X-Git-Url: https://git.arvados.org/arvados-workbench2.git/blobdiff_plain/08ac60f877d6495a748747a3a0d30ca9f0e289d5..082c1782d96a4b1c897df64d9b325d102a5c1144:/cypress/support/commands.js

diff --git a/cypress/support/commands.js b/cypress/support/commands.js
index a28308e3..c2d78b54 100644
--- a/cypress/support/commands.js
+++ b/cypress/support/commands.js
@@ -401,3 +401,73 @@ function b64toBlob(b64Data, contentType = '', sliceSize = 512) {
     const blob = new Blob(byteArrays, { type: contentType });
     return blob
 }
+
+// From https://github.com/cypress-io/cypress/issues/7306#issuecomment-1076451070=
+// This command requires the async package (https://www.npmjs.com/package/async)
+Cypress.Commands.add('waitForDom', () => {
+    cy.window().then(win => {
+      let timeElapsed = 0;
+
+      cy.log("Waiting for DOM mutations to complete");
+
+      return new Cypress.Promise((resolve) => {
+        // set the required variables
+        let async = require("async");
+        let observerConfig = { attributes: true, childList: true, subtree: true };
+        let items = Array.apply(null, { length: 50 }).map(Number.call, Number);
+        win.mutationCount = 0;
+        win.previousMutationCount = null;
+
+        // create an observer instance
+        let observer = new win.MutationObserver((mutations) => {
+          mutations.forEach((mutation) => {
+            // Only record "attributes" type mutations that are not a "class" mutation.
+            // If the mutation is not an "attributes" type, then we always record it.
+            if (mutation.type === 'attributes' && mutation.attributeName !== 'class') {
+              win.mutationCount += 1;
+            } else if (mutation.type !== 'attributes') {
+              win.mutationCount += 1;
+            }
+          });
+
+          // initialize the previousMutationCount
+          if (win.previousMutationCount == null) win.previousMutationCount = 0;
+        });
+
+        // watch the document body for the specified mutations
+        observer.observe(win.document.body, observerConfig);
+
+        // check the DOM for mutations up to 50 times for a maximum time of 5 seconds
+        async.eachSeries(items, function iteratee(item, callback) {
+          // keep track of the elapsed time so we can log it at the end of the command
+          timeElapsed = timeElapsed + 100;
+
+          // make each iteration of the loop 100ms apart
+          setTimeout(() => {
+            if (win.mutationCount === win.previousMutationCount) {
+              // pass an argument to the async callback to exit the loop
+              return callback('Resolved - DOM changes complete.');
+            } else if (win.previousMutationCount != null) {
+              // only set the previous count if the observer has checked the DOM at least once
+              win.previousMutationCount = win.mutationCount;
+              return callback();
+            } else if (win.mutationCount === 0 && win.previousMutationCount == null && item === 4) {
+              // this is an early exit in case nothing is changing in the DOM. That way we only
+              // wait 500ms instead of the full 5 seconds when no DOM changes are occurring.
+              return callback('Resolved - Exiting early since no DOM changes were detected.');
+            } else {
+              // proceed to the next iteration
+              return callback();
+            }
+          }, 100);
+        }, function done() {
+          // Log the total wait time so users can see it
+          cy.log(`DOM mutations ${timeElapsed >= 5000 ? "did not complete" : "completed"} in ${timeElapsed} ms`);
+
+          // disconnect the observer and resolve the promise
+          observer.disconnect();
+          resolve();
+        });
+      });
+    });
+  });