Potential fix to the tooltip with special characters bug

releasenotes/notes/fix-graphviz-draw-tooltip-3f697d71c4b79e60.yaml

@@ -0,0 +1,23 @@
+---
+fixes:
+  - |
+      Fix to `attr_map_to_string` method not handling escaped characters in tooltip correctly issue, Issue #750
+      :meth:`attr_map_to_string` now escapes characters in tooltip using `serde_json::to_string()`
+      Added relevant test to ensure it escapes characters correctly.
+
+          .. jupyter-execute::
+
+                import rustworkx as rx
+                from rustworkx.visualization import graphviz_draw
+
+                graphviz_draw(
+                    rx.generators.path_graph(2),
+                    filename="graph.svg",
+                    image_type="svg",
+                    node_attr_fn=lambda x: {"label": "the\nlabel", "tooltip": "the\ntooltip"},
+                )
+
+
+
+
+

src/dot_utils.rs

@@ -82,15 +82,12 @@ fn attr_map_to_string<'a>(
     if attrs.is_empty() {
         return Ok("".to_string());
     }
-
     let attr_string = attrs
         .iter()
         .map(|(key, value)| {
-            if key == "label" {
-                format!("{}=\"{}\"", key, value)
-            } else {
-                format!("{}={}", key, value)
-            }
+            let escaped_value = serde_json::to_string(value).unwrap();
+            let escaped_value = &escaped_value[1..escaped_value.len() - 1];
+            format!("{}=\"{}\"", key, escaped_value)
         })
         .collect::<Vec<String>>()
         .join(", ");

tests/visualization/test_graphviz.py

@@ -14,7 +14,7 @@
 import subprocess
 import tempfile
 import unittest
-
+import random
 import rustworkx
 from rustworkx.visualization import graphviz_draw
 
@@ -150,3 +150,33 @@ def test_filename(self):
         self.assertTrue(os.path.isfile("test_graphviz_filename.svg"))
         if not SAVE_IMAGES:
             self.addCleanup(os.remove, "test_graphviz_filename.svg")
+
+    def test_escape_sequences(self):
+        # Create a simple graph
+        graph = rustworkx.generators.path_graph(2)
+
+        escape_sequences = {
+            "\\n": "\n",  # Newline
+            "\\t": "\t",  # Horizontal tab
+            "\\'": "'",  # Single quote
+            '\\"': '"',  # Double quote
+            "\\\\": "\\",  # Backslash
+            "\\r": "\r",  # Carriage return
+            "\\b": "\b",  # Backspace
+            "\\f": "\f",  # Form feed
+        }
+
+        for escaped_seq, raw_seq in escape_sequences.items():
+            def node_attr(node):
+                """
+                Define node attributes including escape sequences for labels and tooltips.
+                """
+                label = f"label{escaped_seq}"
+                tooltip = f"tooltip{escaped_seq}"
+                return {"label": label, "tooltip": tooltip}
+
+            # Draw the graph using graphviz_draw
+            dot_str = graph.to_dot(node_attr)
+
+            # Assert that the escape sequences are correctly placed and escaped in the dot string
+            self.assertIn(escaped_seq, dot_str, f"Escape sequence {escaped_seq} not found in dot output")