diff --git a/src/interfaces/nodes/IFunctionNode.d.ts b/src/interfaces/nodes/IFunctionNode.d.ts
index 50ed7d98..9665db0b 100644
--- a/src/interfaces/nodes/IFunctionNode.d.ts
+++ b/src/interfaces/nodes/IFunctionNode.d.ts
@@ -1,10 +1,11 @@
+import { IBlockStatementNode } from "./IBlockStatementNode";
 import { IIdentifierNode } from "./IIdentifierNode";
 import { INode } from "./INode";
 
 export interface IFunctionNode extends INode {
     id: IIdentifierNode;
     params: IIdentifierNode[];
-    body: INode[];
+    body: IBlockStatementNode;
     generator: boolean;
     expression: boolean;
 }
diff --git a/src/types/TBlockScopeNode.d.ts b/src/types/TBlockScopeNode.d.ts
index 6723bc78..28968cc7 100644
--- a/src/types/TBlockScopeNode.d.ts
+++ b/src/types/TBlockScopeNode.d.ts
@@ -1,6 +1,5 @@
 import { IBlockStatementNode } from "../interfaces/nodes/IBlockStatementNode";
 import { ICatchClauseNode } from "../interfaces/nodes/ICatchClauseNode";
-import { IFunctionNode } from "../interfaces/nodes/IFunctionNode";
 import { IProgramNode } from "../interfaces/nodes/IProgramNode";
 
-export type TBlockScopeNode = IBlockStatementNode|ICatchClauseNode|IFunctionNode|IProgramNode;
\ No newline at end of file
+export type TBlockScopeNode = IBlockStatementNode|ICatchClauseNode|IProgramNode;
\ No newline at end of file
diff --git a/test/NodeUtils.spec.ts b/test/NodeUtils.spec.ts
index 51a837f3..73611ed5 100644
--- a/test/NodeUtils.spec.ts
+++ b/test/NodeUtils.spec.ts
@@ -1,10 +1,12 @@
 import { IBlockStatementNode } from "../src/interfaces/nodes/IBlockStatementNode";
 import { IIdentifierNode } from "../src/interfaces/nodes/IIdentifierNode";
 import { ILiteralNode } from "../src/interfaces/nodes/ILiteralNode";
+import { IProgramNode } from "../src/interfaces/nodes/IProgramNode";
 
 import { NodeType } from "../src/enums/NodeType";
 
 import { NodeUtils } from '../src/NodeUtils';
+import {IFunctionDeclarationNode} from "../src/interfaces/nodes/IFunctionDeclarationNode";
 
 let assert: any = require('chai').assert;
 
@@ -70,14 +72,14 @@ describe('NodeUtils', () => {
             };
 
             literalNode = {
-                type: NodeType.Identifier,
+                type: NodeType.Literal,
                 value: 'string',
                 raw: `'string'`,
                 'x-verbatim-property': `'string'`
             };
 
