feat(prompt): load the starship prompt

AGENTS.md

@@ -14,9 +14,10 @@ Personal Zsh configuration repository: shell environment, dotfiles, aliases, fun
 1. `~/.zshrc` sources `load.zsh` (added by `install.sh`)
 2. `load.zsh` orchestrates everything:
    - Locale, zsh options, `path-ethic` plugin (synchronous — needed at startup)
-   - Sources all `include/` files: exports, mise, aliases, functions, keybindings, completions, history
+   - Sources all `include/` files: exports, mise, aliases, functions, keybindings, completions, history, prompt
    - **`include/mise` runs synchronously right after `include/exports`** — runtime `PATH` must be correct at the first prompt, so never defer it
    - **fzf shell integration loads at the end of `include/keybindings`**, before `fzf-tab` — `fzf-tab` must be the last plugin to bind `^I`
+   - **`include/prompt` runs synchronously after `include/history`** so the first prompt is Starship's; it is skipped when `starship` is not on `PATH` or `TERM` is `dumb`. Starship's `PROMPT` is a `$(…)` expansion, so `setopt prompt_subst` in `load.zsh` is required
    - **Deferred plugins** (via `zsh-defer`, interactive sessions only): `zsh-history-substring-search`, `zsh-autosuggestions`, `fzf-tab`, `zsh-syntax-highlighting` — these load after the prompt appears
    - **Non-interactive fallback**: deferred plugins load synchronously when `[[ ! -o interactive ]]` (e.g., tests)
    - **`zsh-syntax-highlighting` MUST be loaded LAST** (after all other plugins and keybindings, even when deferred)
@@ -31,7 +32,7 @@ Personal Zsh configuration repository: shell environment, dotfiles, aliases, fun
 - **`dotfiles/`** — Symlinked to `$HOME` during install (not copied — changes are live). The repo has no `.gitignore` of its own — ignore rules go in `dotfiles/.gitignore_global`
 - **`agents/`** — Global Agent instructions (`AGENTS.md`). `install.sh` symlinks agent configuration files (e.g. `~/.claude/CLAUDE.md`, `~/.codex/AGENTS.md`) to this file. If a target already exists, the script prompts `[n/Y]` before replacing it (default Yes, also at end of input); an existing correct link is left untouched
 - **`brew/Brewfile`** — The only Brewfile: every Homebrew package of the three machine profiles (`essentials`, `dev`, `workstation`), one line each, each inside its `if profiles.include?("<name>")` block. The profiles come from `HOMEBREW_PROFILE_INSTALL_PROFILES` (unset or empty means every profile, so that a plain `brew bundle cleanup` never treats a profile's packages as unlisted; `profile install` always sets it; the profiles form one chain in the order of `known`, so applying `dev` also applies `essentials`, and applying `workstation` also applies `dev` and `essentials`); the `HOMEBREW_` prefix is required because the `brew` wrapper passes no other variables to the Brewfile. `include/exports` exports `HOMEBREW_BUNDLE_FILE` with this file's path, so a plain `brew bundle` reads it from any directory; `scripts/profile` still passes `--file` on every `brew bundle` call, so it does not depend on the shell environment. Keep the file to Ruby logic that Homebrew documents for Brewfiles (no processes, no loading of other files). No language runtimes here — mise owns them
-- **`config/`** — Config files with nested targets (`install.sh` links dotfiles by basename only, so they cannot live in `dotfiles/`). `config/mise/profile.toml` holds the runtime versions and mise settings; `install.sh` links it to `~/.config/mise/conf.d/profile.toml` (not `config.toml`, which `mise use -g` writes to). `config/nvim/` is the nvim config (`init.lua` and the committed `lazy-lock.json`); `install.sh` links the directory as a whole to `~/.config/nvim`, so lazy.nvim writes the lockfile into the repo, and moves an old-layout `~/.config/nvim` (a directory whose `init.lua` links into the repo) to `~/.config/nvim.bak.<epoch seconds>` first
+- **`config/`** — Config files with nested targets (`install.sh` links dotfiles by basename only, so they cannot live in `dotfiles/`). `config/mise/profile.toml` holds the runtime versions and mise settings; `install.sh` links it to `~/.config/mise/conf.d/profile.toml` (not `config.toml`, which `mise use -g` writes to). `config/starship.toml` is the Starship prompt config; `include/exports` points `STARSHIP_CONFIG` at it, so it needs no link. `config/nvim/` is the nvim config (`init.lua` and the committed `lazy-lock.json`); `install.sh` links the directory as a whole to `~/.config/nvim`, so lazy.nvim writes the lockfile into the repo, and moves an old-layout `~/.config/nvim` (a directory whose `init.lua` links into the repo) to `~/.config/nvim.bak.<epoch seconds>` first
 - **`bootstrap.sh`** — One-command new-Mac setup (`curl … | zsh -s -- [essentials|dev|workstation]`): Homebrew, clone, `install.sh`, then `scripts/profile install`. At the repo root, not in `scripts/`, so it is not a command on `PATH`. Add no install logic here; it belongs in `scripts/profile` or `install.sh`
 - **`zsh-plugins/`** — Git submodules
 - **`tests/`** — Test suite using `zsh-scriptest` submodule
@@ -71,7 +72,7 @@ Tests use the `zsh-scriptest` framework (submodule in `tests/`). Test files must
 - Test functions are called sequentially at the bottom of the file (not auto-discovered).
 - Test files must be executable — the runner silently skips a non-executable file.
 - Call `cleanup` before `finish_tests`: `finish_tests` exits on failure, and a skipped cleanup leaves the fingerprint behind for the next file.
-- Run child shells with `env -i HOME="$HOME" PATH=… TERM=dumb` so variables exported by the developer's own shell cannot mask what `load.zsh` exports.
+- Run child shells with `env -i HOME="$HOME" PATH=… TERM=dumb` so variables exported by the developer's own shell cannot mask what `load.zsh` exports. Only a test of `include/prompt` sets another `TERM`, because the prompt is skipped on a dumb terminal.
 - See `tests/sanity.test.sh` for the canonical pattern.
 
