Use `set -u` and `set -o pipefail` to catch accidental mistakes and
failures more strongly.
- `set -u` catches the use of undefined variables
- `set -o pipefail` catches failures (like `set -e`) earlier in the
pipeline.
This makes the tests a bit more robust. It is nice to read code not
worrying about these spurious success paths (via uncaught) errors
undermining the tests. Indeed, I caught some bugs doing this.
There are a few tests where we run a command that should fail, and then
search its output to make sure the failure message is one that we
expect. Before, since the `grep` was the last command in the pipeline
the exit code of those failing programs was silently ignored. Now with
`set -o pipefail` it won't be, and we have to do something so the
expected failure doesn't accidentally fail the test.
To do that we use `expect` and a new `expectStderr` to check for the
exact failing exit code. See the comments on each for why.
`grep -q` is replaced with `grepQuiet`, see the comments on that
function for why.
`grep -v` when we just want the exit code is replaced with `grepInverse,
see the comments on that function for why.
`grep -q -v` together is, surprise surprise, replaced with
`grepQuietInverse`, which is both combined.
Co-authored-by: Robert Hensing <roberth@users.noreply.github.com>
This makes the position object used in exceptions abstract, with a
method getSource() to get the source code of the file in which the
error originated. This is needed for lazy trees because source files
don't necessarily exist in the filesystem, and we don't want to make
libutil depend on the InputAccessor type in libfetcher.
With this patch, and this file I called `log.py`:
#!/usr/bin/env nix-shell
#!nix-shell -i python3 -p python3 --pure
import sys
from pprint import pprint
stack = []
timestack = []
for line in open(sys.argv[1]):
components = line.strip().split(" ", 2)
if components[0] != "function-trace":
continue
direction = components[1]
components = components[2].rsplit(" ", 2)
loc = components[0]
_at = components[1]
time = int(components[2])
if direction == "entered":
stack.append(loc)
timestack.append(time)
elif direction == "exited":
dur = time - timestack.pop()
vst = ";".join(stack)
print(f"{vst} {dur}")
stack.pop()
and:
nix-instantiate --trace-function-calls -vvvv ../nixpkgs/pkgs/top-level/release.nix -A unstable > log.matthewbauer 2>&1
./log.py ./log.matthewbauer > log.matthewbauer.folded
flamegraph.pl --title matthewbauer-post-pr log.matthewbauer.folded > log.matthewbauer.folded.svg
I can make flame graphs like: http://gsc.io/log.matthewbauer.folded.svg
---
Includes test cases around function call failures and tryEval. Uses
RAII so the finish is always called at the end of the function.
