reuseProgramStructure.ts

/// <reference path="..\harness.ts" />
/// <reference path="..\..\harness\harnessLanguageService.ts" />

namespace ts {

    const enum ChangedPart {
        references = 1 << 0,
        importsAndExports = 1 << 1,
        program = 1 << 2
    }

    const newLine = "\r\n";

    interface SourceFileWithText extends SourceFile {
        sourceText?: SourceText;
    }

    export interface NamedSourceText {
        name: string;
        text: SourceText;
    }

    export interface ProgramWithSourceTexts extends Program {
        sourceTexts?: ReadonlyArray<NamedSourceText>;
        host: TestCompilerHost;
    }

    interface TestCompilerHost extends CompilerHost {
        getTrace(): string[];
    }

    export class SourceText implements IScriptSnapshot {
        private fullText: string;

        constructor(private references: string,
            private importsAndExports: string,
            private program: string,
            private changedPart: ChangedPart = 0,
            private version = 0) {
        }

        static New(references: string, importsAndExports: string, program: string): SourceText {
            Debug.assert(references !== undefined);
            Debug.assert(importsAndExports !== undefined);
            Debug.assert(program !== undefined);
            return new SourceText(references + newLine, importsAndExports + newLine, program || "");
        }

        public getVersion(): number {
            return this.version;
        }

        public updateReferences(newReferences: string): SourceText {
            Debug.assert(newReferences !== undefined);
            return new SourceText(newReferences + newLine, this.importsAndExports, this.program, this.changedPart | ChangedPart.references, this.version + 1);
        }
        public updateImportsAndExports(newImportsAndExports: string): SourceText {
            Debug.assert(newImportsAndExports !== undefined);
            return new SourceText(this.references, newImportsAndExports + newLine, this.program, this.changedPart | ChangedPart.importsAndExports, this.version + 1);
        }
        public updateProgram(newProgram: string): SourceText {
            Debug.assert(newProgram !== undefined);
            return new SourceText(this.references, this.importsAndExports, newProgram, this.changedPart | ChangedPart.program, this.version + 1);
        }

        public getFullText() {
            return this.fullText || (this.fullText = this.references + this.importsAndExports + this.program);
        }

        public getText(start: number, end: number): string {
            return this.getFullText().substring(start, end);
        }

        getLength(): number {
            return this.getFullText().length;
        }

        getChangeRange(oldSnapshot: IScriptSnapshot): TextChangeRange {
            const oldText = <SourceText>oldSnapshot;
            let oldSpan: TextSpan;
            let newLength: number;
            switch (oldText.changedPart ^ this.changedPart) {
                case ChangedPart.references:
                    oldSpan = createTextSpan(0, oldText.references.length);
                    newLength = this.references.length;
                    break;
                case ChangedPart.importsAndExports:
                    oldSpan = createTextSpan(oldText.references.length, oldText.importsAndExports.length);
                    newLength = this.importsAndExports.length;
                    break;
                case ChangedPart.program:
                    oldSpan = createTextSpan(oldText.references.length + oldText.importsAndExports.length, oldText.program.length);
                    newLength = this.program.length;
                    break;
                default:
                    Debug.assert(false, "Unexpected change");
            }

            return createTextChangeRange(oldSpan, newLength);
        }
    }

    function createSourceFileWithText(fileName: string, sourceText: SourceText, target: ScriptTarget) {
        const file = <SourceFileWithText>createSourceFile(fileName, sourceText.getFullText(), target);
        file.sourceText = sourceText;
        file.version = "" + sourceText.getVersion();
        return file;
    }

    export function createTestCompilerHost(texts: ReadonlyArray<NamedSourceText>, target: ScriptTarget, oldProgram?: ProgramWithSourceTexts): TestCompilerHost {
        const files = arrayToMap(texts, t => t.name, t => {
            if (oldProgram) {
                let oldFile = <SourceFileWithText>oldProgram.getSourceFile(t.name);
                if (oldFile && oldFile.redirectInfo) {
                    oldFile = oldFile.redirectInfo.unredirected;
                }
                if (oldFile && oldFile.sourceText.getVersion() === t.text.getVersion()) {
                    return oldFile;
                }
            }
            return createSourceFileWithText(t.name, t.text, target);
        });
        const trace: string[] = [];

        return {
            trace: s => trace.push(s),
            getTrace: () => trace,
            getSourceFile(fileName): SourceFile {
                return files.get(fileName);
            },
            getDefaultLibFileName(): string {
                return "lib.d.ts";
            },
            writeFile: notImplemented,
            getCurrentDirectory(): string {
                return "";
            },
            getDirectories(): string[] {
                return [];
            },
            getCanonicalFileName(fileName): string {
                return sys && sys.useCaseSensitiveFileNames ? fileName : fileName.toLowerCase();
            },
            useCaseSensitiveFileNames(): boolean {
                return sys && sys.useCaseSensitiveFileNames;
            },
            getNewLine(): string {
                return sys ? sys.newLine : newLine;
            },
            fileExists: fileName => files.has(fileName),
            readFile: fileName => {
                const file = files.get(fileName);
                return file && file.text;
            },
        };
    }

    export function newProgram(texts: NamedSourceText[], rootNames: string[], options: CompilerOptions): ProgramWithSourceTexts {
        const host = createTestCompilerHost(texts, options.target);
        const program = <ProgramWithSourceTexts>createProgram(rootNames, options, host);
        program.sourceTexts = texts;
        program.host = host;
        return program;
    }

    export function updateProgram(oldProgram: ProgramWithSourceTexts, rootNames: ReadonlyArray<string>, options: CompilerOptions, updater: (files: NamedSourceText[]) => void, newTexts?: NamedSourceText[]) {
        if (!newTexts) {
            newTexts = (<ProgramWithSourceTexts>oldProgram).sourceTexts.slice(0);
        }
        updater(newTexts);
        const host = createTestCompilerHost(newTexts, options.target, oldProgram);
        const program = <ProgramWithSourceTexts>createProgram(rootNames, options, host, oldProgram);
        program.sourceTexts = newTexts;
        program.host = host;
        return program;
    }

    export function updateProgramText(files: ReadonlyArray<NamedSourceText>, fileName: string, newProgramText: string) {
        const file = find(files, f => f.name === fileName)!;
        file.text = file.text.updateProgram(newProgramText);
    }

