housekeeping

.github/workflows/test.yaml

@@ -0,0 +1,23 @@
+name: test
+on:
+  pull_request:
+    types: [opened, synchronize]
+  push:
+    branches: [ master, main ]
+jobs:
+  test:
+    name: test
+    runs-on: ubuntu-latest
+    container:
+      image:  google/dart:latest
+    steps:
+      - name: set up repository
+        uses: actions/checkout@v2
+      - name: install deps
+        run: pub get
+      - name: analyzer
+        run: dartanalyzer --fatal-warnings --fatal-infos .
+      - name: clone spec
+        run: |
+          git clone https://github.com/mustache/spec.git test/spec
+          dart test/all.dart

analysis_options.yaml

@@ -1,5 +1,29 @@
+analyzer:
+  language:
+    strict-casts: true
+    strict-inference: true
+    strict-raw-types: true
 linter:
   rules:
-    unawaited_futures: true
-    curly_braces_in_flow_control_structures: true
-    avoid_catches_without_on_clauses: true
+    - unawaited_futures
+    - curly_braces_in_flow_control_structures
+    - avoid_catches_without_on_clauses
+    - avoid_empty_else
+    - empty_catches
+    - avoid_print
+    - prefer_const_constructors_in_immutables
+    - prefer_const_constructors
+    - prefer_const_declarations
+    - unnecessary_const
+    - prefer_final_fields
+    - prefer_final_locals
+    - prefer_null_aware_operators
+    - provide_deprecation_message
+    - unnecessary_new
+    - unnecessary_null_aware_assignments
+    - unnecessary_null_in_if_null_operators
+    - unnecessary_brace_in_string_interps
+    - unnecessary_overrides
+    - unnecessary_parenthesis
+    - unnecessary_statements
+    - valid_regexps

lib/mustache.dart

@@ -20,12 +20,12 @@ abstract class Template {
   /// [values] can be a combination of Map, List, String. Any non-String object
   /// will be converted using toString(). Null values will cause a
   /// [TemplateException], unless lenient module is enabled.
-  String renderString(values);
+  String renderString(dynamic values);
 
   /// [values] can be a combination of Map, List, String. Any non-String object
   /// will be converted using toString(). Null values will cause a
   /// [TemplateException], unless lenient module is enabled.
-  void render(values, StringSink sink);
+  void render(dynamic values, StringSink sink);
 }
 
 typedef PartialResolver = Template? Function(String);
@@ -43,7 +43,7 @@ abstract class LambdaContext {
 
   /// Render and directly output the current section tag. If provided, value
   /// will be added to the top of the context's stack.
-  void render({Object value});
+  void render({Object? value});
 
   /// Output a string. The output will not be html escaped, and will be written
   /// before the output returned from the lambda.

lib/src/ability.dart

@@ -0,0 +1,30 @@
+
+
+
+import 'package:mustache_template/src/lambda_context.dart';
+
+import 'package:mustache_template/mustache.dart' as m;
+
+mixin HasSource {
+  /// The template source.
+  String get source;
+}
+
+mixin Writable<T>{
+  T? get self;
+  void write(Object object);
+}
+
+mixin LambdaCtxWritable on m.LambdaContext implements Writable<LambdaContext> {
+  LambdaContext? get self => this is LambdaContext ? this as LambdaContext : null;
+  @override
+  void write(Object object) {
+    if(self == null){
+      throw UnimplementedError();
+    }else {
+      self as LambdaContext;
+      self!.checkClosedOrThrow();
+      self!.renderer.write(object);
+    }
+  }
+}

lib/src/lambda_context.dart

@@ -1,12 +1,14 @@
 import 'package:mustache_template/mustache.dart' as m;
+import 'package:mustache_template/src/ability.dart';
+import 'package:meta/meta.dart';
 
 import 'node.dart';
 import 'parser.dart' as parser;
 import 'renderer.dart';
 import 'template_exception.dart';
 
 /// Passed as an argument to a mustache lambda function.
-class LambdaContext implements m.LambdaContext {
+class LambdaContext extends m.LambdaContext with HasSource,LambdaCtxWritable {
   final Node _node;
   final Renderer _renderer;
   bool _closed = false;
@@ -21,6 +23,15 @@ class LambdaContext implements m.LambdaContext {
     if (_closed) throw _error('LambdaContext accessed outside of callback.');
   }
 
