Merge pull request #43574 from allisonchou/SuggestionModePatternKeywordCompletion

Enable suggestion mode for certain cases in C# 9 pattern keyword completion

src/EditorFeatures/CSharpTest/Completion/CompletionProviders/SuggestionModeCompletionProviderTests.cs

@@ -1101,6 +1101,240 @@ public static void ReproMethod(Goo goo)
             await VerifyNotBuilderAsync(markup);
         }
 
+        [WorkItem(42368, "https://github.com/dotnet/roslyn/issues/42368")]
+        [Fact, Trait(Traits.Feature, Traits.Features.Completion)]
+        public async Task TestInDeclarationPattern()
+        {
+            var markup = @"
+class C
+{
+    void M()
+    {
+        var e = new object();
+        if (e is int o$$)
+    }
+}";
+            await VerifyBuilderAsync(markup);
+        }
+
+        [WorkItem(42368, "https://github.com/dotnet/roslyn/issues/42368")]
+        [Fact, Trait(Traits.Feature, Traits.Features.Completion)]
+        public async Task TestInDeclarationPattern2()
+        {
+            var markup = @"
+class C
+{
+    void M()
+    {
+        var e = new object();
+        if (e is System.Collections.Generic.List<int> an$$)
+    }
+}";
+            await VerifyBuilderAsync(markup);
+        }
+
+        [WorkItem(42368, "https://github.com/dotnet/roslyn/issues/42368")]
+        [Fact, Trait(Traits.Feature, Traits.Features.Completion)]
+        public async Task TestInRecursivePattern()
+        {
+            var markup = @"
+class C
+{
+    int P { get; }
+
+    void M(C test)
+    {
+        if (test is { P: 1 } o$$)
+    }
+}";
+            await VerifyBuilderAsync(markup);
+        }
+
+        [WorkItem(42368, "https://github.com/dotnet/roslyn/issues/42368")]
+        [Fact, Trait(Traits.Feature, Traits.Features.Completion)]
+        public async Task TestInPropertyPattern()
+        {
+            var markup = @"
+class C
+{
+    int P { get; }
+
+    void M(C test)
+    {
+        if (test is { P: int o$$ })
+    }
+}";
+            await VerifyBuilderAsync(markup);
+        }
+
+        [WorkItem(42368, "https://github.com/dotnet/roslyn/issues/42368")]
+        [Fact, Trait(Traits.Feature, Traits.Features.Completion)]
+        public async Task TestInAndPattern()
+        {
+            var markup = @"
+class C
+{
+    void M()
+    {
+        var e = new object();
+        if (e is 1 and int a$$)
+    }
+}";
+            await VerifyBuilderAsync(markup);
+        }
+
+        [WorkItem(42368, "https://github.com/dotnet/roslyn/issues/42368")]
+        [Fact, Trait(Traits.Feature, Traits.Features.Completion)]
+        public async Task TestInAndOrPattern()
+        {
+            var markup = @"
+class C
+{
+    void M()
+    {
+        var e = new object();
+        if (e is (int or 1) and int a$$)
+    }
+}";
+            await VerifyBuilderAsync(markup);
+        }
+
+        [WorkItem(42368, "https://github.com/dotnet/roslyn/issues/42368")]
+        [Fact, Trait(Traits.Feature, Traits.Features.Completion)]
+        public async Task TestInSwitchStatement()
+        {
+            var markup = @"
+class C
+{
+    void M()
+    {
+        var e = new object();
+        switch (e)
+        {
+            case int o$$
+        }
+    }
+}";
+            await VerifyBuilderAsync(markup);
+        }
+
+        [WorkItem(42368, "https://github.com/dotnet/roslyn/issues/42368")]
+        [Fact, Trait(Traits.Feature, Traits.Features.Completion)]
+        public async Task TestInSwitchExpression()
+        {
+            var markup = @"
+class C
+{
+    void M()
+    {
+        var e = new object();
+        var result = e switch
+        {
+            int o$$
+        }
+    }
+}";
+            await VerifyBuilderAsync(markup);
+        }
+
+        [WorkItem(42368, "https://github.com/dotnet/roslyn/issues/42368")]
+        [Fact, Trait(Traits.Feature, Traits.Features.Completion)]
+        public async Task TestMissingInNotPattern_Declaration()
+        {
+            var markup = @"
+class C
+{
+    void M()
+    {
+        var e = new object();
+        if (e is not int o$$)
+    }
+}";
+            await VerifyNotBuilderAsync(markup);
+        }
+
+        [WorkItem(42368, "https://github.com/dotnet/roslyn/issues/42368")]
+        [Fact, Trait(Traits.Feature, Traits.Features.Completion)]
+        public async Task TestMissingInNotPattern_Declaration2()
+        {
+            var markup = @"
+class C
+{
+    void M()
+    {
+        var e = new object();
+        if (e is not (1 and int o$$))
+    }
+}";
+            await VerifyNotBuilderAsync(markup);
+        }
+
+        [WorkItem(42368, "https://github.com/dotnet/roslyn/issues/42368")]
+        [Fact, Trait(Traits.Feature, Traits.Features.Completion)]
+        public async Task TestMissingInNotPattern_Recursive()
+        {
+            var markup = @"
+class C
+{
+    int P { get; }
+
+    void M(C test)
+    {
+        if (test is not { P: 1 } o$$)
+    }
+}";
+            await VerifyNotBuilderAsync(markup);
+        }
+
+        [WorkItem(42368, "https://github.com/dotnet/roslyn/issues/42368")]
+        [Fact, Trait(Traits.Feature, Traits.Features.Completion)]
+        public async Task TestMissingInOrPattern()
+        {
+            var markup = @"
+class C
+{
+    void M()
+    {
+        var e = new object();
+        if (e is 1 or int o$$)
+    }
+}";
+            await VerifyNotBuilderAsync(markup);
+        }
+
+        [WorkItem(42368, "https://github.com/dotnet/roslyn/issues/42368")]
+        [Fact, Trait(Traits.Feature, Traits.Features.Completion)]
+        public async Task TestMissingInAndOrPattern()
+        {
+            var markup = @"
+class C
+{
+    void M()
+    {
+        var e = new object();
+        if (e is 1 or int and int o$$)
+    }
+}";
+            await VerifyNotBuilderAsync(markup);
+        }
+
+        [WorkItem(42368, "https://github.com/dotnet/roslyn/issues/42368")]
+        [Fact, Trait(Traits.Feature, Traits.Features.Completion)]
+        public async Task TestMissingInRecursiveOrPattern()
+        {
+            var markup = @"
+class C
+{
+    int P { get; }
+
+    void M(C test)
+    {
+        if (test is null or { P: 1 } o$$)
+    }
+}";
+            await VerifyNotBuilderAsync(markup);
+        }
+
         private async Task VerifyNotBuilderAsync(string markup)
             => await VerifyWorkerAsync(markup, isBuilder: false);
 

