omzsh-plugin.md
markdown
| 1 | # Oh My ZSH Plugin — Reference |
| 2 | |
| 3 | Minimal, secure ZSH integration for Muse. Provides a prompt segment, core |
| 4 | aliases, and tab completion. Nothing runs automatically beyond what is needed to |
| 5 | keep the prompt accurate. |
| 6 | |
| 7 | --- |
| 8 | |
| 9 | ## Files |
| 10 | |
| 11 | | File | Purpose | |
| 12 | |------|---------| |
| 13 | | `tools/omzsh-plugin/muse.plugin.zsh` | Main plugin (~230 lines) | |
| 14 | | `tools/omzsh-plugin/_muse` | ZSH completion function | |
| 15 | | `tools/install-omzsh-plugin.sh` | Symlink installer | |
| 16 | |
| 17 | --- |
| 18 | |
| 19 | ## Prompt segment |
| 20 | |
| 21 | ```zsh |
| 22 | # In ~/.zshrc |
| 23 | PROMPT='%~ $(muse_prompt_info) %# ' |
| 24 | ``` |
| 25 | |
| 26 | `muse_prompt_info` emits nothing outside a Muse repo. Inside one it emits: |
| 27 | |
| 28 | ``` |
| 29 | %F{cyan}muse:(%F{<color>}<domain>:<branch>%F{cyan})%f |
| 30 | ``` |
| 31 | |
| 32 | The inner color is the only dirty signal — no extra symbol or count: |
| 33 | |
| 34 | - **magenta** — working tree is clean |
| 35 | - **yellow** — uncommitted changes exist |
| 36 | |
| 37 | This mirrors the Git plugin's `git:(branch)` format, extended with the domain |
| 38 | name — the key differentiator from a single-domain VCS. |
| 39 | |
| 40 | ### Examples |
| 41 | |
| 42 | | Output | Inner color | Meaning | |
| 43 | |--------|-------------|---------| |
| 44 | | `muse:(midi:main)` | magenta | clean | |
| 45 | | `muse:(midi:main)` | yellow | uncommitted changes | |
| 46 | | `muse:(midi:a1b2c3d4)` | magenta | detached HEAD, clean | |
| 47 | | `muse:(midi:a1b2c3d4)` | yellow | detached HEAD, uncommitted changes | |
| 48 | |
| 49 | The yellow state only appears after a `muse` command runs in the current shell. |
| 50 | |
| 51 | ### Domain icons (optional) |
| 52 | |
| 53 | Icons are off by default. Set `MUSE_PROMPT_ICONS=1` to prepend one: |
| 54 | |
| 55 | | Domain | Icon | Config key | |
| 56 | |--------|------|-----------| |
| 57 | | `midi` | `♪` | `MUSE_DOMAIN_ICONS[midi]` | |
| 58 | | `code` | `⌥` | `MUSE_DOMAIN_ICONS[code]` | |
| 59 | | `bitcoin` | `₿` | `MUSE_DOMAIN_ICONS[bitcoin]` | |
| 60 | | `scaffold` | `⬡` | `MUSE_DOMAIN_ICONS[scaffold]` | |
| 61 | | (unknown) | `◈` | `MUSE_DOMAIN_ICONS[_default]` | |
| 62 | |
| 63 | With icons on, the prompt becomes `♪ muse:(midi:main)`. |
| 64 | |
| 65 | --- |
| 66 | |
| 67 | ## Environment variables |
| 68 | |
| 69 | ### Configuration (set before `plugins=(… muse …)`) |
| 70 | |
| 71 | | Variable | Default | Meaning | |
| 72 | |----------|---------|---------| |
| 73 | | `MUSE_PROMPT_ICONS` | `0` | `1` prepends a domain icon before `muse:(…)` | |
| 74 | | `MUSE_DIRTY_TIMEOUT` | `1` | Seconds before dirty check aborts | |
| 75 | |
| 76 | ### State (read-only, exported by plugin) |
| 77 | |
| 78 | | Variable | Type | Meaning | |
| 79 | |----------|------|---------| |
| 80 | | `MUSE_REPO_ROOT` | string | Absolute path to repo root, or `""` | |
| 81 | | `MUSE_DOMAIN` | string | Active domain name | |
| 82 | | `MUSE_BRANCH` | string | Branch name, short SHA, or `?` | |
| 83 | | `MUSE_DIRTY` | integer | `1` if working tree has changes | |
| 84 | | `MUSE_DIRTY_COUNT` | integer | Number of changed paths | |
| 85 | |
| 86 | --- |
| 87 | |
| 88 | ## Hooks |
| 89 | |
| 90 | | Hook | When it fires | What it does | |
| 91 | |------|--------------|--------------| |
| 92 | | `chpwd` | On `cd` | Re-finds repo root, re-reads HEAD and domain; clears dirty state | |
| 93 | | `preexec` | Before any command | Sets `_MUSE_CMD_RAN=1` when command is `muse` | |
| 94 | | `precmd` | Before prompt | Runs full refresh (including dirty check) only if `_MUSE_CMD_RAN=1` | |
| 95 | |
| 96 | --- |
| 97 | |
| 98 | ## Aliases |
| 99 | |
| 100 | | Alias | Expands to | |
| 101 | |-------|-----------| |
| 102 | | `mst` | `muse status` | |
| 103 | | `msts` | `muse status --short` | |
| 104 | | `mcm` | `muse commit -m` | |
| 105 | | `mco` | `muse checkout` | |
| 106 | | `mlg` | `muse log` | |
| 107 | | `mlgo` | `muse log --oneline` | |
| 108 | | `mlgg` | `muse log --graph` | |
