import: add support to import any xml tab element to XmlComponent (#8)

- make method to import/convert to XmlComponent
 - expose method to add childElement to Header/Footer
 - add tests

src/file/xml-components/imported-xml-component.spec.ts

@@ -1,5 +1,52 @@
 import { expect } from "chai";
-import { ImportedXmlComponent } from "./";
+import { ImportedXmlComponent, convertToXmlComponent } from "./";
+
+const xmlString = `
+        <w:p w:one="value 1" w:two="value 2">
+            <w:rPr>
+                <w:noProof>some value</w:noProof>
+            </w:rPr>
+            <w:r active="true">
+                <w:t>Text 1</w:t>
+            </w:r>
+            <w:r active="true">
+                <w:t>Text 2</w:t>
+            </w:r>                
+        </w:p>
+    `;
+
+const importedXmlElement = {
+    "w:p": {
+        _attr: { "w:one": "value 1", "w:two": "value 2" },
+        "w:rPr": { "w:noProof": "some value" },
+        "w:r": [{ _attr: { active: "true" }, "w:t": "Text 1" }, { _attr: { active: "true" }, "w:t": "Text 2" }],
+    },
+};
+
+const convertedXmlElement = {
+    deleted: false,
+    rootKey: "w:p",
+    root: [
+        {
+            deleted: false,
+            rootKey: "w:rPr",
+            root: [{ deleted: false, rootKey: "w:noProof", root: ["some value"] }],
+        },
+        {
+            deleted: false,
+            rootKey: "w:r",
+            root: [{ deleted: false, rootKey: "w:t", root: ["Text 1"] }],
+            _attr: { active: "true" },
+        },
+        {
+            deleted: false,
+            rootKey: "w:r",
+            root: [{ deleted: false, rootKey: "w:t", root: ["Text 2"] }],
+            _attr: { active: "true" },
+        },
+    ],
+    _attr: { "w:one": "value 1", "w:two": "value 2" },
+};
 
 describe("ImportedXmlComponent", () => {
     let importedXmlComponent: ImportedXmlComponent;
@@ -31,4 +78,16 @@ describe("ImportedXmlComponent", () => {
             });
         });
     });
+
+    it("should create XmlComponent from xml string", () => {
+        const converted = ImportedXmlComponent.fromXmlString(xmlString);
+        expect(converted).to.eql(convertedXmlElement);
+    });
+
+    describe("convertToXmlComponent", () => {
+        it("should convert to xml component", () => {
+            const converted = convertToXmlComponent("w:p", importedXmlElement["w:p"]);
+            expect(converted).to.eql(convertedXmlElement);
+        });
+    });
 });