enhance(scripts/lint-packages.sh): optimize handling of version arrays

[TomJo2000]

CC: @Biswa96
This PR will prevent failure modes such as the one in https://github.com/termux/termux-packages/actions/runs/19025073645 by skipping the version checks past version validation for version arrays on all but index 0, since that is the git diff, version compare, and sequential revision increase/proper revision reset checks only need to be run once.

I'd like to additionally request @truboxl for review regarding the recent on-device issues with the linter.
This branch doesn't contain fixes for on-device usage in its initial state, however I plan to add these later today after concluding on-device testing of the linter.

[robertkirkman]

using termux-apt on-device, I can't reproduce the exact error that truboxl saw invalid regular expression, maybe truboxl can explain how to reproduce that, but I can report the first error I have encountered testing lint-packages.sh on-device, which is this:

================================================================

Package: cabal-install

Layout: PASS
Package name 'cabal-install': PASS
End of line check: PASS
File permission check: PASS
Indentation check: FAILED
packages/cabal-install/build.sh:29:			 ghc-options: -fexternal-interpreter -pgmi=$(command -v termux-ghc-iserv)
packages/cabal-install/build.sh:36:			 flags: +no-cmm
Mixed indentation

================================================================

A problem has been found in 'packages/cabal-install/build.sh'.
Checked 0 packages before the first error was detected.

================================================================

which is reproducible by the command scripts/lint-packages.sh packages/cabal-install/build.sh in termux-apt, but is not reproducible inside the termux-package-builder, so there must be some difference between how they each evaluate packages/cabal-install/build.sh.

[TomJo2000]

Is your on-device clone of the repo up to date?
Because the current linter version passes all packages on my PC, but I am seeing that mixed indentation so what's going on with that.

[robertkirkman]

Is your on-device clone of the repo up to date?

yes.

Because the current linter version passes all packages on my PC, but I am seeing that mixed indentation so what's going on with that.

It appears that for some reason, lint-packages.sh can detect the mixed indentation of cabal-install when run on-device, but cannot detect it when run inside termux-package-builder. I am not sure what the root cause of that would be.

termux-packages/packages/cabal-install/build.sh

Lines 27 to 30 in e8a9bb6

	cat <<-EOF >>cabal.project.local
	package *
	ghc-options: -fexternal-interpreter -pgmi=$(command -v termux-ghc-iserv)
	EOF

[TomJo2000]

It's probably regex related.
Ugh, that's a pain in the ass but I need to debug that anyway.

[TomJo2000]

Actually it's a sequencing error.
Because both of these mixed indentation lines are in a heredoc, the heredoc logic hits continue before the mixed indentation check is ever run on the line.

termux-packages/scripts/lint-packages.sh

Lines 84 to 95 in e8a9bb6

	# make sure it's a heredoc, not a herestring
	if [[ "$line" != *'<<<'* ]]; then
	# Skip this check in entirely within heredocs
	[[ "$line" =~ $heredoc_regex ]] && {
	heredoc_terminator="${BASH_REMATCH[1]}"
	}
	[[ -n ${heredoc_terminator} && "$line" == [[:space:]]*"${heredoc_terminator//[\'\"]}" ]] && {
	heredoc_terminator=''
	}
	(( ${#heredoc_terminator} )) && continue
	fi

So we just need to move this block up above the heredoc check.

termux-packages/scripts/lint-packages.sh

Lines 97 to 101 in e8a9bb6

	# check for mixed indentation
	[[ "$line" =~ ^($'\t'+ +| +$'\t'+) ]] && {
	issues[0]='Mixed indentation'
	bad_lines[i]="${pkg_script}:${i}:$line"
	}

[TomJo2000]

Judging from the comment on the heredoc block, this was intentional behavior, however it seems to be unintended as far as expectations are concerned.