Add sidebar with GUI filters to the search results page

[axispx]

This PR adds interactive filters in the sidebar to filter between repositories and languages.

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[axispx]

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[hanwen]

nice!

I usually do the reviews from Gerrit though - see CONTRIBUTING. Would you mind sending me a change there instead?

[axispx]

There's an error adding my GitHub email address so I'm unable to push the changes to Gerrit.

[hanwen]

I had a quick look at this last week. I have two complaints:

• the left nav doesnt scale down when you resize the window
• overall, the left pane takes up valuable real estate if you scroll down.

I think this feature would make more sense as a dropdown menu.

[axispx]

@hanwen noted. I'll put in some changes soon.

[hanwen]

ping?

[axispx]

Hi, I got busy with work and completely forgot about this. I'll work on this tonight. Thanks for the reminder.

[hanwen]

sorry for the delay, i have been busy with other things

(sending through Gerrit as described in CONTRIBUTING usually yields faster feedback).

• if you click on a result in the -print version (the local viewer), you get the restrictions too, but they refer to the single file, and it doesn't make sense. I think the buttons should be disabled or simply not be there.

• the list of choices (repos, languages) looks alphabetical. I think ti should be ordered by frequency

• If there are no results, the dropdown becomes empty. Maybe remove or disable the button in those cases?

• if you edit the query, the dropdown potentially is invalid. Maybe not a big issue. Thoughts?

[hanwen]

implementation issue: you look at substrings ("lang:XXX") in the backend to populate the checkboxes.

This is incorrect if those bits appear as substrings eg.

clang:c

In the server, you can have access to the parsed query, so you should instead find the toplevel query.And and then look at its children to find all query.Repo/query.Language atoms.

[hanwen]

it also needs some work so the repo list view doesn't get messed up.

The drop down shouldn't be there for the repolist.

--- FAIL: TestBasic (0.00s)
e2e_test.go:230: query "/search?q=r:": result did not have "1234">master": template: navbar:33:37: executing "navbar" at <.FileMatches>: can't evaluate field FileMatches in type *web.RepoListInput
e2e_test.go:230: query "/search?q=r:": result did not have "Found 1 repositories": template: navbar:33:37: executing "navbar" at <.FileMatches>: can't evaluate field FileMatches in type *web.RepoListInput
e2e_test.go:230: query "/search?q=r:": result did not have "Feb 25, 2020 09:29": template: navbar:33:37: executing "navbar" at <.FileMatches>: can't evaluate field FileMatches in type *web.RepoListInput
e2e_test.go:230: query "/search?q=r:": result did not have "repo-url">name": template: navbar:33:37: executing "navbar" at <.FileMatches>: can't evaluate field FileMatches in type *web.RepoListInput
e2e_test.go:230: query "/search?q=r:": result did not have "1 files (36)": template: navbar:33:37: executing "navbar" at <.FileMatches>: can't evaluate field FileMatches in type *web.RepoListInput