added unit testcases and updated changelog

Author: isivaselvan

CHANGELOG.md

@@ -1,5 +1,10 @@
 # Unreleased
 
+## Enhancements
+
+### New resources
+* Added `client.stack_deployments` — list the deployments that belong to a stack. `list(stack_id, options=None)` (`GET /stacks/{stack_id}/stack-deployments`) returns an `Iterator[StackDeployment]`, with optional pagination (`page_size`) and `?include=` (`latest_deployment_run`, `latest_deployment_run.stack_configuration`) via `StackDeploymentListOptions`. The `stack` relationship is hydrated as a typed field; the `latest-deployment-run` relation is reachable via the lossless raw accessors (`deployment.related("latest-deployment-run")`). New models: `StackDeployment`, `StackDeploymentListOptions`, `StackDeploymentIncludeOpt`.
+
 # Released
 # v1.2.0
 

tests/units/test_stack_deployment.py

@@ -0,0 +1,151 @@
+# Copyright IBM Corp. 2025, 2026
+# SPDX-License-Identifier: MPL-2.0
+
+"""Unit tests for the stack_deployment module."""
+
+from unittest.mock import Mock
+
+import pytest
+
+from pytfe._http import HTTPTransport
+from pytfe.errors import InvalidStackIDError
+from pytfe.models.stack import Stack
+from pytfe.models.stack_deployment import (
+    StackDeployment,
+    StackDeploymentIncludeOpt,
+    StackDeploymentListOptions,
+)
+from pytfe.resources.stack_deployment import StackDeployments
+
+
+class TestStackDeployments:
+    """Test the StackDeployments service class."""
+
+    @pytest.fixture
+    def mock_transport(self):
+        """Create a mock HTTPTransport."""
+        return Mock(spec=HTTPTransport)
+
+    @pytest.fixture
+    def service(self, mock_transport):
+        """Create a StackDeployments service with mocked transport."""
+        return StackDeployments(mock_transport)
+
+    @pytest.fixture
+    def stack_deployment_api_data(self):
+        """Typical API response item for a single stack deployment."""
+        return {
+            "id": "st-MWvJsvy1FCg3bnXY-std-simple",
+            "type": "stack-deployments",
+            "attributes": {"name": "simple"},
+            "relationships": {
+                "stack": {
+                    "data": {"id": "st-MWvJsvy1FCg3bnXY", "type": "stacks"}
+                },
+                "latest-deployment-run": {
+                    "data": {
+                        "id": "sdr-vzub48Y4f7sFBk7J",
+                        "type": "stack-deployment-runs",
+                    }
+                },
+            },
+        }
+
+    # ── Model tests ──────────────────────────────────────────────────────────
+
+    def test_stack_deployment_parse(self, stack_deployment_api_data):
+        """StackDeployment parses id, name, and the stack relation."""
+        attrs = dict(stack_deployment_api_data["attributes"])
+        attrs["id"] = stack_deployment_api_data["id"]
+        deployment = StackDeployment.model_validate(attrs)
+        assert deployment.id == "st-MWvJsvy1FCg3bnXY-std-simple"
+        assert deployment.name == "simple"
+
+    def test_list_options_serialization(self):
+        """StackDeploymentListOptions serializes page[size] and include."""
+        opts = StackDeploymentListOptions(
+            page_size=50,
+            include=[StackDeploymentIncludeOpt.LATEST_DEPLOYMENT_RUN],
+        )
+        dumped = opts.model_dump(by_alias=True, exclude_none=True)
+        assert dumped["page[size]"] == 50
+
+    # ── list() tests ─────────────────────────────────────────────────────────
+
+    def test_list_invalid_stack_id_raises(self, service):
+        """list() with an empty stack id raises InvalidStackIDError on iteration."""
+        with pytest.raises(InvalidStackIDError):
+            list(service.list(""))
+
+    def test_list_success(self, service, stack_deployment_api_data):
+        """list() yields StackDeployment objects from paginated results."""
+        service._list = Mock(return_value=[stack_deployment_api_data])
+
+        opts = StackDeploymentListOptions(page_size=20)
+        results = list(service.list(stack_id="st-MWvJsvy1FCg3bnXY", options=opts))
+
+        service._list.assert_called_once_with(
+            path="/api/v2/stacks/st-MWvJsvy1FCg3bnXY/stack-deployments",
+            params={"page[size]": 20},
+        )
+        assert len(results) == 1
+        assert isinstance(results[0], StackDeployment)
+        assert results[0].id == "st-MWvJsvy1FCg3bnXY-std-simple"
+        assert results[0].name == "simple"
+
+    def test_list_hydrates_stack_relation(self, service, stack_deployment_api_data):
+        """list() parses the stack relationship into a typed Stack stub."""
+        service._list = Mock(return_value=[stack_deployment_api_data])
+
+        results = list(service.list(stack_id="st-MWvJsvy1FCg3bnXY"))
+
+        assert isinstance(results[0].stack, Stack)
+        assert results[0].stack.id == "st-MWvJsvy1FCg3bnXY"
+
+    def test_list_latest_run_reachable_raw(self, service, stack_deployment_api_data):
+        """The unmodelled latest-deployment-run relation is reachable losslessly."""
+        service._list = Mock(return_value=[stack_deployment_api_data])
+
+        results = list(service.list(stack_id="st-MWvJsvy1FCg3bnXY"))
+
+        refs = results[0].related("latest-deployment-run")
+        assert refs[0]["id"] == "sdr-vzub48Y4f7sFBk7J"
+        # raw escape-hatch data never leaks into model_dump()
+        assert "relationships" not in results[0].model_dump()
+
+    def test_list_with_include(self, service, stack_deployment_api_data):
+        """list() passes include param as a comma-separated string."""
+        service._list = Mock(return_value=[stack_deployment_api_data])
+
+        opts = StackDeploymentListOptions(
+            include=[
+                StackDeploymentIncludeOpt.LATEST_DEPLOYMENT_RUN,
+                StackDeploymentIncludeOpt.LATEST_DEPLOYMENT_RUN_STACK_CONFIGURATION,
+            ]
+        )
+        list(service.list(stack_id="st-MWvJsvy1FCg3bnXY", options=opts))
+
+        _, kwargs = service._list.call_args
+        assert (
+            kwargs["params"]["include"]
+            == "latest_deployment_run,latest_deployment_run.stack_configuration"
+        )
+
+    def test_list_empty(self, service):
+        """list() returns an empty iterator when no items are returned."""
+        service._list = Mock(return_value=[])
+
+        results = list(service.list(stack_id="st-MWvJsvy1FCg3bnXY"))
+        assert results == []
+
+    def test_list_no_options(self, service, stack_deployment_api_data):
+        """list() works correctly when no options are given."""
+        service._list = Mock(return_value=[stack_deployment_api_data])
+
+        results = list(service.list(stack_id="st-MWvJsvy1FCg3bnXY"))
+
+        service._list.assert_called_once_with(
+            path="/api/v2/stacks/st-MWvJsvy1FCg3bnXY/stack-deployments",
+            params={},
+        )
+        assert len(results) == 1