Fix non-bash output while detecting shell (#2561)

Co-authored-by: Ivan Pozdeev <vano@mail.mipt.ru>

libexec/pyenv-init

@@ -83,7 +83,7 @@ function main() {
     exit 0
     ;;
   "detect-shell")
-    detect_profile
+    detect_profile 1
     print_detect_shell
     exit 0
     ;;
@@ -93,6 +93,8 @@ function main() {
 }
 
 function detect_profile() {
+  local detect_for_detect_shell="$1"
+
   case "$shell" in
   bash )
     if [ -e '~/.bash_profile' ]; then
@@ -112,8 +114,13 @@ function detect_profile() {
     rc='~/.profile'
     ;;
   * )
-    profile='your shell'\''s login startup file'
-    rc='your shell'\''s interactive startup file'
+    if [ -n "$detect_for_detect_shell" ]; then
+      profile=
+      rc=
+    else
+      profile='your shell'\''s login startup file'
+      rc='your shell'\''s interactive startup file'
+    fi
     ;;
   esac
 }

test/init.bats

@@ -63,6 +63,12 @@ OUT
   assert_line 'pyenv init - | source'
 }
 
+@test "shell detection for installer" {
+  run pyenv-init --detect-shell
+  assert_success
+  assert_line "PYENV_SHELL_DETECT=bash"
+}
+
 @test "option to skip rehash" {
   run pyenv-init - --no-rehash
   assert_success