readme: fix the api examples and add tests

Author: Johannes Holland

README.md

@@ -61,13 +61,13 @@ converted to a python representation of the respective datatype (e.g. a
 `TPMS_SIG_SCHEME_ECDSA` object).
 
 ```python
-from tpmstream.common.event import events_to_obj
+from tpmstream.common.object import events_to_obj
 from tpmstream.io.binary import Binary
-from tpmstream.spec.commands.commands import Command
+from tpmstream.spec.commands import Command
 from tpmstream.spec.structures.constants import TPM_SU
 
 events = Binary.marshal(tpm_type=Command, buffer=b"\x80\x01\x00\x00\x00\x0c\x00\x00\x01\x44\x00\x00")
-command = events_to_obj(Command, events)
+command = events_to_obj(events)
 
 print(command.parameters.startupType)  # prints TPM_SU.CLEAR
 ```
@@ -76,11 +76,24 @@ Likewise, these python objects can be turned into a sequence of events, again.
 
 
 ```python
-from tpmstream.common.event import obj_to_events
-
-# ...
-
-events = obj_to_events(command)
+from tpmstream.common.object import obj_to_events
+from tpmstream.io.binary import Binary
+from tpmstream.spec.commands import Command
+from tpmstream.spec.commands.commands_handles import TPMS_COMMAND_HANDLES_STARTUP
+from tpmstream.spec.commands.commands_params import TPMS_COMMAND_PARAMS_STARTUP
+from tpmstream.spec.structures.base_types import UINT32
+from tpmstream.spec.structures.constants import TPM_CC, TPM_ST, TPM_SU
+from tpmstream.spec.structures.interface_types import TPMI_ST_COMMAND_TAG
+
+startup_command = Command(
+     tag=TPMI_ST_COMMAND_TAG(TPM_ST.NO_SESSIONS),
+     commandSize=UINT32(12),
+     commandCode=TPM_CC.Startup,
+     handles=TPMS_COMMAND_HANDLES_STARTUP(),
+     parameters=TPMS_COMMAND_PARAMS_STARTUP(startupType=TPM_SU.CLEAR),
+)
+
+events = obj_to_events(startup_command)
 
 # Note that `events` is a generator. You can obtain a list by via `list(events)`
 ```
@@ -93,7 +106,7 @@ format (binary, pretty print, ...).
 ```python
 from tpmstream.io.binary import Binary
 from tpmstream.io.pretty import Pretty
-from tpmstream.spec.commands.commands import Command
+from tpmstream.spec.commands import Command
 
 events = Binary.marshal(tpm_type=Command, buffer=b"\x80\x01\x00\x00\x00\x0c\x00\x00\x01\x44\x00\x00")
 pretty = Pretty.unmarshal(events=events)

test/test_readme.py

@@ -0,0 +1,55 @@
+class TestReadme:
+    def test_marshal_from_bytes(self):
+        from tpmstream.common.object import events_to_obj
+        from tpmstream.io.binary import Binary
+        from tpmstream.spec.commands import Command
+        from tpmstream.spec.structures.constants import TPM_SU
+
+        events = Binary.marshal(
+            tpm_type=Command, buffer=b"\x80\x01\x00\x00\x00\x0c\x00\x00\x01\x44\x00\x00"
+        )
+        command = events_to_obj(events)
+
+        print(command.parameters.startupType)  # prints TPM_SU.CLEAR
+        assert command.parameters.startupType == TPM_SU.CLEAR
+
+    def test_marshal_from_command(self):
+        from tpmstream.common.object import obj_to_events
+        from tpmstream.io.binary import Binary
+        from tpmstream.spec.commands import Command
+        from tpmstream.spec.commands.commands_handles import (
+            TPMS_COMMAND_HANDLES_STARTUP,
+        )
+        from tpmstream.spec.commands.commands_params import TPMS_COMMAND_PARAMS_STARTUP
+        from tpmstream.spec.structures.base_types import UINT32
+        from tpmstream.spec.structures.constants import TPM_CC, TPM_ST, TPM_SU
+        from tpmstream.spec.structures.interface_types import TPMI_ST_COMMAND_TAG
+
+        startup_command = Command(
+            tag=TPMI_ST_COMMAND_TAG(TPM_ST.NO_SESSIONS),
+            commandSize=UINT32(12),
+            commandCode=TPM_CC.Startup,
+            handles=TPMS_COMMAND_HANDLES_STARTUP(),
+            parameters=TPMS_COMMAND_PARAMS_STARTUP(startupType=TPM_SU.CLEAR),
+        )
+
+        events = obj_to_events(startup_command)
+        assert list(events) == list(
+            Binary.marshal(
+                tpm_type=Command,
+                buffer=b"\x80\x01\x00\x00\x00\x0c\x00\x00\x01\x44\x00\x00",
+            )
+        )
+
+    def test_unmarshal(self):
+        from tpmstream.io.binary import Binary
+        from tpmstream.io.pretty import Pretty
+        from tpmstream.spec.commands import Command
+
+        events = Binary.marshal(
+            tpm_type=Command, buffer=b"\x80\x01\x00\x00\x00\x0c\x00\x00\x01\x44\x00\x00"
+        )
+        pretty = Pretty.unmarshal(events=events)
+
+        for line in pretty:
+            print(line)