tsickle: emit comment after missing semicolon only once

src/jsdoc_transformer.ts

@@ -846,10 +846,9 @@ export function jsdocTransformer(
               continue;
             }
           }
-          const newDecl =
-              // TODO: go/ts50upgrade - Remove after upgrade.
-              // tslint:disable-next-line:no-unnecessary-type-assertion
-              ts.visitNode(decl, visitor, ts.isVariableDeclaration)!;
+          const newDecl = ts.setEmitFlags(
+              ts.visitNode(decl, visitor, ts.isVariableDeclaration)!,
+              ts.EmitFlags.NoComments);
           const newStmt = ts.factory.createVariableStatement(
               varStmt.modifiers,
               ts.factory.createVariableDeclarationList([newDecl], flags));

src/summary.ts

@@ -54,6 +54,7 @@ export class FileSummary {
   modName: string|undefined;
   autochunk = false;
   enhanceable = false;
+  legacyNamespace = false;
   moduleType = ModuleType.UNKNOWN;
 
   private stringify(symbol: Symbol): string {

src/ts_migration_exports_shim.ts

@@ -457,6 +457,9 @@ class Generator {
     fileSummary.addStrongRequire({type: Type.CLOSURE, name: 'goog'});
     fileSummary.addStrongRequire(
         {type: Type.CLOSURE, name: this.srcIds.googModuleId});
+    if (maybeDeclareLegacyNameCall) {
+      fileSummary.legacyNamespace = true;
+    }
 
     fileSummary.autochunk = isAutoChunk;
     fileSummary.moduleType = ModuleType.GOOG_MODULE;

test_files/comments/trailing_no_semicolon.js

@@ -0,0 +1,22 @@
+/**
+ *
+ * @fileoverview Tests that the JSDoc comment of `other` is only emitted once.
+ * Without the trailing semicolon after `noExplicitSemicolon` TypeScript seems
+ * to duplicate the trailing comment as soon as a custom transformer modifies
+ * the variable statement.
+ *
+ * Generated from: test_files/comments/trailing_no_semicolon.ts
+ */
+goog.module('test_files.comments.trailing_no_semicolon');
+var module = module || { id: 'test_files/comments/trailing_no_semicolon.ts' };
+goog.require('tslib');
+/** @type {number} */
+const noExplicitSemicolon = 0;
+/**
+ * This is a comment with a JSDoc tag
+ * JSCompiler doesn't recognize
+ *
+ * \@foobar
+ * @type {number}
+ */
+exports.other = 1;

test_files/comments/trailing_no_semicolon.ts

@@ -0,0 +1,17 @@
+/**
+ * @fileoverview Tests that the JSDoc comment of `other` is only emitted once.
+ * Without the trailing semicolon after `noExplicitSemicolon` TypeScript seems
+ * to duplicate the trailing comment as soon as a custom transformer modifies
+ * the variable statement.
+ */
+
+
+const noExplicitSemicolon = 0
+
+/**
+ * This is a comment with a JSDoc tag
+ * JSCompiler doesn't recognize
+ *
+ * @foobar
+ */
+export const other = 1;