fix(installer): RAID validation, set -e fix, drop dead shadow branch

Two installer cleanups from the todo backlog.

validate_config now rejects a RAID_LEVEL the selected disk count can't support, guarding the unattended path (the interactive path already constrains the choice). While adding it I found a latent bug: the error loop's ((errors++)) returned 0 on the first error and tripped set -e in the monolith's `[[ UNATTENDED == true ]] && validate_config` call, aborting after one warning instead of listing every problem. Switched to pre-increment so the count accumulates as designed. Added four bats cases, including one that runs validate_config under set -e outside bats' run shield.

build.sh dropped the dead shadow-file rebuild else-branch. The profile is always copied fresh from releng (which ships /etc/shadow), so the branch never ran, and its hardcoded account list had drifted from what releng provides. Replaced with an assertion that fails the build loudly if the file is ever missing.

1 files changed, 58 insertions, 0 deletions

diff --git a/tests/unit/test_config.bats b/tests/unit/test_config.bats
index af23e4a..4169c5e 100644
--- a/tests/unit/test_config.bats
+++ b/tests/unit/test_config.bats
@@ -5,6 +5,8 @@ setup() {
     # shellcheck disable=SC1091
     source "${BATS_TEST_DIRNAME}/../../installer/lib/common.sh"
     # shellcheck disable=SC1091
+    source "${BATS_TEST_DIRNAME}/../../installer/lib/raid.sh"
+    # shellcheck disable=SC1091
     source "${BATS_TEST_DIRNAME}/../../installer/lib/config.sh"
 }
 
@@ -93,6 +95,62 @@ EOF
     [[ "$output" == *"4 error"* ]]
 }
 
+@test "validate_config under set -e reports every error, not just the first" {
+    # Reproduces the monolith's call structure: `set -e` is active and
+    # validate_config is invoked as the final command of an && list. A
+    # post-increment that returns the pre-increment value (0 on the first
+    # error) trips set -e and aborts the function after one warning. This
+    # test runs outside bats' `run` shield (which sets +e) so the real
+    # accumulate-and-report behavior is exercised.
+    run bash -c '
+        set -e
+        source "'"${BATS_TEST_DIRNAME}"'/../../installer/lib/common.sh"
+        source "'"${BATS_TEST_DIRNAME}"'/../../installer/lib/raid.sh"
+        source "'"${BATS_TEST_DIRNAME}"'/../../installer/lib/config.sh"
+        HOSTNAME=""; TIMEZONE=""; SELECTED_DISKS=(); ROOT_PASSWORD=""
+        UNATTENDED=true
+        [[ "$UNATTENDED" == true ]] && validate_config
+    '
+    [ "$status" -eq 1 ]
+    [[ "$output" == *"HOSTNAME not set"* ]]
+    [[ "$output" == *"TIMEZONE not set"* ]]
+    [[ "$output" == *"No disks selected"* ]]
+    [[ "$output" == *"ROOT_PASSWORD not set"* ]]
+    [[ "$output" == *"4 error"* ]]
+}
+
+@test "validate_config rejects a RAID_LEVEL invalid for the disk count" {
+    HOSTNAME=h
+    TIMEZONE=UTC
+    ROOT_PASSWORD=x
+    SELECTED_DISKS=(/dev/sda /dev/sdb)
+    RAID_LEVEL=raidz1
+    run validate_config
+    [ "$status" -eq 1 ]
+    [[ "$output" == *"Invalid RAID_LEVEL"* ]]
+    [[ "$output" == *"raidz1"* ]]
+}
+
+@test "validate_config accepts a RAID_LEVEL valid for the disk count" {
+    HOSTNAME=h
+    TIMEZONE=UTC
+    ROOT_PASSWORD=x
+    SELECTED_DISKS=(/dev/sda /dev/sdb /dev/sdc)
+    RAID_LEVEL=raidz1
+    run validate_config
+    [[ "$output" != *"Invalid RAID_LEVEL"* ]]
+}
+
+@test "validate_config accepts an empty RAID_LEVEL for a single disk" {
+    HOSTNAME=h
+    TIMEZONE=UTC
+    ROOT_PASSWORD=x
+    SELECTED_DISKS=(/dev/sda)
+    RAID_LEVEL=""
+    run validate_config
+    [[ "$output" != *"Invalid RAID_LEVEL"* ]]
+}
+
 @test "validate_config rejects an invalid timezone" {
     HOSTNAME="h"
     TIMEZONE="Not/A_Real_Zone_xyz"