    function checkResolvedTypeDirective(expected: ResolvedTypeReferenceDirective, actual: ResolvedTypeReferenceDirective): boolean {
        if (!expected === !actual) {
            if (expected) {
                assert.equal(expected.resolvedFileName, actual.resolvedFileName, `'resolvedFileName': expected '${expected.resolvedFileName}' to be equal to '${actual.resolvedFileName}'`);
                assert.equal(expected.primary, actual.primary, `'primary': expected '${expected.primary}' to be equal to '${actual.primary}'`);
            }
            return true;
        }
        return false;
    }

    function checkCache<T>(caption: string, program: Program, fileName: string, expectedContent: Map<T>, getCache: (f: SourceFile) => Map<T>, entryChecker: (expected: T, original: T) => boolean): void {
        const file = program.getSourceFile(fileName);
        assert(file !== undefined, `cannot find file ${fileName}`);
        const cache = getCache(file);
        if (expectedContent === undefined) {
            assert(cache === undefined, `expected ${caption} to be undefined`);
        }
        else {
            assert(cache !== undefined, `expected ${caption} to be set`);
            assert(mapsAreEqual(expectedContent, cache, entryChecker), `contents of ${caption} did not match the expected contents.`);
        }
    }

    /** True if the maps have the same keys and values. */
    function mapsAreEqual<T>(left: Map<T>, right: Map<T>, valuesAreEqual?: (left: T, right: T) => boolean): boolean {
        if (left === right) return true;
        if (!left || !right) return false;
        const someInLeftHasNoMatch = forEachEntry(left, (leftValue, leftKey) => {
            if (!right.has(leftKey)) return true;
            const rightValue = right.get(leftKey);
            return !(valuesAreEqual ? valuesAreEqual(leftValue, rightValue) : leftValue === rightValue);
        });
        if (someInLeftHasNoMatch) return false;
        const someInRightHasNoMatch = forEachKey(right, rightKey => !left.has(rightKey));
        return !someInRightHasNoMatch;
    }

    function checkResolvedModulesCache(program: Program, fileName: string, expectedContent: Map<ResolvedModule>): void {
        checkCache("resolved modules", program, fileName, expectedContent, f => f.resolvedModules, checkResolvedModule);
    }

    function checkResolvedTypeDirectivesCache(program: Program, fileName: string, expectedContent: Map<ResolvedTypeReferenceDirective>): void {
        checkCache("resolved type directives", program, fileName, expectedContent, f => f.resolvedTypeReferenceDirectiveNames, checkResolvedTypeDirective);
    }

    describe("Reuse program structure", () => {
        const target = ScriptTarget.Latest;
        const files: NamedSourceText[] = [
            {
                name: "a.ts", text: SourceText.New(
                    `
/// <reference path='b.ts'/>
/// <reference path='non-existing-file.ts'/>
/// <reference types="typerefs" />
`, "", `var x = 1`)
            },
            { name: "b.ts", text: SourceText.New(`/// <reference path='c.ts'/>`, "", `var y = 2`) },
            { name: "c.ts", text: SourceText.New("", "", `var z = 1;`) },
            { name: "types/typerefs/index.d.ts", text: SourceText.New("", "", `declare let z: number;`) },
        ];

        it("successful if change does not affect imports", () => {
            const program1 = newProgram(files, ["a.ts"], { target });
            const program2 = updateProgram(program1, ["a.ts"], { target }, files => {
                files[0].text = files[0].text.updateProgram("var x = 100");
            });
            assert.equal(program1.structureIsReused, StructureIsReused.Completely);
            const program1Diagnostics = program1.getSemanticDiagnostics(program1.getSourceFile("a.ts"));
            const program2Diagnostics = program2.getSemanticDiagnostics(program1.getSourceFile("a.ts"));
            assert.equal(program1Diagnostics.length, program2Diagnostics.length);
        });

        it("successful if change does not affect type reference directives", () => {
            const program1 = newProgram(files, ["a.ts"], { target });
            const program2 = updateProgram(program1, ["a.ts"], { target }, files => {
                files[0].text = files[0].text.updateProgram("var x = 100");
            });
            assert.equal(program1.structureIsReused, StructureIsReused.Completely);
            const program1Diagnostics = program1.getSemanticDiagnostics(program1.getSourceFile("a.ts"));
            const program2Diagnostics = program2.getSemanticDiagnostics(program1.getSourceFile("a.ts"));
            assert.equal(program1Diagnostics.length, program2Diagnostics.length);
        });

        it("fails if change affects tripleslash references", () => {
            const program1 = newProgram(files, ["a.ts"], { target });
            updateProgram(program1, ["a.ts"], { target }, files => {
                const newReferences = `/// <reference path='b.ts'/>
                /// <reference path='c.ts'/>
                `;
                files[0].text = files[0].text.updateReferences(newReferences);
            });
            assert.equal(program1.structureIsReused, StructureIsReused.SafeModules);
        });

        it("fails if change affects type references", () => {
            const program1 = newProgram(files, ["a.ts"], { types: ["a"] });
            updateProgram(program1, ["a.ts"], { types: ["b"] }, noop);
            assert.equal(program1.structureIsReused, StructureIsReused.Not);
        });

        it("succeeds if change doesn't affect type references", () => {
            const program1 = newProgram(files, ["a.ts"], { types: ["a"] });
            updateProgram(program1, ["a.ts"], { types: ["a"] }, noop);
            assert.equal(program1.structureIsReused, StructureIsReused.Completely);
        });

        it("fails if change affects imports", () => {
            const program1 = newProgram(files, ["a.ts"], { target });
            updateProgram(program1, ["a.ts"], { target }, files => {
                files[2].text = files[2].text.updateImportsAndExports("import x from 'b'");
            });
            assert.equal(program1.structureIsReused, StructureIsReused.SafeModules);
        });

        it("fails if change affects type directives", () => {
            const program1 = newProgram(files, ["a.ts"], { target });
            updateProgram(program1, ["a.ts"], { target }, files => {
                const newReferences = `
/// <reference path='b.ts'/>
/// <reference path='non-existing-file.ts'/>
/// <reference types="typerefs1" />`;
                files[0].text = files[0].text.updateReferences(newReferences);
            });
            assert.equal(program1.structureIsReused, StructureIsReused.SafeModules);
        });

        it("fails if module kind changes", () => {
            const program1 = newProgram(files, ["a.ts"], { target, module: ModuleKind.CommonJS });
            updateProgram(program1, ["a.ts"], { target, module: ModuleKind.AMD }, noop);
            assert.equal(program1.structureIsReused, StructureIsReused.Not);
        });

