replace asserts for semantic labels with lints (#3483)

cw_custom_lints/lib/main.dart

@@ -1,6 +1,8 @@
 import "package:analysis_server_plugin/plugin.dart";
 import "package:analysis_server_plugin/registry.dart";
 import "package:cw_custom_lints/http_force_proxy/http_force_proxy_rule.dart";
+import "package:cw_custom_lints/modal_top_bar_semantics/modal_top_bar_semantics_rule.dart";
+import "package:cw_custom_lints/modern_button_semantics/modern_button_semantics_rule.dart";
 import "package:cw_custom_lints/print_verbose/print_verbose_fix.dart";
 import "package:cw_custom_lints/print_verbose/print_verbose_rule.dart";
 import "package:cw_custom_lints/restricted_imports/restricted_imports_rule.dart";
@@ -16,6 +18,8 @@ class CwCustomLintsPlugin extends Plugin {
     registry.registerWarningRule(PrintVerboseRule());
     registry.registerWarningRule(RestrictedImportsRule());
     registry.registerWarningRule(HttpForceProxyRule());
+    registry.registerWarningRule(ModernButtonSemanticsRule());
+    registry.registerWarningRule(ModalTopBarSemanticsRule());
 
     registry.registerFixForRule(PrintVerboseRule.code, ReplaceWithPrintV.new);
   }

cw_custom_lints/lib/modal_top_bar_semantics/modal_top_bar_semantics_rule.dart

@@ -0,0 +1,69 @@
+import "package:analyzer/analysis_rule/analysis_rule.dart";
+import "package:analyzer/analysis_rule/rule_context.dart";
+import "package:analyzer/analysis_rule/rule_visitor_registry.dart";
+import "package:analyzer/dart/ast/ast.dart";
+import "package:analyzer/dart/ast/visitor.dart";
+import "package:analyzer/error/error.dart";
+import "package:cw_custom_lints/utils/widget_arguments.dart";
+
+class ModalTopBarSemanticsRule extends AnalysisRule {
+  ModalTopBarSemanticsRule()
+    : super(
+        name: "require_modal_top_bar_semantics",
+        description:
+            "ModalTopBar icons need a semantic label, because the icon alone does not say whether it closes the modal, goes back or does something else.",
+      );
+
+  static const LintCode code = LintCode(
+    "require_modal_top_bar_semantics",
+    "ModalTopBar was given a {0} without a {1}, so screen readers have nothing to announce.",
+    correctionMessage: "Pass a localized {1} next to the {0}.",
+    severity: DiagnosticSeverity.WARNING,
+  );
+
+  static const _iconSemanticLabels = {
+    "leadingIcon": "leadingSemanticLabel",
+    "trailingIcon": "trailingSemanticLabel",
+  };
+
+  @override
+  LintCode get diagnosticCode => code;
+
+  @override
+  void registerNodeProcessors(RuleVisitorRegistry registry, RuleContext context) =>
+      registry.addInstanceCreationExpression(this, _Visitor(this));
+}
+
+class _Visitor extends SimpleAstVisitor<void> {
+  _Visitor(this.rule);
+
+  final AnalysisRule rule;
+
+  @override
+  void visitInstanceCreationExpression(InstanceCreationExpression node) {
+    if (!isCakeWalletWidget(node.constructorName, "ModalTopBar")) {
+      return;
+    }
+
+    for (final slot in ModalTopBarSemanticsRule._iconSemanticLabels.entries) {
+      _checkSlot(node.argumentList, iconName: slot.key, semanticLabelName: slot.value);
+    }
+  }
+
+  void _checkSlot(
+    ArgumentList argumentList, {
+    required String iconName,
+    required String semanticLabelName,
+  }) {
+    final icon = namedArgument(argumentList, iconName);
+    if (icon == null || icon.argumentExpression is NullLiteral) {
+      return;
+    }
+
+    if (!isMissingOrEmptyText(namedArgumentExpression(argumentList, semanticLabelName))) {
+      return;
+    }
+
+    rule.reportAtToken(icon.name, arguments: [iconName, semanticLabelName]);
+  }
+}

cw_custom_lints/lib/modern_button_semantics/modern_button_semantics_rule.dart

@@ -0,0 +1,56 @@
+import "package:analyzer/analysis_rule/analysis_rule.dart";
+import "package:analyzer/analysis_rule/rule_context.dart";
+import "package:analyzer/analysis_rule/rule_visitor_registry.dart";
+import "package:analyzer/dart/ast/ast.dart";
+import "package:analyzer/dart/ast/visitor.dart";
+import "package:analyzer/error/error.dart";
+import "package:cw_custom_lints/utils/widget_arguments.dart";
+
+class ModernButtonSemanticsRule extends AnalysisRule {
+  ModernButtonSemanticsRule()
+    : super(
+        name: "require_modern_button_semantics",
+        description:
+            "ModernButton needs a semanticLabel when it has no visible label, otherwise screen readers announce an unnamed button.",
+      );
+
+  static const LintCode code = LintCode(
+    "require_modern_button_semantics",
+    "ModernButton has no visible label, so screen readers have nothing to announce.",
+    correctionMessage: "Pass a localized semanticLabel, or a non-empty label.",
+    severity: DiagnosticSeverity.WARNING,
+  );
+
+  @override
+  LintCode get diagnosticCode => code;
+
+  @override
+  void registerNodeProcessors(RuleVisitorRegistry registry, RuleContext context) =>
+      registry.addInstanceCreationExpression(this, _Visitor(this));
+}
+
+class _Visitor extends SimpleAstVisitor<void> {
+  _Visitor(this.rule);
+
+  final AnalysisRule rule;
+
+  @override
+  void visitInstanceCreationExpression(InstanceCreationExpression node) {
+    final constructorName = node.constructorName;
+    if (!isCakeWalletWidget(constructorName, "ModernButton")) {
+      return;
+    }
+
+    final argumentList = node.argumentList;
+    final hasLabel = !isMissingOrEmptyText(namedArgumentExpression(argumentList, "label"));
+    final hasSemanticLabel = !isMissingOrEmptyText(
+      namedArgumentExpression(argumentList, "semanticLabel"),
+    );
+
+    if (hasLabel || hasSemanticLabel) {
+      return;
+    }
+
+    rule.reportAtNode(constructorName);
+  }
+}

