test(py): check roundtrip through CLI (#2332)

Author: ss2165

hugr-py/src/hugr/_serialization/ops.py

@@ -123,14 +123,13 @@ class FunctionValue(BaseValue):
     """A higher-order function value."""
 
     v: Literal["Function"] = Field(default="Function", title="ValueTag")
-    hugr: Any
+    hugr: str
 
     def deserialize(self) -> val.Value:
-        from hugr._serialization.serial_hugr import SerialHugr
         from hugr.hugr import Hugr
 
         # pydantic stores the serialized dictionary because of the "Any" annotation
-        return val.Function(Hugr._from_serial(SerialHugr(**self.hugr)))
+        return val.Function(Hugr.from_str(self.hugr))
 
 
 class TupleValue(BaseValue):

hugr-py/src/hugr/val.py

@@ -298,9 +298,7 @@ def type_(self) -> tys.FunctionType:
         return self.body.entrypoint_op().inner_signature()
 
     def _to_serial(self) -> sops.FunctionValue:
-        return sops.FunctionValue(
-            hugr=self.body._to_serial(),
-        )
+        return sops.FunctionValue(hugr=self.body.to_str())
 
     def to_model(self) -> model.Term:
         module = self.body.to_model()

hugr-py/tests/conftest.py

@@ -156,6 +156,7 @@ def validate(
         return
 
     # Roundtrip checks
+    # 1. just roundtrip with Python
     if isinstance(h, Hugr):
         starting_json = h.to_str()
         h2 = Hugr.from_str(starting_json)
@@ -174,14 +175,24 @@ def validate(
         roundtrip_encoded = loaded.to_str(EnvelopeConfig.TEXT)
         assert encoded == roundtrip_encoded
 
+    # 2. roundtrip through the CLI
 
-def _run_hugr_cmd(serial: bytes, cmd: list[str]):
+    # TODO once model loading is supported in Python
+    # try every combo of input and output formats
+    cmd = [*_base_command(), "convert", "-", "--text"]
+
+    serial = h.to_bytes(EnvelopeConfig.BINARY)
+    out = _run_hugr_cmd(serial, cmd)
+    loaded = Package.from_bytes(out.stdout)
+
+
+def _run_hugr_cmd(serial: bytes, cmd: list[str]) -> subprocess.CompletedProcess[bytes]:
     """Run a HUGR command.
 
     The `serial` argument is the serialized HUGR to pass to the command via stdin.
     """
     try:
-        subprocess.run(cmd, check=True, input=serial, capture_output=True)  # noqa: S603
+        return subprocess.run(cmd, check=True, input=serial, capture_output=True)  # noqa: S603
     except subprocess.CalledProcessError as e:
         error = e.stderr.decode()
         raise RuntimeError(error) from e

specification/schema/hugr_schema_live.json

@@ -759,7 +759,8 @@
                     "type": "string"
                 },
                 "hugr": {
-                    "title": "Hugr"
+                    "title": "Hugr",
+                    "type": "string"
                 }
             },
             "required": [

specification/schema/hugr_schema_strict_live.json

@@ -759,7 +759,8 @@
                     "type": "string"
                 },
                 "hugr": {
-                    "title": "Hugr"
+                    "title": "Hugr",
+                    "type": "string"
                 }
             },
             "required": [

specification/schema/testing_hugr_schema_live.json

@@ -759,7 +759,8 @@
                     "type": "string"
                 },
                 "hugr": {
-                    "title": "Hugr"
+                    "title": "Hugr",
+                    "type": "string"
                 }
             },
             "required": [

specification/schema/testing_hugr_schema_strict_live.json

@@ -759,7 +759,8 @@
                     "type": "string"
                 },
                 "hugr": {
-                    "title": "Hugr"
+                    "title": "Hugr",
+                    "type": "string"
                 }
             },
             "required": [