Refactor algorithm tests to minimize macro code, and move into tests/

The tests only declare a list of tests in the macro, no longer the test functions themselves. This allows better tooling support (e.g. IDE and rustfmt).
2026-08-31 19:44:55 +02:00
parent 6d3a206995
commit df5170f2f5
7 changed files with 1032 additions and 915 deletions
@@ -1,11 +1,398 @@
-mod append_graph_tests {
+use std::fmt::Debug;
+
+use grapherity::algorithms;
+use grapherity::maps::ElementMap;
+use grapherity::testing::fixtures::MakeTestGraph;
+use grapherity::traits::GraphTopology;
+
+macro_rules! dfs_tests {
+    ($T:ty) => {
+        dfs_tests!(@wrap $T,
+            dfs_single_vertex,
+            dfs_disconnected,
+            dfs,
+            dfs_visited_single_vertex,
+            dfs_visited_disconnected,
+            dfs_visited,
+            dfs_find_source,
+            dfs_find_disconnected,
+            dfs_find,
+            dfs_find_where_source_matches,
+            dfs_find_where_disconnected,
+            dfs_find_where_no_match,
+            dfs_find_where_adjacent,
+            dfs_find_where,
+            dfs_find_path_source_equals_target,
+            dfs_find_path_disconnected,
+            dfs_find_path_adjacent,
+            dfs_find_path,
+            dfs_find_path_where_source_matches,
+            dfs_find_path_where_disconnected,
+            dfs_find_path_where_no_match,
+            dfs_find_path_where,
+        );
+    };
+
+    (@wrap $T:ty, $($name:ident),* $(,)?) => {
+        $(
+            #[test]
+            fn $name() {
+                super::$name::<$T>();
+            }
+        )*
+    };
+}
+
+mod append_graph {
    use grapherity::models::AppendGraph;

-    grapherity::dfs_tests!(AppendGraph);
+    dfs_tests!(AppendGraph);
 }

-mod graph_tests {
+mod graph {
    use grapherity::models::Graph;

-    grapherity::dfs_tests!(Graph);
+    dfs_tests!(Graph);
+}
+
+fn dfs_single_vertex<G: MakeTestGraph>()
+where
+    G::Vertex: Debug,
+{
+    let (graph, v) = G::single_vertex();
+    let result = algorithms::dfs(&graph, v);
+    assert!(result.visited[v], "source vertex should be visited");
+    assert_eq!(
+        result.predecessors[v], None,
+        "unexpected predecessor of source vertex"
+    );
+}
+
+fn dfs_disconnected<G: MakeTestGraph>()
+where
+    G::Vertex: Debug,
+{
+    let (graph, vertices) = G::disconnected();
+    let result = algorithms::dfs(&graph, vertices[0]);
+    assert!(
+        result.visited[vertices[0]],
+        "source vertex should be visited"
+    );
+    assert_eq!(
+        result.predecessors[vertices[0]], None,
+        "unexpected predecessor of source vertex"
+    );
+    for &v in &vertices[1..3] {
+        assert!(
+            !result.visited[v],
+            "disconnected vertex {v:?} should not be visited"
+        );
+        assert_eq!(
+            result.predecessors[v], None,
+            "disconnected vertex {v:?} should have no predecessor"
+        );
+    }
+}
+
+fn dfs<G: MakeTestGraph>()
+where
+    G::Vertex: Debug,
+{
+    let (graph, vertices, _, _) = G::standard();
+    let result = algorithms::dfs(&graph, vertices[0]);
+    assert_dfs_visited::<G>(&result.visited, &vertices);
+    assert_dfs_predecessors(&graph, &result.visited, &result.predecessors, &vertices);
+}
+
+fn dfs_visited_single_vertex<G: MakeTestGraph>() {
+    let (graph, v) = G::single_vertex();
+    let visited = algorithms::dfs_visited(&graph, v);
+    assert!(visited[v], "source vertex should be visited");
+}
+
+fn dfs_visited_disconnected<G: MakeTestGraph>()
+where
+    G::Vertex: Debug,
+{
+    let (graph, vertices) = G::disconnected();
+    let visited = algorithms::dfs_visited(&graph, vertices[0]);
+    assert!(visited[vertices[0]], "source vertex should be visited");
