add tests to add and remove members in class

src/harness/unittests/textChanges.ts

@@ -667,5 +667,47 @@ class A {
                 }
             });
         }
+        {
+            const text = `
+class A {
+    x
+}
+`;
+            runSingleFileTest("insertNodeAfterInClass1", noop, text, /*validateNodes*/ false, (sourceFile, changeTracker) => {
+                changeTracker.insertNodeAfter(sourceFile, findChild("x", sourceFile), createProperty(undefined, undefined, "a", undefined, createKeywordTypeNode(SyntaxKind.BooleanKeyword), undefined), { suffix: newLineCharacter });
+            });
+        }
+        {
+            const text = `
+class A {
+    x;
+}
+`;
+            runSingleFileTest("insertNodeAfterInClass2", noop, text, /*validateNodes*/ false, (sourceFile, changeTracker) => {
+                changeTracker.insertNodeAfter(sourceFile, findChild("x", sourceFile), createProperty(undefined, undefined, "a", undefined, createKeywordTypeNode(SyntaxKind.BooleanKeyword), undefined), { suffix: newLineCharacter });
+            });
+        }
+        {
+            const text = `
+class A {
+    x;
+    y = 1;
+}
+`;
+            runSingleFileTest("deleteNodeAfterInClass1", noop, text, /*validateNodes*/ false, (sourceFile, changeTracker) => {
+                changeTracker.deleteNode(sourceFile, findChild("x", sourceFile));
+            });
+        }
+        {
+            const text = `
+class A {
+    x
+    y = 1;
+}
+`;
+            runSingleFileTest("deleteNodeAfterInClass2", noop, text, /*validateNodes*/ false, (sourceFile, changeTracker) => {
+                changeTracker.deleteNode(sourceFile, findChild("x", sourceFile));
+            });
+        }
     });
 }

tests/baselines/reference/textChanges/deleteNodeAfterInClass1.js

@@ -0,0 +1,12 @@
+===ORIGINAL===
+
+class A {
+    x;
+    y = 1;
+}
+
+===MODIFIED===
+
+class A {
+    y = 1;
+}

tests/baselines/reference/textChanges/deleteNodeAfterInClass2.js

@@ -0,0 +1,12 @@
+===ORIGINAL===
+
+class A {
+    x
+    y = 1;
+}
+
+===MODIFIED===
+
+class A {
+    y = 1;
+}

tests/baselines/reference/textChanges/insertNodeAfterInClass1.js

@@ -0,0 +1,12 @@
+===ORIGINAL===
+
+class A {
+    x
+}
+
+===MODIFIED===
+
+class A {
+    x
+    a: boolean;
+}

tests/baselines/reference/textChanges/insertNodeAfterInClass2.js

@@ -0,0 +1,12 @@
+===ORIGINAL===
+
+class A {
+    x;
+}
+
+===MODIFIED===
+
+class A {
+    x;
+    a: boolean;
+}