Allow --composite false or --composite null on the command line

src/compiler/commandLineParser.ts

@@ -434,6 +434,7 @@ namespace ts {
             type: "boolean",
             affectsEmit: true,
             isTSConfigOnly: true,
+            isTsConfigOnlyButAllowsCommandLineFalsy: true,
             category: Diagnostics.Basic_Options,
             description: Diagnostics.Enable_project_compilation,
             transpileOptionValue: undefined
@@ -1279,44 +1280,70 @@ namespace ts {
         errors: Diagnostic[]
     ) {
         if (opt.isTSConfigOnly) {
-            errors.push(createCompilerDiagnostic(Diagnostics.Option_0_can_only_be_specified_in_tsconfig_json_file, opt.name));
+            if (opt.isTsConfigOnlyButAllowsCommandLineFalsy) {
+                Debug.assert(opt.type === "boolean", "Currently tsconfig only option with only boolean types are allowed to specify falsy value on command line");
+                const optValue = args[i];
+                switch (optValue) {
+                    case "false":
+                        options[opt.name] = false;
+                        i++;
+                        break;
+                    case "undefined":
+                    case "null":
+                        options[opt.name] = undefined;
+                        i++;
+                        break;
+                    default:
+                        if (optValue === "true") i++;
+                        errors.push(createCompilerDiagnostic(Diagnostics.Option_0_can_only_be_specified_in_tsconfig_json_file_or_set_to_false_or_undefined_on_command_line, opt.name));
+                }
+            }
+            else {
+                errors.push(createCompilerDiagnostic(Diagnostics.Option_0_can_only_be_specified_in_tsconfig_json_file, opt.name));
+            }
         }
         else {
             // Check to see if no argument was provided (e.g. "--locale" is the last command-line argument).
             if (!args[i] && opt.type !== "boolean") {
                 errors.push(createCompilerDiagnostic(diagnostics.optionTypeMismatchDiagnostic, opt.name, getCompilerOptionValueTypeString(opt)));
             }
 
-            switch (opt.type) {
-                case "number":
-                    options[opt.name] = parseInt(args[i]);
-                    i++;
-                    break;
-                case "boolean":
-                    // boolean flag has optional value true, false, others
-                    const optValue = args[i];
-                    options[opt.name] = optValue !== "false";
-                    // consume next argument as boolean flag value
-                    if (optValue === "false" || optValue === "true") {
+            if (args[i] !== "undefined" && args[i] !== "null") {
+                switch (opt.type) {
+                    case "number":
+                        options[opt.name] = parseInt(args[i]);
                         i++;
-                    }
-                    break;
-                case "string":
-                    options[opt.name] = args[i] || "";
-                    i++;
-                    break;
-                case "list":
-                    const result = parseListTypeOption(opt, args[i], errors);
-                    options[opt.name] = result || [];
-                    if (result) {
+                        break;
+                    case "boolean":
+                        // boolean flag has optional value true, false, others
+                        const optValue = args[i];
+                        options[opt.name] = optValue !== "false";
+                        // consume next argument as boolean flag value
+                        if (optValue === "false" || optValue === "true") {
+                            i++;
+                        }
+                        break;
+                    case "string":
+                        options[opt.name] = args[i] || "";
                         i++;
-                    }
-                    break;
-                // If not a primitive, the possible types are specified in what is effectively a map of options.
-                default:
-                    options[opt.name] = parseCustomTypeOption(<CommandLineOptionOfCustomType>opt, args[i], errors);
-                    i++;
-                    break;
+                        break;
+                    case "list":
+                        const result = parseListTypeOption(opt, args[i], errors);
+                        options[opt.name] = result || [];
+                        if (result) {
+                            i++;
+                        }
+                        break;
+                    // If not a primitive, the possible types are specified in what is effectively a map of options.
+                    default:
+                        options[opt.name] = parseCustomTypeOption(<CommandLineOptionOfCustomType>opt, args[i], errors);
+                        i++;
+                        break;
+                }
+            }
+            else {
+                options[opt.name] = undefined;
+                i++;
             }
         }
         return i;
@@ -2170,7 +2197,7 @@ namespace ts {
     }
 
     function convertToOptionValueWithAbsolutePaths(option: CommandLineOption | undefined, value: CompilerOptionsValue, toAbsolutePath: (path: string) => string) {
-        if (option) {
+        if (option && !isNullOrUndefined(value)) {
             if (option.type === "list") {
                 const values = value as readonly (string | number)[];
                 if (option.element.isFilePath && values.length) {

src/compiler/diagnosticMessages.json

@@ -4292,6 +4292,10 @@
         "category": "Message",
         "code": 6228
     },
+    "Option '{0}' can only be specified in 'tsconfig.json' file or set to 'false' or 'undefined' on command line.": {
+        "category": "Error",
+        "code": 6229
+    },
 