+    for &v in &vertices[1..3] {
+        assert!(
+            !visited[v],
+            "disconnected vertex {v:?} should not be visited"
+        );
+    }
+}
+
+fn dfs_visited<G: MakeTestGraph>()
+where
+    G::Vertex: Debug,
+{
+    let (graph, vertices, _, _) = G::standard();
+    let visited = algorithms::dfs_visited(&graph, vertices[0]);
+    assert_dfs_visited::<G>(&visited, &vertices);
+}
+
+fn dfs_find_source<G: MakeTestGraph>() {
+    let (graph, v) = G::single_vertex();
+    assert!(
+        algorithms::dfs_find(&graph, v, v),
+        "source should find itself"
+    );
+}
+
+fn dfs_find_disconnected<G: MakeTestGraph>() {
+    let (graph, vertices) = G::disconnected();
+    assert!(
+        !algorithms::dfs_find(&graph, vertices[0], vertices[1]),
+        "disconnected target should not be found"
+    );
+}
+
+fn dfs_find<G: MakeTestGraph>()
+where
+    G::Vertex: Debug,
+{
+    let (graph, vertices, _, _) = G::standard();
+    for i in 0..10 {
+        assert!(
+            algorithms::dfs_find(&graph, vertices[0], vertices[i]),
+            "vertex {:?} should be reachable from {:?}",
+            vertices[i],
+            vertices[0]
+        );
+    }
+}
+
+fn dfs_find_where_source_matches<G: MakeTestGraph>()
+where
+    G::Vertex: Debug,
+{
+    let (graph, v) = G::single_vertex();
+    assert_eq!(
+        algorithms::dfs_find_where(&graph, v, |u| u == v),
+        Some(v),
+        "source should find itself"
+    );
+}
+
+fn dfs_find_where_disconnected<G: MakeTestGraph>()
+where
+    G::Vertex: Debug,
+{
+    let (graph, vertices) = G::disconnected();
+    assert_eq!(
+        algorithms::dfs_find_where(&graph, vertices[0], |v| v == vertices[1]),
+        None,
+        "disconnected vertex {:?} should not be found",
+        vertices[1]
+    );
+}
+
+fn dfs_find_where_no_match<G: MakeTestGraph>()
+where
+    G::Vertex: Debug,
+{
+    let (graph, vertices, _, _) = G::standard();
+    assert_eq!(
+        algorithms::dfs_find_where(&graph, vertices[0], |_| false),
+        None,
+        "no vertex should match an always-false predicate"
+    );
+}
+
+fn dfs_find_where_adjacent<G: MakeTestGraph>()
+where
+    G::Vertex: Debug,
+{
+    let (graph, vertices, _, _) = G::standard();
+    assert_eq!(
+        algorithms::dfs_find_where(&graph, vertices[0], |v| v == vertices[1]),
+        Some(vertices[1]),
+        "expected to find adjacent vertex"
+    );
+}
+
+fn dfs_find_where<G: MakeTestGraph>()
+where
+    G::Vertex: Debug,
+{
+    let (graph, vertices, _, _) = G::standard();
+    assert_eq!(
+        algorithms::dfs_find_where(&graph, vertices[0], |v| v == vertices[9]),
+        Some(vertices[9]),
+        "expected to find connected vertex"
+    );
+}
+
+fn dfs_find_path_source_equals_target<G: MakeTestGraph>()
+where
+    G::Edge: Debug,
+{
+    let (graph, v) = G::single_vertex();
+    assert_eq!(
+        algorithms::dfs_find_path(&graph, v, v),
+        Some(vec![]),
+        "path from source to itself should be empty"
+    );
+}
+
+fn dfs_find_path_disconnected<G: MakeTestGraph>()
+where
+    G::Edge: Debug,
+{
+    let (graph, vertices) = G::disconnected();
+    assert_eq!(
+        algorithms::dfs_find_path(&graph, vertices[0], vertices[1]),
+        None,
+        "no path should exist to disconnected vertex"
+    );
+}
+
+fn dfs_find_path_adjacent<G: MakeTestGraph>()
+where
+    G::Edge: Debug,
+{
+    let (graph, vertices, e) = G::single_edge();
+    let path = algorithms::dfs_find_path(&graph, vertices[0], vertices[1])
+        .expect("path should exist between adjacent vertices");
+    assert_eq!(
+        path.len(),
+        1,
+        "unexpected path length between adjacent vertices"
+    );
+    assert_eq!(path[0], e, "path should use the connecting edge");
+}
+
