Configuration Inheritance

Jakefile.js

@@ -177,6 +177,7 @@ var harnessSources = harnessCoreSources.concat([
     "moduleResolution.ts",
     "tsconfigParsing.ts",
     "commandLineParsing.ts",
+    "configurationExtension.ts",
     "convertCompilerOptionsFromJson.ts",
     "convertTypingOptionsFromJson.ts",
     "tsserverProjectSystem.ts",

src/compiler/commandLineParser.ts

@@ -799,12 +799,45 @@ namespace ts {
       * @param basePath A root directory to resolve relative path entries in the config
       *    file to. e.g. outDir
       */
-    export function parseJsonConfigFileContent(json: any, host: ParseConfigHost, basePath: string, existingOptions: CompilerOptions = {}, configFileName?: string): ParsedCommandLine {
+    export function parseJsonConfigFileContent(json: any, host: ParseConfigHost, basePath: string, existingOptions: CompilerOptions = {}, configFileName?: string, resolutionStack: Path[] = []): ParsedCommandLine {
         const errors: Diagnostic[] = [];
-        const compilerOptions: CompilerOptions = convertCompilerOptionsFromJsonWorker(json["compilerOptions"], basePath, errors, configFileName);
-        const options = extend(existingOptions, compilerOptions);
+        const getCanonicalFileName = createGetCanonicalFileName(host.useCaseSensitiveFileNames);
+        const resolvedPath = toPath(configFileName || "", basePath, getCanonicalFileName);
+        if (resolutionStack.indexOf(resolvedPath) >= 0) {
+            return {
+                options: {},
+                fileNames: [],
+                typingOptions: {},
+                raw: json,
+                errors: [createCompilerDiagnostic(Diagnostics.Circularity_detected_while_resolving_configuration_Colon_0, [...resolutionStack, resolvedPath].join(" -> "))],
+                wildcardDirectories: {}
+            };
+        }
+
+        let options: CompilerOptions = convertCompilerOptionsFromJsonWorker(json["compilerOptions"], basePath, errors, configFileName);
         const typingOptions: TypingOptions = convertTypingOptionsFromJsonWorker(json["typingOptions"], basePath, errors, configFileName);
 
+        if (json["extends"]) {
+            let [include, exclude, files, baseOptions]: [string[], string[], string[], CompilerOptions] = [undefined, undefined, undefined, {}];
+            if (typeof json["extends"] === "string") {
+                [include, exclude, files, baseOptions] = (tryExtendsName(json["extends"]) || [include, exclude, files, baseOptions]);
+            }
+            else {
+                errors.push(createCompilerDiagnostic(Diagnostics.Compiler_option_0_requires_a_value_of_type_1, "extends", "string"));
+            }
+            if (include && !json["include"]) {
+                json["include"] = include;
+            }
+            if (exclude && !json["exclude"]) {
+                json["exclude"] = exclude;
+            }
+            if (files && !json["files"]) {
+                json["files"] = files;
+            }
+            options = assign({}, baseOptions, options);
+        }
+
+        options = extend(existingOptions, options);
         options.configFilePath = configFileName;
 
         const { fileNames, wildcardDirectories } = getFileNames(errors);
@@ -818,6 +851,39 @@ namespace ts {
             wildcardDirectories
         };
 
+        function tryExtendsName(extendedConfig: string): [string[], string[], string[], CompilerOptions] {
+            // If the path isn't a rooted or relative path, don't try to resolve it (we reserve the right to special case module-id like paths in the future)
+            if (!(isRootedDiskPath(extendedConfig) || startsWith(normalizeSlashes(extendedConfig), "./") || startsWith(normalizeSlashes(extendedConfig), "../"))) {
+                errors.push(createCompilerDiagnostic(Diagnostics.The_path_in_an_extends_options_must_be_relative_or_rooted));
+                return;
+            }
+            let extendedConfigPath = toPath(extendedConfig, basePath, getCanonicalFileName);
+            if (!host.fileExists(extendedConfigPath) && !endsWith(extendedConfigPath, ".json")) {
+                extendedConfigPath = `${extendedConfigPath}.json` as Path;
+                if (!host.fileExists(extendedConfigPath)) {
+                    errors.push(createCompilerDiagnostic(Diagnostics.File_0_does_not_exist, extendedConfig));
+                    return;
+                }
+            }
+            const extendedResult = readConfigFile(extendedConfigPath, path => host.readFile(path));
+            if (extendedResult.error) {
+                errors.push(extendedResult.error);
+                return;
+            }
+            const extendedDirname = getDirectoryPath(extendedConfigPath);
+            const relativeDifference = convertToRelativePath(extendedDirname, basePath, getCanonicalFileName);
+            const updatePath: (path: string) => string = path => isRootedDiskPath(path) ? path : combinePaths(relativeDifference, path);
+            // Merge configs (copy the resolution stack so it is never reused between branches in potential diamond-problem scenarios)
+            const result = parseJsonConfigFileContent(extendedResult.config, host, extendedDirname, /*existingOptions*/undefined, getBaseFileName(extendedConfigPath), resolutionStack.concat([resolvedPath]));
+            errors.push(...result.errors);
+            const [include, exclude, files] = map(["include", "exclude", "files"], key => {
+                if (!json[key] && extendedResult.config[key]) {
+                    return map(extendedResult.config[key], updatePath);
+                }
+            });
+            return [include, exclude, files, result.options];
+        }
+
         function getFileNames(errors: Diagnostic[]): ExpandResult {
             let fileNames: string[];
             if (hasProperty(json, "files")) {