        it("fails if rootdir changes", () => {
            const program1 = newProgram(files, ["a.ts"], { target, module: ModuleKind.CommonJS, rootDir: "/a/b" });
            updateProgram(program1, ["a.ts"], { target, module: ModuleKind.CommonJS, rootDir: "/a/c" }, noop);
            assert.equal(program1.structureIsReused, StructureIsReused.Not);
        });

        it("fails if config path changes", () => {
            const program1 = newProgram(files, ["a.ts"], { target, module: ModuleKind.CommonJS, configFilePath: "/a/b/tsconfig.json" });
            updateProgram(program1, ["a.ts"], { target, module: ModuleKind.CommonJS, configFilePath: "/a/c/tsconfig.json" }, noop);
            assert.equal(program1.structureIsReused, StructureIsReused.Not);
        });

        it("succeeds if missing files remain missing", () => {
            const options: CompilerOptions = { target, noLib: true };

            const program1 = newProgram(files, ["a.ts"], options);
            assert(program1.getMissingFilePaths().length !== 0);

            const program2 = updateProgram(program1, ["a.ts"], options, noop);
            assert.deepEqual(program1.getMissingFilePaths(), program2.getMissingFilePaths());

            assert.equal(StructureIsReused.Completely, program1.structureIsReused);
        });

        it("fails if missing file is created", () => {
            const options: CompilerOptions = { target, noLib: true };

            const program1 = newProgram(files, ["a.ts"], options);
            assert(program1.getMissingFilePaths().length !== 0);

            const newTexts: NamedSourceText[] = files.concat([{ name: "non-existing-file.ts", text: SourceText.New("", "", `var x = 1`) }]);
            const program2 = updateProgram(program1, ["a.ts"], options, noop, newTexts);
            assert.lengthOf(program2.getMissingFilePaths(), 0);

            assert.equal(StructureIsReused.Not, program1.structureIsReused);
        });

        it("resolution cache follows imports", () => {
            (<any>Error).stackTraceLimit = Infinity;

            const files = [
                { name: "a.ts", text: SourceText.New("", "import {_} from 'b'", "var x = 1") },
                { name: "b.ts", text: SourceText.New("", "", "var y = 2") },
            ];
            const options: CompilerOptions = { target };

            const program1 = newProgram(files, ["a.ts"], options);
            checkResolvedModulesCache(program1, "a.ts", createMapFromTemplate({ b: createResolvedModule("b.ts") }));
            checkResolvedModulesCache(program1, "b.ts", /*expectedContent*/ undefined);

            const program2 = updateProgram(program1, ["a.ts"], options, files => {
                files[0].text = files[0].text.updateProgram("var x = 2");
            });
            assert.equal(program1.structureIsReused, StructureIsReused.Completely);

            // content of resolution cache should not change
            checkResolvedModulesCache(program1, "a.ts", createMapFromTemplate({ b: createResolvedModule("b.ts") }));
            checkResolvedModulesCache(program1, "b.ts", /*expectedContent*/ undefined);

            // imports has changed - program is not reused
            const program3 = updateProgram(program2, ["a.ts"], options, files => {
                files[0].text = files[0].text.updateImportsAndExports("");
            });
            assert.equal(program2.structureIsReused, StructureIsReused.SafeModules);
            checkResolvedModulesCache(program3, "a.ts", /*expectedContent*/ undefined);

            const program4 = updateProgram(program3, ["a.ts"], options, files => {
                const newImports = `import x from 'b'
                import y from 'c'
                `;
                files[0].text = files[0].text.updateImportsAndExports(newImports);
            });
            assert.equal(program3.structureIsReused, StructureIsReused.SafeModules);
            checkResolvedModulesCache(program4, "a.ts", createMapFromTemplate({ b: createResolvedModule("b.ts"), c: undefined }));
        });

        it("set the resolvedImports after re-using an ambient external module declaration", () => {
            const files = [
                { name: "/a.ts", text: SourceText.New("", "", 'import * as a from "a";') },
                { name: "/types/zzz/index.d.ts", text: SourceText.New("", "", 'declare module "a" { }') },
            ];
            const options: CompilerOptions = { target, typeRoots: ["/types"] };
            const program1 = newProgram(files, ["/a.ts"], options);
            const program2 = updateProgram(program1, ["/a.ts"], options, files => {
                files[0].text = files[0].text.updateProgram('import * as aa from "a";');
            });
            assert.isDefined(program2.getSourceFile("/a.ts").resolvedModules.get("a"), "'a' is not an unresolved module after re-use");
        });

        it("resolved type directives cache follows type directives", () => {
            const files = [
                { name: "/a.ts", text: SourceText.New("/// <reference types='typedefs'/>", "", "var x = $") },
                { name: "/types/typedefs/index.d.ts", text: SourceText.New("", "", "declare var $: number") },
            ];
            const options: CompilerOptions = { target, typeRoots: ["/types"] };

            const program1 = newProgram(files, ["/a.ts"], options);
            checkResolvedTypeDirectivesCache(program1, "/a.ts", createMapFromTemplate({ typedefs: { resolvedFileName: "/types/typedefs/index.d.ts", primary: true } }));
            checkResolvedTypeDirectivesCache(program1, "/types/typedefs/index.d.ts", /*expectedContent*/ undefined);

            const program2 = updateProgram(program1, ["/a.ts"], options, files => {
                files[0].text = files[0].text.updateProgram("var x = 2");
            });
            assert.equal(program1.structureIsReused, StructureIsReused.Completely);

            // content of resolution cache should not change
            checkResolvedTypeDirectivesCache(program1, "/a.ts", createMapFromTemplate({ typedefs: { resolvedFileName: "/types/typedefs/index.d.ts", primary: true } }));
            checkResolvedTypeDirectivesCache(program1, "/types/typedefs/index.d.ts", /*expectedContent*/ undefined);

