fix(vendor): rebuild a dir copy that has no inventory on re-vendor

Ledgers written before #300 record no file inventory for cargo, Go and
composer copies, and a copy past the inventory cap records none either.
Exact restore refuses such an entry, and vendor sent every same-uuid
entry that was not healthy to that same restore, so the re-vendor the
error suggested failed with vendor_redownload_failed on every run.

A dir-shaped entry without an inventory now skips the exact restore and
goes to the backend, which rebuilds the copy from a fresh verified
download as vendor did before #300. The file-shaped entry without a
SHA-256 still refuses. Both restore refusals now name the remedy that
records a new fingerprint: vendor --revert and then vendor.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01NEUik3Qo9HQtYGVEAMs1Di

Author: claude

crates/socket-patch-cli/src/commands/vendor.rs

@@ -2445,9 +2445,15 @@ pub(crate) async fn vendor_records_reusing(
                 }
             }
 
-            if let Some(entry) =
-                lookup_entry(&state.entries, candidate).filter(|entry| entry.uuid == record.uuid)
-            {
+            // A dir-shaped entry with no file inventory (vendored before
+            // inventories were recorded, or past the inventory cap) gives an
+            // exact restore nothing to check a download against: the backend
+            // below rebuilds its copy from a fresh verified download instead.
+            if let Some(entry) = lookup_entry(&state.entries, candidate).filter(|entry| {
+                entry.uuid == record.uuid
+                    && (entry.artifact.file_inventory.is_some()
+                        || vendor::artifact_is_file_shaped(&entry.artifact.path))
+            }) {
                 if vendor::check_vendored_artifact(&common.cwd, entry, record).await
                     != vendor::ArtifactHealth::Healthy
                     || (entry.artifact.sha256.is_empty()

crates/socket-patch-cli/tests/vendor/vendor_rerun_no_network_e2e.rs

@@ -689,6 +689,76 @@ fn cargo_rerun_over_a_drifted_copy_still_fetches_and_reports_it() {
     );
 }
 
+/// A copy vendored before inventories were recorded (a 4.0.0 ledger entry
+/// has no `fileInventory`) gives an exact redownload nothing to check, so a
+/// re-vendor over its deleted copy rebuilds it through the backend from a
+/// fresh verified download instead of refusing on every run.
+#[test]
+fn cargo_rerun_over_a_missing_pre_inventory_copy_rebuilds_it() {
+    const PURL: &str = "pkg:cargo/cfg-if@1.0.4";
+    const UUID: &str = "2b1f6c1e-8d3a-4f6b-9c2d-7e5a9b1c3d0c";
+    const PRISTINE: &[u8] = b"pub fn cfg() {}\n";
+    const PATCHED: &[u8] = b"pub fn cfg() { /* patched */ }\n";
+    let tmp = tempfile::tempdir().unwrap();
+    let root = tmp.path().join("proj");
+    let cargo_home = tmp.path().join("cargo-home");
+    let krate = cargo_home.join("registry/src/index.crates.io-6f17d22bba15001f/cfg-if-1.0.4");
+    std::fs::create_dir_all(krate.join("src")).unwrap();
+    std::fs::write(krate.join("src/lib.rs"), PRISTINE).unwrap();
+    std::fs::write(
+        krate.join("Cargo.toml"),
+        "[package]\nname = \"cfg-if\"\nversion = \"1.0.4\"\n",
+    )
+    .unwrap();
+    std::fs::create_dir_all(&root).unwrap();
+    std::fs::write(
+        root.join("Cargo.toml"),
+        "[package]\nname = \"app\"\nversion = \"0.1.0\"\n\n[dependencies]\ncfg-if = \"1\"\n",
+    )
+    .unwrap();
+    std::fs::write(
+        root.join("Cargo.lock"),
+        format!(
+            "version = 4\n\n\
+             [[package]]\nname = \"app\"\nversion = \"0.1.0\"\n\
+             dependencies = [\n \"cfg-if\",\n]\n\n\
+             [[package]]\nname = \"cfg-if\"\nversion = \"1.0.4\"\n\
+             source = \"registry+https://github.com/rust-lang/crates.io-index\"\n\
+             checksum = \"{}\"\n",
+            "9".repeat(64)
+        ),
+    )
+    .unwrap();
+    write_manifest(&root, PURL, UUID, "package/src/lib.rs", PRISTINE, PATCHED);
+    let home = cargo_home.to_string_lossy().into_owned();
+    let env = [("CARGO_HOME", home.as_str())];
+    let dead = dead_endpoint();
+
+    let (code, v, stderr) = run_vendor(&root, &dead, &[], &env);
+    assert_eq!(code, 0, "{v:#}\n{stderr}");
+    std::fs::remove_dir_all(&krate).unwrap();
+    let state_path = root.join(".socket/vendor/state.json");
+    let mut state: serde_json::Value =
+        serde_json::from_slice(&std::fs::read(&state_path).unwrap()).unwrap();
+    let artifact = state["entries"][PURL]["artifact"]
+        .as_object_mut()
+        .expect("the ledger records the crate");
+    assert!(artifact.remove("fileInventory").is_some(), "{v:#}");
+    std::fs::write(&state_path, serde_json::to_vec_pretty(&state).unwrap()).unwrap();
+    std::fs::remove_dir_all(root.join(format!(".socket/vendor/cargo/{UUID}"))).unwrap();
+
+    let (code, v, stderr) = run_vendor(&root, &dead, &[], &env);
+    assert_eq!(code, 0, "{v:#}\n{stderr}");
+    assert!(
+        !purl_events(&v, PURL).contains(&("failed", "vendor_redownload_failed")),
+        "{v:#}"
+    );
+    let copy_lib = root.join(format!(
+        ".socket/vendor/cargo/{UUID}/cfg-if-1.0.4/src/lib.rs"
+    ));
+    assert_eq!(std::fs::read(&copy_lib).unwrap(), PATCHED);
+}
+
 // ── cargo: the service path needs no pristine source ─────────────────────
 