src/EditorFeatures/CSharpTest2/Recommendations/AndKeywordRecommenderTests.cs

@@ -92,6 +92,19 @@ void M()
         if (e is System.Collections.Generic.List<int> $$");
         }
 
+        [Fact, Trait(Traits.Feature, Traits.Features.KeywordRecommending)]
+        public async Task TestAfterRecursivePattern()
+        {
+            await VerifyKeywordAsync(
+@"class C
+{
+    int P { get; }
+
+    void M(C test)
+    {
+        if (test is { P: 1 } $$");
+        }
+
         [Fact, Trait(Traits.Feature, Traits.Features.KeywordRecommending)]
         public async Task TestInsideSubpattern()
         {

src/EditorFeatures/CSharpTest2/Recommendations/OrKeywordRecommenderTests.cs

@@ -92,6 +92,19 @@ void M()
         if (e is System.Collections.Generic.List<int> $$");
         }
 
+        [Fact, Trait(Traits.Feature, Traits.Features.KeywordRecommending)]
+        public async Task TestAfterRecursivePattern()
+        {
+            await VerifyKeywordAsync(
+@"class C
+{
+    int P { get; }
+
+    void M(C test)
+    {
+        if (test is { P: 1 } $$");
+        }
+
         [Fact, Trait(Traits.Feature, Traits.Features.KeywordRecommending)]
         public async Task TestInsideSubpattern()
         {

src/Features/CSharp/Portable/CSharpFeaturesResources.resx

@@ -156,6 +156,12 @@
   <data name="Autoselect_disabled_due_to_possible_tuple_type_element_creation" xml:space="preserve">
     <value>Autoselect disabled due to possible tuple type element creation.</value>
   </data>
+  <data name="pattern_variable" xml:space="preserve">
+    <value>&lt;pattern variable&gt;</value>
+  </data>
+  <data name="Autoselect_disabled_due_to_potential_pattern_variable_declaration" xml:space="preserve">
+    <value>Autoselect disabled due to potential pattern variable declaration.</value>
+  </data>
   <data name="range_variable" xml:space="preserve">
     <value>&lt;range variable&gt;</value>
   </data>

src/Features/CSharp/Portable/Completion/SuggestionMode/CSharpSuggestionModeCompletionProvider.cs

