diff --git a/public/checksum.txt b/public/checksum.txt
index 2735178..43774b1 100644
--- a/public/checksum.txt
+++ b/public/checksum.txt
@@ -1,4 +1,4 @@
 6de66efba021ebcf462e7672577d9f6876f13db55691f04e7009ff7e78d658b8 public/sh/install_zpmod.sh
-6e753a0314ba9f2e4f0a2c429798ca3767af4fb94c669e6923d161d6af7aa745 public/sh/install.sh
+eff43da44827d4774eed21d31d841df04b9cd8fe089c1b59d38bef3608920754 public/sh/install.sh
 08cc893ceb982fc99d17db1966c6c30790cc571e16e4f5392352d995f5252952 public/sh/sync-init.sh
 c979e39748d1d86ace17a61ff2b1bf6e1224a43291c25bf7fad985d1e9e11af1 public/zsh/init.zsh
diff --git a/public/sh/install.sh b/public/sh/install.sh
index 6edb7d9..9d740da 100755
--- a/public/sh/install.sh
+++ b/public/sh/install.sh
@@ -40,11 +40,11 @@ shift $((OPTIND - 1))
 # | is the sed delimiter used in the substitution; \ and & are special in
 # sed replacement expressions. The *[\\]* pattern matches a single backslash.
 case "${BOPT}" in
-  # [\\] is a bracket expression for a literal backslash.
-  *'|'* | *[\\]* | *'&'* )
-    printf '%s\n' "-- ERROR -- Invalid -b value: branch name must not contain '|', '\\', or '&'." >&2
-    exit 1
-    ;;
+# [\\] is a bracket expression for a literal backslash.
+*'|'* | *[\\]* | *'&'*)
+  printf '%s\n' "-- ERROR -- Invalid -b value: branch name must not contain '|', '\\', or '&'." >&2
+  exit 1
+  ;;
 esac
 
 SCRIPT_DIR=""
@@ -104,8 +104,8 @@ fetch_to_file() {
 
 is_absolute_path() {
   case "${1-}" in
-    /*) return 0 ;;
-    *) return 1 ;;
+  /*) return 0 ;;
+  *) return 1 ;;
   esac
 }
 
@@ -183,6 +183,13 @@ if ! command -v git >/dev/null 2>&1; then
   exit 1
 fi
 
+# -b is used as a fetch refspec and inside generated Zsh: accept only a
+# well-formed branch name (no ':', no leading '-', no '..').
+if ! command git check-ref-format --branch "${BOPT}" >/dev/null 2>&1; then
+  printf '%s\n' "-- ERROR -- Invalid -b value: '${BOPT}' is not a valid branch name." >&2
+  exit 1
+fi
+
 # Get the download-progress bar tool
 command mkdir -p /tmp/zi
 cd /tmp/zi || exit 1
@@ -204,9 +211,10 @@ if test -d "${ZI_HOME}/${ZI_BIN_DIR_NAME}/.git"; then
   if test -f "${ZI_HOME}/${ZI_BIN_DIR_NAME}/zi.zsh"; then
     # Canonical zi remote URLs (HTTPS and SSH, with and without .git suffix)
     case "$(command git -C "${ZI_HOME}/${ZI_BIN_DIR_NAME}" remote get-url origin 2>/dev/null || true)" in
-      https://github.com/z-shell/zi | https://github.com/z-shell/zi.git \
-      | git@github.com:z-shell/zi | git@github.com:z-shell/zi.git)
-        _zi_valid=1 ;;
+    https://github.com/z-shell/zi | https://github.com/z-shell/zi.git | \
+      git@github.com:z-shell/zi | git@github.com:z-shell/zi.git)
+      _zi_valid=1
+      ;;
     esac
   fi
   if [ "${_zi_valid}" -ne 1 ]; then
@@ -216,9 +224,18 @@ if test -d "${ZI_HOME}/${ZI_BIN_DIR_NAME}/.git"; then
   fi
   cd "${ZI_HOME}/${ZI_BIN_DIR_NAME}" || exit 1
   printf '%s\n' "▓▒░ Updating (z-shell/zi) plugin manager at ${ZI_HOME}/${ZI_BIN_DIR_NAME}"
-  command git clean -d -f -f
-  command git reset --hard HEAD
-  command git pull -q origin "${BOPT}"
+  # Match `zi self-update`: fetch the requested branch and fast-forward only.
+  # Local state is never discarded; refuse loudly when it cannot be advanced.
+  if ! command git fetch -q origin "refs/heads/${BOPT}"; then
+    printf '%s\n' "-- ERROR -- failed to fetch origin ${BOPT} into ${ZI_HOME}/${ZI_BIN_DIR_NAME}" >&2
+    exit 1
+  fi
+  if ! command git merge -q --ff-only FETCH_HEAD; then
+    printf '%s\n' "-- ERROR -- ${ZI_HOME}/${ZI_BIN_DIR_NAME} cannot be fast-forwarded to origin/${BOPT}; local state was left untouched:" >&2
+    command git status --short --branch 2>/dev/null | head -20 >&2
+    printf '%s\n' "-- ERROR -- resolve the checkout state shown above so HEAD can fast-forward to origin/${BOPT} (move local commits to another branch, or drop changes you do not need), then rerun the installer." >&2
+    exit 1
+  fi
 else
   cd "${ZI_HOME}" || exit 1
   printf '%s\n' "▓▒░ Installing (z-shell/zi) plugin manager at ${ZI_HOME}/${ZI_BIN_DIR_NAME}"
@@ -238,22 +255,32 @@ fi
 