src/compiler/core.ts

@@ -243,6 +243,20 @@ namespace ts {
         return result;
     }
 
+    export function mapObject<T, U>(object: MapLike<T>, f: (key: string, x: T) => [string, U]): MapLike<U> {
+        let result: MapLike<U>;
+        if (object) {
+            result = {};
+            for (const v of getOwnKeys(object)) {
+                const [key, value]: [string, U] = f(v, object[v]) || [undefined, undefined];
+                if (key !== undefined) {
+                    result[key] = value;
+                }
+            }
+        }
+        return result;
+    }
+
     export function concatenate<T>(array1: T[], array2: T[]): T[] {
         if (!array2 || !array2.length) return array1;
         if (!array1 || !array1.length) return array2;
@@ -464,6 +478,18 @@ namespace ts {
         }
     }
 
+    export function assign<T1 extends MapLike<{}>, T2, T3>(t: T1, arg1: T2, arg2: T3): T1 & T2 & T3;
+    export function assign<T1 extends MapLike<{}>, T2>(t: T1, arg1: T2): T1 & T2;
+    export function assign<T1 extends MapLike<{}>>(t: T1, ...args: any[]): any;
+    export function assign<T1 extends MapLike<{}>>(t: T1, ...args: any[]) {
+        for (const arg of args) {
+            for (const p of getOwnKeys(arg)) {
+                t[p] = arg[p];
+            }
+        }
+        return t;
+    }
+
     /**
      * Reduce the properties of a map.
      *

src/compiler/diagnosticMessages.json

@@ -3043,5 +3043,14 @@
     "Unknown typing option '{0}'.": {
         "category": "Error",
         "code": 17010
+    },
+
+    "Circularity detected while resolving configuration: {0}": {
+        "category": "Error",
+        "code": 18000
+    },
+    "The path in an 'extends' options must be relative or rooted.": {
+        "category": "Error",
+        "code": 18001
     }
 }

src/compiler/types.ts

@@ -1721,6 +1721,8 @@ namespace ts {
           * @param path The path to test.
           */
         fileExists(path: string): boolean;
+
+        readFile(path: string): string;
     }
 
     export interface WriteFileCallback {

src/harness/harness.ts

@@ -1754,7 +1754,8 @@ namespace Harness {
             const parseConfigHost: ts.ParseConfigHost = {
                 useCaseSensitiveFileNames: false,
                 readDirectory: (name) => [],
-                fileExists: (name) => true
+                fileExists: (name) => true,
+                readFile: (name) => ts.forEach(testUnitData, data => data.name.toLowerCase() === name.toLowerCase() ? data.content : undefined)
             };
 
             // check if project has tsconfig.json in the list of files

src/harness/projectsRunner.ts

@@ -222,6 +222,7 @@ class ProjectRunner extends RunnerBase {
                     useCaseSensitiveFileNames: Harness.IO.useCaseSensitiveFileNames(),
                     fileExists,
                     readDirectory,
+                    readFile
                 };
                 const configParseResult = ts.parseJsonConfigFileContent(configObject, configParseHost, ts.getDirectoryPath(configFileName), compilerOptions);
                 if (configParseResult.errors.length > 0) {
@@ -292,6 +293,10 @@ class ProjectRunner extends RunnerBase {
                 return Harness.IO.fileExists(getFileNameInTheProjectTest(fileName));
             }
 
