picnoir/Nix
1
0
Fork 0
Code Issues Pull requests 1 Releases Wiki Activity

nix/why-depends: fix output of --precise

Browse source 
I haven't checked when this was exactly introduced, but on Nix 2.16 I
realized that the additional lines inserted when using `--precise` are
completely separated from the tree:

    nix why-depends /nix/store/ccgr4faaxys39s091qridxg1947lggh4-evcxr-0.14.2 /nix/store/b7hvml0m3qmqraz1022fwvyyg6fc1vdy-gcc-12.2.0 --precise --extra-experimental-features nix-command
    /nix/store/ccgr4faaxys39s091qridxg1947lggh4-evcxr-0.14.2
        → /nix/store/lcf37pgp3rgww67v9x2990hbfwx96c1w-gcc-wrapper-12.2.0
            → /nix/store/b7hvml0m3qmqraz1022fwvyyg6fc1vdy-gcc-12.2.0
    └───bin/evcxr: …':'}.PATH=${PATH/':''/nix/store/lcf37pgp3rgww67v9x2990hbfwx96c1w-gcc-wrapper-12.2.0/bin'':'/':'}…
        └───bin/cpp: …k disable=SC2193.[[ "/nix/store/b7hvml0m3qmqraz1022fwvyyg6fc1vdy-gcc-12.2.0/bin/cpp" = *++ ]] &&…

This is apparently because `std::cout` is buffered and flushed in the
end whereas the rest of the output isn't. The fix is rather simple, just
use `logger->cout` as it's already the case for the rest of the code.

This way we also don't need to insert additional newlines in the `hits`
map since that's something the logger takes care of.

Also added a small test to make sure that the layout of this is somehow
tested to reduce the risk of further regressions here.
This commit is contained in:
Maximilian Bosch 2023-08-04 23:11:08 +02:00
parent 635df5ee95
commit 7c09104a94
No known key found for this signature in database
GPG key ID: 9A6EEA275CA5BE0A
2 changed files with 10 additions and 5 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

10
src/nix/why-depends.cc
View file

@ -239,7 +239,7 @@ struct CmdWhyDepends : SourceExprCommand, MixOperateOnOptions
if (pos != std::string::npos) {
size_t margin = 32;
auto pos2 = pos >= margin ? pos - margin : 0;
hits[hash].emplace_back(fmt("%s: …%s…\n",
hits[hash].emplace_back(fmt("%s: …%s…",
p2,
hilite(filterPrintable(
std::string(contents, pos2, pos - pos2 + hash.size() + margin)),
@ -255,7 +255,7 @@ struct CmdWhyDepends : SourceExprCommand, MixOperateOnOptions
for (auto & hash : hashes) {
auto pos = target.find(hash);
if (pos != std::string::npos)
hits[hash].emplace_back(fmt("%s -> %s\n", p2,
hits[hash].emplace_back(fmt("%s -> %s", p2,
hilite(target, pos, StorePath::HashLen, getColour(hash))));
}
}
@ -272,9 +272,9 @@ struct CmdWhyDepends : SourceExprCommand, MixOperateOnOptions
for (auto & hit : hits[hash]) {
bool first = hit == *hits[hash].begin();
std::cout << tailPad
<< (first ? (last ? treeLast : treeConn) : (last ? treeNull : treeLine))
<< hit;
logger->cout("%s%s%s", tailPad,
(first ? (last ? treeLast : treeConn) : (last ? treeNull : treeLine)),
hit);
if (!all) break;
}

5
tests/why-depends.sh
View file

@ -22,3 +22,8 @@ echo "$PRECISE_WHY_DEPENDS_OUTPUT" | grepQuiet input-2
# But only the “precise” one should refer to `reference-to-input-2`
echo "$FAST_WHY_DEPENDS_OUTPUT" | grepQuietInverse reference-to-input-2
echo "$PRECISE_WHY_DEPENDS_OUTPUT" | grepQuiet reference-to-input-2
<<<"$PRECISE_WHY_DEPENDS_OUTPUT" sed -n '2p' | grepQuiet "└───reference-to-input-2 -> "
<<<"$PRECISE_WHY_DEPENDS_OUTPUT" sed -n '3p' | grep " →" | grepQuiet "dependencies-input-2"
<<<"$PRECISE_WHY_DEPENDS_OUTPUT" sed -n '4p' | grepQuiet " └───input0: …" # in input-2, file input0
<<<"$PRECISE_WHY_DEPENDS_OUTPUT" sed -n '5p' | grep " →" | grepQuiet "dependencies-input-0" # is dependencies-input-0 referenced