     "Projects to reference": {
         "category": "Message",

src/compiler/types.ts

@@ -5314,6 +5314,7 @@ namespace ts {
         description?: DiagnosticMessage;                        // The message describing what the command line switch does
         paramType?: DiagnosticMessage;                          // The name to be used for a non-boolean option's parameter
         isTSConfigOnly?: boolean;                               // True if option can only be specified via tsconfig.json file
+        isTsConfigOnlyButAllowsCommandLineFalsy?: boolean;                      // True if option can only be specified via tsconfig.json file but on command line can set false values
         isCommandLineOnly?: boolean;
         showInSimplifiedHelpView?: boolean;
         category?: DiagnosticMessage;

src/testRunner/tsconfig.json

@@ -126,6 +126,7 @@
         "unittests/tsbuild/transitiveReferences.ts",
         "unittests/tsbuild/watchEnvironment.ts",
         "unittests/tsbuild/watchMode.ts",
+        "unittests/tsc/composite.ts",
         "unittests/tsc/declarationEmit.ts",
         "unittests/tsc/incremental.ts",
         "unittests/tsc/listFilesOnly.ts",

src/testRunner/unittests/config/commandLineParsing.ts

@@ -414,6 +414,92 @@ namespace ts {
                 });
         });
 
+        describe("parse --composite", () => {
+            it("allows setting it to false", () => {
+                assertParseResult(["--composite", "false", "0.ts"],
+                    {
+                        errors: [],
+                        fileNames: ["0.ts"],
+                        options: { composite: false }
+                    });
+            });
+
+            it("allows setting it to undefined and tsbuild info to undefined", () => {
+                assertParseResult(["--composite", "undefined", "-tsBuildInfoFile", "undefined", "0.ts"],
+                    {
+                        errors: [],
+                        fileNames: ["0.ts"],
+                        options: { composite: undefined, tsBuildInfoFile: undefined }
+                    });
+            });
+
+            it("allows setting it to null and tsbuild info to null", () => {
+                assertParseResult(["--composite", "null", "-tsBuildInfoFile", "null", "0.ts"],
+                    {
+                        errors: [],
+                        fileNames: ["0.ts"],
+                        options: { composite: undefined, tsBuildInfoFile: undefined }
+                    });
+            });
+
+            it("Errors if set to true", () => {
+                // --lib es6 0.ts
+                assertParseResult(["--composite", "true", "0.ts"],
+                    {
+                        errors: [
+                            {
+                                messageText: formatStringFromArgs(Diagnostics.Option_0_can_only_be_specified_in_tsconfig_json_file_or_set_to_false_or_undefined_on_command_line.message, ["composite"]),
+                                category: Diagnostics.Option_0_can_only_be_specified_in_tsconfig_json_file_or_set_to_false_or_undefined_on_command_line.category,
+                                code: Diagnostics.Option_0_can_only_be_specified_in_tsconfig_json_file_or_set_to_false_or_undefined_on_command_line.code,
+                                file: undefined,
+                                start: undefined,
+                                length: undefined
+                            }
+                        ],
+                        fileNames: ["0.ts"],
+                        options: {}
+                    });
+            });
+
+            it("Errors if its last parameter", () => {
+                // --lib es6 0.ts
+                assertParseResult(["0.ts", "--composite"],
+                    {
+                        errors: [
+                            {
+                                messageText: formatStringFromArgs(Diagnostics.Option_0_can_only_be_specified_in_tsconfig_json_file_or_set_to_false_or_undefined_on_command_line.message, ["composite"]),
+                                category: Diagnostics.Option_0_can_only_be_specified_in_tsconfig_json_file_or_set_to_false_or_undefined_on_command_line.category,
+                                code: Diagnostics.Option_0_can_only_be_specified_in_tsconfig_json_file_or_set_to_false_or_undefined_on_command_line.code,
+                                file: undefined,
+                                start: undefined,
+                                length: undefined
+                            }
+                        ],
+                        fileNames: ["0.ts"],
+                        options: {}
+                    });
+            });
+
+            it("Errors if its followed by other option", () => {
+                // --lib es6 0.ts
+                assertParseResult(["0.ts", "--composite", "--strictNullChecks"],
+                    {
+                        errors: [
+                            {
+                                messageText: formatStringFromArgs(Diagnostics.Option_0_can_only_be_specified_in_tsconfig_json_file_or_set_to_false_or_undefined_on_command_line.message, ["composite"]),
+                                category: Diagnostics.Option_0_can_only_be_specified_in_tsconfig_json_file_or_set_to_false_or_undefined_on_command_line.category,
+                                code: Diagnostics.Option_0_can_only_be_specified_in_tsconfig_json_file_or_set_to_false_or_undefined_on_command_line.code,
+                                file: undefined,
+                                start: undefined,
+                                length: undefined
+                            }
+                        ],
+                        fileNames: ["0.ts"],
+                        options: { strictNullChecks: true }
+                    });
+            });
+        });
+
         describe("Watch options", () => {
             it("parse --watchFile", () => {
                 assertParseResult(["--watchFile", "UseFsEvents", "0.ts"],

