Bug 1792224: Do not allow tag tracking with individual-files r=jewilde

Differential Revision: https://phabricator.services.mozilla.com/D158050

python/mozbuild/mozbuild/test/test_manifest.py

@@ -788,6 +788,34 @@ bugzilla:
                     b"""
 ---
 schema: 1
+origin:
+  name: cairo
+  description: 2D Graphics Library
+  url: https://www.cairographics.org/
+  release: version 1.6.4
+  license:
+    - MPL-1.1
+    - LGPL-2.1
+  revision: AA001122334455
+vendoring:
+  url: https://example.com
+  source-hosting: gitlab
+  tracking: tag
+  flavor: individual-files
+  individual-files:
+    - upstream-src: foo
+      dst: bar
+bugzilla:
+  product: Core
+  component: Graphics
+            """.strip(),
+                ),
+                # -------------------------------------------------
+                (
+                    "exception",
+                    b"""
+---
+schema: 1
 origin:
   name: cairo
   description: 2D Graphics Library

python/mozbuild/mozbuild/vendor/moz_yaml.py

@@ -526,6 +526,18 @@ def _schema_1_additional(filename, manifest, require_license_file=True):
                 "If Updatebot tasks are specified, a vendoring url must be included."
             )
 
+    # Because the only way we can determine the latest tag is by doing a local clone,
+    # we don't want to do that for individual-files flavors because those flavors are
+    # usually on gigantic repos we don't want to clone for such a simple thing.
+    if (
+        "vendoring" in manifest
+        and manifest["vendoring"].get("flavor", "regular") == "individual-files"
+        and manifest["vendoring"].get("tracking", "commit") == "tag"
+    ):
+        raise ValueError(
+            "You cannot use tag tracking with the individual-files flavor. (Sorry.)"
+        )
+
     # The Rust and Individual Flavor type precludes a lot of options
     # individual-files could, in theory, use several of these, but until we have a use case let's
     # disallow them so we're not worrying about whether they work. When we need them we can make