 MAIN_PROFILE() {
   THE_ZDOTDIR="${ZDOTDIR:-${HOME}}"
-  if grep -E '(zi|init|zinit)\.zsh' "${THE_ZDOTDIR}/.zshrc" >/dev/null 2>&1; then
-    printf '%s\n' "▓▒░ Seems that .zshrc already has content or setup skipped - no changes will be made."
-    ZOPT='skip'
+  ZSHRC_INTEGRATED=0
+  # Detect an existing Zi integration by a real source line. A comment that
+  # merely mentions the file name must not suppress the integration.
+  if grep -E '^[[:space:]]*(source|\.)[[:space:]]+[^#]*(zi|init|zinit)\.zsh(["'"'"'[:space:]]|$)' "${THE_ZDOTDIR}/.zshrc" >/dev/null 2>&1; then
+    printf '%s\n' "▓▒░ Seems that .zshrc already sources Zi - the integration block will not be added."
+    ZSHRC_INTEGRATED=1
   fi
-  if [ "${ZOPT}" != skip ] && [ "${AOPT}" != loader ]; then
+  # The .zshrc text refers to the home through $HOME; the installer itself
+  # keeps using the real path.
+  # shellcheck disable=SC2016
+  case "${ZI_HOME}" in
+  "${HOME}") ZI_HOME_TEXT='$HOME' ;;
+  "${HOME}"/*) ZI_HOME_TEXT="\$HOME${ZI_HOME#"${HOME}"}" ;;
+  *) ZI_HOME_TEXT="${ZI_HOME}" ;;
+  esac
+  if [ "${ZOPT}" != skip ] && [ "${ZSHRC_INTEGRATED}" -eq 0 ] && [ "${AOPT}" != loader ]; then
     printf '%s\n' "▓▒░ Updating ${THE_ZDOTDIR}/.zshrc"
-    ZI_HOME="$(echo "${ZI_HOME}" | sed "s|${HOME}|\$HOME|")"
     command cat <<-EOF >>"${THE_ZDOTDIR}/.zshrc"
-if [[ ! -f ${ZI_HOME}/${ZI_BIN_DIR_NAME}/zi.zsh ]]; then
+if [[ ! -f ${ZI_HOME_TEXT}/${ZI_BIN_DIR_NAME}/zi.zsh ]]; then
   print -P "%F{33}▓▒░ %F{160}Installing (%F{33}z-shell/zi%F{160})…%f"
-  command mkdir -p "${ZI_HOME}" && command chmod go-rwX "${ZI_HOME}"
-  command git clone -q --filter=blob:none --single-branch --branch "${BOPT}" https://github.com/z-shell/zi "${ZI_HOME}/${ZI_BIN_DIR_NAME}" && \\
+  command mkdir -p "${ZI_HOME_TEXT}" && command chmod go-rwX "${ZI_HOME_TEXT}"
+  command git clone -q --filter=blob:none --single-branch --branch "${BOPT}" https://github.com/z-shell/zi "${ZI_HOME_TEXT}/${ZI_BIN_DIR_NAME}" && \\
     print -P "%F{33}▓▒░ %F{34}Installation successful.%f%b" || \\
     print -P "%F{160}▓▒░ The clone has failed.%f%b"
 fi
-source "${ZI_HOME}/${ZI_BIN_DIR_NAME}/zi.zsh"
+source "${ZI_HOME_TEXT}/${ZI_BIN_DIR_NAME}/zi.zsh"
 autoload -Uz _zi
 (( \${+_comps} )) && _comps[zi]=_zi
 # examples here -> https://wiki.zshell.dev/ecosystem/category/-annexes
@@ -261,7 +288,7 @@ zicompinit # <- https://wiki.zshell.dev/docs/guides/commands
 EOF
     printf '%s\n' "▓▒░ Minimal configuration"
   fi
-  if [ "${AOPT}" = loader ] && [ "${ZOPT}" != skip ]; then
+  if [ "${AOPT}" = loader ] && [ "${ZOPT}" != skip ] && [ "${ZSHRC_INTEGRATED}" -eq 0 ]; then
     command cat <<-EOF >>"${THE_ZDOTDIR}/.zshrc"
 if [[ -n \${XDG_CONFIG_HOME:-} && \${XDG_CONFIG_HOME} == /* ]]; then
   ZI_LOADER_CONFIG_HOME="\${XDG_CONFIG_HOME}/zi"
@@ -278,9 +305,22 @@ EOF
 }
 