+fn dfs_find_path<G: MakeTestGraph>()
+where
+    G::Vertex: Debug,
+    G::Edge: Debug,
+{
+    let (graph, vertices, _, _) = G::standard();
+    let path = algorithms::dfs_find_path(&graph, vertices[0], vertices[9]).expect(&format!(
+        "path should exist between connected vertices {:?} and {:?}",
+        vertices[0], vertices[9]
+    ));
+    assert_valid_path(&graph, &path, vertices[0], vertices[9]);
+}
+
+fn dfs_find_path_where_source_matches<G: MakeTestGraph>()
+where
+    G::Edge: Debug,
+{
+    let (graph, v) = G::single_vertex();
+    assert_eq!(
+        algorithms::dfs_find_path_where(&graph, v, |u| u == v),
+        Some(vec![]),
+        "path from source to itself should be empty"
+    );
+}
+
+fn dfs_find_path_where_disconnected<G: MakeTestGraph>()
+where
+    G::Edge: Debug,
+{
+    let (graph, vertices) = G::disconnected();
+    assert_eq!(
+        algorithms::dfs_find_path_where(&graph, vertices[0], |v| v == vertices[1]),
+        None,
+        "no path should exist to disconnected vertex"
+    );
+}
+
+fn dfs_find_path_where_no_match<G: MakeTestGraph>()
+where
+    G::Edge: Debug,
+{
+    let (graph, vertices, _, _) = G::standard();
+    assert_eq!(
+        algorithms::dfs_find_path_where(&graph, vertices[0], |_| false),
+        None,
+        "no path should exist when predicate never matches"
+    );
+}
+
+fn dfs_find_path_where<G: MakeTestGraph>()
+where
+    G::Vertex: Debug,
+    G::Edge: Debug,
+{
+    let (graph, vertices, _, _) = G::standard();
+    let path = algorithms::dfs_find_path_where(&graph, vertices[0], |v| v == vertices[9]).expect(
+        &format!(
+            "path should exist between connected vertices {:?} and {:?}",
+            vertices[0], vertices[9]
+        ),
+    );
+    assert_valid_path(&graph, &path, vertices[0], vertices[9]);
+}
+
+fn assert_dfs_visited<G: GraphTopology>(
+    visited: &ElementMap<G::Vertex, bool>,
+    vertices: &[G::Vertex],
+) where
+    G::Vertex: Debug,
+{
+    for i in 0..10 {
+        assert!(
+            visited[vertices[i]],
+            "vertex {:?} should be visited",
+            vertices[i]
+        );
+    }
+}
+
+fn assert_dfs_predecessors<G: GraphTopology>(
+    graph: &G,
+    visited: &ElementMap<G::Vertex, bool>,
+    predecessors: &ElementMap<G::Vertex, Option<G::Vertex>>,
+    vertices: &[G::Vertex],
+) where
+    G::Vertex: Debug,
+{
+    assert_eq!(
+        predecessors[vertices[0]], None,
+        "source should have no predecessor"
+    );
+    for i in 1..10 {
+        let v = vertices[i];
+        let p = predecessors[v].expect(&format!("vertex {v:?} should have a predecessor"));
+        assert!(
+            visited[p],
+            "predecessor {p:?} of vertex {v:?} should be visited"
+        );
+        assert!(
+            graph.are_adjacent(v, p),
+            "predecessor {p:?} of vertex {v:?} should be adjacent"
+        );
+    }
+}
+
+fn assert_valid_path<G: GraphTopology>(
+    graph: &G,
+    path: &[G::Edge],
+    source: G::Vertex,
+    target: G::Vertex,
+) where
+    G::Vertex: Debug,
+    G::Edge: Debug,
+{
+    assert!(!path.is_empty(), "path should be non-empty");
+    // Walks the path: tracks current vertex, confirm each edge is incident to it.
+    let mut current = source;
+    for (i, &e) in path.iter().enumerate() {
+        let (v1, v2) = graph.incident_vertices(e);
+        assert_ne!(v1, v2, "path should not contain loop edge {e:?}");
+        assert!(
+            v1 == current || v2 == current,
+            "path edge {e:?} (idx {i}, {v1:?} to {v2:?}) not incident to vertex {current:?}"
+        );
+        current = if v1 == current { v2 } else { v1 };
+    }
+    assert_eq!(
+        current, target,
+        "path should end at target {target:?}, but ended at {current:?}"
+    );
 }