+  @internal
+  bool get isClosed => _closed;
+
+  @internal
+  Renderer get renderer => _renderer;
+
+  @internal
+  Node get node =>_node;
+
   TemplateException _error(String msg) {
     return TemplateException(
         msg, _renderer.templateName, _renderer.source, _node.start);
@@ -33,14 +44,14 @@ class LambdaContext implements m.LambdaContext {
       _error(
           'LambdaContext.renderString() can only be called on section tags.');
     }
-    var sink = StringBuffer();
+    final sink = StringBuffer();
     _renderSubtree(sink, value);
     return sink.toString();
   }
 
   void _renderSubtree(StringSink sink, Object? value) {
-    var renderer = Renderer.subtree(_renderer, sink);
-    var section = _node as SectionNode;
+    final renderer = Renderer.subtree(_renderer, sink);
+    final section = _node as SectionNode;
     if (value != null) renderer.push(value);
     renderer.render(section.children);
   }
@@ -54,45 +65,41 @@ class LambdaContext implements m.LambdaContext {
     _renderSubtree(_renderer.sink, value);
   }
 
-  @override
-  void write(Object object) {
-    _checkClosed();
-    _renderer.write(object);
-  }
+  @internal
+  void checkClosedOrThrow() => _checkClosed();
 
   @override
   String get source {
     _checkClosed();
 
-    if (_node is! SectionNode) return '';
-
-    var node = _node as SectionNode;
-    var nodes = node.children;
-    if (nodes.isEmpty) return '';
-
-    if (nodes.length == 1 && nodes.first is TextNode) {
-      return (nodes.single as TextNode).text;
-    }
-
-    return _renderer.source.substring(node.contentStart, node.contentEnd);
+    if(_node is SectionNode) {
+     final node = _node as SectionNode;
+      if(node.children.isEmpty){
+       return '';
+      } else {
+        if(node.children.length == 1 && node.children.first is TextNode) {
+          return (node.children.single as TextNode).text;
+        } else {
+          return _renderer.source.substring(node.contentStart, node.contentEnd);
+        }
+      }
+    }else{
+      return '';
+     }
   }
 
   @override
   String renderSource(String source, {Object? value}) {
     _checkClosed();
-    var sink = StringBuffer();
+    final sink = StringBuffer();
 
     // Lambdas used for sections should parse with the current delimiters.
-    var delimiters = '{{ }}';
-    if (_node is SectionNode) {
-      var node = _node as SectionNode;
-      delimiters = node.delimiters;
-    }
+    final delimiters =  _node is SectionNode ? (_node as SectionNode).delimiters : '{{ }}';
 
-    var nodes = parser.parse(
+    final nodes = parser.parse(
         source, _renderer.lenient, _renderer.templateName, delimiters);
 
-    var renderer =
+    final renderer =
         Renderer.lambda(_renderer, source, _renderer.indent, sink, delimiters);
 
     if (value != null) renderer.push(value);

lib/src/node.dart

@@ -1,5 +1,5 @@
 abstract class Node {
-  Node(this.start, this.end);
+  const Node(this.start, this.end);
 
   // The offset of the start of the token in the file. Unless this is a section
   // or inverse section, then this stores the start of the content of the
@@ -19,15 +19,15 @@ abstract class Visitor {
 }
 
 class TextNode extends Node {
-  TextNode(this.text, int start, int end) : super(start, end);
+  const TextNode(this.text, int start, int end) : super(start, end);
 
   final String text;
 
   @override
   String toString() => '(TextNode "$_debugText" $start $end)';
 
   String get _debugText {
-    var t = text.replaceAll('\n', '\\n');
+    final t = text.replaceAll('\n', '\\n');
     return t.length < 50 ? t : t.substring(0, 48) + '...';
   }
 
@@ -36,7 +36,7 @@ class TextNode extends Node {
 }
 
 class VariableNode extends Node {
-  VariableNode(this.name, int start, int end, {this.escape = true})
+  const VariableNode(this.name, int start, int end, {this.escape = true})
       : super(start, end);
 
   final String name;
@@ -75,7 +75,7 @@ class SectionNode extends Node {
 }
 
 class PartialNode extends Node {
-  PartialNode(this.name, int start, int end, this.indent) : super(start, end);
+  const PartialNode(this.name, int start, int end, this.indent) : super(start, end);
 
   final String name;