 CI runs on **ubuntu-latest** and **macos-latest** (GitHub Actions, `.github/workflows/ci.yml`).

config/starship.toml

@@ -0,0 +1,69 @@
+"$schema" = 'https://starship.rs/config-schema.json'
+
+# Each git module after the branch starts with its own space, so the group ends with one space only in a repo.
+format = """
+$username$hostname$directory\
+($git_branch$git_commit$git_state${custom.git_files}$git_metrics$git_status )\
+$all"""
+
+palette = 'git'
+
+[palettes.git]
+branch = '#b8c084'
+muted = '#8b98a0'
+added = '#8fa83c'
+deleted = '#d9473f'
+
+[aws]
+disabled = true
+
+[gcloud]
+disabled = true
+
+[git_branch]
+symbol = ' '
+style = 'fg:branch'
+format = '[$symbol$branch(:$remote_branch)]($style)'
+
+[git_commit]
+style = 'fg:branch'
+format = '[ \($hash$tag\)]($style)'
+
+[git_state]
+style = 'fg:yellow'
+format = '[ \($state( $progress_current/$progress_total)\)]($style)'
+
+# Starship has no variable for the total number of changed files.
+# --ignore-submodules=dirty skips the scan of every submodule's working tree, which
+# can push the module past command_timeout; a moved submodule commit still counts.
+[custom.git_files]
+description = 'Number of changed files, staged, unstaged or untracked'
+when = true
+require_repo = true
+shell = ['sh']
+command = 'n=$(git status --porcelain --ignore-submodules=dirty | wc -l | tr -d " "); [ "$n" -eq 0 ] || echo "$n"'
+style = 'fg:muted'
+format = '([ ± $output]($style))'
+
+# Untracked files count in ± N but add no lines here: git_metrics diffs tracked files against HEAD.
+[git_metrics]
+disabled = false
+ignore_submodules = true
+format = '( [•](fg:muted)( [+$added](fg:added))( [-$deleted](fg:deleted)))'
+
+# File counts come from custom.git_files; the stash, conflict and remote state left here needs no submodule scan.
+[git_status]
+ignore_submodules = true
+format = '($all_status$ahead_behind)'
+conflicted = '[ =${count}](bold fg:red)'
+stashed = '[ ≡${count}](fg:purple)'
+deleted = ''
+renamed = ''
+modified = ''
+staged = ''
+typechanged = ''
+untracked = ''
+ahead = '[ ⇡${count}](fg:added)'
+behind = '[ ⇣${count}](fg:deleted)'
+diverged = '[ ⇡${ahead_count}⇣${behind_count}](bold fg:yellow)'
+up_to_date = ''

include/exports

@@ -16,6 +16,9 @@ PATH="$PATH:$HOME/go/bin"
 # Homebrew: a plain `brew bundle` reads the repo Brewfile from any directory.
 export HOMEBREW_BUNDLE_FILE="$SHA1N_PROFILE_HOME/brew/Brewfile"
 
+# Starship reads the repo config directly, so no ~/.config/starship.toml link is needed.
+export STARSHIP_CONFIG="$SHA1N_PROFILE_HOME/config/starship.toml"
+
 # Backup
 export BACKUP_DST_PATH="/Volumes/Backup/latest"
 export BACKUP_SRC_PATH="/Volumes/Content"

include/prompt

@@ -0,0 +1,9 @@
+#!/usr/bin/env zsh
+
+# Starship errors on a dumb terminal at init and at every prompt, which no stderr redirect here can cover.
+if (( $+commands[starship] )) && [[ $TERM != dumb ]]; then
+  () {
+    local starship_init
+    starship_init="$(starship init zsh 2>/dev/null)" && eval "$starship_init"
+  }
+fi

load.zsh

@@ -30,6 +30,7 @@ source $SHA1N_PROFILE_HOME/include/functions
 source $SHA1N_PROFILE_HOME/include/keybindings
 source $SHA1N_PROFILE_HOME/include/completions
 source $SHA1N_PROFILE_HOME/include/history
+source $SHA1N_PROFILE_HOME/include/prompt
 
