Improve name generation for indexed expressions

pkg/analysis_server/lib/src/services/correction/name_suggestion.dart

Index: pkg/analysis_server/lib/src/services/correction/name_suggestion.dart
diff --git a/pkg/analysis_server/lib/src/services/correction/name_suggestion.dart b/pkg/analysis_server/lib/src/services/correction/name_suggestion.dart
index 4c10fec3c1e5871c8a9068e9ebcb208ee36198db..b96d7cf0acd5927b78f3666859ce12fc1a275ac1 100644
--- a/pkg/analysis_server/lib/src/services/correction/name_suggestion.dart
+++ b/pkg/analysis_server/lib/src/services/correction/name_suggestion.dart
@@ -136,27 +136,49 @@ void _addSingleCharacterName(Set<String> excluded, Set<String> result, int c) {
 }
 
 String _getBaseNameFromExpression(Expression expression) {
-  String name = null;
-  // e as Type
   if (expression is AsExpression) {
-    AsExpression asExpression = expression as AsExpression;
-    expression = asExpression.expression;
+    return _getBaseNameFromExpression(expression.expression);
+  } else if (expression is ParenthesizedExpression) {
+    return _getBaseNameFromExpression(expression.expression);
   }
+  return _getBaseNameFromUnwrappedExpression(expression);
+}
+
+String _getBaseNameFromLocationInParent(Expression expression) {
+  // value in named expression
+  if (expression.parent is NamedExpression) {
+    NamedExpression namedExpression = expression.parent as NamedExpression;
+    if (namedExpression.expression == expression) {
+      return namedExpression.name.label.name;
+    }
+  }
+  // positional argument
+  {
+    ParameterElement parameter = expression.propagatedParameterElement;
+    if (parameter == null) {
+      parameter = expression.staticParameterElement;
+    }
+    if (parameter != null) {
+      return parameter.displayName;
+    }
+  }
+  // unknown
+  return null;
+}
+
+String _getBaseNameFromUnwrappedExpression(Expression expression) {
+  String name = null;
   // analyze expressions
   if (expression is SimpleIdentifier) {
-    SimpleIdentifier node = expression;
-    return node.name;
+    return expression.name;
   } else if (expression is PrefixedIdentifier) {
-    PrefixedIdentifier node = expression;
-    return node.identifier.name;
+    return expression.identifier.name;
   } else if (expression is PropertyAccess) {
-    PropertyAccess node = expression;
-    return node.propertyName.name;
+    return expression.propertyName.name;
   } else if (expression is MethodInvocation) {
     name = expression.methodName.name;
   } else if (expression is InstanceCreationExpression) {
-    InstanceCreationExpression creation = expression;
-    ConstructorName constructorName = creation.constructorName;
+    ConstructorName constructorName = expression.constructorName;
     TypeName typeName = constructorName.type;
     if (typeName != null) {
       Identifier typeNameIdentifier = typeName.name;
@@ -175,6 +197,13 @@ String _getBaseNameFromExpression(Expression expression) {
         return prefixed.prefix.name;
       }
     }
+  } else if (expression is IndexExpression) {
+    name = _getBaseNameFromExpression(expression.realTarget);
+    if (name.endsWith('es')) {
+      name = name.substring(0, name.length - 2);
+    } else if (name.endsWith('s')) {
+      name = name.substring(0, name.length - 1);
+    }
   }
   // strip known prefixes
   if (name != null) {
@@ -192,25 +221,3 @@ String _getBaseNameFromExpression(Expression expression) {
   // done
   return name;
 }
-
-String _getBaseNameFromLocationInParent(Expression expression) {
-  // value in named expression
-  if (expression.parent is NamedExpression) {
-    NamedExpression namedExpression = expression.parent as NamedExpression;
-    if (namedExpression.expression == expression) {
-      return namedExpression.name.label.name;
-    }
-  }
-  // positional argument
-  {
-    ParameterElement parameter = expression.propagatedParameterElement;
-    if (parameter == null) {
-      parameter = expression.staticParameterElement;
-    }
-    if (parameter != null) {
-      return parameter.displayName;
-    }
-  }
-  // unknown
-  return null;
-}