             blockStatementNode = {
-                type: NodeType.Literal,
+                type: NodeType.BlockStatement,
                 body: [
                     identifierNode,
                     literalNode
@@ -98,4 +100,178 @@ describe('NodeUtils', () => {
             assert.deepEqual(NodeUtils.getBlockScopeNodeByIndex(identifierNode, 1), identifierNode);
         });
     });
+
+    describe('getBlockScopeOfNode (node: INode, depth: number = 0): TBlockScopeNode', () => {
+        let blockStatementNode: IBlockStatementNode,
+            identifierNode: IIdentifierNode,
+            functionDeclarationNode: IFunctionDeclarationNode,
+            literalNode: ILiteralNode,
+            programNode: IProgramNode;
+
+        beforeEach(() => {
+            identifierNode = {
+                type: NodeType.Identifier,
+                name: 'identifier',
+            };
+
+            literalNode = {
+                type: NodeType.Literal,
+                value: 'string',
+                raw: `'string'`,
+                'x-verbatim-property': `'string'`
+            };
+
+            blockStatementNode = {
+                type: NodeType.BlockStatement,
+                body: [
+                    identifierNode,
+                    literalNode
+                ]
+            };
+
+            functionDeclarationNode = {
+                type: NodeType.FunctionDeclaration,
+                id: {
+                    type: NodeType.Identifier,
+                    name: 'test'
+                },
+                params: [],
+                body: blockStatementNode,
+                generator: false,
+                expression: false
+            };
+
+            programNode = {
+                type: NodeType.Program,
+                body: [functionDeclarationNode]
+            };
+
+            programNode['parentNode'] = programNode;
+            functionDeclarationNode['parentNode'] = programNode;
+            blockStatementNode['parentNode'] = functionDeclarationNode;
+            identifierNode['parentNode'] = blockStatementNode;
+            literalNode['parentNode'] = blockStatementNode;
+        });
+
+        it('should return block-scope node for given node', () => {
+            assert.deepEqual(NodeUtils.getBlockScopeOfNode(identifierNode), blockStatementNode);
+            assert.deepEqual(NodeUtils.getBlockScopeOfNode(identifierNode, 1), programNode);
+            assert.deepEqual(NodeUtils.getBlockScopeOfNode(functionDeclarationNode), programNode);
+            assert.deepEqual(NodeUtils.getBlockScopeOfNode(programNode), programNode);
+        });
+    });
+
+    describe('insertNodeAtIndex (blockScopeBody: INode[], node: INode, index: number): void', () => {
+        let blockStatementNode: IBlockStatementNode,
+            expectedBlockStatementNode: IBlockStatementNode,
+            identifierNode: IIdentifierNode,
+            literalNode: ILiteralNode;
+
+        beforeEach(() => {
+            identifierNode = {
+                type: NodeType.Identifier,
+                name: 'identifier'
+            };
+
+            literalNode = {
+                type: NodeType.Literal,
+                value: 'string',
+                raw: `'string'`,
+                'x-verbatim-property': `'string'`
+            };
+
+            blockStatementNode = {
+                type: NodeType.BlockStatement,
+                body: [
+                    identifierNode
+                ]
+            };
+
+            expectedBlockStatementNode = Object.assign({}, blockStatementNode);
+            expectedBlockStatementNode['body'].push(literalNode);
+
+            NodeUtils.insertNodeAtIndex(blockStatementNode.body, literalNode, 1);
+        });
+
+        it('should insert given node in block-scope body at index', () => {
+            assert.deepEqual(blockStatementNode, expectedBlockStatementNode);
+        });
+    });
+
+    describe('parentize (node: INode): void', () => {
+        let blockStatementNode: IBlockStatementNode,
+            identifierNode: IIdentifierNode,
+            literalNode: ILiteralNode,
+            programNode: IProgramNode;
+
+        beforeEach(() => {
+            identifierNode = {
+                type: NodeType.Identifier,
+                name: 'identifier'
+            };
+
+            literalNode = {
+                type: NodeType.Literal,
+                value: 'string',
+                raw: `'string'`,
+                'x-verbatim-property': `'string'`
+            };
+
+            blockStatementNode = {
+                type: NodeType.BlockStatement,
+                body: [
+                    identifierNode,
+                    literalNode
+                ]
+            };
+
+            programNode = {
+                type: NodeType.Program,
+                body: [blockStatementNode]
+            };
+
+            NodeUtils.parentize(blockStatementNode);
+        });
+
+        it('should parentize given AST-tree', () => {
+            assert.deepEqual(blockStatementNode['parentNode'], programNode);
+            assert.deepEqual(identifierNode['parentNode'], blockStatementNode);
+            assert.deepEqual(literalNode['parentNode'], blockStatementNode);
+        });
+    });
+
+    describe('prependNode (blockScopeBody: INode[], node: INode): void', () => {
+        let blockStatementNode: IBlockStatementNode,
+            expectedBlockStatementNode: IBlockStatementNode,
+            identifierNode: IIdentifierNode,
+            literalNode: ILiteralNode;
+
+        beforeEach(() => {
+            identifierNode = {
+                type: NodeType.Identifier,
+                name: 'identifier'
+            };
+
+            literalNode = {
+                type: NodeType.Literal,
+                value: 'string',
+                raw: `'string'`,
+                'x-verbatim-property': `'string'`
+            };
+
+            blockStatementNode = {
+                type: NodeType.Literal,
+                body: [identifierNode]
+            };
+
+            expectedBlockStatementNode = Object.assign({}, blockStatementNode);
+            expectedBlockStatementNode['body'].unshift(literalNode);
+
+            NodeUtils.prependNode(blockStatementNode.body, literalNode)
+        });
+
+        it('should prepend given node to a `BlockStatement` node body', () => {
+            assert.deepEqual(blockStatementNode, expectedBlockStatementNode);
+        });
+    });
 });
\ No newline at end of file