fix(tests): add cache reset and HTML→MD transitions for test isolation

Add __resetCacheForTest helper in bridge.js to clear iframe doc cache.
Add beforeAll HTML→MD transitions in each describe block to ensure
clean md state when running all livepreview suites together. Fixes
cross-contamination from prior suites that left stale cache entries.
All 227 livepreview tests pass consistently.

Author: abose

src-mdviewer/src/bridge.js

@@ -122,6 +122,9 @@ export function initBridge() {
     window.__getWorkingSetPaths = function () {
         return docCache._getWorkingSetPathsForTest();
     };
+    window.__resetCacheForTest = function () {
+        docCache.clearAll();
+    };
     window.__triggerContentSync = function () {
         const content = document.getElementById("viewer-content");
         if (content) {

test/spec/md-editor-edit-integ-test.js

@@ -128,11 +128,6 @@ define(function (require, exports, module) {
                 await awaitsFor(() =>
                     LiveDevMultiBrowser.status === LiveDevMultiBrowser.STATUS_ACTIVE,
                 "live dev to open", 20000);
-
-                // Open the checkbox test md file
-                await awaitsForDone(SpecRunnerUtils.openProjectFiles(["checkbox-test.md"]),
-                    "open checkbox-test.md");
-                await _waitForMdPreviewReady(EditorManager.getActiveEditor());
             }
         }, 30000);
 
@@ -155,6 +150,12 @@ define(function (require, exports, module) {
 
         describe("Checkbox (Task List) Sync", function () {
 
+            beforeAll(async function () {
+                // Ensure clean md state by switching HTML→MD
+                await awaitsForDone(SpecRunnerUtils.openProjectFiles(["simple.html"]),
+                    "open simple.html to reset md state");
+            }, 10000);
+
             async function _openMdFile(fileName) {
                 await awaitsForDone(SpecRunnerUtils.openProjectFiles([fileName]),
                     "open " + fileName);
@@ -239,6 +240,11 @@ define(function (require, exports, module) {
 
         describe("Code Block Editing", function () {
 
+            beforeAll(async function () {
+                await awaitsForDone(SpecRunnerUtils.openProjectFiles(["simple.html"]),
+                    "open simple.html to reset md state");
+            }, 10000);
+
             async function _openMdFile(fileName) {
                 await awaitsForDone(SpecRunnerUtils.openProjectFiles([fileName]),
                     "open " + fileName);
@@ -616,6 +622,11 @@ define(function (require, exports, module) {
 
         describe("List Editing", function () {
 
+            beforeAll(async function () {
+                await awaitsForDone(SpecRunnerUtils.openProjectFiles(["simple.html"]),
+                    "open simple.html to reset md state");
+            }, 10000);
+
             async function _openMdFile(fileName) {
                 await awaitsForDone(SpecRunnerUtils.openProjectFiles([fileName]),
                     "open " + fileName);
@@ -988,7 +999,9 @@ define(function (require, exports, module) {
                 "End of list test.\n";
 
             beforeAll(async function () {
-                // Open file once — keep it open for all tests in this describe
+                // Reset md state then open file
+                await awaitsForDone(SpecRunnerUtils.openProjectFiles(["simple.html"]),
+                    "open simple.html to reset md state");
                 await awaitsForDone(SpecRunnerUtils.openProjectFiles(["list-test.md"]),
                     "open list-test.md");
                 await _waitForMdPreviewReady(EditorManager.getActiveEditor());
@@ -1234,6 +1247,8 @@ define(function (require, exports, module) {
                 "## Heading Two\n\nAnother paragraph.\n\n### Heading Three\n\nFinal paragraph.\n";
 
             beforeAll(async function () {
+                await awaitsForDone(SpecRunnerUtils.openProjectFiles(["simple.html"]),
+                    "open simple.html to reset md state");
                 await awaitsForDone(SpecRunnerUtils.openProjectFiles(["heading-test.md"]),
                     "open heading-test.md");
                 await _waitForMdPreviewReady(EditorManager.getActiveEditor());

test/spec/md-editor-edit-more-integ-test.js

@@ -170,8 +170,19 @@ define(function (require, exports, module) {
                 await awaitsForDone(SpecRunnerUtils.openProjectFiles(["doc1.md"]),
                     "open doc1.md");
                 await _waitForMdPreviewReady(EditorManager.getActiveEditor());
+                // Reset cache after iframe is ready (clears stale entries from prior suites)
+                const win = _getMdIFrameWin();
+                if (win && win.__resetCacheForTest) {
+                    win.__resetCacheForTest();
+                }
+                // Re-open to get a fresh render after cache reset
+                await awaitsForDone(SpecRunnerUtils.openProjectFiles(["simple.html"]),
+                    "open simple.html to reset");
+                await awaitsForDone(SpecRunnerUtils.openProjectFiles(["doc1.md"]),
+                    "reopen doc1.md");
+                await _waitForMdPreviewReady(EditorManager.getActiveEditor());
                 await _enterEditMode();
-            }, 15000);
+            }, 20000);
 
             afterAll(async function () {
                 await awaitsForDone(CommandManager.execute(Commands.FILE_CLOSE, { _forceClose: true }),

test/spec/md-editor-integ-test.js

@@ -266,6 +266,17 @@ define(function (require, exports, module) {
                 await awaitsForDone(SpecRunnerUtils.openProjectFiles(["test-shortcuts.md"]),
                     "open test-shortcuts.md");
                 await _waitForMdPreviewReady(EditorManager.getActiveEditor());
+                // Reset iframe doc cache for predictable test state
+                const win = _getMdIFrameWin();
+                if (win && win.__resetCacheForTest) {
+                    win.__resetCacheForTest();
+                }
+                // Re-open to get fresh render after cache reset
+                await awaitsForDone(SpecRunnerUtils.openProjectFiles(["simple1.html"]),
+                    "open simple1.html to reset");
+                await awaitsForDone(SpecRunnerUtils.openProjectFiles(["test-shortcuts.md"]),
+                    "reopen test-shortcuts.md");
+                await _waitForMdPreviewReady(EditorManager.getActiveEditor());
                 testFilePath = testFolder + "/test-shortcuts.md";
             }
         }, 30000);