standalone-installer-unix: Use new aarch64 builds for macOS

Conditions on the Nextstrain CLI version being requested, as aarch64
builds will only be available going forward for new releases.  Assumes
the next release will be 8.2.0!

Disables Rosetta check when using an aarch64 build, as the checks will
be done at the runtime-level instead by `nextstrain setup` and
`nextstrain check-setup`.

.github/workflows/standalone-installers.yaml

@@ -39,6 +39,7 @@ jobs:
           - ubuntu-22.04
           - macos-11
           - macos-12
+          - macos-14      # (aarch64)
           - windows-2019
           - windows-2022
 

CHANGES.md

@@ -16,8 +16,13 @@ development source code and as such may not be routinely kept up to date.
 ## Improvements
 
 * We now produce standalone installation archives for macOS running on aarch64
-  hardware (aka arm64, Apple Silicon, M1/M2).
-  ([#357](https://github.com/nextstrain/cli/pull/357))
+  hardware (aka arm64, Apple Silicon, M1/M2).  The standalone installer will
+  use these archives starting with this release.  Rosetta 2 is still required
+  by our Conda runtime (and recommended for our Docker runtime), but checks
+  that it's enabled are now performed during runtime setup instead of at
+  installation.
+  ([#357](https://github.com/nextstrain/cli/pull/357),
+  [#358](https://github.com/nextstrain/cli/pull/358))
 
 * The Conda and Docker runtime checks performed by `nextstrain setup` and
   `nextstrain check-setup` now test if Rosetta 2 is enabled for macOS on

bin/standalone-installer-unix

@@ -20,17 +20,17 @@ shopt -s failglob
 # Globals declared here to make them more obvious, but set by main() to avoid
 # source ordering requirements and delay execution until the full file is
 # parsed.
-declare KERNEL TARGET DESTINATION VERSION
+declare VERSION KERNEL TARGET DESTINATION
 
 # Wrap everything in a function which we call at the end to avoid execution of
 # a partially-downloaded program.
 main() {
+    VERSION="${1:-${VERSION:-latest}}"
+
     KERNEL="${KERNEL:-$(uname -s)}"
     TARGET="${TARGET:-$(target-triple)}"
     DESTINATION="${DESTINATION:-${NEXTSTRAIN_HOME:-$HOME/.nextstrain}/cli-standalone}"
 
-    VERSION="${1:-${VERSION:-latest}}"
-
     local archive archive_url tmp
 
     archive="standalone-${TARGET}.tar.gz"
@@ -115,9 +115,23 @@ target-triple() {
             ;;
 
         Darwin)
-            [[ "$machine" == x86_64 || "$machine" == arm64 ]] || die "unsupported architecture: $machine"
-            [[ "$machine" != arm64 ]] || pgrep -qU _oahd 2>/dev/null || die "Rosetta 2 not enabled.  Please run:"$'\n\n'"    softwareupdate --install-rosetta"$'\n\n'"and then retry this installation of Nextstrain CLI."
-            machine=x86_64
+            # Rosetta 2 will not be needed for the standalone version of
+            # Nextstrain CLI itself as of 8.2.0.  The Conda runtime still
+            # requires it and the Docker runtime can benefit from it, but we
+            # now check for it in their setup instead.
+            #  -trs, 1 Feb 2024
+               version-gte 8.2.0 \
+            || [[ "$machine" != arm64 ]] \
+            || pgrep -qU _oahd 2>/dev/null \
+            || die "Rosetta 2 not enabled.  Please run:"$'\n\n'"    softwareupdate --install-rosetta"$'\n\n'"and then retry this installation of Nextstrain CLI."
+
+            # aarch64 builds will only be available starting with 8.2.0.  Older
+            # versions only provide x86_64, which will run under Rosetta.
+            case "$machine" in
+                x86_64) ;;
+                arm64) version-gte 8.2.0 && machine=aarch64 || machine=x86_64;;
+                *) die "unsupported architecture: $machine";;
+            esac
             vendor=apple
             os=darwin
             ;;
@@ -129,6 +143,16 @@ target-triple() {
     echo "$machine-$vendor-$os"
 }
 
+version-gte() {
+    local minimum="$1"
+
+    # If $minimum sorts before $VERSION, then $VERSION is at least ≥$minimum.
+    # Note that non-numeric values sort by byte order, so "latest" and
+    # "pr-build/123" and so on end up after (greater than) a numeric value like
+    # 8.1.0.  Both macOS/BSD sort and GNU sort support -V.
+    [[ $(printf '%s\n%s\n' "$minimum" "$VERSION" | sort -V | head -n1) == "$minimum" ]]
+}
+
 default-shell() {
     local shell