C#: Implement using declaration statements.

calumgrant · calumgrant · commit 15cd1d274af6 · 2019-06-04T18:10:49.000+01:00
diff --git a/csharp/extractor/Semmle.Extraction.CSharp/Entities/Statements/LocalDeclaration.cs b/csharp/extractor/Semmle.Extraction.CSharp/Entities/Statements/LocalDeclaration.cs
@@ -1,3 +1,4 @@
+using Microsoft.CodeAnalysis;
 using Microsoft.CodeAnalysis.CSharp.Syntax;
 using Semmle.Extraction.CSharp.Entities.Expressions;
 using Semmle.Extraction.Kinds;
@@ -6,8 +7,17 @@ namespace Semmle.Extraction.CSharp.Entities.Statements
 {
     class LocalDeclaration : Statement<LocalDeclarationStatementSyntax>
     {
+        static StmtKind GetKind(LocalDeclarationStatementSyntax declStmt)
+        {
+            if (declStmt.UsingKeyword.RawKind != 0) return StmtKind.USING_DECL;
+
+            if (declStmt.IsConst) return StmtKind.CONST_DECL;
+
+            return StmtKind.VAR_DECL;
+        }
+
         LocalDeclaration(Context cx, LocalDeclarationStatementSyntax declStmt, IStatementParentEntity parent, int child)
-            : base(cx, declStmt, declStmt.IsConst ? StmtKind.CONST_DECL : StmtKind.VAR_DECL, parent, child) { }
+            : base(cx, declStmt, GetKind(declStmt), parent, child) { }
 
         public static LocalDeclaration Create(Context cx, LocalDeclarationStatementSyntax node, IStatementParentEntity parent, int child)
         {
diff --git a/csharp/extractor/Semmle.Extraction.CSharp/Kinds/StmtKind.cs b/csharp/extractor/Semmle.Extraction.CSharp/Kinds/StmtKind.cs
@@ -34,6 +34,7 @@ public enum StmtKind
         LABEL = 27,
         CATCH = 28,
         CASE = 29,
-        LOCAL_FUNCTION = 30
+        LOCAL_FUNCTION = 30,
+        USING_DECL = 31
     }
 }
diff --git a/csharp/ql/src/semmle/code/csharp/Stmt.qll b/csharp/ql/src/semmle/code/csharp/Stmt.qll
@@ -1254,6 +1254,17 @@ class LocalConstantDeclStmt extends LocalVariableDeclStmt, @const_decl_stmt {
   override string toString() { result = "const ... ...;" }
 }
 
+/**
+ * A `using` declaration statement, for example
+ *
+ * ```
+ * using FileStream f = File.Open("settings.xml");
+ * ```
+ */
+class UsingDeclStmt extends LocalVariableDeclStmt, @using_decl_stmt {
+  override string toString() { result = "using ... ...;" }
+}
+
 /**
  * An empty statement, for example line 2 in
  *
diff --git a/csharp/ql/src/semmlecode.csharp.dbscheme b/csharp/ql/src/semmlecode.csharp.dbscheme
@@ -808,11 +808,12 @@ case @stmt.kind of
 | 28 = @catch
 | 29 = @case_stmt
 | 30 = @local_function_stmt
+| 31 = @using_decl_stmt
   ;
 
 @labeled_stmt = @label_stmt | @case;
 
-@decl_stmt = @var_decl_stmt | @const_decl_stmt;
+@decl_stmt = @var_decl_stmt | @const_decl_stmt | @using_decl_stmt;
 
 @cond_stmt = @if_stmt | @switch_stmt;
 

Original file line number	Diff line number	Diff line change
`@@ -34,6 +34,7 @@ public enum StmtKind`
`34`	`34`	`LABEL = 27,`
`35`	`35`	`CATCH = 28,`
`36`	`36`	`CASE = 29,`
`37`		`- LOCAL_FUNCTION = 30`
	`37`	`+ LOCAL_FUNCTION = 30,`
	`38`	`+ USING_DECL = 31`
`38`	`39`	`}`
`39`	`40`	`}`