@@ -60,6 +60,10 @@ public CSharpSuggestionModeCompletionProvider()
                 {
                     return CreateSuggestionModeItem(CSharpFeaturesResources.member_name, CSharpFeaturesResources.Autoselect_disabled_due_to_possible_explicitly_named_anonymous_type_member_creation);
                 }
+                else if (IsPotentialPatternVariableDeclaration(tree.FindTokenOnLeftOfPosition(position, cancellationToken)))
+                {
+                    return CreateSuggestionModeItem(CSharpFeaturesResources.pattern_variable, CSharpFeaturesResources.Autoselect_disabled_due_to_potential_pattern_variable_declaration);
+                }
                 else if (token.IsPreProcessorExpressionContext())
                 {
                     return CreateEmptySuggestionModeItem();
@@ -198,5 +202,40 @@ private ITypeSymbol GetDelegateType(TypeInferenceInfo typeInferenceInfo, Compila
 
             return typeSymbol.GetDelegateType(compilation);
         }
+
+        private bool IsPotentialPatternVariableDeclaration(SyntaxToken token)
+        {
+            var patternSyntax = token.GetAncestor<PatternSyntax>();
+            if (patternSyntax == null)
+            {
+                return false;
+            }
+
+            for (var current = patternSyntax; current != null; current = current.Parent as PatternSyntax)
+            {
+                // Patterns containing 'or' cannot contain valid variable declarations, e.g. 'e is 1 or int $$'
+                if (current.IsKind(SyntaxKind.OrPattern))
+                {
+                    return false;
+                }
+
+                // Patterns containing 'not' cannot be valid variable declarations, e.g. 'e is not int $$' and 'e is not (1 and int $$)'
+                if (current.IsKind(SyntaxKind.NotPattern))
+                {
+                    return false;
+                }
+            }
+
+            // e is int o$$
+            // e is { P: 1 } o$$
+            var lastTokenInPattern = patternSyntax.GetLastToken();
+            if (lastTokenInPattern.Parent is SingleVariableDesignationSyntax variableDesignationSyntax &&
+                token.Parent == variableDesignationSyntax)
+            {
+                return patternSyntax is DeclarationPatternSyntax || patternSyntax is RecursivePatternSyntax;
+            }
+
+            return false;
+        }
     }
 }

src/Features/CSharp/Portable/xlf/CSharpFeaturesResources.cs.xlf

@@ -77,6 +77,11 @@
         <target state="new">Assign to '{0}'</target>
         <note />
       </trans-unit>
+      <trans-unit id="Autoselect_disabled_due_to_potential_pattern_variable_declaration">
+        <source>Autoselect disabled due to potential pattern variable declaration.</source>
+        <target state="new">Autoselect disabled due to potential pattern variable declaration.</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Compare_to_0">
         <source>Compare to '{0}'</source>
         <target state="new">Compare to '{0}'</target>
@@ -237,6 +242,11 @@
         <target state="translated">Automatický výběr je zakázaný kvůli možnému vytvoření elementu typu řazená kolekce členů.</target>
         <note />
       </trans-unit>
+      <trans-unit id="pattern_variable">
+        <source>&lt;pattern variable&gt;</source>
+        <target state="new">&lt;pattern variable&gt;</target>
+        <note />
+      </trans-unit>
       <trans-unit id="range_variable">
         <source>&lt;range variable&gt;</source>
         <target state="translated">&lt;proměnná rozsahu&gt;</target>