+            function readFile(fileName: string): string {
+                return Harness.IO.readFile(getFileNameInTheProjectTest(fileName));
+            }
+
             function getSourceFileText(fileName: string): string {
                 let text: string = undefined;
                 try {

src/harness/rwcRunner.ts

@@ -79,6 +79,7 @@ namespace RWC {
                             useCaseSensitiveFileNames: Harness.IO.useCaseSensitiveFileNames(),
                             fileExists: Harness.IO.fileExists,
                             readDirectory: Harness.IO.readDirectory,
+                            readFile: Harness.IO.readFile
                         };
                         const configParseResult = ts.parseJsonConfigFileContent(parsedTsconfigFileContents.config, configParseHost, ts.getDirectoryPath(tsconfigFile.path));
                         fileNames = configParseResult.fileNames;

src/harness/tsconfig.json

@@ -86,6 +86,7 @@
         "./unittests/moduleResolution.ts",
         "./unittests/tsconfigParsing.ts",
         "./unittests/commandLineParsing.ts",
+        "./unittests/configurationExtension.ts",
         "./unittests/convertCompilerOptionsFromJson.ts",
         "./unittests/convertTypingOptionsFromJson.ts",
         "./unittests/tsserverProjectSystem.ts",

src/harness/unittests/configurationExtension.ts

@@ -0,0 +1,187 @@
+/// <reference path="..\harness.ts" />
+/// <reference path="..\virtualFileSystem.ts" />
+
+namespace ts {
+    const testContents = {
+        "/dev/tsconfig.json": `{
+  "extends": "./configs/base",
+  "files": [
+    "main.ts",
+    "supplemental.ts"
+  ]
+}`,
+        "/dev/tsconfig.nostrictnull.json": `{
+  "extends": "./tsconfig",
+  "compilerOptions": {
+    "strictNullChecks": false
+  }
+}`,
+        "/dev/configs/base.json": `{
+  "compilerOptions": {
+    "allowJs": true,
+    "noImplicitAny": true,
+    "strictNullChecks": true
+  }
+}`,
+        "/dev/configs/tests.json": `{
+  "compilerOptions": {
+    "preserveConstEnums": true,
+    "removeComments": false,
+    "sourceMap": true
+  },
+  "exclude": [
+    "../tests/baselines",
+    "../tests/scenarios"
+  ],
+  "include": [
+    "../tests/**/*.ts"
+  ]
+}`,
+        "/dev/circular.json": `{
+    "extends": "./circular2",
+    "compilerOptions": {
+        "module": "amd"
+    }
+}`,
+        "/dev/circular2.json": `{
+    "extends": "./circular",
+    "compilerOptions": {
+        "module": "commonjs"
+    }
+}`,
+        "/dev/missing.json": `{
+    "extends": "./missing2",
+    "compilerOptions": {
+        "types": []
+    }
+}`,
+        "/dev/failure.json": `{
+    "extends": "./failure2.json",
+    "compilerOptions": {
+        "typeRoots": []
+    }
+}`,
+        "/dev/failure2.json": `{
+    "excludes": ["*.js"]
+}`,
+        "/dev/configs/first.json": `{
+    "extends": "./base",
+    "compilerOptions": {
+        "module": "commonjs"
+    },
+    "files": ["../main.ts"]
+}`,
+        "/dev/configs/second.json": `{
+    "extends": "./base",
+    "compilerOptions": {
+        "module": "amd"
+    },
+    "include": ["../supplemental.*"]
+}`,
+        "/dev/extends.json": `{ "extends": 42 }`,
+        "/dev/extends2.json": `{ "extends": "configs/base" }`,
+        "/dev/main.ts": "",
+        "/dev/supplemental.ts": "",
+        "/dev/tests/unit/spec.ts": "",
+        "/dev/tests/utils.ts": "",
+        "/dev/tests/scenarios/first.json": "",
+        "/dev/tests/baselines/first/output.ts": ""
+    };
+
+    const caseInsensitiveBasePath = "c:/dev/";
+    const caseInsensitiveHost = new Utils.MockParseConfigHost(caseInsensitiveBasePath, /*useCaseSensitiveFileNames*/ false, mapObject(testContents, (key, content) => [`c:${key}`, content]));
+
+    const caseSensitiveBasePath = "/dev/";
+    const caseSensitiveHost = new Utils.MockParseConfigHost(caseSensitiveBasePath, /*useCaseSensitiveFileNames*/ true, testContents);
+
+    function verifyDiagnostics(actual: Diagnostic[], expected: {code: number, category: DiagnosticCategory, messageText: string}[]) {
+        assert.isTrue(expected.length === actual.length, `Expected error: ${JSON.stringify(expected)}. Actual error: ${JSON.stringify(actual)}.`);
+        for (let i = 0; i < actual.length; i++) {
+            const actualError = actual[i];
+            const expectedError = expected[i];
+            assert.equal(actualError.code, expectedError.code, "Error code mismatch");
+            assert.equal(actualError.category, expectedError.category, "Category mismatch");
