Commit graph

8 commits

Author SHA1 Message Date
sterni
8d4b2f3d54 refactor(sterni): use pkgs over third_party to import from nixpkgs
This should ease migrating to a distinction between depot.third_party
and pkgs (as in nixpkgs) in the future.

Ref cl/2910, b/108.

Change-Id: I53a854071fddd7c0d0526cc4c5b16998202082c6
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2913
Tested-by: BuildkiteCI
Reviewed-by: tazjin <mail@tazj.in>
2021-04-10 11:40:18 +00:00
sterni
a5f2b446aa feat(sterni/nix/url): implement urldecoding
We use builtins.split directly as it should be a bit more efficient as
lib.splitStrings. Also its returning of a list for every regex match is
useful to update the state while parsing the tokens:

* The tokens are obtained by splitting the string at every '%'
* Everytime we see a boundary (that is a list in the returned
  list of builtins.split), we know that the first two chars of
  the next string are a percent encoded character.

One implementation flaw is that it will currently crash if it encounters
mal-formed URLs (since int.fromHex chrashes if it encounters any non
hex digit characters) and accepts some malformed urlencoding like
"foo %A".

Change-Id: I90d08d7a71b16b4f4a4879214abd7aeff46c20c8
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2744
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
2021-04-01 13:09:46 +00:00
sterni
b810c46a45 feat(users/sterni/nix/utf8): pure nix utf-8 decoder
users.sterni.nix.utf8 implements UTF-8 decoding in pure nix. We
implement the decoding as a simple state machine which is fed one byte
at a time. Decoding whole strings is possible by subsequently calling
step. This is done in decode which uses builtins.foldl' to get around
recursion restrictions and a neat trick using builtins.deepSeq puck
showed me limiting the size of the thunks in a foldl' (which can also
cause a stack overflow).

This makes decoding arbitrarily large UTF-8 files into codepoints using
nix theoretically possible, but it is not really practical: Decoding a
36KB LaTeX file I had lying around takes ~160s on my laptop.

Change-Id: Iab8c973dac89074ec280b4880a7408e0b3d19bc7
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2590
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
2021-03-05 11:07:41 +00:00
sterni
5ae1d3fd7b feat(users/sterni/nix/flow): add switch conditional
switch would probably otherwise be called match, but has been renamed so
it isn't confused with string.match and the enum matching capabilities
yants has.

It implements the closest to pattern matching nix can come which is
still flexible enough to not be painful: Syntactically it works like
cond, but is given a value. Instead of booleans it checks passed
predicates or equality if simple values are passed. Both types of checks
can be mixed.

Change-Id: I40f000979cfd469316e15fd58d6c3a80312c1cc4
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2589
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
2021-03-05 11:07:41 +00:00
sterni
ef40a8621f feat(users/sterni/nix/fun): make lrs read left to right completely
Change-Id: I57d290f770bc1d6bd88a46924889b919d68201e3
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2588
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
2021-03-05 11:07:41 +00:00
sterni
7af0fb1066 refactor(users/sterni/nix/string): don't calculate length for drop
Since nix ends the substring at the end of the string anyways we can
just statically use the largest nix integer as the length of the string.
According to my testing this it ever so slightly faster as well.

Change-Id: I64566e91c7b223f03dcebe3bc5710696dc4261bc
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2587
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
2021-03-05 11:07:41 +00:00
sterni
8ff14cacb6 feat(users/sterni/nix): move flow.match to string.match
After all it only matches strings.

Change-Id: I3d2e5221ef43f692de69028e78ed98b6b11f82d1
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2586
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
2021-03-05 11:07:41 +00:00
sterni
3b33c1bd76 feat(users/sterni/nix): add sternis nix lib
What you see here is mostly the fallout of me implementing a correct
urlencode implementation in nix for Profpatsch's blog implementation
(although they'll probably keep it at arm's length).

Where I want to go from here:

* Extend this library towards general purpose nix™, mainly by
  implementing missing interfaces which you'd still have to use
  <nixpkgs/lib> for right now. Reexposing parts of <nixpkgs/lib>
  with better naming is fine for now, at some point I'd contemplate
  making this depend on nothing outside of depot, maybe even itself
  (should be easy we only use yants for an easily replaceable check).

* Improve error messages possibly by carefully reintroducing yants. I
  originally typed essentially everything using yants, but turns out
  this can a) be dangerous when stuff you are handling throws because
  type checking means evaluating and b) has a incredible performance
  cost in some cases.

* Reexpose builtins with better naming and slightly wrapped so they
  don't unrecoverably throw in cases where a null or something would
  suffice.

Change-Id: I33ab08ca4e62dbc16b86c66c653935686e6b0e79
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2541
Reviewed-by: sterni <sternenseemann@systemli.org>
Reviewed-by: Profpatsch <mail@profpatsch.de>
Tested-by: BuildkiteCI
2021-03-01 17:34:35 +00:00