Remove use of dynamic

Adds guard clause to constrain refactoring action to the finite set of supported types.
rubberduck-vba · Dec 4, 2020 · 01de2f1 · 01de2f1
1 parent f5d2cd3
commit 01de2f1
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Showing 2 changed files with 26 additions and 6 deletions.
diff --git a/Rubberduck.Refactorings/ImplicitTypeToExplicit/ImplicitTypeToExplicitRefactoringAction.cs b/Rubberduck.Refactorings/ImplicitTypeToExplicit/ImplicitTypeToExplicitRefactoringAction.cs
@@ -1,7 +1,7 @@
-using System.Collections.Generic;
+using System;
+using System.Collections.Generic;
 using System.Linq;
 using Antlr4.Runtime;
-using Antlr4.Runtime.Tree;
 using Rubberduck.Parsing;
 using Rubberduck.Parsing.Grammar;
 using Rubberduck.Parsing.Rewriter;
@@ -27,10 +27,15 @@ public class ImplicitTypeToExplicitRefactoringAction : CodeOnlyRefactoringAction
 
         public override void Refactor(ImplicitTypeToExplicitModel model, IRewriteSession rewriteSession)
         {
-            ParserRuleContext identifierNode =
-                model.Target.Context is VBAParser.VariableSubStmtContext || model.Target.Context is VBAParser.ConstSubStmtContext || model.Target.Context is VBAParser.FunctionStmtContext
-                ? model.Target.Context.children[0]
-                : ((dynamic)model.Target.Context).unrestrictedIdentifier();
+            if (!(model.Target.Context is VBAParser.VariableSubStmtContext
+                    || model.Target.Context is VBAParser.ConstSubStmtContext
+                    || model.Target.Context is VBAParser.ArgContext))
+            {
+                throw new ArgumentException($"Invalid target {model.Target.IdentifierName}");
+            }
+
+            var identifierNode = model.Target.Context.GetChild<VBAParser.IdentifierContext>()
+                        ?? model.Target.Context.GetChild<VBAParser.UnrestrictedIdentifierContext>() as ParserRuleContext;
 
             var insertAfterTarget = model.Target.IsArray
                 ? model.Target.Context.Stop.TokenIndex

diff --git a/...efactoring/ImplicitTypeToExplicit/ImplicitTypeToExplicitRefactoringActionVariableTests.cs b/...efactoring/ImplicitTypeToExplicit/ImplicitTypeToExplicitRefactoringActionVariableTests.cs
@@ -3,6 +3,7 @@
 using Rubberduck.Refactorings.ImplicitTypeToExplicit;
 using Rubberduck.VBEditor.SafeComWrappers;
 using RubberduckTests.Mocks;
+using System;
 using System.Collections.Generic;
 
 namespace RubberduckTests.Refactoring.ImplicitTypeToExplicit
@@ -52,6 +53,20 @@ Dim var1
             StringAssert.Contains($"{targetName} As Variant", refactoredCode);
         }
 
+        [Test]
+        [Category("Refactorings")]
+        [Category(nameof(ImplicitTypeToExplicitRefactoringAction))]
+        public void InvalidTarget_ThrowsArgumentException()
+        {
+            var targetName = "Foo";
+            var inputCode =
+$@"Sub Foo()
+End Sub";
+
+            Assert.Throws<ArgumentException>( () => RefactoredCode(inputCode,
+                state => TestModel(state, (targetName, DeclarationType.Procedure), (model) => model)));
+        }
+
         [TestCase("var1 = 42", "Long", "Long")]
         [TestCase("var1 = 42.55", "Long", "Double")]
         [Category("Refactorings")]