Summary:
Depends on D20185. Ref T13161. Fixes T6791.
See some discusison in T13161. I want to move to a world where:
- whitespace changes are always shown, so users writing YAML and Python are happy without adjusting settings;
- the visual impact of indentation-only whitespace changes is significanlty reduced, so indentation changes are easy to read and users writing Javascript or other flavors of Javascript are happy.
D20181 needs a little more work, but generally tackles these visual changes and lets us always show whitespace changes, but show them in a very low-impact way when they're relatively unimportant.
However, a second aspect to this is how the diff is "aligned". If this file:
```
A
```
..is changed to this file:
```
X
A
Y
Z
```
...diff tools will generally produce this diff:
```
+ X
A
+ Y
+ Z
```
This is good, and easy to read, and what humans expect, and it will "align" in two-up like this:
```
1 X
1 A 2 A
3 Y
4 Z
```
However, if the new file looks like this instead:
```
X
A'
Y
Z
```
...we get a diff like this:
```
- A
+ X
+ A'
+ Y
+ Z
```
This one aligns like this:
```
1 A
1 X
2 A'
3 Y
4 Z
```
This is correct if `A` and `A'` are totally different lines. However, if `A'` is pretty much the same as `A` and it just had a whitespace change, human viewers would prefer this alignment:
```
1 X
1 A 2 A'
3 Y
4 Z
```
Note that `A` and `A'` are different, but we've aligned them on the same line. `diff`, `git diff`, etc., won't do this automatically, and a `.diff` doesn't have a way to say "these lines are more or less the same even though they're different", although some other visual diff tools will do this.
Although `diff` can't do this for us, we can do it ourselves, and already have the code to do it, because we already nearly did this in the changes removed in D20185: in "Ignore All" or "Ignore Most" mode, we pretty much did this already.
This mostly just restores a bit of the code from D20185, with some adjustments/simplifications. Here's how it works:
- Rebuild the text of the old and new files from the diff we got out of `arc`, `git diff`, etc.
- Normalize the files (for example, by removing whitespace from each line).
- Diff the normalized files to produce a second diff.
- Parse that diff.
- Take the "alignment" from the normalized diff (whitespace removed) and the actual text from the original diff (whitespace preserved) to build a new diff with the correct text, but also better diff alignment.
Originally, we normalized with `diff -bw`. I've replaced that with `preg_replace()` here mostly just so that we have more control over things. I believe the two behaviors are pretty much identical, but this way lets us see more of the pipeline and possibly add more behaviors in the future to improve diff quality (e.g., normalize case? normalize text encoding?).
Test Plan:
{F6217133}
(Also, fix a unit test.)
Reviewers: amckinley
Reviewed By: amckinley
Maniphest Tasks: T13161, T6791
Differential Revision: https://secure.phabricator.com/D20187
Summary:
Depends on D20181. Depends on D20182. Fixes T3498. Ref T13161. My claim, at least, is that D20181 can be tweaked to be good enough to throw away this "feature" completely.
I think this feature was sort of a mistake, where the ease of access to `diff -bw` shaped behavior a very long time ago and then the train just ran a long way down the tracks in the same direction.
Test Plan: Grepped for `whitespace`, deleted almost everything. Poked around the UI a bit. I'm expecting the whitespace changes to get some more iteration this week so I not being hugely pedantic about testing this stuff exhaustively.
Reviewers: amckinley
Reviewed By: amckinley
Maniphest Tasks: T13161, T3498
Differential Revision: https://secure.phabricator.com/D20185
Summary:
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.
Test Plan: {F6214084}
Reviewers: amckinley
Reviewed By: amckinley
Maniphest Tasks: T13161
Differential Revision: https://secure.phabricator.com/D20181
Summary:
Ref T2009. This tweaks things a bit more to improve consecuitive groups of added and removed lines.
Generally, it gives us "old, old, old, new, new, new" intead of "old, new, old, new, old, new".
Feelin' real good about having unit tests for this stuff.
Test Plan: Unit tests, looked at diffs in web UI.
Reviewers: btrahan
Reviewed By: btrahan
Subscribers: epriestley
Maniphest Tasks: T2009
Differential Revision: https://secure.phabricator.com/D11994
Summary: This improves some cases with interleaved added and removed lines, and adds test coverage.
Test Plan:
- Added and executed unit tests.
- Viewed raw diff and saw sensible/expected output.
Reviewers: btrahan
Reviewed By: btrahan
Subscribers: epriestley
Differential Revision: https://secure.phabricator.com/D11992
Summary:
See D11468 and D11465. Fixes T5163. Fixes T4105. This makes it practical to test shields, unshielding, moves, etc.
