From 4885e48805b11713c5e685f7ca467130da382302 Mon Sep 17 00:00:00 2001
From: callumalpass <callumalpass@gmail.com>
Date: Sat, 3 Oct 2026 21:20:07 +1000
Subject: [PATCH] Require invalid_type_pack for schema-level upgrade_from
 violations

---
 05a-data-contracts.md                         |  3 ++-
 .../invalid-empty-baselines/_types/note.md    | 22 +++++++++++++++++++
 .../invalid-empty-baselines/mdbase-pack.yaml  | 11 ++++++++++
 .../_types/note.md                            | 22 +++++++++++++++++++
 .../mdbase-pack.yaml                          | 13 +++++++++++
 tests/v0.3/type-packs/type-packs.yaml         | 22 +++++++++++++++++++
 6 files changed, 92 insertions(+), 1 deletion(-)
 create mode 100644 examples/v0.3/seed-upgrades/invalid-empty-baselines/_types/note.md
 create mode 100644 examples/v0.3/seed-upgrades/invalid-empty-baselines/mdbase-pack.yaml
 create mode 100644 examples/v0.3/seed-upgrades/invalid-incomplete-baseline/_types/note.md
 create mode 100644 examples/v0.3/seed-upgrades/invalid-incomplete-baseline/mdbase-pack.yaml

diff --git a/05a-data-contracts.md b/05a-data-contracts.md
index 299ae0d..ae20025 100644
--- a/05a-data-contracts.md
+++ b/05a-data-contracts.md
@@ -383,7 +383,8 @@ part of the reviewed manifest and its digest. Ordinary seeds are unaffected.
 Engines that do not support this member MUST reject the manifest.
 
 The manifest is invalid (`invalid_type_pack`) when `upgrade_from` appears on a
-resource that is not a seed type, when a baseline's digest is not the SHA-256 of
+resource that is not a seed type, when it is an empty list, when a baseline lacks
+`digest` or `document`, when a baseline's digest is not the SHA-256 of
 its document, when two baselines share a digest, when a baseline's digest equals
 the resource's own digest, when a baseline document's frontmatter `kind` or
 `name` differs from the desired document's, or when a baseline's `version`
diff --git a/examples/v0.3/seed-upgrades/invalid-empty-baselines/_types/note.md b/examples/v0.3/seed-upgrades/invalid-empty-baselines/_types/note.md
new file mode 100644
index 0000000..1d283b5
--- /dev/null
+++ b/examples/v0.3/seed-upgrades/invalid-empty-baselines/_types/note.md
@@ -0,0 +1,22 @@
+---
+kind: mdbase.type
+name: note
+version: 3
+description: A note with a creation date and tags.
+match:
+  where:
+    type: note
+schema:
+  dialect: json-schema-2020-12
+  value:
+    type: object
+    required: [title]
+    properties:
+      title: { type: string }
+      created: { type: string, format: date-time }
+      tags: { type: array, items: { type: string } }
+    additionalProperties: true
+---
+# Note
+
+A note in this collection.
diff --git a/examples/v0.3/seed-upgrades/invalid-empty-baselines/mdbase-pack.yaml b/examples/v0.3/seed-upgrades/invalid-empty-baselines/mdbase-pack.yaml
new file mode 100644
index 0000000..0875bb6
--- /dev/null
+++ b/examples/v0.3/seed-upgrades/invalid-empty-baselines/mdbase-pack.yaml
@@ -0,0 +1,11 @@
+kind: mdbase.type-pack
+id: example.seed-notes
+version: 3.0.0
+name: Seed note example
+resources:
+  - kind: type
+    mode: seed
+    source: _types/note.md
+    target: _types/note.md
+    digest: sha256:57160cce297903e123f876d789d518ed83b1cf790edafae660f43f3d44744065
+    upgrade_from: []
diff --git a/examples/v0.3/seed-upgrades/invalid-incomplete-baseline/_types/note.md b/examples/v0.3/seed-upgrades/invalid-incomplete-baseline/_types/note.md
new file mode 100644
index 0000000..1d283b5
--- /dev/null
+++ b/examples/v0.3/seed-upgrades/invalid-incomplete-baseline/_types/note.md
@@ -0,0 +1,22 @@
+---
+kind: mdbase.type
+name: note
+version: 3
+description: A note with a creation date and tags.
+match:
+  where:
+    type: note
+schema:
+  dialect: json-schema-2020-12
+  value:
+    type: object
+    required: [title]
+    properties:
+      title: { type: string }
+      created: { type: string, format: date-time }
+      tags: { type: array, items: { type: string } }
+    additionalProperties: true
+---
+# Note
+
+A note in this collection.
diff --git a/examples/v0.3/seed-upgrades/invalid-incomplete-baseline/mdbase-pack.yaml b/examples/v0.3/seed-upgrades/invalid-incomplete-baseline/mdbase-pack.yaml
new file mode 100644
index 0000000..203c3e4
--- /dev/null
+++ b/examples/v0.3/seed-upgrades/invalid-incomplete-baseline/mdbase-pack.yaml
@@ -0,0 +1,13 @@
+kind: mdbase.type-pack
+id: example.seed-notes
+version: 3.0.0
+name: Seed note example
+resources:
+  - kind: type
+    mode: seed
+    source: _types/note.md
+    target: _types/note.md
+    digest: sha256:57160cce297903e123f876d789d518ed83b1cf790edafae660f43f3d44744065
+    upgrade_from:
+      - digest: sha256:28887fbf68c97de99bc271209466bbf457a3635b3ed2ee93e6c5bf8213f53c10
+        version: 2
diff --git a/tests/v0.3/type-packs/type-packs.yaml b/tests/v0.3/type-packs/type-packs.yaml
index 86d13dc..b94c93c 100644
--- a/tests/v0.3/type-packs/type-packs.yaml
+++ b/tests/v0.3/type-packs/type-packs.yaml
@@ -433,3 +433,25 @@ groups:
             code: invalid_type_pack
         covers:
           - type_packs.seed_type_upgrade_validation
+      - id: seed-upgrade-invalid-empty-baselines
+        name: "invalid upgrade_from (empty-baselines) rejects the manifest with invalid_type_pack"
+        operation: assess_type_pack
+        input:
+          pack: "examples/v0.3/seed-upgrades/invalid-empty-baselines/mdbase-pack.yaml"
+        expect:
+          valid: false
+          error:
+            code: invalid_type_pack
+        covers:
+          - type_packs.seed_type_upgrade_validation
+      - id: seed-upgrade-invalid-incomplete-baseline
+        name: "invalid upgrade_from (incomplete-baseline) rejects the manifest with invalid_type_pack"
+        operation: assess_type_pack
+        input:
+          pack: "examples/v0.3/seed-upgrades/invalid-incomplete-baseline/mdbase-pack.yaml"
+        expect:
+          valid: false
+          error:
+            code: invalid_type_pack
+        covers:
+          - type_packs.seed_type_upgrade_validation