Merge lr_planar changes and update tests

rustworkx-core/src/planar/lr_planar.rs

@@ -704,7 +704,7 @@ where
 /// # Example:
 /// ```rust
 /// use rustworkx_core::petgraph::graph::UnGraph;
-/// use rustworkx_core::planar::{is_planar, LRState};
+/// use rustworkx_core::planar::{is_planar_for_layout, LRState};
 ///
 /// let grid = UnGraph::<(), ()>::from_edges(&[
 ///    // row edges
@@ -713,9 +713,9 @@ where
 ///    (0, 3), (3, 6), (1, 4), (4, 7), (2, 5), (5, 8),
 /// ]);
 /// let mut lr_state = LRState::new(&grid);
-/// assert!(is_planar(&grid, Some(&mut lr_state)))
+/// assert!(is_planar_for_layout(&grid, Some(&mut lr_state)))
 /// ```
-pub fn is_planar<G>(graph: G, state: Option<&mut LRState<G>>) -> bool
+pub fn is_planar_for_layout<G>(graph: G, state: Option<&mut LRState<G>>) -> bool
 where
     G: GraphProp<EdgeType = Undirected>
         + NodeCount
@@ -753,3 +753,40 @@ where
 
     true
 }
+
+/// Check if an undirected graph is planar.
+///
+/// A graph is planar iff it can be drawn in a plane without any edge
+/// intersections.
+///
+/// The planarity check algorithm  is based on the
+/// Left-Right Planarity Test:
+///
+/// [`Ulrik Brandes:  The Left-Right Planarity Test (2009)`](http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.217.9208)
+///
+/// # Example:
+/// ```rust
+/// use rustworkx_core::petgraph::graph::UnGraph;
+/// use rustworkx_core::planar::is_planar;
+///
+/// let grid = UnGraph::<(), ()>::from_edges(&[
+///    // row edges
+///    (0, 1), (1, 2), (3, 4), (4, 5), (6, 7), (7, 8),
+///    // col edges
+///    (0, 3), (3, 6), (1, 4), (4, 7), (2, 5), (5, 8),
+/// ]);
+/// assert!(is_planar(&grid))
+/// ```
+pub fn is_planar<G>(graph: G) -> bool
+where
+    G: GraphProp<EdgeType = Undirected>
+        + NodeCount
+        + EdgeCount
+        + IntoEdges
+        + IntoNodeIdentifiers
+        + NodeIndexable
+        + Visitable,
+    G::NodeId: Hash + Eq + Ord,
+{
+    is_planar_for_layout(graph, None)
+}

rustworkx-core/src/planar/mod.rs

@@ -14,4 +14,4 @@
 
 pub mod lr_planar;
 
-pub use lr_planar::{is_planar, LRState};
+pub use lr_planar::{is_planar, is_planar_for_layout, LRState};

rustworkx-core/tests/test_planar.rs

@@ -13,7 +13,7 @@
 //! Test module for planar graphs.
 
 use rustworkx_core::petgraph::graph::UnGraph;
-use rustworkx_core::planar::{is_planar, LRState};
+use rustworkx_core::planar::{is_planar_for_layout, LRState};
 
 #[test]
 fn test_simple_planar_graph() {
@@ -31,7 +31,7 @@ fn test_simple_planar_graph() {
         (5, 7),
     ]);
     let mut lr_state = LRState::new(&graph);
-    let res = is_planar(&graph, Some(&mut lr_state));
+    let res = is_planar_for_layout(&graph, Some(&mut lr_state));
     assert!(res)
 }
 
@@ -54,7 +54,7 @@ fn test_planar_grid_3_3_graph() {
         (5, 8),
     ]);
     let mut lr_state = LRState::new(&graph);
-    let res = is_planar(&graph, Some(&mut lr_state));
+    let res = is_planar_for_layout(&graph, Some(&mut lr_state));
     assert!(res)
 }
 
@@ -76,7 +76,7 @@ fn test_planar_with_self_loop() {
         (4, 5),
     ]);
     let mut lr_state = LRState::new(&graph);
-    let res = is_planar(&graph, Some(&mut lr_state));
+    let res = is_planar_for_layout(&graph, Some(&mut lr_state));
     assert!(res)
 }
 
@@ -113,23 +113,23 @@ fn test_goldner_harary_planar_graph() {
         (10, 11),
     ]);
     let mut lr_state = LRState::new(&graph);
-    let res = is_planar(&graph, Some(&mut lr_state));
+    let res = is_planar_for_layout(&graph, Some(&mut lr_state));
     assert!(res)
 }
 
