fix invalid escape sequences in easyconfigs by using raw strings (r"...")

[Flamefire]

Similar to #11148 this handles the invalid escape sequences by using raw strings for all ECs

I.e. it fixes the <string>:25: DeprecationWarning: invalid escape sequence \$ warnings when parsing an EC and the related flake8 warning

This is clean with flake8 --select W605 --filename '*.eb' -j5 now

• Requires fix postinstallcmds in shovill easyconfigs #17279

[lexming]

I think that this change will cause issues with quote_str(), which can escape backslashes. Raw strings will end up having double backslashes.

[Flamefire]

If that is the case maybe the function needs a fix? I'm not sure how it is used though so can't tell if it causes problems
If so then better use escaped backslash

[Flamefire]

Quick ping here. Still getting those DeprecationWarnings and I think we should fix those before they become errors. And the problem just get worse as more and more ECs get added by copying those "mistakes"

[Flamefire]

Rebased again. What is the status here @boegel ?

[jfgrimm]

As decided in issue #16330, we have deprecated the use of True to signify a system-toolchain dependency (#16384), in favour of the more intuitive SYSTEM template constant. Due to the change in the test suite, please run eb --sync-pr-with-develop 11149 and update the PR to use SYSTEM instead.

[Flamefire]

@jfgrimm I'm not sure your comment applies here as this is only a refactoring to fix the style/warnings not changing or introducing anything

Anyway can this and #11148 be reviewed and merged please so we can enable flake8 on CI and avoid reintroducing the issues I already fixed?

I just rebased this, resolved the conflict and checked that flake8 --select W605 --filename '*.eb' -j5 doesn't return anything

[Flamefire]

I extracted the shovill changes into a separate PR and added a CI check to avoid reintroducing this. That can be extended once the other flake8-related PRs have been merged.

[lexming]

Test report by @lexming
SUCCESS
Build succeeded for 58 out of 58 (58 easyconfigs in total)
node300.hydra.os - Linux CentOS Linux 7.9.2009, x86_64, Intel(R) Xeon(R) Gold 6148 CPU @ 2.40GHz, Python 3.6.8
See https://gist.github.com/lexming/203867d0566011912c771172b4ebea10 for a full test report.
note: only a single easyconfig per package tested and only on recent toolchains

[lexming]

LGTM

[lexming]

Going in, thanks @Flamefire !

[lexming]

Tests rolled-back to normal state in #17304