Assert against infinite values of control points in CatmullRomSpline (#131820)

When providing infinite values for the control points of CatmullRomSpline, a StackOverflowError occurs. This asserts against that and provides a helpful error message. 

Fixes flutter/flutter#131246

Author: Piinks

packages/flutter/lib/src/animation/curves.dart

@@ -705,6 +705,27 @@ class CatmullRomSpline extends Curve2D {
     Offset? startHandle,
     Offset? endHandle,
   }) {
+    assert(
+      startHandle == null || startHandle.isFinite,
+      'The provided startHandle of CatmullRomSpline must be finite. The '
+      'startHandle given was $startHandle.'
+    );
+    assert(
+      endHandle == null || endHandle.isFinite,
+      'The provided endHandle of CatmullRomSpline must be finite. The endHandle '
+      'given was $endHandle.'
+    );
+    assert(() {
+      for (int index = 0; index < controlPoints.length; index++) {
+        if (!controlPoints[index].isFinite) {
+          throw FlutterError(
+            'The provided CatmullRomSpline control point at index $index is not '
+            'finite. The control point given was ${controlPoints[index]}.'
+          );
+        }
+      }
+      return true;
+    }());
     // If not specified, select the first and last control points (which are
     // handles: they are not intersected by the resulting curve) so that they
     // extend the first and last segments, respectively.

packages/flutter/test/animation/curves_test.dart

@@ -305,6 +305,28 @@ void main() {
     expect(() {
       CatmullRomSpline(const <Offset>[Offset.zero, Offset.zero, Offset.zero, Offset.zero], tension: 2.0);
     }, throwsAssertionError);
+    expect(() {
+      CatmullRomSpline(
+        const <Offset>[Offset(double.infinity, 0.0), Offset.zero, Offset.zero, Offset.zero],
+      ).generateSamples();
+    }, throwsAssertionError);
+    expect(() {
+      CatmullRomSpline(
+        const <Offset>[Offset(0.0, double.infinity), Offset.zero, Offset.zero, Offset.zero],
+      ).generateSamples();
+    }, throwsAssertionError);
+    expect(() {
+      CatmullRomSpline(
+        startHandle: const Offset(0.0, double.infinity),
+        const <Offset>[Offset.zero, Offset.zero, Offset.zero, Offset.zero],
+      ).generateSamples();
+    }, throwsAssertionError);
+    expect(() {
+      CatmullRomSpline(
+        endHandle: const Offset(0.0, double.infinity),
+        const <Offset>[Offset.zero, Offset.zero, Offset.zero, Offset.zero],
+      ).generateSamples();
+    }, throwsAssertionError);
   });
 
   test('CatmullRomSpline interpolates values properly when precomputed', () {
@@ -353,6 +375,24 @@ void main() {
     expect(() {
       CatmullRomSpline.precompute(const <Offset>[Offset.zero, Offset.zero, Offset.zero, Offset.zero], tension: 2.0);
     }, throwsAssertionError);
+    expect(() {
+      CatmullRomSpline.precompute(const <Offset>[Offset(double.infinity, 0.0), Offset.zero, Offset.zero, Offset.zero]);
+    }, throwsAssertionError);
+    expect(() {
+      CatmullRomSpline.precompute(const <Offset>[Offset(0.0, double.infinity), Offset.zero, Offset.zero, Offset.zero]);
+    }, throwsAssertionError);
+    expect(() {
+      CatmullRomSpline.precompute(
+        startHandle: const Offset(0.0, double.infinity),
+        const <Offset>[Offset.zero, Offset.zero, Offset.zero, Offset.zero],
+      );
+    }, throwsAssertionError);
+    expect(() {
+      CatmullRomSpline.precompute(
+        endHandle: const Offset(0.0, double.infinity),
+        const <Offset>[Offset.zero, Offset.zero, Offset.zero, Offset.zero],
+      );
+    }, throwsAssertionError);
   });
 
   test('CatmullRomCurve interpolates given points correctly', () {