Add "tip" version

[tianon]

This is pinned to the latest commit merged upstream before midnight (UTC) on Monday of the current week (#464 (comment), https://github.com/docker-library/faq#can-i-use-a-bot-to-make-my-image-update-prs).

Closes #464

(Includes/based on #530)

[tianon]

This change is technically valid even without this PR, but it's currently harmless (however with it in this PR, we end up with tags like tip-YYYYMMDD.0, which is undesirable).

[tianon]

It's technically very doable for us to implement Windows support, but this was enough that I didn't want to get too much deeper and decided to leave Windows as a TODO for now instead.

[tianon]

$ diff -u <(bashbrew cat golang) <(bashbrew cat <(./generate-stackbrew-library.sh))
--- /dev/fd/63	2024-08-15 16:35:29.584348497 -0700
+++ /dev/fd/62	2024-08-15 16:35:29.584348497 -0700
@@ -2,6 +2,27 @@
 GitRepo: https://github.com/docker-library/golang.git
 Builder: buildkit
 
+Tags: tip-20240810-bookworm, tip-bookworm
+SharedTags: tip-20240810, tip
+Architectures: amd64, arm32v5, arm32v7, arm64v8, i386, mips64le, ppc64le, s390x
+GitCommit: 819b7657d7783ea8b838ad2497af40f785119ccb
+Directory: tip/bookworm
+
+Tags: tip-20240810-bullseye, tip-bullseye
+Architectures: amd64, arm32v5, arm32v7, arm64v8, i386, mips64le, ppc64le, s390x
+GitCommit: 819b7657d7783ea8b838ad2497af40f785119ccb
+Directory: tip/bullseye
+
+Tags: tip-20240810-alpine3.20, tip-alpine3.20, tip-20240810-alpine, tip-alpine
+Architectures: amd64, arm32v6, arm32v7, arm64v8, i386, ppc64le, riscv64, s390x
+GitCommit: 819b7657d7783ea8b838ad2497af40f785119ccb
+Directory: tip/alpine3.20
+
+Tags: tip-20240810-alpine3.19, tip-alpine3.19
+Architectures: amd64, arm32v6, arm32v7, arm64v8, i386, ppc64le, s390x
+GitCommit: 819b7657d7783ea8b838ad2497af40f785119ccb
+Directory: tip/alpine3.19
+
 Tags: 1.23.0-bookworm, 1.23-bookworm, 1-bookworm, bookworm
 SharedTags: 1.23.0, 1.23, 1, latest
 Architectures: amd64, arm32v7, arm64v8, i386, mips64le, ppc64le, s390x

[tianon]

With that last push, this should be fully good for review / consideration now. 👀

[LaurentGoderre]

Is this expected?

[tianon]

Yeah, see https://github.com/docker-library/golang/pull/531/files#diff-75ae6e7f38ff53b3bddf05c7161672455ae64dfc0de8be7566925506498f8a78R205-R213 where I modified the calculation for supported -- the justification in my head at the time I wrote that is that setting this to false for src is more accurate since we don't build from source anywhere anymore, which didn't matter in practice until I added tip support again, where it also doesn't arguably matter either, but I left the field for completeness and decided to make the value more correct anyhow. 😄

[tianon]

Windows CI failures: docker-library/official-images#18435 (comment)

The problem is that the windows-2025 runner is too old to run the mcr.microsoft.com/windows/servercore:ltsc2025 image released this week (actions/runner-images#11582).

[yosifkit]

Seems fine.

[tianon]

Heh, oops. This:

golang/generate-stackbrew-library.sh

Lines 140 to 145 in 2a49384

	# cross-reference with supported architectures
	for arch in $variantArches; do
	if ! jq -e --arg arch "$arch" '.[env.version].arches[$arch].supported' versions.json &> /dev/null; then
	variantArches="$(sed <<<" $variantArches " -e "s/ $arch / /g")"
	fi
	done

Needs to take into account this:

golang/generate-stackbrew-library.sh

Lines 135 to 136 in 2a49384

	variantParent="$(awk 'toupper($1) == "FROM" { print $2 }' "$dir/Dockerfile" | sort -u)" # TODO this needs to handle multi-parents (we get lucky that they're the same)
	variantArches="${parentRepoToArches[$variantParent]}"

So that we also exclude the parent image's unsupported arches in the case of golang:tip.

[tianon]

(ie, the "we get lucky" bit there finally flipped to false 😂)