src/Features/CSharp/Portable/xlf/CSharpFeaturesResources.de.xlf

@@ -77,6 +77,11 @@
         <target state="new">Assign to '{0}'</target>
         <note />
       </trans-unit>
+      <trans-unit id="Autoselect_disabled_due_to_potential_pattern_variable_declaration">
+        <source>Autoselect disabled due to potential pattern variable declaration.</source>
+        <target state="new">Autoselect disabled due to potential pattern variable declaration.</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Compare_to_0">
         <source>Compare to '{0}'</source>
         <target state="new">Compare to '{0}'</target>
@@ -237,6 +242,11 @@
         <target state="translated">Die automatische Auswahl wurde aufgrund einer möglichen Tupeltyp-Elementerstellung deaktiviert.</target>
         <note />
       </trans-unit>
+      <trans-unit id="pattern_variable">
+        <source>&lt;pattern variable&gt;</source>
+        <target state="new">&lt;pattern variable&gt;</target>
+        <note />
+      </trans-unit>
       <trans-unit id="range_variable">
         <source>&lt;range variable&gt;</source>
         <target state="translated">&lt;Bereichsvariable&gt;</target>

src/Features/CSharp/Portable/xlf/CSharpFeaturesResources.es.xlf

@@ -77,6 +77,11 @@
         <target state="new">Assign to '{0}'</target>
         <note />
       </trans-unit>
+      <trans-unit id="Autoselect_disabled_due_to_potential_pattern_variable_declaration">
+        <source>Autoselect disabled due to potential pattern variable declaration.</source>
+        <target state="new">Autoselect disabled due to potential pattern variable declaration.</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Compare_to_0">
         <source>Compare to '{0}'</source>
         <target state="new">Compare to '{0}'</target>
@@ -237,6 +242,11 @@
         <target state="translated">La selección automática se deshabilitó debido a la posible creación de elementos de tipo de tupla.</target>
         <note />
       </trans-unit>
+      <trans-unit id="pattern_variable">
+        <source>&lt;pattern variable&gt;</source>
+        <target state="new">&lt;pattern variable&gt;</target>
+        <note />
+      </trans-unit>
       <trans-unit id="range_variable">
         <source>&lt;range variable&gt;</source>
         <target state="translated">&lt;variable de intervalo&gt;</target>

src/Features/CSharp/Portable/xlf/CSharpFeaturesResources.fr.xlf

@@ -77,6 +77,11 @@
         <target state="new">Assign to '{0}'</target>
         <note />
       </trans-unit>
+      <trans-unit id="Autoselect_disabled_due_to_potential_pattern_variable_declaration">
+        <source>Autoselect disabled due to potential pattern variable declaration.</source>
+        <target state="new">Autoselect disabled due to potential pattern variable declaration.</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Compare_to_0">
         <source>Compare to '{0}'</source>
         <target state="new">Compare to '{0}'</target>
@@ -237,6 +242,11 @@
         <target state="translated">Sélection automatique désactivée en raison de la création possible d'un élément de type tuple.</target>
         <note />
       </trans-unit>
+      <trans-unit id="pattern_variable">
+        <source>&lt;pattern variable&gt;</source>
+        <target state="new">&lt;pattern variable&gt;</target>
+        <note />
+      </trans-unit>
       <trans-unit id="range_variable">
         <source>&lt;range variable&gt;</source>
         <target state="translated">&lt;variable de plage&gt;</target>

src/Features/CSharp/Portable/xlf/CSharpFeaturesResources.it.xlf

@@ -77,6 +77,11 @@
         <target state="new">Assign to '{0}'</target>
         <note />
       </trans-unit>
+      <trans-unit id="Autoselect_disabled_due_to_potential_pattern_variable_declaration">
+        <source>Autoselect disabled due to potential pattern variable declaration.</source>
+        <target state="new">Autoselect disabled due to potential pattern variable declaration.</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Compare_to_0">
         <source>Compare to '{0}'</source>
         <target state="new">Compare to '{0}'</target>
@@ -237,6 +242,11 @@
         <target state="translated">La selezione automatica è disabilitata a causa della potenziale creazione di elementi di tipo tupla.</target>
         <note />
       </trans-unit>
+      <trans-unit id="pattern_variable">
+        <source>&lt;pattern variable&gt;</source>
+        <target state="new">&lt;pattern variable&gt;</target>
+        <note />
+      </trans-unit>
       <trans-unit id="range_variable">
         <source>&lt;range variable&gt;</source>
         <target state="translated">&lt;variabile di intervallo&gt;</target>