+            assert.equal(flattenDiagnosticMessageText(actualError.messageText, "\n"), expectedError.messageText);
+        }
+    }
+
+    describe("Configuration Extension", () => {
+        forEach<[string, string, Utils.MockParseConfigHost], void>([
+            ["under a case insensitive host", caseInsensitiveBasePath, caseInsensitiveHost],
+            ["under a case sensitive host", caseSensitiveBasePath, caseSensitiveHost]
+        ], ([testName, basePath, host]) => {
+            function testSuccess(name: string, entry: string, expected: CompilerOptions, expectedFiles: string[]) {
+                it(name, () => {
+                    const {config, error} = ts.readConfigFile(entry, name => host.readFile(name));
+                    assert(config && !error, flattenDiagnosticMessageText(error && error.messageText, "\n"));
+                    const parsed = ts.parseJsonConfigFileContent(config, host, basePath, {}, entry);
+                    assert(!parsed.errors.length, flattenDiagnosticMessageText(parsed.errors[0] && parsed.errors[0].messageText, "\n"));
+                    expected.configFilePath = entry;
+                    assert.deepEqual(parsed.options, expected);
+                    assert.deepEqual(parsed.fileNames, expectedFiles);
+                });
+            }
+
+            function testFailure(name: string, entry: string, expectedDiagnostics: {code: number, category: DiagnosticCategory, messageText: string}[]) {
+                it(name, () => {
+                    const {config, error} = ts.readConfigFile(entry, name => host.readFile(name));
+                    assert(config && !error, flattenDiagnosticMessageText(error && error.messageText, "\n"));
+                    const parsed = ts.parseJsonConfigFileContent(config, host, basePath, {}, entry);
+                    verifyDiagnostics(parsed.errors, expectedDiagnostics);
+                });
+            }
+
+            describe(testName, () => {
+                testSuccess("can resolve an extension with a base extension", "tsconfig.json", {
+                    allowJs: true,
+                    noImplicitAny: true,
+                    strictNullChecks: true,
+                }, [
+                    combinePaths(basePath, "main.ts"),
+                    combinePaths(basePath, "supplemental.ts"),
+                ]);
+
+                testSuccess("can resolve an extension with a base extension that overrides options", "tsconfig.nostrictnull.json", {
+                    allowJs: true,
+                    noImplicitAny: true,
+                    strictNullChecks: false,
+                }, [
+                    combinePaths(basePath, "main.ts"),
+                    combinePaths(basePath, "supplemental.ts"),
+                ]);
+
+                testFailure("can report errors on circular imports", "circular.json", [
+                    {
+                        code: 18000,
+                        category: DiagnosticCategory.Error,
+                        messageText: `Circularity detected while resolving configuration: ${[combinePaths(basePath, "circular.json"), combinePaths(basePath, "circular2.json"), combinePaths(basePath, "circular.json")].join(" -> ")}`
+                    }
+                ]);
+
+                testFailure("can report missing configurations", "missing.json", [{
+                    code: 6096,
+                    category: DiagnosticCategory.Message,
+                    messageText: `File './missing2' does not exist.`
+                }]);
+
+                testFailure("can report errors in extended configs", "failure.json", [{
+                    code: 6114,
+                    category: DiagnosticCategory.Error,
+                    messageText: `Unknown option 'excludes'. Did you mean 'exclude'?`
+                }]);
+
+                testFailure("can error when 'extends' is not a string", "extends.json", [{
+                    code: 5024,
+                    category: DiagnosticCategory.Error,
+                    messageText: `Compiler option 'extends' requires a value of type string.`
+                }]);
+
+                testFailure("can error when 'extends' is neither relative nor rooted.", "extends2.json", [{
+                    code: 18001,
+                    category: DiagnosticCategory.Error,
+                    messageText: `The path in an 'extends' options must be relative or rooted.`
+                }]);
+            });
+        });
+    });
+}