[cross_file] always set browser blob when constructing XFile from data (#8611)

This PR fixes a bug where files created with `XFile.fromData()` would ignore the provided bytes if the path is present, too.
Now if the bytes and the path are both provided, the content is read from the bytes directly.

Fixes flutter/flutter#163044

Author: navaronbracke

packages/cross_file/CHANGELOG.md

@@ -1,5 +1,6 @@
-## NEXT
+## 0.3.5
 
+* Fixes a bug where the bytes of an XFile, that is created using the `XFile.fromData` constructor, are ignored on web.
 * Updates minimum supported SDK version to Flutter 3.29/Dart 3.7.
 
 ## 0.3.4+2

packages/cross_file/lib/src/types/html.dart

@@ -64,12 +64,8 @@ class XFile extends XFileBase {
        _lastModified = lastModified ?? DateTime.fromMillisecondsSinceEpoch(0),
        _name = name ?? '',
        super(path) {
-    if (path == null) {
-      _browserBlob = _createBlobFromBytes(bytes, mimeType);
-      _path = URL.createObjectURL(_browserBlob!);
-    } else {
-      _path = path;
-    }
+    _browserBlob = _createBlobFromBytes(bytes, mimeType);
+    _path = URL.createObjectURL(_browserBlob!);
   }
 
   // Initializes a Blob from a bunch of `bytes` and an optional `mimeType`.

packages/cross_file/lib/src/types/interface.dart

@@ -35,7 +35,10 @@ class XFile extends XFileBase {
     );
   }
 
-  /// Construct a CrossFile object from its data
+  /// Construct a CrossFile object from its data.
+  ///
+  /// On the web, the [path] is ignored if the [bytes] are provided,
+  /// as the underlying Blob URL is used as the path.
   XFile.fromData(
     Uint8List bytes, {
     String? mimeType,

packages/cross_file/pubspec.yaml

@@ -2,7 +2,7 @@ name: cross_file
 description: An abstraction to allow working with files across multiple platforms.
 repository: https://github.com/flutter/packages/tree/main/packages/cross_file
 issue_tracker: https://github.com/flutter/flutter/issues?q=is%3Aissue+is%3Aopen+label%3A%22p%3A+cross_file%22
-version: 0.3.4+2
+version: 0.3.5
 
 environment:
   sdk: ^3.7.0

packages/cross_file/test/x_file_html_test.dart

@@ -63,6 +63,24 @@ void main() {
     test('Stream can be sliced', () async {
       expect(await file.openRead(2, 5).first, equals(bytes.sublist(2, 5)));
     });
+
+    test('Prefers local bytes over path if both are provided', () async {
+      const String text = 'Hello World';
+      const String path = 'test/x_file_html_test.dart';
+
+      final XFile file = XFile.fromData(
+        utf8.encode(text),
+        path: path,
+        name: 'x_file_html_test.dart',
+        length: text.length,
+        mimeType: 'text/plain',
+        lastModified: DateTime.now(),
+      );
+
+      expect(file.path, isNot(equals(path)));
+      expect(file.path.startsWith('blob:'), isTrue);
+      expect(await file.readAsString(), equals(text));
+    });
   });
 
   group('Blob backend', () {