Module cycles 

Cycle detection for the blocking dependency graph.

Overview

Blocking dependencies form a directed graph. Cycles make items permanently stuck (each item waits on another in the loop). This module detects cycles when a new blocking edge is added and returns a warning with the cycle path.

Design

• DFS-based: Standard depth-first search from the target of the new edge, looking for a path back to the source. This detects the cycle that the new edge closes.
• Warn, don’t block: Cycles are user errors, not system errors. The link is still added to the CRDT; the caller is responsible for surfacing the warning.
• O(V+E): Each detection check visits each node and edge at most once.

Usage

use bones_core::graph::cycles::{detect_cycle_on_add, CycleWarning};
use bones_core::graph::blocking::BlockingGraph;

let graph = BlockingGraph::from_states(&states);
if let Some(warning) = detect_cycle_on_add(&graph, "bn-task1", "bn-task2") {
    eprintln!("Warning: {warning}");
}

Structs

CycleWarning

A warning emitted when a new blocking edge would close a cycle.

Functions

detect_cycle_on_add

Detect whether adding a blocking edge from → to (meaning from is blocked by to) would create a cycle in the blocking graph.

find_all_cycles

Detect all cycles in the blocking graph using Tarjan-style DFS.

has_cycles

Check whether the blocking graph has any cycles at all.