# Plugin Dependency Resolution

## Module
Plugin

## Status
VERIFIED

## Description
Plugin dependency resolution with resolver service, interface, and comprehensive tests.

## Implementation Details
- **PluginDependencyResolver**: `src/Plugin/StellaOps.Plugin.Host/Dependencies/PluginDependencyResolver.cs` -- topological sorting of plugin manifests for load order; cycle detection via DFS with CircularDependencyError reporting; version constraint parsing (>=, >, <=, <, =, ~pessimistic, ^compatible); AreDependenciesSatisfied/GetMissingDependencies for optional dependency support; reverse load order for unload sequence
- **IPluginDependencyResolver**: `src/Plugin/StellaOps.Plugin.Host/Dependencies/IPluginDependencyResolver.cs` -- interface: ResolveLoadOrder, ResolveUnloadOrder, AreDependenciesSatisfied, GetMissingDependencies, ValidateDependencyGraph
- **DependencyGraph**: `src/Plugin/StellaOps.Plugin.Host/Dependencies/DependencyGraph.cs` -- graph data structure with AddNode, AddEdge, HasNode, GetDependents
- **Source**: Feature matrix scan

## E2E Test Plan
- [x] Verify topological sort produces correct load order for a dependency chain
- [x] Test circular dependency detection reports correct cycle paths
- [x] Verify version constraint matching for all operators (>=, >, <=, <, =, ~, ^)
- [x] Test unload order is reverse of load order
- [x] Verify optional dependencies do not block loading when missing

## Verification

**Run ID**: run-001
**Date**: 2026-02-10 (UTC)

### Implementation Coverage
- **PluginDependencyResolver**: 320 lines implementing topological sort with DFS cycle detection, version constraint parsing for 7 operators (>=, >, <=, <, =, ~pessimistic, ^compatible), optional dependency handling
- **DependencyGraph**: 225 lines implementing bidirectional graph with AddNode, AddEdge, HasNode, GetDependents, topological traversal support

### Test Coverage
- **DependencyResolverTests**: 12 tests covering topological sort, circular dependency detection, version constraints, optional dependencies
- **DependencyGraphTests**: 7 tests covering graph construction, edge management, dependent retrieval
- Total: 19 tests, all PASS

### Build Status
- Build: PASS (0 errors, 0 warnings)
- Tests: PASS (314/314 plugin tests pass)

### Verdict
**PASS** - Plugin dependency resolution verified. Topological sort produces correct load order for dependency chains. Circular dependency detection reports accurate cycle paths via DFS. Version constraint matching works for all 7 operators (>=, >, <=, <, =, ~, ^). Unload order is reverse of load order. Optional dependencies do not block loading when missing.

## Recheck (Run-002)
- **Verified**: 2026-02-10
- **Method**: Tier 2d deterministic integration replay.
- **Tests**: PASS (`src/Plugin/__Tests/StellaOps.Plugin.Host.Tests`: 105/105; module matrix: 314/314).
- **Tier 2 Evidence**: `docs/qa/feature-checks/runs/plugin/plugin-dependency-resolution/run-002/tier2-integration-check.json`
- **Outcome**: Dependency resolution/load-order behavior remains stable.


## Recheck (Run-003)
- **Verified**: 2026-02-10
- **Method**: Tier 2d deterministic integration replay (serialized project execution).
- **Tests**: PASS (`src/Plugin/__Tests/StellaOps.Plugin.Host.Tests`: 105/105; module matrix: 314/314).
- **Tier 2 Evidence**: `docs/qa/feature-checks/runs/plugin/plugin-dependency-resolution/run-003/tier2-integration-check.json`
- **Outcome**: Dependency resolution/load-order behavior remains stable.

## Recheck (Run-004)
- **Verified**: 2026-02-10
- **Method**: Tier 2d deterministic integration replay (serialized project execution).
- **Tests**: PASS (`src/Plugin/__Tests/StellaOps.Plugin.Host.Tests`: 105/105; module matrix: 314/314).
- **Tier 2 Evidence**: `docs/qa/feature-checks/runs/plugin/plugin-dependency-resolution/run-004/tier2-integration-check.json`
- **Outcome**: Dependency graph/load-order behavior remains healthy.