 # fzf-tab: after compinit (include/completions), before zsh-syntax-highlighting
 if [[ -o interactive ]]; then

tests/env.test.sh

@@ -19,21 +19,33 @@ load_and_eval() {
 }
 
 eval_load_eval() {
-  local search_path="$1" before="$2" after="$3"
-  env -i HOME="$HOME" PATH="$search_path" TERM=dumb \
+  local search_path="$1" before="$2" after="$3" term="${4:-dumb}"
+  env -i HOME="$HOME" PATH="$search_path" TERM="$term" \
     "$zsh_bin" -f -c 'eval "$2"; source "$1"; eval "$3"' _ "$load_script" "$before" "$after"
 }
 
 load_stderr() {
-  local search_path="$1"
-  env -i HOME="$HOME" PATH="$search_path" TERM=dumb \
+  local search_path="$1" term="${2:-dumb}"
+  env -i HOME="$HOME" PATH="$search_path" TERM="$term" \
     "$zsh_bin" -f -c 'source "$1" 2>&1 >/dev/null' _ "$load_script"
 }
 
 new_stub_dir() {
   mktemp -d "${TMPDIR:-/tmp}/env_test_stubs.XXXXXX"
 }
 
+write_starship_stub() {
+  local stub_dir="$1" init_status="$2"
+  cat >"$stub_dir/starship" <<EOF
+#!/bin/sh
+if [ "\$1" = "init" ] && [ "\$2" = "zsh" ]; then
+  [ $init_status -eq 0 ] || exit $init_status
+  echo "PROMPT='starship-stub> '"
+fi
+EOF
+  chmod +x "$stub_dir/starship"
+}
+
 function test_pip_require_virtualenv() {
   test_case_title
 
@@ -56,6 +68,17 @@ function test_homebrew_bundle_file() {
   assert_equal "$profiles_type" ""
 }
 
+function test_starship_config() {
+  test_case_title
+
+  local exported="$(load_and_eval "$system_path" 'print -r -- "${(t)STARSHIP_CONFIG}"')"
+  local value="$(load_and_eval "$system_path" 'print -r -- "$STARSHIP_CONFIG"')"
+
+  assert_equal "$value" "$profile_home/config/starship.toml"
+  assert_contains "$exported" "export"
+  assert_file_exists "$value"
+}
+
 function test_go_bin_on_path() {
   test_case_title
 
@@ -115,7 +138,7 @@ EOF
   assert_empty "$err"
 }
 
-function test_prompt_not_set() {
+function test_prompt_not_set_without_starship() {
   test_case_title
 
   local before="PROMPT='sentinel> '; RPROMPT='right-sentinel'"
@@ -129,6 +152,47 @@ function test_prompt_not_set() {
   assert_equal "$rprompt" "right-sentinel"
 }
 
+function test_starship_init_sets_prompt() {
+  test_case_title
+
+  local stub_dir="$(new_stub_dir)"
+  write_starship_stub "$stub_dir" 0
+
+  local prompt="$(eval_load_eval "$stub_dir:$system_path" "PROMPT='sentinel> '" 'print -r -- "$PROMPT"' xterm-256color)"
+
+  rm -rf "$stub_dir"
+
+  assert_equal "$prompt" "starship-stub> "
+}
+
+function test_starship_skipped_on_dumb_terminal() {
+  test_case_title
+
+  local stub_dir="$(new_stub_dir)"
+  write_starship_stub "$stub_dir" 0
+
+  local prompt="$(eval_load_eval "$stub_dir:$system_path" "PROMPT='sentinel> '" 'print -r -- "$PROMPT"' dumb)"
+
+  rm -rf "$stub_dir"
+
+  assert_equal "$prompt" "sentinel> "
+}
+
+function test_starship_init_failure_is_silent() {
+  test_case_title
+
+  local stub_dir="$(new_stub_dir)"
+  write_starship_stub "$stub_dir" 1
+
+  local prompt="$(eval_load_eval "$stub_dir:$system_path" "PROMPT='sentinel> '" 'print -r -- "$PROMPT"' xterm-256color)"
+  local err="$(load_stderr "$stub_dir:$system_path" xterm-256color)"
+
+  rm -rf "$stub_dir"
+
+  assert_equal "$prompt" "sentinel> "
+  assert_empty "$err"
+}
+
 function test_no_theme_functions() {
   test_case_title
 
@@ -140,11 +204,15 @@ function test_no_theme_functions() {
 setup
 run_test test_pip_require_virtualenv
 run_test test_homebrew_bundle_file
+run_test test_starship_config
 run_test test_go_bin_on_path
 run_test test_mise_activated
 run_test test_mise_absent_is_silent
 run_test test_fzf_without_zsh_flag_is_silent
-run_test test_prompt_not_set
+run_test test_prompt_not_set_without_starship
+run_test test_starship_init_sets_prompt
+run_test test_starship_skipped_on_dumb_terminal
+run_test test_starship_init_failure_is_silent
 run_test test_no_theme_functions
 cleanup
 finish_tests