add getter for static initializer blocks

Author: erik-krogh

javascript/ql/lib/semmle/javascript/Classes.qll

@@ -258,6 +258,11 @@ class ClassDefinition extends @class_definition, ClassOrInterface, AST::ValueNod
   }
 
   override string getAPrimaryQlClass() { result = "ClassDefinition" }
+
+  /**
+   * Gets a static initializer of this class, if any.
+   */
+  BlockStmt getAStaticInitializerBlock() { result.getParent() = this }
 }
 
 /**

javascript/ql/test/library-tests/TypeScript/Types/tests.expected

@@ -670,3 +670,6 @@ unionIndex
 | { stillMyUnion: true; } | 1 | MyUnion \| { yetAnotherType: true; } |
 | { stillMyUnion: true; } | 1 | { myUnion: true; } \| { stillMyUnion: true; } |
 | { yetAnotherType: true; } | 2 | MyUnion \| { yetAnotherType: true; } |
+getAStaticInitializerBlock
+| tst.ts:179:3:192:3 | class F ...    \\n  } | tst.ts:185:5:187:5 | static  ... ;\\n    } |
+| tst.ts:179:3:192:3 | class F ...    \\n  } | tst.ts:188:5:190:5 | static  ... ;\\n    } |

javascript/ql/test/library-tests/TypeScript/Types/tests.ql

@@ -39,3 +39,7 @@ query predicate unknownType(Expr e, Type type) {
 query CallSignatureType abstractSignature() { result.isAbstract() }
 
 query UnionType unionIndex(Type element, int i) { result.getElementType(i) = element }
+
+query BlockStmt getAStaticInitializerBlock(ClassDefinition cls) {
+  result = cls.getAStaticInitializerBlock()
+}