Make home directory optional.

src/commands/key/generate.rs

@@ -153,17 +153,24 @@ pub fn generate(
 
         rev_cert
     } else if on_keystore {
-        let dir = sq.home.data_dir(sequoia_directories::Component::Other(
-            "revocation-certificates".into()));
-        std::fs::create_dir_all(&dir)
-            .with_context(|| {
-                format!("While creating {}", dir.display())
-            })?;
+        if let Some(home) = &sq.home {
+            let dir = home.data_dir(sequoia_directories::Component::Other(
+                "revocation-certificates".into()));
+            std::fs::create_dir_all(&dir)
+                .with_context(|| {
+                    format!("While creating {}", dir.display())
+                })?;
 
-        (cert, rev) = gen()?;
-        FileOrStdout::new(
-            Some(dir.join(format!("{}-revocation.pgp",
-                                  cert.fingerprint()))))
+            (cert, rev) = gen()?;
+            FileOrStdout::new(
+                Some(dir.join(format!("{}-revocation.pgp",
+                                      cert.fingerprint()))))
+        } else {
+            return Err(anyhow::anyhow!(
+                "Missing arguments: --rev-cert is mandatory if --home=none is \
+                 given."
+            ));
+        }
     } else {
         return Err(anyhow::anyhow!(
             "Missing arguments: --rev-cert is mandatory if --output is \

src/commands/key/list.rs

@@ -447,7 +447,10 @@ pub fn list(sq: Sq, mut cmd: cli::key::list::Command) -> Result<()> {
         let mut hint = sq.hint(format_args!(
             "There are no secret keys."));
 
-        if sq.key_store_path.is_some() || ! sq.home.is_default_location() {
+        if sq.key_store_path.is_some()
+            || ! sq.home.as_ref()
+            .map(|h| h.is_default_location()).unwrap_or(false)
+        {
             hint = hint.hint(format_args!(
                 "The non-default key store location {} is selected \
                  using the `{}` option.  Consider using the default \

src/main.rs

@@ -301,14 +301,14 @@ fn real_main() -> Result<()> {
         time_is_now,
         policy_as_of,
         policy: &policy,
-        home: if let Some(p) = c.home.as_ref().and_then(|a| a.path()) {
+        home: Some(if let Some(p) = c.home.as_ref().and_then(|a| a.path()) {
             sequoia_directories::Home::new(p)?
         } else {
             sequoia_directories::Home::default()
                 .ok_or(anyhow::anyhow!("no default SEQUOIA_HOME \
                                         on this platform"))?
                 .clone()
-        },
+        }),
         no_rw_cert_store: c.no_cert_store,
         cert_store_path: c.cert_store.as_ref().and_then(|a| a.path()),
         keyrings: c.keyring.clone(),

src/sq.rs

@@ -104,7 +104,7 @@ pub struct Sq<'store, 'rstore>
     pub time_is_now: bool,
     pub policy: &'rstore P<'rstore>,
     pub policy_as_of: SystemTime,
-    pub home: sequoia_directories::Home,
+    pub home: Option<sequoia_directories::Home>,
     // --no-cert-store
     #[deprecated]
     pub no_rw_cert_store: bool,
@@ -161,7 +161,8 @@ impl<'store: 'rstore, 'rstore> Sq<'store, 'rstore> {
         } else if let Ok(path) = std::env::var("PGP_CERT_D") {
             Some(PathBuf::from(path))
         } else {
-            Some(self.home.data_dir(sequoia_directories::Component::CertD))
+            self.home.as_ref()
+                .map(|h| h.data_dir(sequoia_directories::Component::CertD))
         }
     }
 
@@ -366,7 +367,8 @@ impl<'store: 'rstore, 'rstore> Sq<'store, 'rstore> {
         } else if let Some(dir) = self.key_store_path.as_ref() {
             Ok(Some(dir.clone()))
         } else {
-            Ok(Some(self.home.data_dir(sequoia_directories::Component::Keystore)))
+            Ok(self.home.as_ref()
+               .map(|h| h.data_dir(sequoia_directories::Component::Keystore)))
         }
     }