            // type reference directives has changed - program is not reused
            const program3 = updateProgram(program2, ["/a.ts"], options, files => {
                files[0].text = files[0].text.updateReferences("");
            });

            assert.equal(program2.structureIsReused, StructureIsReused.SafeModules);
            checkResolvedTypeDirectivesCache(program3, "/a.ts", /*expectedContent*/ undefined);

            updateProgram(program3, ["/a.ts"], options, files => {
                const newReferences = `/// <reference types="typedefs"/>
                /// <reference types="typedefs2"/>
                `;
                files[0].text = files[0].text.updateReferences(newReferences);
            });
            assert.equal(program3.structureIsReused, StructureIsReused.SafeModules);
            checkResolvedTypeDirectivesCache(program1, "/a.ts", createMapFromTemplate({ typedefs: { resolvedFileName: "/types/typedefs/index.d.ts", primary: true } }));
        });

        it("fetches imports after npm install", () => {
            const file1Ts = { name: "file1.ts", text: SourceText.New("", `import * as a from "a";`, "const myX: number = a.x;") };
            const file2Ts = { name: "file2.ts", text: SourceText.New("", "", "") };
            const indexDTS = { name: "node_modules/a/index.d.ts", text: SourceText.New("", "export declare let x: number;", "") };
            const options: CompilerOptions = { target: ScriptTarget.ES2015, traceResolution: true, moduleResolution: ModuleResolutionKind.NodeJs };
            const rootFiles = [file1Ts, file2Ts];
            const filesAfterNpmInstall = [file1Ts, file2Ts, indexDTS];

            const initialProgram = newProgram(rootFiles, rootFiles.map(f => f.name), options);
            {
                assert.deepEqual(initialProgram.host.getTrace(),
                    [
                        "======== Resolving module 'a' from 'file1.ts'. ========",
                        "Explicitly specified module resolution kind: 'NodeJs'.",
                        "Loading module 'a' from 'node_modules' folder, target file type 'TypeScript'.",
                        "File 'node_modules/a/package.json' does not exist.",
                        "File 'node_modules/a.ts' does not exist.",
                        "File 'node_modules/a.tsx' does not exist.",
                        "File 'node_modules/a.d.ts' does not exist.",
                        "File 'node_modules/a/index.ts' does not exist.",
                        "File 'node_modules/a/index.tsx' does not exist.",
                        "File 'node_modules/a/index.d.ts' does not exist.",
                        "File 'node_modules/@types/a/package.json' does not exist.",
                        "File 'node_modules/@types/a.d.ts' does not exist.",
                        "File 'node_modules/@types/a/index.d.ts' does not exist.",
                        "Loading module 'a' from 'node_modules' folder, target file type 'JavaScript'.",
                        "File 'node_modules/a/package.json' does not exist.",
                        "File 'node_modules/a.js' does not exist.",
                        "File 'node_modules/a.jsx' does not exist.",
                        "File 'node_modules/a/index.js' does not exist.",
                        "File 'node_modules/a/index.jsx' does not exist.",
                        "======== Module name 'a' was not resolved. ========"
                    ],
                    "initialProgram: execute module resolution normally.");

                const initialProgramDiagnostics = initialProgram.getSemanticDiagnostics(initialProgram.getSourceFile("file1.ts"));
                assert.lengthOf(initialProgramDiagnostics, 1, `initialProgram: import should fail.`);
            }

            const afterNpmInstallProgram = updateProgram(initialProgram, rootFiles.map(f => f.name), options, f => {
                f[1].text = f[1].text.updateReferences(`/// <reference no-default-lib="true"/>`);
            }, filesAfterNpmInstall);
            {
                assert.deepEqual(afterNpmInstallProgram.host.getTrace(),
                    [
                        "======== Resolving module 'a' from 'file1.ts'. ========",
                        "Explicitly specified module resolution kind: 'NodeJs'.",
                        "Loading module 'a' from 'node_modules' folder, target file type 'TypeScript'.",
                        "File 'node_modules/a/package.json' does not exist.",
                        "File 'node_modules/a.ts' does not exist.",
                        "File 'node_modules/a.tsx' does not exist.",
                        "File 'node_modules/a.d.ts' does not exist.",
                        "File 'node_modules/a/index.ts' does not exist.",
                        "File 'node_modules/a/index.tsx' does not exist.",
                        "File 'node_modules/a/index.d.ts' exist - use it as a name resolution result.",
                        "======== Module name 'a' was successfully resolved to 'node_modules/a/index.d.ts'. ========"
                    ],
                    "afterNpmInstallProgram: execute module resolution normally.");

                const afterNpmInstallProgramDiagnostics = afterNpmInstallProgram.getSemanticDiagnostics(afterNpmInstallProgram.getSourceFile("file1.ts"));
                assert.lengthOf(afterNpmInstallProgramDiagnostics, 0, `afterNpmInstallProgram: program is well-formed with import.`);
            }
        });

        it("can reuse ambient module declarations from non-modified files", () => {
            const files = [
                { name: "/a/b/app.ts", text: SourceText.New("", "import * as fs from 'fs'", "") },
                { name: "/a/b/node.d.ts", text: SourceText.New("", "", "declare module 'fs' {}") }
            ];
            const options = { target: ScriptTarget.ES2015, traceResolution: true };
            const program = newProgram(files, files.map(f => f.name), options);
            assert.deepEqual(program.host.getTrace(),
                [
                    "======== Resolving module 'fs' from '/a/b/app.ts'. ========",
                    "Module resolution kind is not specified, using 'Classic'.",
                    "File '/a/b/fs.ts' does not exist.",
                    "File '/a/b/fs.tsx' does not exist.",
                    "File '/a/b/fs.d.ts' does not exist.",
                    "File '/a/fs.ts' does not exist.",
                    "File '/a/fs.tsx' does not exist.",
                    "File '/a/fs.d.ts' does not exist.",
                    "File '/fs.ts' does not exist.",
                    "File '/fs.tsx' does not exist.",
                    "File '/fs.d.ts' does not exist.",
                    "File '/a/b/node_modules/@types/fs/package.json' does not exist.",
                    "File '/a/b/node_modules/@types/fs.d.ts' does not exist.",
                    "File '/a/b/node_modules/@types/fs/index.d.ts' does not exist.",
                    "File '/a/node_modules/@types/fs/package.json' does not exist.",
                    "File '/a/node_modules/@types/fs.d.ts' does not exist.",
                    "File '/a/node_modules/@types/fs/index.d.ts' does not exist.",
                    "File '/node_modules/@types/fs/package.json' does not exist.",
                    "File '/node_modules/@types/fs.d.ts' does not exist.",
                    "File '/node_modules/@types/fs/index.d.ts' does not exist.",
                    "File '/a/b/fs.js' does not exist.",
                    "File '/a/b/fs.jsx' does not exist.",
                    "File '/a/fs.js' does not exist.",
                    "File '/a/fs.jsx' does not exist.",
                    "File '/fs.js' does not exist.",
                    "File '/fs.jsx' does not exist.",
                    "======== Module name 'fs' was not resolved. ========",
                ], "should look for 'fs'");