 #[test]
 fn test_multiple_components_planar_graph() {
     let graph = UnGraph::<(), ()>::from_edges(&[(1, 2), (2, 3), (3, 1), (4, 5), (5, 6), (6, 4)]);
     let mut lr_state = LRState::new(&graph);
-    let res = is_planar(&graph, Some(&mut lr_state));
+    let res = is_planar_for_layout(&graph, Some(&mut lr_state));
     assert!(res)
 }
 
 #[test]
 fn test_planar_multi_graph() {
     let graph = UnGraph::<(), ()>::from_edges(&[(0, 1), (0, 1), (0, 1), (1, 2), (2, 0)]);
     let mut lr_state = LRState::new(&graph);
-    let res = is_planar(&graph, Some(&mut lr_state));
+    let res = is_planar_for_layout(&graph, Some(&mut lr_state));
     assert!(res)
 }
 
@@ -147,7 +147,7 @@ fn test_k3_3_non_planar() {
         (2, 5),
     ]);
     let mut lr_state = LRState::new(&graph);
-    let res = is_planar(&graph, Some(&mut lr_state));
+    let res = is_planar_for_layout(&graph, Some(&mut lr_state));
     assert_eq!(res, false)
 }
 
@@ -166,7 +166,7 @@ fn test_k5_non_planar() {
         (3, 4),
     ]);
     let mut lr_state = LRState::new(&graph);
-    let res = is_planar(&graph, Some(&mut lr_state));
+    let res = is_planar_for_layout(&graph, Some(&mut lr_state));
     assert_eq!(res, false)
 }
 
@@ -188,7 +188,7 @@ fn test_multiple_components_non_planar() {
         (8, 6),
     ]);
     let mut lr_state = LRState::new(&graph);
-    let res = is_planar(&graph, Some(&mut lr_state));
+    let res = is_planar_for_layout(&graph, Some(&mut lr_state));
     assert_eq!(res, false)
 }
 
@@ -208,7 +208,7 @@ fn test_non_planar() {
         (4, 7),
     ]);
     let mut lr_state = LRState::new(&graph);
-    let res = is_planar(&graph, Some(&mut lr_state));
+    let res = is_planar_for_layout(&graph, Some(&mut lr_state));
     assert_eq!(res, false)
 }
 
@@ -227,7 +227,7 @@ fn test_planar_graph1() {
         (1, 7),
     ]);
     let mut lr_state = LRState::new(&graph);
-    let res = is_planar(&graph, Some(&mut lr_state));
+    let res = is_planar_for_layout(&graph, Some(&mut lr_state));
     assert!(res)
 }
 
@@ -253,7 +253,7 @@ fn test_non_planar_graph2() {
         (2, 8),
     ]);
     let mut lr_state = LRState::new(&graph);
-    let res = is_planar(&graph, Some(&mut lr_state));
+    let res = is_planar_for_layout(&graph, Some(&mut lr_state));
     assert_eq!(res, false)
 }
 
@@ -276,6 +276,6 @@ fn test_non_planar_graph3() {
         (5, 13),
     ]);
     let mut lr_state = LRState::new(&graph);
-    let res = is_planar(&graph, Some(&mut lr_state));
+    let res = is_planar_for_layout(&graph, Some(&mut lr_state));
     assert_eq!(res, false)
 }

src/layout/planar.rs

@@ -20,7 +20,7 @@ use crate::iterators::Pos2DMapping;
 use crate::layout::embedding::{create_embedding, embedding_to_pos, PlanarEmbedding};
 use crate::StablePyGraph;
 use rustworkx_core::dictmap::*;
-use rustworkx_core::planar::{is_planar, LRState};
+use rustworkx_core::planar::{is_planar_for_layout, LRState};
 
 /// If a graph is planar, create a set of position coordinates for a planar
 /// layout that can be passed to a drawer.
@@ -38,7 +38,7 @@ pub fn planar_layout(
 
     // First determine if the graph is planar.
     let mut lr_state = LRState::new(graph);
-    if !is_planar(graph, Some(&mut lr_state)) {
+    if !is_planar_for_layout(graph, Some(&mut lr_state)) {
         Err(GraphNotPlanar::new_err("The input graph is not planar."))
 
     // If planar, create the position coordinates.