fix(system): remove brew cli proxying

docs/cli/index.md

@@ -166,9 +166,6 @@ Can also use `MISE_NO_HOOKS=1`
 - [`mise sync python [--pyenv] [--uv]`](/cli/sync/python.md)
 - [`mise sync ruby [--brew]`](/cli/sync/ruby.md)
 - [`mise system <SUBCOMMAND>`](/cli/system.md)
-- [`mise system brew <SUBCOMMAND>`](/cli/system/brew.md)
-- [`mise system brew tap [-n --dry-run] <TAP> [URL]`](/cli/system/brew/tap.md)
-- [`mise system brew untap [-n --dry-run] <TAPS>…`](/cli/system/brew/untap.md)
 - [`mise system install [FLAGS] [PACKAGE]…`](/cli/system/install.md)
 - [`mise system status [-J --json] [--missing]`](/cli/system/status.md)
 - [`mise system upgrade [FLAGS] [PACKAGE]…`](/cli/system/upgrade.md)

docs/cli/system.md

@@ -21,7 +21,6 @@ with `chsh -s`.
 
 ## Subcommands
 
-- [`mise system brew <SUBCOMMAND>`](/cli/system/brew.md)
 - [`mise system install [FLAGS] [PACKAGE]…`](/cli/system/install.md)
 - [`mise system status [-J --json] [--missing]`](/cli/system/status.md)
 - [`mise system upgrade [FLAGS] [PACKAGE]…`](/cli/system/upgrade.md)

docs/system-packages/brew.md

@@ -20,39 +20,18 @@ bottle. Formulae without a usable bottle are built from source, also without
 Homebrew (see [Source formulae](#source-formulae)). mise never shells out to
 `brew` for homebrew/core formulae.
 
-Third-party taps are supported when Homebrew itself is installed. Tapped
-formulae are delegated to a real `brew` command; use the same
-fully-qualified formula name you would pass to `brew install`:
-
-```toml
-[system.packages]
-"brew:railwaycat/emacsmacport/emacs-mac" = "latest"
-```
-
-For non-GitHub taps, or taps whose URL cannot be inferred by Homebrew, add a
-tap source. This mirrors `[plugins]`: the key is the tap name and the value
-is the git URL.
+Third-party taps are not installed yet. `[system.brew.taps]` can record tap
+URLs in shared config for future direct tap support, but mise will not proxy
+to a `brew` executable:
 
 ```toml
 [system.brew.taps]
 "acme/tools" = "https://git.example.com/acme/homebrew-tools.git"
-
-[system.packages]
-"brew:acme/tools/widget" = "latest"
 ```
 
-Before installing or upgrading tapped formulae, mise runs `brew tap` for any
-configured tap URL and then `brew update-if-needed` so the tap is current.
-
-You can also manage taps imperatively, matching `mise plugins install` /
-`mise plugins uninstall`: these commands shell out to Homebrew and do not
-modify `mise.toml`.
-
-```sh
-mise system brew tap railwaycat/emacsmacport
-mise system brew tap acme/tools https://git.example.com/acme/homebrew-tools.git
-mise system brew untap acme/tools
-```
+Fully-qualified third-party tap formulae such as
+`brew:railwaycat/emacsmacport/emacs-mac` fail with an explicit unsupported
+message until mise can resolve and install them directly.
 
 This exists because shared-library packages — postgres, ffmpeg, imagemagick,
 php — fundamentally can't be served by mise's per-project backends like
@@ -164,11 +143,11 @@ operation.
 