            const program2 = updateProgram(program, program.getRootFileNames(), options, f => {
                f[0].text = f[0].text.updateProgram("var x = 1;");
            });
            assert.deepEqual(program2.host.getTrace(), [
                "Module 'fs' was resolved as ambient module declared in '/a/b/node.d.ts' since this file was not modified."
            ], "should reuse 'fs' since node.d.ts was not changed");

            const program3 = updateProgram(program2, program2.getRootFileNames(), options, f => {
                f[0].text = f[0].text.updateProgram("var y = 1;");
                f[1].text = f[1].text.updateProgram("declare var process: any");
            });
            assert.deepEqual(program3.host.getTrace(),
                [
                    "======== Resolving module 'fs' from '/a/b/app.ts'. ========",
                    "Module resolution kind is not specified, using 'Classic'.",
                    "File '/a/b/fs.ts' does not exist.",
                    "File '/a/b/fs.tsx' does not exist.",
                    "File '/a/b/fs.d.ts' does not exist.",
                    "File '/a/fs.ts' does not exist.",
                    "File '/a/fs.tsx' does not exist.",
                    "File '/a/fs.d.ts' does not exist.",
                    "File '/fs.ts' does not exist.",
                    "File '/fs.tsx' does not exist.",
                    "File '/fs.d.ts' does not exist.",
                    "File '/a/b/node_modules/@types/fs/package.json' does not exist.",
                    "File '/a/b/node_modules/@types/fs.d.ts' does not exist.",
                    "File '/a/b/node_modules/@types/fs/index.d.ts' does not exist.",
                    "File '/a/node_modules/@types/fs/package.json' does not exist.",
                    "File '/a/node_modules/@types/fs.d.ts' does not exist.",
                    "File '/a/node_modules/@types/fs/index.d.ts' does not exist.",
                    "File '/node_modules/@types/fs/package.json' does not exist.",
                    "File '/node_modules/@types/fs.d.ts' does not exist.",
                    "File '/node_modules/@types/fs/index.d.ts' does not exist.",
                    "File '/a/b/fs.js' does not exist.",
                    "File '/a/b/fs.jsx' does not exist.",
                    "File '/a/fs.js' does not exist.",
                    "File '/a/fs.jsx' does not exist.",
                    "File '/fs.js' does not exist.",
                    "File '/fs.jsx' does not exist.",
                    "======== Module name 'fs' was not resolved. ========",
                ], "should look for 'fs' again since node.d.ts was changed");
        });

        it("can reuse module resolutions from non-modified files", () => {
            const files = [
                { name: "a1.ts", text: SourceText.New("", "", "let x = 1;") },
                { name: "a2.ts", text: SourceText.New("", "", "let x = 1;") },
                { name: "b1.ts", text: SourceText.New("", "export class B { x: number; }", "") },
                { name: "b2.ts", text: SourceText.New("", "export class B { x: number; }", "") },
                { name: "node_modules/@types/typerefs1/index.d.ts", text: SourceText.New("", "", "declare let z: string;") },
                { name: "node_modules/@types/typerefs2/index.d.ts", text: SourceText.New("", "", "declare let z: string;") },
                {
                    name: "f1.ts",
                    text:
                    SourceText.New(
                        `/// <reference path="a1.ts"/>${newLine}/// <reference types="typerefs1"/>${newLine}/// <reference no-default-lib="true"/>`,
                        `import { B } from './b1';${newLine}export let BB = B;`,
                        "declare module './b1' { interface B { y: string; } }")
                },
                {
                    name: "f2.ts",
                    text: SourceText.New(
                        `/// <reference path="a2.ts"/>${newLine}/// <reference types="typerefs2"/>`,
                        `import { B } from './b2';${newLine}import { BB } from './f1';`,
                        "(new BB).x; (new BB).y;")
                },
            ];

            const options: CompilerOptions = { target: ScriptTarget.ES2015, traceResolution: true, moduleResolution: ModuleResolutionKind.Classic };
            const program1 = newProgram(files, files.map(f => f.name), options);
            let expectedErrors = 0;
            {
                assert.deepEqual(program1.host.getTrace(),
                    [
                        "======== Resolving type reference directive 'typerefs1', containing file 'f1.ts', root directory 'node_modules/@types'. ========",
                        "Resolving with primary search path 'node_modules/@types'.",
                        "File 'node_modules/@types/typerefs1/package.json' does not exist.",
                        "File 'node_modules/@types/typerefs1/index.d.ts' exist - use it as a name resolution result.",
                        "======== Type reference directive 'typerefs1' was successfully resolved to 'node_modules/@types/typerefs1/index.d.ts', primary: true. ========",
                        "======== Resolving module './b1' from 'f1.ts'. ========",
                        "Explicitly specified module resolution kind: 'Classic'.",
                        "File 'b1.ts' exist - use it as a name resolution result.",
                        "======== Module name './b1' was successfully resolved to 'b1.ts'. ========",
                        "======== Resolving type reference directive 'typerefs2', containing file 'f2.ts', root directory 'node_modules/@types'. ========",
                        "Resolving with primary search path 'node_modules/@types'.",
                        "File 'node_modules/@types/typerefs2/package.json' does not exist.",
                        "File 'node_modules/@types/typerefs2/index.d.ts' exist - use it as a name resolution result.",
                        "======== Type reference directive 'typerefs2' was successfully resolved to 'node_modules/@types/typerefs2/index.d.ts', primary: true. ========",
                        "======== Resolving module './b2' from 'f2.ts'. ========",
                        "Explicitly specified module resolution kind: 'Classic'.",
                        "File 'b2.ts' exist - use it as a name resolution result.",
                        "======== Module name './b2' was successfully resolved to 'b2.ts'. ========",
                        "======== Resolving module './f1' from 'f2.ts'. ========",
                        "Explicitly specified module resolution kind: 'Classic'.",
                        "File 'f1.ts' exist - use it as a name resolution result.",
                        "======== Module name './f1' was successfully resolved to 'f1.ts'. ========"
                    ],
                    "program1: execute module resolution normally.");

                const program1Diagnostics = program1.getSemanticDiagnostics(program1.getSourceFile("f2.ts"));
                assert.lengthOf(program1Diagnostics, expectedErrors, `initial program should be well-formed`);
            }
            const indexOfF1 = 6;
            const program2 = updateProgram(program1, program1.getRootFileNames(), options, f => {
                const newSourceText = f[indexOfF1].text.updateReferences(`/// <reference path="a1.ts"/>${newLine}/// <reference types="typerefs1"/>`);
                f[indexOfF1] = { name: "f1.ts", text: newSourceText };
            });