| 109 | | `mdf` | `muse diff` | |
| 110 | | `mdfst` | `muse diff --stat` | |
| 111 | | `mbr` | `muse branch` | |
| 112 | | `mtg` | `muse tag` | |
| 113 | | `mfh` | `muse fetch` | |
| 114 | | `mpull` | `muse pull` | |
| 115 | | `mpush` | `muse push` | |
| 116 | | `mrm` | `muse remote` | |
| 117 | |
| 118 | --- |
| 119 | |
| 120 | ## Completion |
| 121 | |
| 122 | The `_muse` completion function handles: |
| 123 | |
| 124 | - Top-level command names with descriptions. |
| 125 | - Branch names for `checkout`, `merge`, `cherry-pick`, `branch`, `reset`, `revert`, `diff`, `show`, `blame`. |
| 126 | - Remote names for `push`, `pull`, `fetch`. |
| 127 | - Tag names for `tag`. |
| 128 | - Config key suggestions for `config`. |
| 129 | - Subcommand names for `stash`, `remote`, `plumbing`, `commit` flags. |
| 130 | |
| 131 | All branch/tag/remote lookups use ZSH glob patterns against `.muse/refs/` and |
| 132 | `.muse/remotes/` — no subprocess, no `ls`, instant. |
| 133 | |
| 134 | --- |
| 135 | |
| 136 | ## Performance model |
| 137 | |
| 138 | | Trigger | Subprocesses | What runs | |
| 139 | |---------|-------------|-----------| |
| 140 | | Prompt render | 0 | Reads cached shell vars only | |
| 141 | | `cd` into repo | 1 (`python3`) | HEAD (ZSH read) + domain (python3) | |
| 142 | | `cd` outside repo | 0 | Clears vars only | |
| 143 | | After `muse` command | 1 (`muse status`) | Full refresh + dirty check | |
| 144 | | Tab completion | 0 | ZSH glob reads `.muse/refs/` | |
| 145 | |
| 146 | --- |
| 147 | |
| 148 | ## Security model |
| 149 | |
| 150 | ### Branch name injection |
| 151 | |
| 152 | `.muse/HEAD` is read with a pure ZSH `$(<file)` — no subprocess. Muse writes |
| 153 | HEAD in one of two self-describing forms (set by `muse/core/store.py`): |
| 154 | |
| 155 | ``` |
| 156 | ref: refs/heads/<branch> — on a branch |
| 157 | commit: <sha256> — detached HEAD |
| 158 | ``` |
| 159 | |
| 160 | The branch name is validated with `[[ "$branch" =~ '^[[:alnum:]/_.-]+$' ]]`. |
| 161 | Any name containing characters outside this set (including `%`, `$`, backticks, |
| 162 | quotes) is replaced with `?`. Valid names are additionally `%`-escaped |
| 163 | (`${branch//\%/%%}`) before insertion into the prompt string, so ZSH never |
| 164 | interprets them as prompt directives. |
| 165 | |
| 166 | ### Domain injection |
| 167 | |
| 168 | The domain value from `.muse/repo.json` is extracted by `python3` and validated |
| 169 | with `safe.isalnum() and 1 <= len(v) <= 32` before printing. The path to |
| 170 | `repo.json` is passed via the `MUSE_REPO_JSON` environment variable — never |
| 171 | interpolated into a `-c` string — so a path containing single quotes, spaces, |
| 172 | or special characters is handled safely. |
| 173 | |
| 174 | ### Path injection |
| 175 | |
| 176 | `cd -- "$MUSE_REPO_ROOT"` uses `--` so the path cannot be interpreted as a |
| 177 | flag. `timeout -- ...` follows the same pattern. |
| 178 | |
| 179 | ### No `eval` |
| 180 | |
| 181 | No user-supplied data is ever passed to `eval`. |
| 182 | |
| 183 | ### Completion safety |
| 184 | |
| 185 | The completion function uses ZSH glob expansion (`${refs_dir}/*(N:t)`) instead |
| 186 | of `$(ls ...)` to enumerate branches. This avoids word-splitting on filenames |
| 187 | that contain spaces, and prevents `ls` output from being treated as shell tokens. |
| 188 | |
| 189 | --- |
| 190 | |
| 191 | ## Installation |
| 192 | |
| 193 | ```bash |
| 194 | bash tools/install-omzsh-plugin.sh |
| 195 | ``` |
| 196 | |
| 197 | The script creates a symlink from `~/.oh-my-zsh/custom/plugins/muse/` to |
| 198 | `tools/omzsh-plugin/`. Because it is a symlink, pulling new commits to the Muse |
| 199 | repo automatically updates the plugin. |
| 200 | |
| 201 | Add to `~/.zshrc`: |
| 202 | |
| 203 | ```zsh |
| 204 | plugins=(git muse) |
| 205 | ``` |
| 206 | |
| 207 | Then add the prompt segment: |
| 208 | |
| 209 | ```zsh |
| 210 | # Append to your existing PROMPT, or set a new one: |
| 211 | PROMPT+='$(muse_prompt_info) ' |
| 212 | ``` |
| 213 | |
| 214 | Then reload: |
| 215 | |
| 216 | ```zsh |
| 217 | exec zsh |
| 218 | ``` |