Clean up the support matrix a bit, and what we do/don't test for acro…

…ss platforms.

melos.yaml

@@ -10,7 +10,8 @@ scripts:
   test:
     run: |
       melos run test:dart --no-select && \
-      melos run test:flutter --no-select
+      melos run test:flutter --no-select && \
+      melos run test:chrome --no-select
 
   test:node:
     run: melos run test:dart:node --no-select

packages/pmtiles/README.md

@@ -70,6 +70,21 @@ Future<int> main() async {
 
 ```
 
+## Support Matrix
+
+Some effort has been made to ensure this library works correctly on
+the native Dart VM, as well as when dart2js is used to compiled to
+JavaScript (e.g. for use with Node.js or Chrome). The following table
+shows the support matrix.
+
+| Feature | Dart VM | Node.js | Browsers (e.g Chrome) |
+| ------: | :-----: | :-----: | :-------------------: |
+|         | Native  | dart2js |        dart2js        |
+|    File |   Yes   |   No    |          No           |
+|    HTTP |   Yes   |   No    |          Yes          |
+
+If the library is used in an UnsupportedError exception will be thrown.
+
 ## Development
 
 Use `melos bootstrap` to install dependencies and link packages together.

packages/pmtiles/lib/src/io.dart

@@ -2,12 +2,10 @@ import 'dart:collection';
 import 'dart:math' as math;
 import 'package:http/http.dart';
 
-// Browsers don't support the File APIs
-export 'io_file.dart' if (dart.library.browser) 'io_file_fake.dart';
+// JS don't support the File APIs
+export 'io_file_fake.dart' if (dart.library.io) 'io_file.dart';
 
-// Node doesn't support the HTTP APIs
-// https://github.com/dart-lang/http/issues/1126
-export 'io_http.dart' if (dart.library.node) 'io_http_fake.dart';
+export 'io_http.dart';
 
 /// Simple interface so we can abstract reading from Files, or Http.
 abstract interface class ReadAt {

packages/pmtiles/lib/src/io_file_fake.dart

@@ -4,16 +4,16 @@ import 'io.dart';
 
 class FileAt implements ReadAt {
   FileAt(Object file) {
-    throw UnimplementedError('File APIs are not implemented on the web');
+    throw UnsupportedError('File APIs are not supported for dart2js');
   }
 
   @override
   Future<ByteStream> readAt(final int offset, final int length) async {
-    throw UnimplementedError('File APIs are not implemented on the web');
+    throw UnsupportedError('File APIs are not supported for dart2js');
   }
 
   @override
   Future<void> close() {
-    throw UnimplementedError('File APIs are not implemented on the web');
+    throw UnsupportedError('File APIs are not supported for dart2js');
   }
 }

packages/pmtiles/lib/src/io_http.dart

@@ -16,27 +16,43 @@ class HttpAt implements ReadAt {
 
   @override
   Future<ByteStream> readAt(int offset, int length) async {
-    final request = Request("GET", url);
+    try {
+      final request = Request("GET", url);
 
-    if (headers != null) request.headers.addAll(headers!);
-    request.headers[HttpHeaders.rangeHeader] =
-        'bytes=$offset-${offset + length - 1}';
+      if (headers != null) request.headers.addAll(headers!);
+      request.headers[HttpHeaders.rangeHeader] =
+          'bytes=$offset-${offset + length - 1}';
 
-    final response = await client.send(request);
+      final response = await client.send(request);
 
-    if (response.statusCode != 206) {
-      throw HttpException('Unexpected status code: ${response.statusCode}');
-    }
+      if (response.statusCode != 206) {
+        throw HttpException('Unexpected status code: ${response.statusCode}');
+      }
 
-    final responseLength = response.headers[HttpHeaders.contentLengthHeader];
-    if (responseLength != null && int.parse(responseLength) != length) {
-      throw HttpException(
-          'Unexpected Content-Length: $responseLength expected $length');
-    }
+      final responseLength = response.headers[HttpHeaders.contentLengthHeader];
+      if (responseLength != null && int.parse(responseLength) != length) {
+        throw HttpException(
+            'Unexpected Content-Length: $responseLength expected $length');
+      }
 
-    // TODO check Content-Range: bytes 0-1023/146515
+      // TODO check Content-Range: bytes 0-1023/146515
 
-    return response.stream;
+      return response.stream;
+    } catch (e) {
+      if (e
+          .toString()