 ## Limitations
 
-- **Formulae only.** Casks (GUI apps) and `brew services` are not
-  implemented.
-- **Tapped formulae require Homebrew.** mise's direct bottle/source installer
-  is only for homebrew/core. Fully-qualified third-party tap formulae are
-  delegated to a real `brew` command.
+- **homebrew/core formulae only.** Casks (GUI apps), `brew services`, and
+  third-party tap formulae are not implemented.
+- **No `brew` executable proxying.** Unsupported Homebrew features fail
+  rather than shelling out to Homebrew. This keeps `brew` usable on machines
+  without Homebrew installed.
 - **Source builds cover the common formula shapes.** mise's formula shim
   implements the widely-used subset of the DSL (see
   [Source formulae](#source-formulae)); formulae that reach beyond it fail

e2e/cli/test_system_status

@@ -29,6 +29,9 @@ EOF
 assert_succeed "mise system status"
 assert_contains "mise system status 2>&1" "invalid system package spec"
 
+# tapped formulae must not proxy to the brew CLI
+assert_fail "mise system install --dry-run brew:owner/tap/formula" "refusing to proxy to \`brew\`"
+
 # empty [system.packages] section
 cat <<EOF >mise.toml
 [system.packages]

mise.usage.kdl

@@ -2898,37 +2898,6 @@ ever acted on when explicitly requested with `mise system install` (or
 `mise bootstrap`). Login shell changes are current-user settings applied
 with `chsh -s`.
 """#
-    cmd brew subcommand_required=#true help="Manage Homebrew taps used by system packages" {
-        long_help #"""
-Manage Homebrew taps used by system packages
-
-These commands shell out to Homebrew and do not modify `mise.toml`. Use
-`[system.brew.taps]` when you want tap sources shared in config.
-"""#
-        cmd tap help="Tap a Homebrew formula repository" {
-            after_long_help #"""
-Examples:
-
-    $ mise system brew tap railwaycat/emacsmacport
-    $ mise system brew tap acme/tools https://git.example.com/acme/homebrew-tools.git
-
-"""#
-            flag "-n --dry-run" help="Print the command that would run without running it"
-            arg <TAP> help="Tap name, e.g. `owner/repo`"
-            arg "[URL]" help="Git URL for non-GitHub or otherwise custom taps" required=#false
-        }
-        cmd untap help="Untap Homebrew formula repositories" {
-            alias remove rm
-            after_long_help #"""
-Examples:
-
-    $ mise system brew untap railwaycat/emacsmacport
-
-"""#
-            flag "-n --dry-run" help="Print the command that would run without running it"
-            arg <TAPS>… help="Tap name(s), e.g. `owner/repo`" var=#true
-        }
-    }
     cmd install help=#"""
 Install missing system packages from `[system.packages]`, apply files
 from `[system.files]` and edits from `[system.edits]`, write macOS

src/cli/system/mod.rs

@@ -1,8 +1,6 @@
 use clap::Subcommand;
 use eyre::Result;
 
-#[cfg(unix)]
-mod brew;
 pub(super) mod driver;
 pub(super) mod install;
 mod status;
@@ -33,8 +31,6 @@ pub struct System {
 
 #[derive(Debug, Subcommand)]
 enum Commands {
-    #[cfg(unix)]
-    Brew(brew::SystemBrew),
     Install(install::SystemInstall),
     Status(status::SystemStatus),
     Upgrade(upgrade::SystemUpgrade),
@@ -44,8 +40,6 @@ enum Commands {
 impl System {
     pub async fn run(self) -> Result<()> {
         match self.command {
-            #[cfg(unix)]
-            Commands::Brew(cmd) => cmd.run().await,
             Commands::Install(cmd) => cmd.run().await,
             Commands::Status(cmd) => cmd.run().await,
             Commands::Upgrade(cmd) => cmd.run().await,

src/cli/system/use.rs

@@ -53,7 +53,6 @@ pub struct SystemUse {
 impl SystemUse {
     pub async fn run(self) -> Result<()> {
         Settings::get().ensure_experimental("mise system")?;
-        let config = crate::config::Config::get().await?;
         let mut by_mgr: IndexMap<String, Vec<PackageRequest>> = IndexMap::new();
         let mut entries: Vec<(String, String)> = vec![];
         for spec in &self.packages {
@@ -72,7 +71,6 @@ impl SystemUse {
                 None => requests.push(request),
             }
         }
-        system::attach_brew_tap_urls(&config, &mut by_mgr);
         // resolve managers before touching the config file so a typo'd
         // manager doesn't get written
         let mgrs = system::packages_from_requests(by_mgr)?;