 ANNEX_PROFILE() {
+  if [ "${AOPT}" != annex ] && [ "${AOPT}" != zunit ]; then
+    printf '%s\n' "▓▒░ Skipped all annexes"
+    return 0
+  fi
+  if [ "${ZOPT}" = skip ]; then
+    printf '%s\n' "▓▒░ .zshrc changes were skipped (-i skip); annexes were not configured"
+    return 0
+  fi
+  # Rerunning the installer must not append the block a second time.
+  if grep -E '^[^#]*z-shell/z-a-meta-plugins([[:space:]]|$)' "${THE_ZDOTDIR}/.zshrc" >/dev/null 2>&1; then
+    printf '%s\n' "▓▒░ .zshrc already loads z-shell/z-a-meta-plugins - annex block not added again"
+    return 0
+  fi
+  file="${WORKDIR}/temp-zsh-config"
   if [ "${AOPT}" = annex ]; then
-    file="${WORKDIR}/temp-zsh-config"
-    command cat <<-EOF >>"${file}"
+    command cat <<-EOF >"${file}"
 zi light-mode for \\
   z-shell/z-a-meta-plugins \\
   @annexes # <- https://wiki.zshell.dev/ecosystem/category/-annexes
@@ -288,21 +328,29 @@ zi light-mode for \\
 zicompinit # <- https://wiki.zshell.dev/docs/guides/commands
 EOF
     printf '%s\n' "▓▒░ Installing annexes"
-    command cat "${file}" >>"${THE_ZDOTDIR}/.zshrc"
-    zsh -ic "@zi-scheduler burst"
-  elif [ "${AOPT}" = zunit ]; then
-    file2="${WORKDIR}/temp-zunit-config"
-    command cat <<-EOF >>"${file2}"
+  else
+    command cat <<-EOF >"${file}"
 zi light-mode for \\
   z-shell/z-a-meta-plugins \\
   @annexes @zunit
 EOF
     printf '%s\n' "▓▒░ Installing annexes + zunit"
-    command cat "${file2}" >>"${THE_ZDOTDIR}/.zshrc"
-    zsh -ic "@zi-scheduler burst"
-  else
-    printf '%s\n' "▓▒░ Skipped all annexes"
   fi
+  command cat "${file}" >>"${THE_ZDOTDIR}/.zshrc"
+  ANNEX_BURST "${file}"
+}
+
+ANNEX_BURST() {
+  # Install the annexes now without an interactive shell and with -f, so no
+  # user startup file (not even .zshenv) runs: source only zi.zsh and the
+  # fragment just written. A failure here must not abort an install whose
+  # .zshrc changes are already in place.
+  if zsh -f -c 'builtin source "$1" && builtin source "$2" && @zi-scheduler burst' zsh \
+    "${ZI_HOME}/${ZI_BIN_DIR_NAME}/zi.zsh" "$1"; then
+    return 0
+  fi
+  printf '%s\n' "▓▒░ Annexes could not be installed now; they will be installed on the next shell start." >&2
+  return 0
 }
 
