Add test for attractor tool

Author: Notgnoshi

tests/mod.rs

@@ -1,3 +1,4 @@
+mod test_attractor;
 mod test_bundle;
 #[cfg(feature = "cxx-bindings")]
 mod test_geom2graph;

tests/test_attractor.rs

@@ -0,0 +1,23 @@
+use pretty_assertions::assert_eq;
+
+use crate::{CommandExt, tool};
+
+#[test]
+fn test_attractor_simple() {
+    let expected = "\
+        POINT(1 2)\n\
+        POINT(2 4)\n\
+        POINT(3 6)\n\
+    ";
+
+    let output = tool("attractor")
+        .arg("--initial-x=0")
+        .arg("--initial-y=0")
+        .arg("--math=let x_new = x + 1.0;")
+        .arg("--math=let y_new = y + 2.0;")
+        .arg("--iterations=3")
+        .captured_output();
+    assert!(output.status.success());
+    let stdout = String::from_utf8_lossy(&output.stdout);
+    assert_eq!(expected, stdout);
+}