fix(47597): ignore commented imports following template expression

Author: a-tarasyuk

src/services/preProcess.ts

@@ -345,6 +345,23 @@ namespace ts {
                     break;
                 }
 
+                if (scanner.getToken() === SyntaxKind.TemplateHead) {
+                    while (true) {
+                        if (scanner.getToken() === SyntaxKind.EndOfFileToken) {
+                            break;
+                        }
+                        if (scanner.getToken() === SyntaxKind.ImportKeyword) {
+                            tryConsumeImport();
+                        }
+                        if (scanner.getToken() === SyntaxKind.CloseBraceToken) {
+                            scanner.reScanTemplateToken(/*isTaggedTemplate*/ false);
+                            break;
+                        }
+                        scanner.scan();
+                    }
+                    nextToken();
+                }
+
                 // check if at least one of alternative have moved scanner forward
                 if (tryConsumeDeclare() ||
                     tryConsumeImport() ||

src/testRunner/unittests/services/preProcessFile.ts

@@ -176,6 +176,74 @@ describe("unittests:: services:: PreProcessFile:", () => {
             });
         });
 
+        it("Correctly ignore commented imports following template expression", () => {
+            /* eslint-disable no-template-curly-in-string */
+            test("/**" + "\n" +
+                " * Before" + "\n" +
+                " * ```" + "\n" +
+                " * import * as a from \"a\";" + "\n" +
+                " * ```" + "\n" +
+                " */" + "\n" +
+                "type Foo = `${string}`;" + "\n" +
+                "/**" + "\n" +
+                " * After" + "\n" +
+                " * ```" + "\n" +
+                " * import { B } from \"b\";" + "\n" +
+                " * import * as c from \"c\";" + "\n" +
+                " * ```" + "\n" +
+                " */",
+            /*readImportFile*/ true,
+            /*detectJavaScriptImports*/ true,
+            {
+                referencedFiles: [],
+                typeReferenceDirectives: [],
+                libReferenceDirectives: [],
+                importedFiles: [],
+                ambientExternalModules: undefined,
+                isLibFile: false
+            });
+            /* eslint-enable no-template-curly-in-string */
+        });
+
+        it("Correctly returns imports after a template expression", () => {
+            /* eslint-disable no-template-curly-in-string */
+            test("`${foo}`; import \"./foo\";",
+            /*readImportFile*/ true,
+            /*detectJavaScriptImports*/ true,
+            {
+                referencedFiles: [],
+                typeReferenceDirectives: [],
+                libReferenceDirectives: [],
+                importedFiles: [
+                    { fileName: "./foo", pos: 17, end: 22 }
+                ],
+                ambientExternalModules: undefined,
+                isLibFile: false
+            });
+            /* eslint-enable no-template-curly-in-string */
+        });
+
+        it("Correctly returns dynamic imports from template expression", () => {
+            /* eslint-disable no-template-curly-in-string */
+            test("`${(<div>Text `` ${} text {} " + "\n" +
+                "${import(\"a\")} {import(\"b\")} " + "\n" +
+                "${/* A comment */} ${/* import(\"ignored\") */} </div>)}`",
+            /*readImportFile*/ true,
+            /*detectJavaScriptImports*/ true,
+            {
+                referencedFiles: [],
+                typeReferenceDirectives: [],
+                libReferenceDirectives: [],
+                importedFiles: [
+                    { fileName: "a", pos: 39, end: 40 },
+                    { fileName: "b", pos: 53, end: 54 }
+                ],
+                ambientExternalModules: undefined,
+                isLibFile: false
+            });
+            /* eslint-enable no-template-curly-in-string */
+        });
+
         it("Correctly return ES6 exports", () => {
             test("export * from \"m1\";" + "\n" +
                 "export {a} from \"m2\";" + "\n" +