functions and specs: removeExistingElements

packages/mermaid/src/mermaidAPI.spec.ts

@@ -4,7 +4,7 @@ import { vi } from 'vitest';
 import mermaid from './mermaid';
 import { MermaidConfig } from './config.type';
 
-import mermaidAPI from './mermaidAPI';
+import mermaidAPI, { removeExistingElements } from './mermaidAPI';
 import {
   encodeEntities,
   decodeEntities,
@@ -454,6 +454,76 @@ describe('when using mermaidAPI and ', function () {
     });
   });
 
+  describe('removeExistingElements', () => {
+    const svgId = 'svgId';
+    const tempDivId = 'tempDivId';
+    const tempIframeId = 'tempIFrameId';
+    const givenDocument = new Document();
+    const rootHtml = givenDocument.createElement('html');
+    givenDocument.append(rootHtml);
+
+    const svgElement = givenDocument.createElement('svg'); // doesn't matter what the tag is in the test
+    svgElement.id = svgId;
+    const tempDivElement = givenDocument.createElement('div'); // doesn't matter what the tag is in the test
+    tempDivElement.id = tempDivId;
+    const tempiFrameElement = givenDocument.createElement('div'); // doesn't matter what the tag is in the test
+    tempiFrameElement.id = tempIframeId;
+
+    it('removes an existing element with given id', () => {
+      rootHtml.appendChild(svgElement);
+      expect(givenDocument.getElementById(svgElement.id)).toEqual(svgElement);
+      removeExistingElements(givenDocument, false, svgId, tempDivId, tempIframeId);
+      expect(givenDocument.getElementById(svgElement.id)).toBeNull();
+    });
+
+    describe('is in sandboxed mode', () => {
+      const inSandboxedMode = true;
+
+      it('removes an existing element with the given iFrame selector', () => {
+        tempiFrameElement.append(svgElement);
+        rootHtml.append(tempiFrameElement);
+        rootHtml.append(tempDivElement);
+
+        expect(givenDocument.getElementById(tempIframeId)).toEqual(tempiFrameElement);
+        expect(givenDocument.getElementById(tempDivId)).toEqual(tempDivElement);
+        expect(givenDocument.getElementById(svgId)).toEqual(svgElement);
+        removeExistingElements(
+          givenDocument,
+          inSandboxedMode,
+          svgId,
+          '#' + tempDivId,
+          '#' + tempIframeId
+        );
+        expect(givenDocument.getElementById(tempDivId)).toEqual(tempDivElement);
+        expect(givenDocument.getElementById(tempIframeId)).toBeNull();
+        expect(givenDocument.getElementById(svgId)).toBeNull();
+      });
+    });
+    describe('not in sandboxed mode', () => {
+      const inSandboxedMode = false;
+
+      it('removes an existing element with the given enclosing div selector', () => {
+        tempDivElement.append(svgElement);
+        rootHtml.append(tempDivElement);
+        rootHtml.append(tempiFrameElement);
+
+        expect(givenDocument.getElementById(tempIframeId)).toEqual(tempiFrameElement);
+        expect(givenDocument.getElementById(tempDivId)).toEqual(tempDivElement);
+        expect(givenDocument.getElementById(svgId)).toEqual(svgElement);
+        removeExistingElements(
+          givenDocument,
+          inSandboxedMode,
+          svgId,
+          '#' + tempDivId,
+          '#' + tempIframeId
+        );
+        expect(givenDocument.getElementById(tempIframeId)).toEqual(tempiFrameElement);
+        expect(givenDocument.getElementById(tempDivId)).toBeNull();
+        expect(givenDocument.getElementById(svgId)).toBeNull();
+      });
+    });
+  });
+
   describe('doing initialize ', function () {
     beforeEach(function () {
       document.body.innerHTML = '';

packages/mermaid/src/mermaidAPI.ts

@@ -86,10 +86,10 @@ function parse(text: string, parseError?: ParseErrorFunction): boolean {
 export const encodeEntities = function (text: string): string {
   let txt = text;
 
-  txt = txt.replace(/style.*:\S*#.*;/g, function (s) {
+  txt = txt.replace(/style.*:\S*#.*;/g, function (s): string {
     return s.substring(0, s.length - 1);
   });
-  txt = txt.replace(/classDef.*:\S*#.*;/g, function (s) {
+  txt = txt.replace(/classDef.*:\S*#.*;/g, function (s): string {
     return s.substring(0, s.length - 1);
   });
 
@@ -319,6 +319,31 @@ function sandboxedIframe(parentNode: D3Element, iFrameId: string): D3Element {
     .attr('sandbox', '');
 }
 
+/**
+ * Remove any existing elements from the given document
+ *
+ * @param {Document} doc - the document to removed elements from
+ * @param {string} isSandboxed - whether or not we are in sandboxed mode
+ * @param {string} id - id for any existing SVG element
+ * @param {string} divSelector - selector for any existing enclosing div element
+ * @param {string} iFrameSelector - selector for any existing iFrame element
+ */
+export const removeExistingElements = (
+  doc: Document,
+  isSandboxed: boolean,
+  id: string,
+  divSelector: string,
+  iFrameSelector: string
+) => {
+  // Remove existing SVG element if it exists
+  const existingSvg = doc.getElementById(id);
+  if (existingSvg) existingSvg.remove();
+
+  // Remove previous temporary element if it exists
+  const element = isSandboxed ? doc.querySelector(iFrameSelector) : doc.querySelector(divSelector);
+  if (element) element.remove();
+};
+
 /**
  * Function that renders an svg with a graph from a chart definition. Usage example below.
  *
@@ -384,8 +409,8 @@ const render = async function (
 
   // -------------------------------------------------------------------------------
   // Define the root d3 node
-
   // In regular execution the svgContainingElement will be the element with a mermaid class
+
   if (typeof svgContainingElement !== 'undefined') {
     if (svgContainingElement) svgContainingElement.innerHTML = '';
 
@@ -400,19 +425,9 @@ const render = async function (
     appendDivSvgG(root, id, enclosingDivID, `font-family: ${fontFamily}`, XMLNS_XLINK_STD);
   } else {
     // No svgContainingElement was provided
-    // If there is an existing element with the id, we remove it
-    // this likely a previously rendered diagram
-    const existingSvg = document.getElementById(id);
-    if (existingSvg) existingSvg.remove();
 
-    // Remove previous temporary element if it exists
-    let element;
-    if (isSandboxed) {
-      element = document.querySelector(iFrameID_selector);
-    } else {
-      element = document.querySelector(enclosingDivID_selector);
-    }
-    if (element) element.remove();
+    // If there is an existing element with the id, we remove it. This likely a previously rendered diagram
+    removeExistingElements(document, isSandboxed, id, iFrameID_selector, enclosingDivID_selector);
 
     // Add the temporary div used for rendering with the enclosingDivID.
     // This temporary div will contain a svg with the id == id
@@ -420,7 +435,6 @@ const render = async function (
     if (isSandboxed) {
       // If we are in sandboxed mode, we do everything mermaid related in a (sandboxed) iFrame
       const iframe = sandboxedIframe(select('body'), iFrameID);
-
       root = select(iframe.nodes()[0]!.contentDocument!.body);
       root.node().style.margin = 0;
     } else root = select('body');