fix: #745 - Inserting a member when a comment was the last member wou…

…ld throw.

src/manipulation/helpers/getInsertPosFromIndex.ts

@@ -42,7 +42,7 @@ export function getEndPosFromIndex(index: number, parent: Node, children: Node[]
             if (closeBraceToken == null)
                 endPos = parent.getEnd();
             else
-                endPos = closeBraceToken.getNonWhitespaceStart();
+                endPos = closeBraceToken.getStart();
         }
     }
     else {

src/manipulation/manipulations/insertion.ts

@@ -252,13 +252,14 @@ export interface InsertIntoBracesOrSourceFileOptions {
 export function insertIntoBracesOrSourceFile(opts: InsertIntoBracesOrSourceFileOptions) {
     const { parent, index, children } = opts;
     const fullText = parent._sourceFile.getFullText();
-    const insertPos = getInsertPosFromIndex(index, parent.getChildSyntaxListOrThrow(), children);
+    const childSyntaxList = parent.getChildSyntaxListOrThrow();
+    const insertPos = getInsertPosFromIndex(index, childSyntaxList, children);
     const endPos = getEndPosFromIndex(index, parent, children, fullText);
     const replacingLength = endPos - insertPos;
     const newText = getNewText();
 
     doManipulation(parent._sourceFile, new InsertionTextManipulator({ insertPos, replacingLength, newText }), new NodeHandlerFactory().getForParentRange({
-        parent: parent.getChildSyntaxListOrThrow(),
+        parent: childSyntaxList,
         start: insertPos,
         end: insertPos + newText.length,
         replacingLength

src/tests/issues/745tests.ts

@@ -0,0 +1,30 @@
+import { expect } from "chai";
+import { Project } from "../../Project";
+
+describe("tests for issue #45", () => {
+    it("should not error when adding a constructor and the class only has an empty comment in the body", () => {
+        const project = new Project({ useVirtualFileSystem: true });
+        const sourceFile = project.createSourceFile("src/MyClass.ts", `class Foo {
+//
+}`);
+        const classDec = sourceFile.getClasses()[0];
+        classDec.addConstructor({
+            statements: "console.log('test');",
+        });
+
+        expect(sourceFile.getFullText()).to.equal("class Foo {\n//\n\n    constructor() {\n        console.log('test');\n    }\n}");
+    });
+
+    it("should not error when there is a comment on the close brace token", () => {
+        const project = new Project({ useVirtualFileSystem: true });
+        const sourceFile = project.createSourceFile("src/MyClass.ts", `class Foo {
+//
+/*b*/}`);
+        const classDec = sourceFile.getClasses()[0];
+        classDec.insertConstructor(1, {
+            statements: "console.log('test');",
+        });
+
+        expect(sourceFile.getFullText()).to.equal("class Foo {\n//\n\n    constructor() {\n        console.log('test');\n    }\n\n/*b*/}");
+    });
+});

src/tests/projectTests.ts

@@ -1199,6 +1199,7 @@ describe(nameof(Project), () => {
 
     describe(nameof<Project>(t => t.forgetNodesCreatedInBlock), () => {
         describe("synchronous", () => {
+            // todo: this should be moved into an "it" block
             const project = new Project({ useVirtualFileSystem: true });
             let sourceFile: SourceFile;
             let sourceFileNotNavigated: SourceFile;