cli: Fix switch --mutate-in-place to work outside booted environment

Move the --mutate-in-place handling before get_storage() so it doesn't
require a fully booted ostree environment. This enables use cases like
Anaconda where we're chrooted into a non-booted system.

Closes: #1854
Assisted-by: OpenCode (claude-sonnet-4-20250514)
Signed-off-by: Colin Walters <walters@verbum.org>

Author: cgwalters

crates/lib/src/cli.rs

@@ -1206,31 +1206,29 @@ async fn switch_ostree(
 /// Implementation of the `bootc switch` CLI command.
 #[context("Switching")]
 async fn switch(opts: SwitchOpts) -> Result<()> {
+    // If we're doing an in-place mutation, we shortcut most of the rest of the work here
+    // TODO: what we really want here is Storage::detect_from_root() that also handles
+    // composefs. But for now this just assumes ostree.
+    if opts.mutate_in_place {
+        let target = imgref_for_switch(&opts)?;
+        let deployid = {
+            // Clone to pass into helper thread
+            let target = target.clone();
+            let root = cap_std::fs::Dir::open_ambient_dir("/", cap_std::ambient_authority())?;
+            tokio::task::spawn_blocking(move || {
+                crate::deploy::switch_origin_inplace(&root, &target)
+            })
+            .await??
+        };
+        println!("Updated {deployid} to pull from {target}");
+        return Ok(());
+    }
     let storage = &get_storage().await?;
     match storage.kind()? {
         BootedStorageKind::Ostree(booted_ostree) => {
-            // If we're doing an in-place mutation, we shortcut most of the rest of the work here
-            if opts.mutate_in_place {
-                let target = imgref_for_switch(&opts)?;
-                let deployid = {
-                    // Clone to pass into helper thread
-                    let target = target.clone();
-                    let root =
-                        cap_std::fs::Dir::open_ambient_dir("/", cap_std::ambient_authority())?;
-                    tokio::task::spawn_blocking(move || {
-                        crate::deploy::switch_origin_inplace(&root, &target)
-                    })
-                    .await??
-                };
-                println!("Updated {deployid} to pull from {target}");
-                return Ok(());
-            }
             switch_ostree(opts, storage, &booted_ostree).await
         }
         BootedStorageKind::Composefs(booted_cfs) => {
-            if opts.mutate_in_place {
-                anyhow::bail!("--mutate-in-place is not yet supported for composefs backend");
-            }
             switch_composefs(opts, storage, &booted_cfs).await
         }
     }

tmt/plans/integration.fmf

@@ -140,4 +140,11 @@ execute:
     how: fmf
     test:
       - /tmt/tests/tests/test-31-switch-to-unified
+
+/plan-31-switch-mutate-in-place:
+  summary: switch --mutate-in-place
+  discover:
+    how: fmf
+    test:
+      - /tmt/tests/tests/test-31-switch-mutate-in-place
 # END GENERATED PLANS

tmt/tests/booted/test-switch-mutate-in-place.nu

@@ -0,0 +1,21 @@
+# number: 31
+# tmt:
+#   summary: switch --mutate-in-place
+#   duration: 30m
+#
+use std assert
+use tap.nu
+use bootc_testlib.nu
+
+# See https://github.com/bootc-dev/bootc/issues/1854
+
+let st = bootc status --json | from json
+let is_composefs = ($st.status.booted.composefs? != null)
+if not $is_composefs {
+    # This is aiming to reproduce an environment closer to the Anaconda case
+    # where we're chrooted into a non-booted system. TODO: What we really want
+    # is to add `bootc switch --sysroot` too.
+    mv /run/ostree-booted /run/ostree-booted.orig
+    unshare -m /bin/sh -c 'mount -o remount,rw /sysroot && bootc switch --mutate-in-place quay.io/nosuchimage/image-to-test-switch'
+    tap ok
+}

tmt/tests/tests.fmf

@@ -74,3 +74,8 @@
   summary: Onboard to unified storage, build derived image, and switch to it
   duration: 30m
   test: nu booted/test-switch-to-unified.nu
+
+/test-31-switch-mutate-in-place:
+  summary: switch --mutate-in-place
+  duration: 30m
+  test: nu booted/test-switch-mutate-in-place.nu