src/Features/CSharp/Portable/xlf/CSharpFeaturesResources.ja.xlf

@@ -77,6 +77,11 @@
         <target state="new">Assign to '{0}'</target>
         <note />
       </trans-unit>
+      <trans-unit id="Autoselect_disabled_due_to_potential_pattern_variable_declaration">
+        <source>Autoselect disabled due to potential pattern variable declaration.</source>
+        <target state="new">Autoselect disabled due to potential pattern variable declaration.</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Compare_to_0">
         <source>Compare to '{0}'</source>
         <target state="new">Compare to '{0}'</target>
@@ -237,6 +242,11 @@
         <target state="translated">タプル型の要素が作成された可能性があるため、自動選択は無効になっています。</target>
         <note />
       </trans-unit>
+      <trans-unit id="pattern_variable">
+        <source>&lt;pattern variable&gt;</source>
+        <target state="new">&lt;pattern variable&gt;</target>
+        <note />
+      </trans-unit>
       <trans-unit id="range_variable">
         <source>&lt;range variable&gt;</source>
         <target state="translated">&lt;範囲変数&gt;</target>

src/Features/CSharp/Portable/xlf/CSharpFeaturesResources.ko.xlf

@@ -77,6 +77,11 @@
         <target state="new">Assign to '{0}'</target>
         <note />
       </trans-unit>
+      <trans-unit id="Autoselect_disabled_due_to_potential_pattern_variable_declaration">
+        <source>Autoselect disabled due to potential pattern variable declaration.</source>
+        <target state="new">Autoselect disabled due to potential pattern variable declaration.</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Compare_to_0">
         <source>Compare to '{0}'</source>
         <target state="new">Compare to '{0}'</target>
@@ -237,6 +242,11 @@
         <target state="translated">가능한 튜플 형식 요소 만들기로 인해 자동 선택을 사용할 수 없습니다.</target>
         <note />
       </trans-unit>
+      <trans-unit id="pattern_variable">
+        <source>&lt;pattern variable&gt;</source>
+        <target state="new">&lt;pattern variable&gt;</target>
+        <note />
+      </trans-unit>
       <trans-unit id="range_variable">
         <source>&lt;range variable&gt;</source>
         <target state="translated">&lt;범위 변수&gt;</target>

src/Features/CSharp/Portable/xlf/CSharpFeaturesResources.pl.xlf

@@ -77,6 +77,11 @@
         <target state="new">Assign to '{0}'</target>
         <note />
       </trans-unit>
+      <trans-unit id="Autoselect_disabled_due_to_potential_pattern_variable_declaration">
+        <source>Autoselect disabled due to potential pattern variable declaration.</source>
+        <target state="new">Autoselect disabled due to potential pattern variable declaration.</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Compare_to_0">
         <source>Compare to '{0}'</source>
         <target state="new">Compare to '{0}'</target>
@@ -237,6 +242,11 @@
         <target state="translated">Funkcja automatycznego wyboru została wyłączona ze względu na prawdopodobne utworzenie elementu typu krotki.</target>
         <note />
       </trans-unit>
+      <trans-unit id="pattern_variable">
+        <source>&lt;pattern variable&gt;</source>
+        <target state="new">&lt;pattern variable&gt;</target>
+        <note />
+      </trans-unit>
       <trans-unit id="range_variable">
         <source>&lt;range variable&gt;</source>
         <target state="translated">&lt;zmienna zakresu&gt;</target>

src/Features/CSharp/Portable/xlf/CSharpFeaturesResources.pt-BR.xlf

@@ -77,6 +77,11 @@
         <target state="new">Assign to '{0}'</target>
         <note />
       </trans-unit>
+      <trans-unit id="Autoselect_disabled_due_to_potential_pattern_variable_declaration">
+        <source>Autoselect disabled due to potential pattern variable declaration.</source>
+        <target state="new">Autoselect disabled due to potential pattern variable declaration.</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Compare_to_0">
         <source>Compare to '{0}'</source>
         <target state="new">Compare to '{0}'</target>
@@ -237,6 +242,11 @@
         <target state="translated">Seleção automática desabilitada devido a uma possível criação de elemento do tipo tupla.</target>
         <note />
       </trans-unit>
+      <trans-unit id="pattern_variable">
+        <source>&lt;pattern variable&gt;</source>
+        <target state="new">&lt;pattern variable&gt;</target>
+        <note />
+      </trans-unit>
       <trans-unit id="range_variable">
         <source>&lt;range variable&gt;</source>
         <target state="translated">&lt;variável de intervalo&gt;</target>

