the authoritative source, and have to completely rebuild the diff to `diff -bw` it. In the UI, we have a "whitespace mode" flag. We have the "whitespace matters" configuration. I think ReviewBoard generally has a better approach to indent depth changes than we do (see T13161) where it detects them and renders them in a minimal way with low visual impact. This is ultimately what we want: reduce visual clutter for depth-only changes, but preserve whitespace changes in strings, etc. Move toward detecting and rendering indent depth changes. Followup work: - These should get colorblind colors and the design can probably use a little more tweaking. - The OneUp mode is okay, but could be improved. - Whitespace mode can now be removed completely. - I'm trying to handle tabs correctly, but since we currently mangle them into spaces today, it's hard to be sure I actually got it right.

Ref T13161. See PHI723. Our whitespace handling is based on whitespace flags like `diff -bw`, mostly just for historical reasons: long ago, the easiest way to minimize the visual impact of indentation changes was to literally use `diff -bw`. However, this approach is very coarse and has a lot of problems, like detecting `"ab" -> "a b"` as "only a whitespace change" even though this is always semantic. It also causes problems in YAML, Python, etc. Over time, we've added a lot of stuff to mitigate the downsides to this approach. We also no longer get any benefits from this approach being simple: we need faithful diffs as the authoritative source, and have to completely rebuild the diff to `diff -bw` it. In the UI, we have a "whitespace mode" flag. We have the "whitespace matters" configuration. I think ReviewBoard generally has a better approach to indent depth changes than we do (see T13161) where it detects them and renders them in a minimal way with low visual impact. This is ultimately what we want: reduce visual clutter for depth-only changes, but preserve whitespace changes in strings, etc. Move toward detecting and rendering indent depth changes. Followup work: - These should get colorblind colors and the design can probably use a little more tweaking. - The OneUp mode is okay, but could be improved. - Whitespace mode can now be removed completely. - I'm trying to handle tabs correctly, but since we currently mangle them into spaces today, it's hard to be sure I actually got it right.

Ref T13161. See PHI723. Our whitespace handling is based on whitespace flags like `diff -bw`, mostly just for historical reasons: long ago, the easiest way to minimize the visual impact of indentation changes was to literally use `diff -bw`. However, this approach is very coarse and has a lot of problems, like detecting `"ab" -> "a b"` as "only a whitespace change" even though this is always semantic. It also causes problems in YAML, Python, etc. Over time, we've added a lot of stuff to mitigate the downsides to this approach. We also no longer get any benefits from this approach being simple: we need faithful diffs as the authoritative source, and have to completely rebuild the diff to `diff -bw` it. In the UI, we have a "whitespace mode" flag. We have the "whitespace matters" configuration. I think ReviewBoard generally has a better approach to indent depth changes than we do (see T13161) where it detects them and renders them in a minimal way with low visual impact. This is ultimately what we want: reduce visual clutter for depth-only changes, but preserve whitespace changes in strings, etc. Move toward detecting and rendering indent depth changes. Followup work: - These should get colorblind colors and the design can probably use a little more tweaking. - The OneUp mode is okay, but could be improved. - Whitespace mode can now be removed completely. - I'm trying to handle tabs correctly, but since we currently mangle them into spaces today, it's hard to be sure I actually got it right.