 ZPMOD_PROFILE() {
diff --git a/tests/installers.sh b/tests/installers.sh
index e8955d2..b1ee218 100755
--- a/tests/installers.sh
+++ b/tests/installers.sh
@@ -400,6 +400,7 @@ if [ "${1:-}" = "-C" ]; then
 fi
 
 cmd="${1:-}"
+[ -z "${ZI_SRC_TEST_GIT_LOG:-}" ] || printf '%s\n' "$*" >>"${ZI_SRC_TEST_GIT_LOG}"
 [ "$#" -gt 0 ] && shift
 
 case "${cmd}" in
@@ -413,7 +414,24 @@ case "${cmd}" in
     printf '%s\n' '# fake zi.zsh' > "${dest}/zi.zsh"
     printf '%s\n' '# fake _zi completion' > "${dest}/lib/_zi"
     ;;
-  clean | reset | pull)
+  check-ref-format)
+    [ "${1:-}" = "--branch" ] || { printf '%s\n' "installers.sh git test double: expected --branch" >&2; exit 65; }
+    case "${2:-}" in
+      "" | -* | *:* | *..* | *[[:space:]]* | *~* | *^* | *\\* ) exit 1 ;;
+    esac
+    printf '%s\n' "$2"
+    ;;
+  fetch)
+    ;;
+  merge)
+    if [ "${ZI_SRC_TEST_FAKE_FF_FAIL:-0}" -ne 0 ]; then
+      printf '%s\n' "fatal: Not possible to fast-forward, aborting." >&2
+      exit 128
+    fi
+    ;;
+  status)
+    printf '%s\n' "## main...origin/main [ahead 1]"
+    printf '%s\n' " M zi.zsh"
     ;;
   log)
     printf '%s\n' 'abcdef0 - fake zi commit (now) <test>'
@@ -438,7 +456,25 @@ case "${cmd}" in
 esac
 EOF
 
-  command chmod a+x "${FAKE_BIN}/curl" "${FAKE_BIN}/git"
+  cat >"${FAKE_BIN}/zsh" <<'EOF'
+#!/usr/bin/env sh
+set -eu
+
+# The installer must never start an interactive shell: that would execute the
+# user's own startup files with the installer's environment.
+for arg; do
+  case "${arg}" in
+    -i | -i?* | -?*i?*)
+      printf '%s\n' "zsh test double: interactive flag ${arg}" >&2
+      exit 66
+      ;;
+  esac
+  [ "${arg}" != "-c" ] || break
+done
+[ -z "${ZI_SRC_TEST_ZSH_LOG:-}" ] || printf '%s\n' "zsh $*" >>"${ZI_SRC_TEST_ZSH_LOG}"
+EOF
+
+  command chmod a+x "${FAKE_BIN}/curl" "${FAKE_BIN}/git" "${FAKE_BIN}/zsh"
 }
 
 test_loader_install() {
@@ -639,6 +675,194 @@ test_update_rejects_wrong_remote() {
   pass "update path rejects a repository with a non-zi remote origin"
 }
 