src/Features/CSharp/Portable/xlf/CSharpFeaturesResources.ru.xlf

@@ -77,6 +77,11 @@
         <target state="new">Assign to '{0}'</target>
         <note />
       </trans-unit>
+      <trans-unit id="Autoselect_disabled_due_to_potential_pattern_variable_declaration">
+        <source>Autoselect disabled due to potential pattern variable declaration.</source>
+        <target state="new">Autoselect disabled due to potential pattern variable declaration.</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Compare_to_0">
         <source>Compare to '{0}'</source>
         <target state="new">Compare to '{0}'</target>
@@ -237,6 +242,11 @@
         <target state="translated">Автовыбор отключен из-за возможного создания элемента типа кортежа.</target>
         <note />
       </trans-unit>
+      <trans-unit id="pattern_variable">
+        <source>&lt;pattern variable&gt;</source>
+        <target state="new">&lt;pattern variable&gt;</target>
+        <note />
+      </trans-unit>
       <trans-unit id="range_variable">
         <source>&lt;range variable&gt;</source>
         <target state="translated">&lt;переменная диапазона&gt;</target>

src/Features/CSharp/Portable/xlf/CSharpFeaturesResources.tr.xlf

@@ -77,6 +77,11 @@
         <target state="new">Assign to '{0}'</target>
         <note />
       </trans-unit>
+      <trans-unit id="Autoselect_disabled_due_to_potential_pattern_variable_declaration">
+        <source>Autoselect disabled due to potential pattern variable declaration.</source>
+        <target state="new">Autoselect disabled due to potential pattern variable declaration.</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Compare_to_0">
         <source>Compare to '{0}'</source>
         <target state="new">Compare to '{0}'</target>
@@ -237,6 +242,11 @@
         <target state="translated">Olası demet türü öğe oluşturma işleminden dolayı Otomatik seçim devre dışı bırakıldı.</target>
         <note />
       </trans-unit>
+      <trans-unit id="pattern_variable">
+        <source>&lt;pattern variable&gt;</source>
+        <target state="new">&lt;pattern variable&gt;</target>
+        <note />
+      </trans-unit>
       <trans-unit id="range_variable">
         <source>&lt;range variable&gt;</source>
         <target state="translated">&lt; Aralık değişkeni &gt;</target>

src/Features/CSharp/Portable/xlf/CSharpFeaturesResources.zh-Hans.xlf

@@ -77,6 +77,11 @@
         <target state="new">Assign to '{0}'</target>
         <note />
       </trans-unit>
+      <trans-unit id="Autoselect_disabled_due_to_potential_pattern_variable_declaration">
+        <source>Autoselect disabled due to potential pattern variable declaration.</source>
+        <target state="new">Autoselect disabled due to potential pattern variable declaration.</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Compare_to_0">
         <source>Compare to '{0}'</source>
         <target state="new">Compare to '{0}'</target>
@@ -237,6 +242,11 @@
         <target state="translated">由于可能的元组类型元素创建，已禁用自动选择。</target>
         <note />
       </trans-unit>
+      <trans-unit id="pattern_variable">
+        <source>&lt;pattern variable&gt;</source>
+        <target state="new">&lt;pattern variable&gt;</target>
+        <note />
+      </trans-unit>
       <trans-unit id="range_variable">
         <source>&lt;range variable&gt;</source>
         <target state="translated">&lt;范围变量&gt;</target>

src/Features/CSharp/Portable/xlf/CSharpFeaturesResources.zh-Hant.xlf

@@ -77,6 +77,11 @@
         <target state="new">Assign to '{0}'</target>
         <note />
       </trans-unit>
+      <trans-unit id="Autoselect_disabled_due_to_potential_pattern_variable_declaration">
+        <source>Autoselect disabled due to potential pattern variable declaration.</source>
+        <target state="new">Autoselect disabled due to potential pattern variable declaration.</target>
+        <note />
+      </trans-unit>
       <trans-unit id="Compare_to_0">
         <source>Compare to '{0}'</source>
         <target state="new">Compare to '{0}'</target>
@@ -237,6 +242,11 @@
         <target state="translated">因為可能建立元組類型元素，所以停用自動選擇。</target>
         <note />
       </trans-unit>
+      <trans-unit id="pattern_variable">
+        <source>&lt;pattern variable&gt;</source>
+        <target state="new">&lt;pattern variable&gt;</target>
+        <note />
+      </trans-unit>
       <trans-unit id="range_variable">
         <source>&lt;range variable&gt;</source>
         <target state="translated">&lt;範圍變數&gt;</target>