+          .contains('Error: self.XMLHttpRequest is not a constructor')) {
+        // Node doesn't support the HTTP APIs
+        // https://github.com/dart-lang/http/issues/1126
+        //
+        // I don't know a better way to detect this, then after the error has
+        // happened. But hopefully this helps someone recongise what the odd
+        // error.
+        throw UnsupportedError('HTTP APIs are not supported for nodejs');
+      }
+
+      rethrow;
+    }
   }
 
   @override

packages/pmtiles/lib/src/io_http_fake.dart

@@ -5,16 +5,16 @@ import 'io.dart';
 class HttpAt implements ReadAt {
   HttpAt(Object client, Uri url,
       {Map<String, String>? headers, bool closeClient = false}) {
-    throw UnimplementedError('HTTP APIs are not implemented for nodejs');
+    throw UnsupportedError('HTTP APIs are not supported for nodejs');
   }
 
   @override
   Future<ByteStream> readAt(final int offset, final int length) async {
-    throw UnimplementedError('HTTP APIs are not implemented for nodejs');
+    throw UnsupportedError('HTTP APIs are not supported for nodejs');
   }
 
   @override
   Future<void> close() {
-    throw UnimplementedError('HTTP APIs are not implemented for nodejs');
+    throw UnsupportedError('HTTP APIs are not supported for nodejs');
   }
 }

packages/pmtiles/test/io_file_test.dart

@@ -1,4 +1,4 @@
-@TestOn('!browser') // Exclude from browsers because they doesn't support [File]
+@TestOn('!js') // Exclude from js because they doesn't support [File]
 
 import 'dart:io';
 import 'dart:typed_data';
@@ -8,12 +8,12 @@ import 'package:test/test.dart';
 
 void main() {
   group('FileAt', () {
-    late Directory directory;
+    Directory? directory;
     late File tempFile;
 
     setUp(() async {
       directory = await Directory.systemTemp.createTemp();
-      tempFile = File("${directory.path}/test_file");
+      tempFile = File("${directory!.path}/test_file");
 
       final f = await tempFile.create();
       await f.writeAsBytes(
@@ -22,7 +22,9 @@ void main() {
     });
 
     tearDown(() async {
-      await directory.delete(recursive: true);
+      if (directory != null) {
+        await directory!.delete(recursive: true);
+      }
     });
 
     final tests = <(int, int), List<int>>{

packages/pmtiles/test/support_matrix_test.dart

@@ -0,0 +1,27 @@
+import 'dart:io';
+
+import 'package:pmtiles/src/io.dart';
+import 'package:test/test.dart';
+import 'package:http/http.dart' as http;
+
+void main() {
+  test('File API is available', () {
+    expect(() => FileAt(File('/tmp/blah')), returnsNormally);
+  }, testOn: '!js');
+
+  test('File API is not available', () {
+    expect(() => FileAt(File('/tmp/blah')), throwsUnsupportedError);
+  }, testOn: 'js');
+
+  test('HTTP API is available', () {
+    final client = http.Client();
+    expect(() => HttpAt(client, Uri.parse("http://localhost/")).readAt(0, 1),
+        returnsNormally);
+  }, testOn: '!node');
+
+  test('HTTP API is not available', () {
+    final client = http.Client();
+    expect(() => HttpAt(client, Uri.parse("http://localhost/")).readAt(0, 1),
+        throwsUnsupportedError);
+  }, testOn: 'node');
+}

packages/pmtiles_tests/pubspec.yaml

@@ -23,7 +23,6 @@ dev_dependencies:
   path: ^1.8.3
   pmtiles: ^1.2.0
   stream_channel: ^2.1.2
-
   json_serializable: ^6.7.1
   json_annotation: ^4.8.1
   build_runner: ^2.4.8

packages/pmtiles_tests/test/archive_test.dart

@@ -362,7 +362,7 @@ void main() async {
       }
     }, onPlatform: {
       ...api == 'file'
-          ? {'browser': Skip('File API is not supported in browsers')}
+          ? {'js': Skip('File API is not supported in dart2js')}
           : {},
     }, timeout: Timeout(Duration(seconds: 90)));
   }

packages/pmtiles_tests/test/headers_test.dart

@@ -1,5 +1,5 @@
 // Exclude on browsers because it doesn't support the filesystem.
-@TestOn('!browser')
+@TestOn('!js')
 
 import 'package:pmtiles/pmtiles.dart';
 

packages/pmtiles_tests/test/simple_test.dart

@@ -79,6 +79,8 @@ void main() async {
     'invalid_v4.pmtiles': throwsA(isA<UnsupportedError>()),
     'test_fixture_1.pmtiles': throwsA(isA<UnsupportedError>()),
     'test_fixture_2.pmtiles': throwsA(isA<UnsupportedError>()),
+
+    // TODO Add a valid pmtiles file, that we can test against.
   };
 
   for (final e in fixtures.entries) {