+test_update_fast_forwards_without_reset() {
+  home="${TMP_ROOT}/update-ff-home"
+  data="${TMP_ROOT}/update-ff-data"
+  zi_bin="${data}/zi/bin"
+  git_log="${TMP_ROOT}/update-ff-git-log"
+  command mkdir -p "${home}" "${zi_bin}/.git"
+  printf '%s\n' '# fake zi.zsh' >"${zi_bin}/zi.zsh"
+
+  HOME="${home}" \
+    ZDOTDIR="${home}" \
+    XDG_DATA_HOME="${data}" \
+    ZI_SRC_TEST_ROOT="${ROOT}" \
+    ZI_SRC_TEST_GIT_LOG="${git_log}" \
+    PATH="${FAKE_BIN}:${PATH}" \
+    sh "${ROOT}/public/sh/install.sh" -i skip -b feature/test >/dev/null
+
+  contains "${git_log}" 'fetch -q origin refs/heads/feature/test'
+  contains "${git_log}" 'merge -q --ff-only FETCH_HEAD'
+  if grep -E '^(clean|reset|pull)( |$)' "${git_log}" >/dev/null 2>&1; then
+    fail "update path still discards local state (clean, reset, or pull was invoked)"
+  fi
+  pass "update path fetches and fast-forwards without discarding local state"
+}
+
+test_update_refuses_non_fast_forward() {
+  home="${TMP_ROOT}/update-nonff-home"
+  data="${TMP_ROOT}/update-nonff-data"
+  zi_bin="${data}/zi/bin"
+  err="${TMP_ROOT}/update-nonff-err"
+  command mkdir -p "${home}" "${zi_bin}/.git"
+  printf '%s\n' '# fake zi.zsh' >"${zi_bin}/zi.zsh"
+
+  set +e
+  HOME="${home}" \
+    ZDOTDIR="${home}" \
+    XDG_DATA_HOME="${data}" \
+    ZI_SRC_TEST_ROOT="${ROOT}" \
+    ZI_SRC_TEST_FAKE_FF_FAIL=1 \
+    PATH="${FAKE_BIN}:${PATH}" \
+    sh "${ROOT}/public/sh/install.sh" -i skip >/dev/null 2>"${err}"
+  exit_code="$?"
+  set -e
+
+  [ "${exit_code}" -ne 0 ] || fail "install.sh should have refused a non-fast-forward update"
+  contains "${err}" 'cannot be fast-forwarded'
+  contains "${err}" 'local state was left untouched'
+  contains "${err}" ' M zi.zsh'
+  pass "update path refuses a non-fast-forward and shows the checkout state"
+}
+
+test_zshrc_comment_does_not_suppress_integration() {
+  home="${TMP_ROOT}/probe-home"
+  data="${TMP_ROOT}/probe-data"
+  command mkdir -p "${home}"
+  printf '%s\n' '# Zi is loaded from ~/.config/zi/init.zsh, see the wiki' >"${home}/.zshrc"
+
+  HOME="${home}" \
+    ZDOTDIR="${home}" \
+    XDG_DATA_HOME="${data}" \
+    ZI_SRC_TEST_ROOT="${ROOT}" \
+    PATH="${FAKE_BIN}:${PATH}" \
+    sh "${ROOT}/public/sh/install.sh" >/dev/null
+
+  contains "${home}/.zshrc" "source \"${data}/zi/bin/zi.zsh\""
+  pass "a comment mentioning init.zsh does not suppress the .zshrc integration"
+
+  # A real source line is still detected and nothing is appended.
+  home2="${TMP_ROOT}/probe-home-sourced"
+  data2="${TMP_ROOT}/probe-data-sourced"
+  command mkdir -p "${home2}"
+  # shellcheck disable=SC2016
+  printf '%s\n' 'source "$HOME/.zi/bin/zi.zsh"' >"${home2}/.zshrc"
+  before="$(sha256_file "${home2}/.zshrc")"
+
+  HOME="${home2}" \
+    ZDOTDIR="${home2}" \
+    XDG_DATA_HOME="${data2}" \
+    ZI_SRC_TEST_ROOT="${ROOT}" \
+    PATH="${FAKE_BIN}:${PATH}" \
+    sh "${ROOT}/public/sh/install.sh" >/dev/null
+
+  [ "$(sha256_file "${home2}/.zshrc")" = "${before}" ] || fail "an existing source line did not suppress the integration block"
+  pass "an existing Zi source line keeps .zshrc unchanged"
+}
+
+test_annex_rerun_is_idempotent() {
+  home="${TMP_ROOT}/annex-home"
+  data="${TMP_ROOT}/annex-data"
+  zsh_log="${TMP_ROOT}/annex-zsh-log"
+  command mkdir -p "${home}"
+
+  for run in first second; do
+    HOME="${home}" \
+      ZDOTDIR="${home}" \
+      XDG_DATA_HOME="${data}" \
+      ZI_SRC_TEST_ROOT="${ROOT}" \
+      ZI_SRC_TEST_ZSH_LOG="${zsh_log}" \
+      PATH="${FAKE_BIN}:${PATH}" \
+      sh "${ROOT}/public/sh/install.sh" -a annex >/dev/null || fail "annex install (${run} run) failed"
+  done
+
+  meta_lines="$(grep -c 'z-shell/z-a-meta-plugins' "${home}/.zshrc")"
