GitLab

The speed-up is smaller than I would like, only 1-2%.

Move few Arbitrary instances to more correct places,
add tests

Installing (copy or symlink) executable message prints destination.

Add Described to IndexState (incl. tests).

- Writing a regex to parse dates is awful.
- Add ShortText conversions to PackageName and UnqualComponentName
- Add mkDependency, which maintains the invariant
- Remove VersionRangeParens - it's not preserved by parsec . pretty
  roundtrip
- Move moree instances into Cabal-quickcheck,
  use the package in cabal-install tests

More checks in version range parser

Do this already in the Parsec instance parser.
This allows removing checks from `D.PD.Check`.
Later this would also allow removing non-relevant
constructors from `VersionRange`, allowing easier testing.

This change causes 10% slowdown: from

```
135768 files processed
  7350 files contained warnings
113156 files have check warnings
     0 files failed to parse

120.901201s elapsed
117.640431s elapsed
119.663620s elapsed
119.454329s elapsed
119.785214s elapsed
```

to

```
135768 files processed
 31912 files contained warnings
113109 files have check warnings
     0 files failed to parse

130.969593s elapsed
132.016403s elapsed
134.214536s elapsed
128.753382s elapsed
131.503804s elapsed
```

I hope the slowdown is acceptable, and I have an idea which may mitigate
this. I'll try out it after I done further refactorings.

Note how (parser) warnings grew by a factor. There are plenty of (old)
files on Hackage, which don't use correct cabal-version.  For that
reason we only issue warnings, and not fail.  Quirks approach won't
scale for these. In comparison, there are even more files
with check warnings

- remove parallel code, it's complicated and doesn't speedup reliably
- count files with warning
- add --keep-going
- add `clock` measurement from inside the parsec test

Add Quirk for single invalid UTF8 file.

Partially fixes https://github.com/haskell/cabal/issues/6587
For local files, there might be invalid UTF8; but if
file comes from Hackage, we can assume they are valid UTF8.

Remove MONOLITHIC build

Add RepoName newtype

Make it, LocalRepo, RemoteRepo, IndexState and Timestamp use
Pretty/Parsec instead of Text

Mostly adding `unRepoName` to error printing statements

Resolve #6369 and #6393: Allow cabal v2-install pkgname:exename or http://example.com/package.tar.gz(#sha256=abcde...)

We can write URIs with a fragment like

    https://hackage.haskell.org/package/cabal-fmt-0.1.2/cabal-fmt-0.1.2.tar.gz#sha256=aae556efbcaddfd65c6a1c1811b122b0d8c8d00624c8c2e36aabb5e9f9ea9840

and downloadURI will check the hash after download before continuing.
The hash check supersedes ETag

Rename OSX jobs, drop 8.8.2

Disable test for 3324 on Windows

The filesystem woes make it fail way too often

Drop Travis for master. Resolves #6500.

buildinfo-reference-generator

Add rewriteFileLBS and use it to write setup wrapper

Note all Described instances are implemented. This is just a start.

Adapt to simplified subsumption patch

Originally written by Ryan Scott in
https://github.com/haskell/cabal/pull/6545#issuecomment-592712318

Better checkout

Use GHC-8.8.3 + checkout@v2

docs: Reference default-extensions from ghc-options