refactor: add assertions, remove redundant constructor, unnecessary p…

…rivate field (#1832)

* remove private constructor from Bounds

* make SourceAttribution.onTap public since it gets provided by the user anyway

* add assertions

lib/src/layer/attribution_layer/rich/source.dart

@@ -7,19 +7,19 @@ import 'package:meta/meta.dart';
 /// Extended by [TextSourceAttribution] & [LogoSourceAttribution].
 @immutable
 sealed class SourceAttribution extends StatelessWidget {
-  const SourceAttribution._({super.key, VoidCallback? onTap}) : _onTap = onTap;
+  const SourceAttribution._({super.key, this.onTap});
 
-  final VoidCallback? _onTap;
+  final VoidCallback? onTap;
 
   Widget _render(BuildContext context);
 
   @override
   @nonVirtual
   Widget build(BuildContext context) {
-    if (_onTap == null) return _render(context);
+    if (onTap == null) return _render(context);
 
     return GestureDetector(
-      onTap: _onTap,
+      onTap: onTap,
       child: MouseRegion(
         cursor: SystemMouseCursors.click,
         child: _render(context),
@@ -33,7 +33,7 @@ sealed class SourceAttribution extends StatelessWidget {
 @immutable
 class TextSourceAttribution extends SourceAttribution {
   /// Default style used to display the [text], only when
-  /// [SourceAttribution._onTap] is not `null`
+  /// [SourceAttribution.onTap] is not `null`
   static const defaultLinkTextStyle =
       TextStyle(decoration: TextDecoration.underline);
 

lib/src/layer/polygon_layer/polygon_layer.dart

@@ -86,7 +86,10 @@ class PolygonLayer<R extends Object> extends StatefulWidget {
     this.polygonLabels = true,
     this.drawLabelsLast = false,
     this.hitNotifier,
-  });
+  }) : assert(
+          simplificationTolerance >= 0,
+          'simplificationTolerance cannot be negative: $simplificationTolerance',
+        );
 
   @override
   State<PolygonLayer<R>> createState() => _PolygonLayerState<R>();

lib/src/layer/polyline_layer/polyline_layer.dart

@@ -66,7 +66,10 @@ class PolylineLayer<R extends Object> extends StatefulWidget {
     this.simplificationTolerance = 0.4,
     this.hitNotifier,
     this.minimumHitbox = 10,
-  });
+  }) : assert(
+          simplificationTolerance >= 0,
+          'simplificationTolerance cannot be negative: $simplificationTolerance',
+        );
 
   @override
   State<PolylineLayer<R>> createState() => _PolylineLayerState<R>();

lib/src/misc/bounds.dart

@@ -30,15 +30,13 @@ class Bounds<T extends num> {
       minY = a.y;
       maxY = b.y;
     }
-    return Bounds._(Point<T>(minX, minY), Point<T>(maxX, maxY));
+    return Bounds.unsafe(Point<T>(minX, minY), Point<T>(maxX, maxY));
   }
 
   /// Create a [Bounds] instance **without** checking if [min] is actually the
   /// minimum and [max] is actually the maximum.
   const Bounds.unsafe(this.min, this.max);
 
-  const Bounds._(this.min, this.max);
-
   /// Create a [Bounds] as bounding box of a list of points.
   static Bounds<double> containing(Iterable<Point<double>> points) {
     var maxX = double.negativeInfinity;
@@ -53,13 +51,13 @@ class Bounds<T extends num> {
       minY = math.min(point.y, minY);
     }
 
-    return Bounds._(Point(minX, minY), Point(maxX, maxY));
+    return Bounds.unsafe(Point(minX, minY), Point(maxX, maxY));
   }
 
   /// Creates a new [Bounds] obtained by expanding the current ones with a new
   /// point.
   Bounds<T> extend(Point<T> point) {
-    return Bounds._(
+    return Bounds.unsafe(
       Point(math.min(point.x, min.x), math.min(point.y, min.y)),
       Point(math.max(point.x, max.x), math.max(point.y, max.y)),
     );
@@ -147,7 +145,7 @@ class Bounds<T extends num> {
     final bottomY = math.min(max.y, b.max.y);
 
     if (leftX <= rightX && topY <= bottomY) {
-      return Bounds._(Point(leftX, topY), Point(rightX, bottomY));
+      return Bounds.unsafe(Point(leftX, topY), Point(rightX, bottomY));
     }
 
     return null;