Keep only first assignment as declaration (#1989)

Author: andyleejordan

src/PowerShellEditorServices/Services/Symbols/ReferenceTable.cs

@@ -94,6 +94,15 @@ private AstVisitAction AddReference(SymbolReference symbol)
             _ => new ConcurrentBag<SymbolReference> { symbol },
             (_, existing) =>
             {
+                // Keep only the first variable encountered as a declaration marked as such. This
+                // keeps the first assignment without also counting every reassignment as a
+                // declaration (cleaning up e.g. Code's outline view).
+                if (symbol.Type is SymbolType.Variable && symbol.IsDeclaration
+                    && existing.Any(i => i.IsDeclaration))
+                {
+                    symbol = symbol with { IsDeclaration = false };
+                }
+
                 existing.Add(symbol);
                 return existing;
             });

test/PowerShellEditorServices.Test.Shared/References/SimpleFile.ps1

@@ -5,7 +5,7 @@ function My-Function ($myInput)
 
 $things = 4
 
-$things
+$things = 3
 
 My-Function $things
 

test/PowerShellEditorServices.Test/Language/SymbolsServiceTests.cs

@@ -263,7 +263,8 @@ public async Task FindsFunctionDefinitionInWorkspace()
         [Fact]
         public async Task FindsVariableDefinition()
         {
-            SymbolReference symbol = await GetDefinition(FindsVariableDefinitionData.SourceDetails).ConfigureAwait(true);
+            IEnumerable<SymbolReference> definitions = await GetDefinitions(FindsVariableDefinitionData.SourceDetails).ConfigureAwait(true);
+            SymbolReference symbol = Assert.Single(definitions); // Even though it's re-assigned
             Assert.Equal("var things", symbol.Id);
             Assert.Equal("$things", symbol.Name);
             Assert.Equal(SymbolType.Variable, symbol.Type);