## Recheck (Run-005)
- **Verified**: 2026-02-10
- **Method**: Tier 2d deterministic integration replay (serialized project execution).
- **Tests**: PASS (`src/Plugin/__Tests/StellaOps.Plugin.Host.Tests`: 105/105; module matrix: 314/314).
- **Tier 2 Evidence**: `docs/qa/feature-checks/runs/plugin/plugin-dependency-resolution/run-005/tier2-integration-check.json`
- **Outcome**: Checked plugin behavior remains healthy in follow-up replay.
## Recheck (Run-006)
- **Verified**: 2026-02-10
- **Method**: Tier 2d deterministic integration replay (serialized project execution).
- **Tests**: PASS (module matrix: 314/314).
- **Tier 2 Evidence**: docs/qa/feature-checks/runs/plugin/plugin-dependency-resolution/run-006/tier2-integration-check.json
- **Outcome**: Checked plugin behavior remains healthy in continued replay.

## Recheck (Run-007)
- **Verified**: 2026-02-10
- **Method**: Tier 2d deterministic integration replay (serialized project execution).
- **Tests**: PASS (module matrix: 314/314).
- **Tier 2 Evidence**: docs/qa/feature-checks/runs/plugin/plugin-dependency-resolution/run-007/tier2-integration-check.json
- **Outcome**: Checked plugin behavior remains healthy in continued replay.

## Recheck (Run-008)
- **Verified**: 2026-02-10
- **Method**: Tier 2d deterministic integration replay (serialized module matrix).
- **Tests**: PASS (Plugin matrix 314/314: Abstractions 79, Host 105, Registry 65, Sandbox 47, SDK 7, HelloWorld sample 11).
- **Tier 2 Evidence**: docs/qa/feature-checks/runs/plugin/plugin-dependency-resolution/run-008/tier2-integration-check.json
- **Outcome**: Checked Plugin behavior remains healthy in continued replay.


## Recheck (Run-009)
- **Verified**: 2026-02-10
- **Method**: Tier 2d deterministic integration replay (serialized module matrix).
- **Tests**: PASS (Plugin matrix 314/314: Abstractions 79, Host 105, Registry 65, Sandbox 47, SDK 7, HelloWorld sample 11).
- **Tier 2 Evidence**: docs/qa/feature-checks/runs/plugin/plugin-dependency-resolution/run-009/tier2-integration-check.json
- **Outcome**: Checked Plugin behavior remains healthy in continued replay.


## Recheck (Run-010)
- **Verified**: 2026-02-10
- **Method**: Tier 2d deterministic integration replay.
- **Tests**: PASS (Abstractions 79/79, Host 105/105, Registry 65/65, Sandbox 47/47, SDK 7/7, HelloWorld sample 11/11; total 314/314).
- **Tier 2 Evidence**: docs/qa/feature-checks/runs/plugin/plugin-dependency-resolution/run-010/tier2-integration-check.json
- **Outcome**: Checked plugin behavior remains healthy in continued replay.
## Recheck (Run-011)
- **Verified**: 2026-02-10
- **Method**: Tier 2d deterministic integration replay.
- **Tests**: PASS (Abstractions 79/79, Host 105/105, Registry 65/65, Sandbox 47/47, SDK 7/7, HelloWorld sample 11/11; total 314/314).
- **Tier 2 Evidence**: docs/qa/feature-checks/runs/plugin/plugin-dependency-resolution/run-011/tier2-integration-check.json
- **Outcome**: Checked plugin behavior remains healthy in continued replay.
## Recheck (Run-012)
- **Verified**: 2026-02-10
- **Method**: Tier 2d serialized plugin replay.
- **Tests**: PASS (Abstractions 79/79, Host 105/105, Registry 65/65, Sandbox 47/47, SDK 7/7, HelloWorld 11/11; total 314/314).
- **Tier 2 Evidence**: docs/qa/feature-checks/runs/plugin/plugin-dependency-resolution/run-012/tier2-integration-check.json
- **Outcome**: Checked plugin behavior remains healthy in continued replay.

## Recheck (Run-013)
- **Verified**: 2026-02-10
- **Method**: Tier 2d deterministic integration replay with fresh command-output evidence.
- **Tests**: PASS (105/105; Plugin matrix 314/314: Abstractions 79, Host 105, Registry 65, Sandbox 47, SDK 7, HelloWorld sample 11.)
- **Tier 2 Evidence**: docs/qa/feature-checks/runs/plugin/plugin-dependency-resolution/run-013/tier2-integration-check.json
- **Outcome**: Checked Plugin behavior remains healthy in continued replay.


## Recheck (Run-014)
- **Verified**: 2026-02-11
- **Method**: Tier 2d deterministic integration replay with fresh per-feature command evidence + full suite replay.
- **Tests**: PASS (105/105; module suite 314/314).
- **Tier 2 Evidence**: docs/qa/feature-checks/runs/plugin/plugin-dependency-resolution/run-014/tier2-integration-check.json
- **Outcome**: Dependency resolution checked behavior remains stable with fresh host replay evidence.