latest-allowed installs absolute latest (beta), not honoring required version

[dalmadebreceni]

Scans terraform files for required version, finds it. Then ignores it, switches to "version=latest" instead of latest of required (major) version.
tfenv/libexec/tfenv-install latest-allowed ->

[...]
+ version_requested=latest-allowed
+ [[ -n latest-allowed ]]
+ log debug 'Version Requested: latest-allowed'
+ '[' debug '!=' debug ']'
+ [[ latest-allowed =~ ^v.*$ ]]
+ [[ latest-allowed =~ ^min-required$ ]]
+ [[ latest-allowed =~ ^latest-allowed$ ]]
+ log debug 'Detecting latest allowable version...'
[...]
++ grep -h required_version [...]
+ version_spec='~> 1.2'
++ echo '~> 1.2'
++ sed -E 's/[^0-9.]+//'
+ version_num=1.2
+ log debug 'Using 1.2 from version spec: ~> 1.2'
+ '[' debug '!=' debug ']'
+ case "${version_spec}" in
++ echo 1.2
++ rev
++ cut -d. -f2-
++ rev
+ version_without_rightmost=1
+ version_requested='latest:^1'
+ log debug 'Determined the requested version to be: latest:^1'
+ '[' debug '!=' debug ']'
+ [[ latest:^1 =~ ^latest:.*$ ]]
+ version=latest
+ regex='^1'
+ log debug 'Version uses latest keyword with regex: ^1'
+ '[' debug '!=' debug ']'
+ echo 'latest:^1'
Terraform v1.4.0-alpha20221207 is already installed

[dalmadebreceni]

this fails because it cuts the version to 1, so works only if the terraform version is in the form of having 2 dots (aka 1.2.), but not with 1 dot (1.2).

[sspans-sbp]

Would it be an option to introduce latest-allowed-alpha and have that tag include pre-release versions?
That would make latest-allowed and latest:^1. a lot more useful for most normal users.

Now I'm jumping through hoops to make tfenv not install alpha versions.

[Michenux]

tfenv latest-allowed should align with terraform behaviour, in the documentation : "A prerelease version can be selected only by an exact version constraint (the = operator or no operator). Prerelease versions do not match inexact operators such as >=, ~>, etc."

[Zordrak]

Root Cause Analysis (from code review)

The issue is in libexec/tfenv-resolve-version in the ~> handling logic. For ~> 1.2:

version_without_rightmost="$(echo "${version_num}" | rev | cut -d. -f2- | rev)"
version_requested="latest:^${version_without_rightmost}"

With input ~> 1.2:

• version_num = 1.2
• After rev | cut -d. -f2- | rev: version_without_rightmost = 1
• Result: version_requested = latest:^1

The regex ^1 matches ANY version starting with 1, including 1.4.0-alpha20221207. The ~> operator in Terraform means "pessimistic constraint" — ~> 1.2 should mean >= 1.2.0, < 2.0.0 but should exclude pre-release versions.

Two issues:

1. The regex ^1 is too broad — it needs a dot anchor: ^1\. to avoid matching e.g. 10.x in future
2. Pre-release versions (alpha, beta, rc) are not filtered out, so latest:^1 picks up 1.4.0-alpha20221207 if it is the first match

Fix: The regex should be ^1\. AND the version list should be filtered to exclude pre-release versions (alpha/beta/rc) unless explicitly requested.