            {
                const program2Diagnostics = program2.getSemanticDiagnostics(program2.getSourceFile("f2.ts"));
                assert.lengthOf(program2Diagnostics, expectedErrors, `removing no-default-lib shouldn't affect any types used.`);

                assert.deepEqual(program2.host.getTrace(), [
                    "======== Resolving type reference directive 'typerefs1', containing file 'f1.ts', root directory 'node_modules/@types'. ========",
                    "Resolving with primary search path 'node_modules/@types'.",
                    "File 'node_modules/@types/typerefs1/package.json' does not exist.",
                    "File 'node_modules/@types/typerefs1/index.d.ts' exist - use it as a name resolution result.",
                    "======== Type reference directive 'typerefs1' was successfully resolved to 'node_modules/@types/typerefs1/index.d.ts', primary: true. ========",
                    "======== Resolving module './b1' from 'f1.ts'. ========",
                    "Explicitly specified module resolution kind: 'Classic'.",
                    "File 'b1.ts' exist - use it as a name resolution result.",
                    "======== Module name './b1' was successfully resolved to 'b1.ts'. ========",
                    "======== Resolving type reference directive 'typerefs2', containing file 'f2.ts', root directory 'node_modules/@types'. ========",
                    "Resolving with primary search path 'node_modules/@types'.",
                    "File 'node_modules/@types/typerefs2/package.json' does not exist.",
                    "File 'node_modules/@types/typerefs2/index.d.ts' exist - use it as a name resolution result.",
                    "======== Type reference directive 'typerefs2' was successfully resolved to 'node_modules/@types/typerefs2/index.d.ts', primary: true. ========",
                    "Reusing resolution of module './b2' to file 'f2.ts' from old program.",
                    "Reusing resolution of module './f1' to file 'f2.ts' from old program."
                ], "program2: reuse module resolutions in f2 since it is unchanged");
            }

            const program3 = updateProgram(program2, program2.getRootFileNames(), options, f => {
                const newSourceText = f[indexOfF1].text.updateReferences(`/// <reference path="a1.ts"/>`);
                f[indexOfF1] = { name: "f1.ts", text: newSourceText };
            });

            {
                const program3Diagnostics = program3.getSemanticDiagnostics(program3.getSourceFile("f2.ts"));
                assert.lengthOf(program3Diagnostics, expectedErrors, `typerefs2 was unused, so diagnostics should be unaffected.`);

                assert.deepEqual(program3.host.getTrace(), [
                    "======== Resolving module './b1' from 'f1.ts'. ========",
                    "Explicitly specified module resolution kind: 'Classic'.",
                    "File 'b1.ts' exist - use it as a name resolution result.",
                    "======== Module name './b1' was successfully resolved to 'b1.ts'. ========",
                    "======== Resolving type reference directive 'typerefs2', containing file 'f2.ts', root directory 'node_modules/@types'. ========",
                    "Resolving with primary search path 'node_modules/@types'.",
                    "File 'node_modules/@types/typerefs2/package.json' does not exist.",
                    "File 'node_modules/@types/typerefs2/index.d.ts' exist - use it as a name resolution result.",
                    "======== Type reference directive 'typerefs2' was successfully resolved to 'node_modules/@types/typerefs2/index.d.ts', primary: true. ========",
                    "Reusing resolution of module './b2' to file 'f2.ts' from old program.",
                    "Reusing resolution of module './f1' to file 'f2.ts' from old program."
                ], "program3: reuse module resolutions in f2 since it is unchanged");
            }


            const program4 = updateProgram(program3, program3.getRootFileNames(), options, f => {
                const newSourceText = f[indexOfF1].text.updateReferences("");
                f[indexOfF1] = { name: "f1.ts", text: newSourceText };
            });

            {
                const program4Diagnostics = program4.getSemanticDiagnostics(program4.getSourceFile("f2.ts"));
                assert.lengthOf(program4Diagnostics, expectedErrors, `a1.ts was unused, so diagnostics should be unaffected.`);

                assert.deepEqual(program4.host.getTrace(), [
                    "======== Resolving module './b1' from 'f1.ts'. ========",
                    "Explicitly specified module resolution kind: 'Classic'.",
                    "File 'b1.ts' exist - use it as a name resolution result.",
                    "======== Module name './b1' was successfully resolved to 'b1.ts'. ========",
                    "======== Resolving type reference directive 'typerefs2', containing file 'f2.ts', root directory 'node_modules/@types'. ========",
                    "Resolving with primary search path 'node_modules/@types'.",
                    "File 'node_modules/@types/typerefs2/package.json' does not exist.",
                    "File 'node_modules/@types/typerefs2/index.d.ts' exist - use it as a name resolution result.",
                    "======== Type reference directive 'typerefs2' was successfully resolved to 'node_modules/@types/typerefs2/index.d.ts', primary: true. ========",
                    "Reusing resolution of module './b2' to file 'f2.ts' from old program.",
                    "Reusing resolution of module './f1' to file 'f2.ts' from old program."
                ], "program_4: reuse module resolutions in f2 since it is unchanged");
            }

            const program5 = updateProgram(program4, program4.getRootFileNames(), options, f => {
                const newSourceText = f[indexOfF1].text.updateImportsAndExports(`import { B } from './b1';`);
                f[indexOfF1] = { name: "f1.ts", text: newSourceText };
            });

            {
                const program5Diagnostics = program5.getSemanticDiagnostics(program5.getSourceFile("f2.ts"));
                assert.lengthOf(program5Diagnostics, ++expectedErrors, `import of BB in f1 fails. BB is of type any. Add one error`);

                assert.deepEqual(program5.host.getTrace(), [
                    "======== Resolving module './b1' from 'f1.ts'. ========",
                    "Explicitly specified module resolution kind: 'Classic'.",
                    "File 'b1.ts' exist - use it as a name resolution result.",
                    "======== Module name './b1' was successfully resolved to 'b1.ts'. ========"
                ], "program_5: exports do not affect program structure, so f2's resolutions are silently reused.");
            }

            const program6 = updateProgram(program5, program5.getRootFileNames(), options, f => {
                const newSourceText = f[indexOfF1].text.updateProgram("");
                f[indexOfF1] = { name: "f1.ts", text: newSourceText };
            });