+  [ "${meta_lines}" -eq 1 ] || fail "annex block appended ${meta_lines} times across two runs"
+  contains "${home}/.zshrc" "source \"${data}/zi/bin/zi.zsh\""
+  # The burst ran once, non-interactively, sourcing only zi.zsh and the fragment.
+  burst_lines="$(wc -l <"${zsh_log}" | tr -d ' ')"
+  [ "${burst_lines}" -eq 1 ] || fail "expected one annex burst, saw ${burst_lines}"
+  contains "${zsh_log}" '@zi-scheduler burst'
+  # Logged with argv0 so the pattern cannot be read as grep options.
+  contains "${zsh_log}" 'zsh -f -c '
+  contains "${zsh_log}" "${data}/zi/bin/zi.zsh"
+  contains "${zsh_log}" 'temp-zsh-config'
+  pass "annex profile is idempotent across reruns and never starts an interactive shell"
+}
+
+test_skip_leaves_annex_out() {
+  home="${TMP_ROOT}/annex-skip-home"
+  data="${TMP_ROOT}/annex-skip-data"
+  zsh_log="${TMP_ROOT}/annex-skip-zsh-log"
+  command mkdir -p "${home}"
+
+  HOME="${home}" \
+    ZDOTDIR="${home}" \
+    XDG_DATA_HOME="${data}" \
+    ZI_SRC_TEST_ROOT="${ROOT}" \
+    ZI_SRC_TEST_ZSH_LOG="${zsh_log}" \
+    PATH="${FAKE_BIN}:${PATH}" \
+    sh "${ROOT}/public/sh/install.sh" -i skip -a annex >/dev/null
+
+  [ ! -e "${home}/.zshrc" ] || fail "-i skip -a annex modified .zshrc"
+  [ ! -e "${zsh_log}" ] || fail "-i skip -a annex still ran the annex burst"
+  pass "-i skip leaves .zshrc untouched even with an annex profile"
+}
+
+test_branch_option_rejects_refspec() {
+  home="${TMP_ROOT}/branch-refspec-home"
+  data="${TMP_ROOT}/branch-refspec-data"
+  err="${TMP_ROOT}/branch-refspec-err"
+  command mkdir -p "${home}"
+
+  set +e
+  HOME="${home}" \
+    ZDOTDIR="${home}" \
+    XDG_DATA_HOME="${data}" \
+    ZI_SRC_TEST_ROOT="${ROOT}" \
+    PATH="${FAKE_BIN}:${PATH}" \
+    sh "${ROOT}/public/sh/install.sh" -i skip -b 'main:refs/heads/other' >/dev/null 2>"${err}"
+  exit_code="$?"
+  set -e
+
+  [ "${exit_code}" -ne 0 ] || fail "install.sh accepted a refspec as -b"
+  contains "${err}" 'not a valid branch name'
+  [ ! -e "${data}/zi/bin/zi.zsh" ] || fail "install proceeded after an invalid -b value"
+  pass "-b rejects values that are not a branch name"
+}
+
+test_zshrc_text_uses_home_variable() {
+  home="${TMP_ROOT}/home-text home"
+  sibling="${TMP_ROOT}/home-text home-sibling"
+  command mkdir -p "${home}"
+
+  HOME="${home}" \
+    ZDOTDIR="${home}" \
+    XDG_DATA_HOME="${home}/xdg data" \
+    ZI_SRC_TEST_ROOT="${ROOT}" \
+    PATH="${FAKE_BIN}:${PATH}" \
+    sh "${ROOT}/public/sh/install.sh" >/dev/null
+
+  # shellcheck disable=SC2016
+  contains "${home}/.zshrc" 'source "$HOME/xdg data/zi/bin/zi.zsh"'
+  pass '.zshrc refers to a home under $HOME through the variable'
+
+  home2="${TMP_ROOT}/home-text-2"
+  command mkdir -p "${home2}"
+  HOME="${home2}" \
+    ZDOTDIR="${home2}" \
+    ZI_HOME="${sibling}" \
+    ZI_SRC_TEST_ROOT="${ROOT}" \
+    PATH="${FAKE_BIN}:${PATH}" \
+    sh "${ROOT}/public/sh/install.sh" >/dev/null
+
+  contains "${home2}/.zshrc" "source \"${sibling}/bin/zi.zsh\""
+  if grep -F '$HOME' "${home2}/.zshrc" >/dev/null 2>&1; then
+    fail 'a sibling of $HOME was rewritten as if it were inside it'
+  fi
+  pass '.zshrc keeps a literal path for a home that only shares a prefix with $HOME'
+}
+
 test_sync_init() {
   local_file="${TMP_ROOT}/local-init.zsh"
   remote_file="${TMP_ROOT}/remote-init.zsh"
@@ -693,4 +917,11 @@ test_standalone_zpmod_delegation
 test_update_valid_zi_clone
 test_update_rejects_foreign_repo
 test_update_rejects_wrong_remote
+test_update_fast_forwards_without_reset
+test_update_refuses_non_fast_forward
+test_zshrc_comment_does_not_suppress_integration
+test_annex_rerun_is_idempotent
+test_skip_leaves_annex_out
+test_branch_option_rejects_refspec
+test_zshrc_text_uses_home_variable
 test_sync_init