 /// A `.crate`: a tar.gz with a single `{prefix}/` top-level dir.

crates/socket-patch-core/src/vendor/redownload.rs

@@ -47,6 +47,16 @@ async fn download_archive(
         .or_else(used)
 }
 
+// Without the ledger's fingerprint no download can be proven to be the
+// recorded artifact. A revert drops the entry, so the following `vendor`
+// downloads afresh and records a new fingerprint.
+const NO_ARCHIVE_SHA256: &str = "the ledger has no archive SHA-256; restore it from version \
+     control, or run `socket-patch vendor --revert` and then `socket-patch vendor` to vendor \
+     it again";
+const NO_FILE_INVENTORY: &str = "the ledger has no complete file inventory; restore it from \
+     version control, or run `socket-patch vendor --revert` and then `socket-patch vendor` to \
+     vendor it again";
+
 /// Restore only the recorded artifact. Project wiring and ledger are never written.
 pub async fn restore(
     root: &Path,
@@ -93,10 +103,10 @@ pub async fn restore(
     let file_shaped = !super::verify::is_vlt_dir_entry(entry)
         && super::verify::artifact_is_file_shaped(&entry.artifact.path);
     if file_shaped && entry.artifact.sha256.is_empty() {
-        return Err("the ledger has no archive SHA-256; restore from version control or explicitly re-vendor".into());
+        return Err(NO_ARCHIVE_SHA256.into());
     }
     if !file_shaped && entry.artifact.file_inventory.is_none() {
-        return Err("the ledger has no complete file inventory; restore from version control or explicitly re-vendor".into());
+        return Err(NO_FILE_INVENTORY.into());
     }
     let socket = root.join(".socket");
     tokio::fs::create_dir_all(&socket)
@@ -278,7 +288,11 @@ pub async fn restore(
             }
         }
         {
-            let inventory = entry.artifact.file_inventory.as_ref().ok_or("the ledger has no complete file inventory; restore from version control or explicitly re-vendor")?;
+            let inventory = entry
+                .artifact
+                .file_inventory
+                .as_ref()
+                .ok_or(NO_FILE_INVENTORY)?;
             let uuid = (entry.ecosystem == "cargo").then_some(entry.uuid.as_str());
             super::verify::verify_dir_inventory(&stage, inventory, uuid).await?;
         }
@@ -566,6 +580,10 @@ mod tests {
             .await
             .unwrap_err();
         assert!(error.contains("no archive SHA-256"), "{error}");
+        assert!(
+            error.contains("`socket-patch vendor --revert` and then `socket-patch vendor`"),
+            "the refusal names the remedy that records a new fingerprint: {error}"
+        );
         assert!(server.received_requests().await.unwrap().is_empty());
         assert_eq!(tree_snapshot(root.path()), before);
     }
@@ -685,15 +703,19 @@ mod tests {
         let before = tree_snapshot(root.path());
         entry.artifact.file_inventory = None;
         server.reset().await;
-        assert!(restore(
+        let error = restore(
             root.path(),
             &entry,
             &record(),
-            &service_cfg(&server.uri(), VendorSource::Service, false)
+            &service_cfg(&server.uri(), VendorSource::Service, false),
         )
         .await
-        .unwrap_err()
-        .contains("no complete file inventory"));
+        .unwrap_err();
+        assert!(error.contains("no complete file inventory"), "{error}");
+        assert!(
+            error.contains("`socket-patch vendor --revert` and then `socket-patch vendor`"),
+            "the refusal names the remedy that records a new inventory: {error}"
+        );
         assert!(server.received_requests().await.unwrap().is_empty());
         assert_eq!(tree_snapshot(root.path()), before);
         entry.ecosystem = "npm".into();