cw_custom_lints/lib/no_bare_catch/no_bare_catch_rule.dart

@@ -0,0 +1,51 @@
+import "package:analyzer/analysis_rule/analysis_rule.dart";
+import "package:analyzer/analysis_rule/rule_context.dart";
+import "package:analyzer/analysis_rule/rule_visitor_registry.dart";
+import "package:analyzer/dart/ast/ast.dart";
+import "package:analyzer/dart/ast/visitor.dart";
+import "package:analyzer/error/error.dart";
+
+class NoBareCatchRule extends AnalysisRule {
+  NoBareCatchRule()
+    : super(
+        name: "no_bare_catch",
+        description: "please specify the exception class to catch (on SomeException catch (e))",
+      );
+
+  static const LintCode code = LintCode(
+    "no_bare_catch",
+    "please specify the exception class to catch (on SomeException catch (e))",
+    severity: DiagnosticSeverity.WARNING,
+  );
+
+  @override
+  LintCode get diagnosticCode => code;
+
+  @override
+  void registerNodeProcessors(RuleVisitorRegistry registry, RuleContext context) {
+    registry.addCatchClause(this, _Visitor(this));
+  }
+}
+
+class _Visitor extends SimpleAstVisitor<void> {
+  _Visitor(this.rule);
+
+  final AnalysisRule rule;
+
+  @override
+  void visitCatchClause(CatchClause node) {
+    if (node.exceptionType != null) {
+      return;
+    }
+
+    final tryStatement = node.parent;
+    if (tryStatement is TryStatement) {
+      final precedingClauses = tryStatement.catchClauses.takeWhile((clause) => clause != node);
+      if (precedingClauses.any((clause) => clause.exceptionType != null)) {
+        return;
+      }
+    }
+
+    rule.reportAtNode(node);
+  }
+}

cw_custom_lints/lib/utils/widget_arguments.dart

@@ -0,0 +1,39 @@
+import "package:analyzer/dart/ast/ast.dart";
+
+bool isCakeWalletWidget(ConstructorName constructorName, String className) {
+  final element = constructorName.type.element;
+  if (element == null || element.name != className) {
+    return false;
+  }
+
+  final libraryUri = element.library?.uri;
+  if (libraryUri == null || libraryUri.scheme != "package") {
+    return false;
+  }
+
+  final segments = libraryUri.pathSegments;
+  return segments.isNotEmpty && segments.first == "cake_wallet";
+}
+
+NamedArgument? namedArgument(ArgumentList argumentList, String name) {
+  for (final argument in argumentList.arguments) {
+    if (argument is NamedArgument && argument.name.lexeme == name) {
+      return argument;
+    }
+  }
+
+  return null;
+}
+
+Expression? namedArgumentExpression(ArgumentList argumentList, String name) =>
+    namedArgument(argumentList, name)?.argumentExpression;
+
+// passed null or ""
+// does NOT work if a runtime expression evaluates to an empty string or null
+bool isMissingOrEmptyText(Expression? expression) {
+  if (expression == null || expression is NullLiteral) {
+    return true;
+  }
+
+  return expression is StringLiteral && (expression.stringValue?.isEmpty ?? false);
+}

lib/new-ui/widgets/modern_button.dart

@@ -28,9 +28,7 @@ class ModernButton extends StatelessWidget {
       this.backgroundColor,
       this.label,
       this.semanticLabel})
-      : svgPath = null,
-        assert(semanticLabel != null || (label != null && label != ""),
-            "ModernButton needs a semanticLabel when it has no visible label");
+      : svgPath = null;
 
   const ModernButton.svg(
       {super.key,
@@ -42,9 +40,7 @@ class ModernButton extends StatelessWidget {
       this.backgroundColor,
       this.label,
       this.semanticLabel})
-      : icon = null,
-        assert(semanticLabel != null || (label != null && label != ""),
-            "ModernButton needs a semanticLabel when it has no visible label");
+      : icon = null;
 
   @override
   Widget build(BuildContext context) {

lib/new-ui/widgets/receive_page/receive_top_bar.dart

@@ -16,12 +16,7 @@ class ModalTopBar extends StatelessWidget {
       this.leadingWidget,
       this.trailingWidget,
       this.leadingSemanticLabel,
-      this.trailingSemanticLabel})
-      : assert(leadingIcon == null || (leadingSemanticLabel != null && leadingSemanticLabel != ""),
-            "leadingIcon requires a non-empty leadingSemanticLabel"),
-        assert(
-            trailingIcon == null || (trailingSemanticLabel != null && trailingSemanticLabel != ""),
-            "trailingIcon requires a non-empty trailingSemanticLabel") {
+      this.trailingSemanticLabel}) {
     if (leadingIcon != null && leadingWidget != null) {
       throw Exception("Cannot have both leadingIcon and leadingWidget");
     }