Add Python html_diff module.

Add Python html_diff module.

This CL adds a module which is intended to produce simple HTML
diffs to view with layout test results.

BUG=672651
Committed: https://crrev.com/78fa99563509c4f515b37d228f1f93a7f9c1300b
Cr-Commit-Position: refs/heads/master@{#439516}

[qyearsley, 2016-12-17 00:15:33]

qyearsley@chromium.org changed reviewers:
+ dpranke@chromium.org

[estaab, 2016-12-17 18:26:14]

estaab@chromium.org changed reviewers:
+ estaab@chromium.org

[estaab, 2016-12-17 18:26:15]

lgtm

Maybe add a note that this isn't efficient with memory and shouldn't be used for
large files.

[qyearsley, 2016-12-17 20:16:53]

On 2016/12/17 at 18:26:15, estaab wrote:
> lgtm
> 
> Maybe add a note that this isn't efficient with memory and shouldn't be used
for large files.

Currently there's a note at the top that says:
  "The main purpose of this utility is to show the difference between
   text baselines (-expected.txt files) and actual text results."
Do you think it's helpful to add another sentence there?

As-is, using this module involves having the content of both input files and
output files in
memory at the same time, so that when it's used in test_result_writer.py, it can
be invoked as:

  html_diff_contents = html_diff(expected_text, actual_text)
  self._write_file(html_diff_filename, html_diff_contents)

Might it be worth it to think about writing the file as we go?

[qyearsley, 2016-12-17 20:16:53]

On 2016/12/17 at 18:26:15, estaab wrote:
> lgtm
> 
> Maybe add a note that this isn't efficient with memory and shouldn't be used
for large files.

Currently there's a note at the top that says:
  "The main purpose of this utility is to show the difference between
   text baselines (-expected.txt files) and actual text results."
Do you think it's helpful to add another sentence there?

As-is, using this module involves having the content of both input files and
output files in
memory at the same time, so that when it's used in test_result_writer.py, it can
be invoked as:

  html_diff_contents = html_diff(expected_text, actual_text)
  self._write_file(html_diff_filename, html_diff_contents)

Might it be worth it to think about writing the file as we go?

[Dirk Pranke, 2016-12-18 03:13:30]

lgtm

[qyearsley, 2016-12-19 17:56:44]

The CQ bit was checked by qyearsley@chromium.org

[commit-bot: I haz the power, 2016-12-19 17:57:04]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-12-19 19:04:31]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1482170204433180, "parent_rev":
"56bedb351a7b230217bfeda6bb07d3d81af60387", "commit_rev":
"c2d756c285006e9e49542f09907c5d04735030ce"}

[commit-bot: I haz the power, 2016-12-19 19:05:02]

Description was changed from

==========
Add Python html_diff module.

This CL adds a module which is intended to produce simple HTML
diffs to view with layout test results.

BUG=672651
==========

to

==========
Add Python html_diff module.

This CL adds a module which is intended to produce simple HTML
diffs to view with layout test results.

BUG=672651

Review-Url: https://codereview.chromium.org/2580143002
==========

[commit-bot: I haz the power, 2016-12-19 19:05:03]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-12-19 19:07:08]

Description was changed from

==========
Add Python html_diff module.

This CL adds a module which is intended to produce simple HTML
diffs to view with layout test results.

BUG=672651

Review-Url: https://codereview.chromium.org/2580143002
==========

to

==========
Add Python html_diff module.

This CL adds a module which is intended to produce simple HTML
diffs to view with layout test results.

BUG=672651

Committed: https://crrev.com/78fa99563509c4f515b37d228f1f93a7f9c1300b
Cr-Commit-Position: refs/heads/master@{#439516}
==========

[commit-bot: I haz the power, 2016-12-19 19:07:09]

Patchset 1 (id:??) landed as
https://crrev.com/78fa99563509c4f515b37d228f1f93a7f9c1300b
Cr-Commit-Position: refs/heads/master@{#439516}