core: Fix usroverlay regression

The `/sysroot` writability regressed this, and add a missing test
case for this.

Signed-off-by: Colin Walters <[email protected]>

Author: cgwalters

crates/lib/src/cli.rs

@@ -1336,10 +1336,12 @@ async fn run_from_opt(opt: Opt) -> Result<()> {
         }
         Opt::Edit(opts) => edit(opts).await,
         Opt::UsrOverlay => {
-            let storage = &get_storage().await?;
-            match storage.kind()? {
-                BootedStorageKind::Ostree(_) => usroverlay().await,
-                BootedStorageKind::Composefs(_) => composefs_usr_overlay(),
+            use crate::store::Environment;
+            let env = Environment::detect()?;
+            match env {
+                Environment::OstreeBooted => usroverlay().await,
+                Environment::ComposefsBooted(_) => composefs_usr_overlay(),
+                _ => anyhow::bail!("usroverlay only applies on booted hosts"),
             }
         }
         Opt::Container(opts) => match opts {

tmt/plans/integration.fmf

@@ -106,6 +106,13 @@ execute:
       enabled: false
       because: tmt-reboot does not work with systemd reboot in testing farm environment (see bug-soft-reboot.md)
 
+/test-23-usroverlay:
+  summary: Usroverlay
+  discover:
+    how: fmf
+    test:
+        - /tmt/tests/test-23-usroverlay
+
 /test-28-factory-reset:
   summary: Factory reset
   discover:

tmt/tests/booted/test-usroverlay.nu

@@ -0,0 +1,31 @@
+# Verify that bootc usroverlay works
+use std assert
+use tap.nu
+
+bootc status
+
+# We should start out in a non-writable state on each boot
+let is_writable = (do -i { /bin/test -w /usr } | complete | get exit_code) == 0
+assert (not $is_writable)
+
+def initial_run [] {
+    bootc usroverlay
+    let is_writable = (do -i { /bin/test -w /usr } | complete | get exit_code) == 0
+    assert ($is_writable)
+    
+    tmt-reboot
+}
+
+# The second boot; verify we're in the derived image
+def second_boot [] {
+    # Nothing, we already verified non-writability above
+}
+
+def main [] {
+    # See https://tmt.readthedocs.io/en/stable/stories/features.html#reboot-during-test
+    match $env.TMT_REBOOT_COUNT? {
+        null | "0" => initial_run,
+        "1" => second_boot,
+        $o => { error make { msg: $"Invalid TMT_REBOOT_COUNT ($o)" } },
+    }
+}

tmt/tests/test-23-usroverlay.fmf

@@ -0,0 +1,3 @@
+summary: Execute tests for bootc usrover
+test: nu booted/test-usroverlay.nu
+duration: 30m