Support pyenv version-name --force

libexec/pyenv-version-name

@@ -1,8 +1,25 @@
 #!/usr/bin/env bash
 # Summary: Show the current Python version
+#
+#   -f/--force    If a version doesn't exist, print it as is rather than produce an error
+
 set -e
 [ -n "$PYENV_DEBUG" ] && set -x
 
+while [[ $# -gt 0 ]]
+do
+    case "$1" in
+        -f|--force)
+            FORCE=1
+            shift
+            ;;
+        *)
+            break
+            ;;
+    esac
+done
+
+
 if [ -z "$PYENV_VERSION" ]; then
   PYENV_VERSION_FILE="$(pyenv-version-file)"
   PYENV_VERSION="$(pyenv-version-file-read "$PYENV_VERSION_FILE" || true)"
@@ -33,16 +50,20 @@ OLDIFS="$IFS"
     # Remove the explicit 'python-' prefix from versions like 'python-3.12'.
     normalised_version="${version#python-}"
     if version_exists "${version}" || [ "$version" = "system" ]; then
-      versions=("${versions[@]}" "${version}")
+      versions+=("${version}")
     elif version_exists "${normalised_version}"; then
-      versions=("${versions[@]}" "${normalised_version}")
+      versions+=("${normalised_version}")
     elif resolved_version="$(pyenv-latest -b "${version}")"; then
-      versions=("${versions[@]}" "${resolved_version}")
+      versions+=("${resolved_version}")
     elif resolved_version="$(pyenv-latest -b "${normalised_version}")"; then
-      versions=("${versions[@]}" "${resolved_version}")
+      versions+=("${resolved_version}")
     else
-      echo "pyenv: version \`$version' is not installed (set by $(pyenv-version-origin))" >&2
-      any_not_installed=1
+      if [[ -n $FORCE ]]; then
+        versions+=("${normalised_version}")
+      else
+        echo "pyenv: version \`$version' is not installed (set by $(pyenv-version-origin))" >&2
+        any_not_installed=1
+      fi
     fi
   done
 }

test/version-name.bats

@@ -73,6 +73,11 @@ SH
   assert_failure "pyenv: version \`1.2' is not installed (set by PYENV_VERSION environment variable)"
 }
 
+@test "missing version with --force" {
+  PYENV_VERSION=1.2 run pyenv-version-name -f
+  assert_success "1.2"
+}
+
 @test "one missing version (second missing)" {
   create_version "3.5.1"
   PYENV_VERSION="3.5.1:1.2" run pyenv-version-name