            {
                const program6Diagnostics = program6.getSemanticDiagnostics(program6.getSourceFile("f2.ts"));
                assert.lengthOf(program6Diagnostics, expectedErrors, `import of BB in f1 fails.`);

                assert.deepEqual(program6.host.getTrace(), [
                    "======== Resolving module './b1' from 'f1.ts'. ========",
                    "Explicitly specified module resolution kind: 'Classic'.",
                    "File 'b1.ts' exist - use it as a name resolution result.",
                    "======== Module name './b1' was successfully resolved to 'b1.ts'. ========",
                    "======== Resolving type reference directive 'typerefs2', containing file 'f2.ts', root directory 'node_modules/@types'. ========",
                    "Resolving with primary search path 'node_modules/@types'.",
                    "File 'node_modules/@types/typerefs2/package.json' does not exist.",
                    "File 'node_modules/@types/typerefs2/index.d.ts' exist - use it as a name resolution result.",
                    "======== Type reference directive 'typerefs2' was successfully resolved to 'node_modules/@types/typerefs2/index.d.ts', primary: true. ========",
                    "Reusing resolution of module './b2' to file 'f2.ts' from old program.",
                    "Reusing resolution of module './f1' to file 'f2.ts' from old program."
                ], "program_6: reuse module resolutions in f2 since it is unchanged");
            }

            const program7 = updateProgram(program6, program6.getRootFileNames(), options, f => {
                const newSourceText = f[indexOfF1].text.updateImportsAndExports("");
                f[indexOfF1] = { name: "f1.ts", text: newSourceText };
            });

            {
                const program7Diagnostics = program7.getSemanticDiagnostics(program7.getSourceFile("f2.ts"));
                assert.lengthOf(program7Diagnostics, expectedErrors, `removing import is noop with respect to program, so no change in diagnostics.`);

                assert.deepEqual(program7.host.getTrace(), [
                    "======== Resolving type reference directive 'typerefs2', containing file 'f2.ts', root directory 'node_modules/@types'. ========",
                    "Resolving with primary search path 'node_modules/@types'.",
                    "File 'node_modules/@types/typerefs2/package.json' does not exist.",
                    "File 'node_modules/@types/typerefs2/index.d.ts' exist - use it as a name resolution result.",
                    "======== Type reference directive 'typerefs2' was successfully resolved to 'node_modules/@types/typerefs2/index.d.ts', primary: true. ========",
                    "Reusing resolution of module './b2' to file 'f2.ts' from old program.",
                    "Reusing resolution of module './f1' to file 'f2.ts' from old program."
                ], "program_7 should reuse module resolutions in f2 since it is unchanged");
            }
        });

        describe("redirects", () => {
            const axIndex = "/node_modules/a/node_modules/x/index.d.ts";
            const axPackage = "/node_modules/a/node_modules/x/package.json";
            const bxIndex = "/node_modules/b/node_modules/x/index.d.ts";
            const bxPackage = "/node_modules/b/node_modules/x/package.json";
            const root = "/a.ts";
            const compilerOptions = { target, moduleResolution: ModuleResolutionKind.NodeJs };

            function createRedirectProgram(options?: { bText: string, bVersion: string }): ProgramWithSourceTexts {
                const files: NamedSourceText[] = [
                    {
                        name: "/node_modules/a/index.d.ts",
                        text: SourceText.New("", 'import X from "x";', "export function a(x: X): void;"),
                    },
                    {
                        name: axIndex,
                        text: SourceText.New("", "", "export default class X { private x: number; }"),
                    },
                    {
                        name: axPackage,
                        text: SourceText.New("", "", JSON.stringify({ name: "x", version: "1.2.3" })),
                    },
                    {
                        name: "/node_modules/b/index.d.ts",
                        text: SourceText.New("", 'import X from "x";', "export const b: X;"),
                    },
                    {
                        name: bxIndex,
                        text: SourceText.New("", "", options ? options.bText : "export default class X { private x: number; }"),
                    },
                    {
                        name: bxPackage,
                        text: SourceText.New("", "", JSON.stringify({ name: "x", version: options ? options.bVersion : "1.2.3" })),
                    },
                    {
                        name: root,
                        text: SourceText.New("", 'import { a } from "a"; import { b } from "b";', "a(b)"),
                    },
                ];

                return newProgram(files, [root], compilerOptions);
            }

            function updateRedirectProgram(program: ProgramWithSourceTexts, updater: (files: NamedSourceText[]) => void): ProgramWithSourceTexts {
                return updateProgram(program, [root], compilerOptions, updater);
            }

            it("No changes -> redirect not broken", () => {
                const program1 = createRedirectProgram();

                const program2 = updateRedirectProgram(program1, files => {
                    updateProgramText(files, root, "const x = 1;");
                });
                assert.equal(program1.structureIsReused, StructureIsReused.Completely);
                assert.lengthOf(program2.getSemanticDiagnostics(), 0);
            });

            it("Target changes -> redirect broken", () => {
                const program1 = createRedirectProgram();
                assert.lengthOf(program1.getSemanticDiagnostics(), 0);

                const program2 = updateRedirectProgram(program1, files => {
                    updateProgramText(files, axIndex, "export default class X { private x: number; private y: number; }");
                    updateProgramText(files, axPackage, JSON.stringify('{ name: "x", version: "1.2.4" }'));
                });
                assert.equal(program1.structureIsReused, StructureIsReused.Not);
                assert.lengthOf(program2.getSemanticDiagnostics(), 1);
            });

            it("Underlying changes -> redirect broken", () => {
                const program1 = createRedirectProgram();

                const program2 = updateRedirectProgram(program1, files => {
                    updateProgramText(files, bxIndex, "export default class X { private x: number; private y: number; }");
                    updateProgramText(files, bxPackage, JSON.stringify({ name: "x", version: "1.2.4" }));
                });
                assert.equal(program1.structureIsReused, StructureIsReused.Not);
                assert.lengthOf(program2.getSemanticDiagnostics(), 1);
            });

            it("Previously duplicate packages -> program structure not reused", () => {
                const program1 = createRedirectProgram({ bVersion: "1.2.4", bText: "export = class X { private x: number; }" });

                const program2 = updateRedirectProgram(program1, files => {
                    updateProgramText(files, bxIndex, "export default class X { private x: number; }");
                    updateProgramText(files, bxPackage, JSON.stringify({ name: "x", version: "1.2.3" }));
                });
                assert.equal(program1.structureIsReused, StructureIsReused.Not);
                assert.lengthOf(program2.getSemanticDiagnostics(), 0);
            });
        });
    });

    describe("host is optional", () => {
        it("should work if host is not provided", () => {
            createProgram([], {});
        });
    });

