update-shape.py read_pin refuses update-pin-row, and the pinned validate-pins.py and validate-family.py report shape-pin-row, when a shape pin's files: is not a list, so files: 5, true or 1.5 no longer ends check, apply, shape-doctor.py and the project's own validator in TypeError: ... is not iterable (#290)

shape-doctor.py

@@ -2188,7 +2188,12 @@ def pin_reads_at(ctx: Context, rev: str) -> bool:
     `parse_yaml` -- and `check_pin` makes the checks `read_pin` makes, so
     the two cannot disagree about a pin. Where git gives no blob (no such
     path, no such commit) there is no pin that reads, and `files: 5`, which
-    `read_pin` itself fails with a `TypeError`, does not read either.
+    `check_pin` refuses as `update-pin-row`, does not read either (#290).
+
+    A `TypeError` IS NOT CAUGHT. It was, for that `files: 5`; nothing in a
+    pin's bytes raises one now, so one means a caller out of step with
+    `check_pin`, and the doctor fails loudly rather than answer that no
+    commit holds a pin to put back.
     """
     blob = git_answer(["cat-file", "blob", f"{rev}:./{SHAPE_PIN}"],
                       ctx.root, binary=True)
@@ -2197,8 +2202,8 @@ def pin_reads_at(ctx: Context, rev: str) -> bool:
     us = ctx.update_shape()
     try:
         text = blob.decode("utf-8").replace("\r\n", "\n").replace("\r", "\n")
-        us.check_pin(us.parse_yaml(text), f"{rev}:{SHAPE_PIN}")
-    except (Refusal, us.YamlError, ValueError, TypeError):
+        us.check_pin(us.parse_yaml(text), f"{rev}:{SHAPE_PIN}", ctx.root)
+    except (Refusal, us.YamlError, ValueError):
         return False
     return True
 
@@ -3933,7 +3938,13 @@ def pinned_paths(root: Path) -> set:
     pin = Context._read(root / "contracts" / "shape-pin.yaml")
     if not isinstance(pin, dict):
         return set()
-    return {str(row.get("path")) for row in (pin.get("files") or [])
+    # A `files:` that is not a list pins nothing, as a pin that is not a
+    # mapping pins nothing (#290): `files: 5` was iterated, a TypeError. The
+    # shape-currency row is where that pin is reported.
+    rows = pin.get("files")
+    if not isinstance(rows, list):
+        return set()
+    return {str(row.get("path")) for row in rows
             if isinstance(row, dict) and row.get("path")}
 
 

templates/assembly-root/scripts/validate-pins.py

@@ -418,6 +418,14 @@ def _check_shape_pin(root: Path, manifest: dict, report: Report) -> None:
     pin, rel = _check_shape_pin_header(root, manifest, report)
     before = len(report.findings)
     files = pin.get("files") or []
+    if not isinstance(files, list):
+        # Asked, not assumed (#290): `files: 5` was iterated, and the run
+        # ended in a TypeError with no finding naming the pin.
+        report.finding("shape-pin-row",
+                       f"{rel}: `files:` is {files!r}, not a list of "
+                       "`path:`/`sha256:` rows, so nothing about the copied "
+                       "shape files is actually asserted")
+        return
     if not files:
         report.finding("shape-pin-no-files",
                        f"{rel}: no `files:` rows, so nothing about the copied "

templates/family-root/scripts/validate-family.py

@@ -583,6 +583,14 @@ def _check_shape_pin_files(root: Path, pin: dict, rel: str,
     """
     before = len(report.findings)
     files = pin.get("files") or []
+    if not isinstance(files, list):
+        # Asked, not assumed (#290): `files: 5` was iterated, and the run
+        # ended in a TypeError with no finding naming the pin.
+        report.finding("shape-pin-row",
+                       f"{rel}: `files:` is {files!r}, not a list of "
+                       "`path:`/`sha256:` rows, so nothing about the copied "
+                       "shape files is actually asserted")
+        return
     if not files:
         report.finding("shape-pin-no-files",
                        f"{rel}: no `files:` rows, so nothing about the copied "

tests/test_shape_doctor.py

@@ -3762,6 +3762,12 @@ def pin_with(old: str, new: str):
                  "update-pin-no-files", id="no-files-rows"),
     pytest.param(pin_with(r'^  - path: .*$', '  - nopath: x'),
                  "update-pin-row", id="a-row-with-no-path"),
+    pytest.param(pin_with(r'(?s)^files:.*\Z', 'files: 5\n'),
+                 "update-pin-row", id="files-5-not-a-list"),
+    pytest.param(pin_with(r'(?s)^files:.*\Z', 'files: true\n'),
+                 "update-pin-row", id="files-true-not-a-list"),
+    pytest.param(pin_with(r'(?s)^files:.*\Z', 'files: 1.5\n'),
+                 "update-pin-row", id="files-1.5-not-a-list"),
     pytest.param(lambda text: None, "update-pin-missing",
                  id="a-deleted-pin"),
 ]