Fixing upstream issues (#1436)

Author: Krishn1412

rustworkx-core/fuzz/Cargo.toml

@@ -47,4 +47,11 @@ name = "test_fuzz_contraction"
 path = "fuzz_targets/test_fuzz_contraction.rs"
 test = false
 doc = false
+bench = false
+
+[[bin]]
+name = "test_fuzz_centrality"
+path = "fuzz_targets/test_fuzz_centrality.rs"
+test = false
+doc = false
 bench = false

rustworkx-core/fuzz/fuzz_targets/test_fuzz_centrality.rs

@@ -0,0 +1,60 @@
+#![no_main]
+
+use arbitrary::{Arbitrary, Unstructured};
+use libfuzzer_sys::fuzz_target;
+use rustworkx_core::centrality::closeness_centrality;
+use rustworkx_core::petgraph::graph::UnGraph;
+
+#[derive(Debug, Arbitrary)]
+struct CentralityFuzzInput {
+    edges: Vec<(usize, usize)>,
+    node_count: usize,
+}
+
+macro_rules! assert_almost_equal {
+    ($x:expr, $y:expr, $d:expr, $i:expr, $wf:expr) => {
+        if ($x - $y).abs() >= $d {
+            panic!(
+                "{} != {} within delta of {} at node {} with wf_improved = {}",
+                $x, $y, $d, $i, $wf
+            );
+        }
+    };
+}
+
+fuzz_target!(|data: &[u8]| {
+    if let Ok(input) = CentralityFuzzInput::arbitrary(&mut Unstructured::new(data)) {
+        fuzz_centrality(input);
+    }
+});
+
+fn fuzz_centrality(input: CentralityFuzzInput) {
+    if input.node_count == 0 || input.node_count > 1000 {
+        return;
+    }
+
+    let mut graph = UnGraph::<(), ()>::default();
+    let nodes: Vec<_> = (0..input.node_count).map(|_| graph.add_node(())).collect();
+
+    for (u, v) in input.edges {
+        if u < input.node_count && v < input.node_count {
+            graph.add_edge(nodes[u], nodes[v], ());
+        }
+    }
+
+    let epsilon = 1e-4;
+
+    for &wf_improved in &[true, false] {
+        let seq_output = closeness_centrality(&graph, wf_improved, 200);
+        let par_output = closeness_centrality(&graph, wf_improved, 1);
+
+        let c_seq: Vec<f64> = seq_output.iter().map(|x| x.unwrap()).collect();
+        let c_par: Vec<f64> = par_output.iter().map(|x| x.unwrap()).collect();
+
+        assert_eq!(c_seq.len(), c_par.len(), "Centrality result size mismatch");
+
+        for (i, (a, b)) in c_seq.iter().zip(c_par.iter()).enumerate() {
+            assert_almost_equal!(a, b, epsilon, i, wf_improved);
+        }
+    }
+}