    import TestSystem = ts.TestFSWithWatch.TestServerHost;
    type FileOrFolder = ts.TestFSWithWatch.FileOrFolder;
    import createTestSystem = ts.TestFSWithWatch.createWatchedSystem;
    import libFile = ts.TestFSWithWatch.libFile;

    describe("isProgramUptoDate should return true when there is no change in compiler options and", () => {
        function verifyProgramIsUptoDate(
            program: Program,
            newRootFileNames: string[],
            newOptions: CompilerOptions
        ) {
            const actual = isProgramUptoDate(
                program, newRootFileNames, newOptions,
                path => program.getSourceFileByPath(path).version, /*fileExists*/ returnFalse,
                /*hasInvalidatedResolution*/ returnFalse,
                /*hasChangedAutomaticTypeDirectiveNames*/ false
            );
            assert(actual);
        }

        function duplicate(options: CompilerOptions): CompilerOptions;
        function duplicate(fileNames: string[]): string[];
        function duplicate(filesOrOptions: CompilerOptions | string[]) {
            return JSON.parse(JSON.stringify(filesOrOptions));
        }

        function createWatchingSystemHost(host: TestSystem) {
            return ts.createWatchingSystemHost(/*pretty*/ undefined, host);
        }

        function verifyProgramWithoutConfigFile(watchingSystemHost: WatchingSystemHost, rootFiles: string[], options: CompilerOptions) {
            const program = createWatchModeWithoutConfigFile(rootFiles, options, watchingSystemHost)();
            verifyProgramIsUptoDate(program, duplicate(rootFiles), duplicate(options));
        }

        function getConfigParseResult(watchingSystemHost: WatchingSystemHost, configFileName: string) {
            return parseConfigFile(configFileName, {}, watchingSystemHost.system, watchingSystemHost.reportDiagnostic, watchingSystemHost.reportWatchDiagnostic);
        }

        function verifyProgramWithConfigFile(watchingSystemHost: WatchingSystemHost, configFile: string) {
            const result = getConfigParseResult(watchingSystemHost, configFile);
            const program = createWatchModeWithConfigFile(result, {}, watchingSystemHost)();
            const { fileNames, options } = getConfigParseResult(watchingSystemHost, configFile);
            verifyProgramIsUptoDate(program, fileNames, options);
        }

        function verifyProgram(files: FileOrFolder[], rootFiles: string[], options: CompilerOptions, configFile: string) {
            const watchingSystemHost = createWatchingSystemHost(createTestSystem(files));
            verifyProgramWithoutConfigFile(watchingSystemHost, rootFiles, options);
            verifyProgramWithConfigFile(watchingSystemHost, configFile);
        }

        it("has empty options", () => {
            const file1: FileOrFolder = {
                path: "/a/b/file1.ts",
                content: "let x = 1"
            };
            const file2: FileOrFolder = {
                path: "/a/b/file2.ts",
                content: "let y = 1"
            };
            const configFile: FileOrFolder = {
                path: "/a/b/tsconfig.json",
                content: "{}"
            };
            verifyProgram([file1, file2, libFile, configFile], [file1.path, file2.path], {}, configFile.path);
        });

        it("has lib specified in the options", () => {
            const compilerOptions: CompilerOptions = { lib: ["es5", "es2015.promise"] };
            const app: FileOrFolder = {
                path: "/src/app.ts",
                content: "var x: Promise<string>;"
            };
            const configFile: FileOrFolder = {
                path: "/src/tsconfig.json",
                content: JSON.stringify({ compilerOptions })
            };
            const es5Lib: FileOrFolder = {
                path: "/compiler/lib.es5.d.ts",
                content: "declare const eval: any"
            };
            const es2015Promise: FileOrFolder = {
                path: "/compiler/lib.es2015.promise.d.ts",
                content: "declare class Promise<T> {}"
            };

            verifyProgram([app, configFile, es5Lib, es2015Promise], [app.path], compilerOptions, configFile.path);
        });

        it("has paths specified in the options", () => {
            const compilerOptions: CompilerOptions = {
                baseUrl: ".",
                paths: {
                    "*": [
                        "packages/mail/data/*",
                        "packages/styles/*",
                        "*"
                    ]
                }
            };
            const app: FileOrFolder = {
                path: "/src/packages/framework/app.ts",
                content: 'import classc from "module1/lib/file1";\
                          import classD from "module3/file3";\
                          let x = new classc();\
                          let y = new classD();'
            };
            const module1: FileOrFolder = {
                path: "/src/packages/mail/data/module1/lib/file1.ts",
                content: 'import classc from "module2/file2";export default classc;',
            };
            const module2: FileOrFolder = {
                path: "/src/packages/mail/data/module1/lib/module2/file2.ts",
                content: 'class classc { method2() { return "hello"; } }\nexport default classc',
            };
            const module3: FileOrFolder = {
                path: "/src/packages/styles/module3/file3.ts",
                content: "class classD { method() { return 10; } }\nexport default classD;"
            };
            const configFile: FileOrFolder = {
                path: "/src/tsconfig.json",
                content: JSON.stringify({ compilerOptions })
            };

            verifyProgram([app, module1, module2, module3, libFile, configFile], [app.path], compilerOptions, configFile.path);
        });

        it("has include paths specified in tsconfig file", () => {
            const compilerOptions: CompilerOptions = {
                baseUrl: ".",
                paths: {
                    "*": [
                        "packages/mail/data/*",
                        "packages/styles/*",
                        "*"
                    ]
                }
            };
            const app: FileOrFolder = {
                path: "/src/packages/framework/app.ts",
                content: 'import classc from "module1/lib/file1";\
                          import classD from "module3/file3";\
                          let x = new classc();\
                          let y = new classD();'
            };
            const module1: FileOrFolder = {
                path: "/src/packages/mail/data/module1/lib/file1.ts",
                content: 'import classc from "module2/file2";export default classc;',
            };
            const module2: FileOrFolder = {
                path: "/src/packages/mail/data/module1/lib/module2/file2.ts",
                content: 'class classc { method2() { return "hello"; } }\nexport default classc',
            };
            const module3: FileOrFolder = {
                path: "/src/packages/styles/module3/file3.ts",
                content: "class classD { method() { return 10; } }\nexport default classD;"
            };
            const configFile: FileOrFolder = {
                path: "/src/tsconfig.json",
                content: JSON.stringify({ compilerOptions, include: ["packages/**/ *.ts"] })
            };

            const watchingSystemHost = createWatchingSystemHost(createTestSystem([app, module1, module2, module3, libFile, configFile]));
            verifyProgramWithConfigFile(watchingSystemHost, configFile.path);
        });
    });
}