rust-call-graph

# Rust Call Graph

Visualize function call relationships using LSP call hierarchy.

## Usage

```
/rust-call-graph <function_name> [--depth N] [--direction in|out|both]
```

**Options:**
- `--depth N`: How many levels to traverse (default: 3)
- `--direction`: `in` (callers), `out` (callees), `both`

**Examples:**
- `/rust-call-graph process_request` - Show both callers and callees
- `/rust-call-graph handle_error --direction in` - Show only callers
- `/rust-call-graph main --direction out --depth 5` - Deep callee analysis

## LSP Operations

### 1. Prepare Call Hierarchy

Get the call hierarchy item for a function.

```
LSP(
  operation: "prepareCallHierarchy",
  filePath: "src/handler.rs",
  line: 45,
  character: 8
)
```

### 2. Incoming Calls (Who calls this?)

```
LSP(
  operation: "incomingCalls",
  filePath: "src/handler.rs",
  line: 45,
  character: 8
)
```

### 3. Outgoing Calls (What does this call?)

```
LSP(
  operation: "outgoingCalls",
  filePath: "src/handler.rs",
  line: 45,
  character: 8
)
```

## Workflow

```
User: "Show call graph for process_request"
    │
    ▼
[1] Find function location
    LSP(workspaceSymbol) or Grep
    │
    ▼
[2] Prepare call hierarchy
    LSP(prepareCallHierarchy)
    │
    ▼
[3] Get incoming calls (callers)
    LSP(incomingCalls)
    │
    ▼
[4] Get outgoing calls (callees)
    LSP(outgoingCalls)
    │
    ▼
[5] Recursively expand to depth N
    │
    ▼
[6] Generate ASCII visualization
```

## Output Format

### Incoming Calls (Who calls this?)

```
## Callers of `process_request`

main
└── run_server
    └── handle_connection
        └── process_request  ◄── YOU ARE HERE
```

### Outgoing Calls (What does this call?)

```
## Callees of `process_request`

process_request  ◄── YOU ARE HERE
├── parse_headers
│   └── validate_header
├── authenticate
│   ├── check_token
│   └── load_user
├── execute_handler
│   └── [dynamic dispatch]
└── send_response
    └── serialize_body
```

### Bidirectional (Both)

```
## Call Graph f