This fixes the issue in D11468, where line maps from whitespace-ignored hunks could have fewer lines than line maps from whitespace-respected hunks, causing a warning.
This encodes the behavior which D11465 changed, making it the canon behavior. Specifically, we do **not** show a shield. I think this is correct. It seems misleading to show "the contents of this file were not changed", because they were changed in both the sense that the file was completely removed, and also changed in the sense that the content itself was (or may have been) changed at the destination. Instead, we just show nothing.
Test Plan:
- Added test coverage.
- Ran tests.
- Used `arc diff --raw --browse` to verify that web behavior was consistent with CLI/test behavior.
Reviewers: joshuaspence, btrahan
Reviewed By: btrahan
Subscribers: epriestley
Maniphest Tasks: T4105, T5163
Differential Revision: https://secure.phabricator.com/D11970
Summary:
Ref T7094. We should do a policy query on the files IMO because there exists a scenario where the file gets locked down directly. This requires being a bit more disciplined about setting user, which in turn requires deciding whether or not to show edit / reply links as a separate piece of logic, not conditional on user presence.
This is not the best code but I don't think it gets worse with this and is just some other nuance in any larger cleanup we take on someday.
Test Plan: looked at a revision and noted inline comments rendered correctly with reply / edit actions. looked at a diff standalone and noted no reply / edit actions as expected. looked at a "details" link on a transaction and it rendered correctly. looked at a diff in phriction of page edits and it looked good. grepped around and verified the remaining callsite in diffusion already has the setUser call.
Reviewers: epriestley
Reviewed By: epriestley
Subscribers: Korvin, epriestley
Maniphest Tasks: T7094
Differential Revision: https://secure.phabricator.com/D11579
Summary: Fixes T6152, T6237. This introduces a viewPolicy column to the DifferentialDiff, and re-jiggers the DifferentialDiff policy implementation such that things behave as before once associated with a revision, else use the DifferentialDiff policy column value.
Test Plan: made a diff with a non-standard view policy and noted that policy was still selected in the revision step. arc lint.
Reviewers: epriestley
Reviewed By: epriestley
Subscribers: Korvin, epriestley
Maniphest Tasks: T6237, T6152
Differential Revision: https://secure.phabricator.com/D10875
Summary:
Provide a viewer to all remarkup engines.
This fixes commit summaries in Diffusion, which were failing to link because they didn't have a user and thus couldn't see/load `D123`, e.g.
Test Plan: Grepped for engine creation.
Reviewers: vrana
Reviewed By: vrana
CC: aran, edward
Maniphest Tasks: T603
Differential Revision: https://secure.phabricator.com/D5152
Summary:
Some transactions (like editing configuration values, task descriptions, or Conpherence images) can't be simply explained and need an additional larger element to show them fully (like a text diff).
Support change details like this in ApplicationTransactions. Implements the element in Config, so you can see changes.
Test Plan: {F32974}
Reviewers: chad
Reviewed By: chad
CC: aran
Maniphest Tasks: T2213
Differential Revision: https://secure.phabricator.com/D4984
Summary:
This is a half-step toward one-up and test renderers. This is mostly a structural change, and has no user-facing impact. It splits the rendering hierarchy like this:
- Renderer (more methods are abstract than before)
- HTML Renderer (most HTML stuff has moved down from the base to here)
- HTML 1-up (placeholder only -- not yet a functional implementation)
- HTML 2-up (minimal changes, uses mostly old code)
- Test Renderer (unit-testable renderer base, implements text versions of the HTML stuff)
- Test 1-up (selects 1-up mode for test rendering)
- Test 2-up (selects 2-up mode for test rendering)
Broadly, I'm trying to share as much code as possible by splitting rendering into more, smaller stages. Specifically, we do this:
- Combine the various sorts of inputs (changes, context, inlines, etc.) into a single, relatively homogenous list of "primitives". This happens in the base class.
- The primitive types are: old (diff left side), new (diff right side), context ("show more context"), no-context ("context not available") and inline (inline comment).
- Possibly, apply a filtering/reordering step to the primitives to get them ready for 1-up rendering. This mostly removes information, and does a small amount of reordering. This also happens in the base class.
- Pass the primitives to the actual renderer, to convert them into HTML, text, or whatever else. This happens in the leaf class.
The primitive implementation is not yet complete (it doesn't attach as much information to the primitives as it should -- stuff like coverage and copies), but covers the basics.
The existing HTMLTwoUp renderer does not use the primitive path; instead, it still goes down the old path.
Test Plan: Ran unit tests, looked at a bunch of diffs.
Reviewers: btrahan
Reviewed By: btrahan
CC: aran
Maniphest Tasks: T2009
Differential Revision: https://secure.phabricator.com/D4421