src/testRunner/unittests/tsc/composite.ts

@@ -0,0 +1,101 @@
+namespace ts {
+    describe("unittests:: tsc:: composite::", () => {
+        verifyTsc({
+            scenario: "composite",
+            subScenario: "when setting composite false on command line",
+            fs: () => loadProjectFromFiles({
+                "/src/project/src/main.ts": "export const x = 10;",
+                "/src/project/tsconfig.json": Utils.dedent`
+                    {
+                        "compilerOptions": {
+                            "target": "es5",
+                            "module": "commonjs",
+                        },
+                        "include": [
+                            "src/**/*.ts"
+                        ]
+                    }`,
+            }),
+            commandLineArgs: ["--composite", "false", "--p", "src/project"],
+        });
+
+        verifyTsc({
+            scenario: "composite",
+            subScenario: "when setting composite undefined on command line",
+            fs: () => loadProjectFromFiles({
+                "/src/project/src/main.ts": "export const x = 10;",
+                "/src/project/tsconfig.json": Utils.dedent`
+                    {
+                        "compilerOptions": {
+                            "target": "es5",
+                            "module": "commonjs",
+                        },
+                        "include": [
+                            "src/**/*.ts"
+                        ]
+                    }`,
+            }),
+            commandLineArgs: ["--composite", "undefined", "--p", "src/project"],
+        });
+
+        verifyTsc({
+            scenario: "composite",
+            subScenario: "when setting composite false on command line but has tsbuild info in config",
+            fs: () => loadProjectFromFiles({
+                "/src/project/src/main.ts": "export const x = 10;",
+                "/src/project/tsconfig.json": Utils.dedent`
+                    {
+                        "compilerOptions": {
+                            "target": "es5",
+                            "module": "commonjs",
+                            "tsBuildInfoFile": "tsconfig.json.tsbuildinfo"
+                        },
+                        "include": [
+                            "src/**/*.ts"
+                        ]
+                    }`,
+            }),
+            commandLineArgs: ["--composite", "false", "--p", "src/project"],
+        });
+
+        verifyTsc({
+            scenario: "composite",
+            subScenario: "when setting composite false and tsbuildinfo as undefined on command line but has tsbuild info in config",
+            fs: () => loadProjectFromFiles({
+                "/src/project/src/main.ts": "export const x = 10;",
+                "/src/project/tsconfig.json": Utils.dedent`
+                    {
+                        "compilerOptions": {
+                            "target": "es5",
+                            "module": "commonjs",
+                            "tsBuildInfoFile": "tsconfig.json.tsbuildinfo"
+                        },
+                        "include": [
+                            "src/**/*.ts"
+                        ]
+                    }`,
+            }),
+            commandLineArgs: ["--composite", "false", "--p", "src/project", "--tsBuildInfoFile", "undefined"],
+        });
+
+        verifyTsc({
+            scenario: "composite",
+            subScenario: "when setting composite false and tsbuildinfo as null on command line but has tsbuild info in config",
+            fs: () => loadProjectFromFiles({
+                "/src/project/src/main.ts": "export const x = 10;",
+                "/src/project/tsconfig.json": Utils.dedent`
+                    {
+                        "compilerOptions": {
+                            "target": "es5",
+                            "module": "commonjs",
+                            "tsBuildInfoFile": "tsconfig.json.tsbuildinfo"
+                        },
+                        "include": [
+                            "src/**/*.ts"
+                        ]
+                    }`,
+            }),
+            commandLineArgs: ["--composite", "false", "--p", "src/project", "--tsBuildInfoFile", "null"],
+        });
+    });
+}

tests/baselines/reference/tsc/composite/initial-build/when-setting-composite-false-and-tsbuildinfo-as-null-on-command-line-but-has-tsbuild-info-in-config.js

@@ -0,0 +1,11 @@
+//// [/lib/initial-buildOutput.txt]
+/lib/tsc --composite false --p src/project --tsBuildInfoFile null
+exitCode:: ExitStatus.Success
+
+
+//// [/src/project/src/main.js]
+"use strict";
+Object.defineProperty(exports, "__esModule", { value: true });
+exports.x = 10;
+
+

tests/baselines/reference/tsc/composite/initial-build/when-setting-composite-false-and-tsbuildinfo-as-undefined-on-command-line-but-has-tsbuild-info-in-config.js

@@ -0,0 +1,11 @@
+//// [/lib/initial-buildOutput.txt]
+/lib/tsc --composite false --p src/project --tsBuildInfoFile undefined
+exitCode:: ExitStatus.Success
+
+
+//// [/src/project/src/main.js]
+"use strict";
+Object.defineProperty(exports, "__esModule", { value: true });
+exports.x = 10;
+
+

tests/baselines/reference/tsc/composite/initial-build/when-setting-composite-false-on-command-line-but-has-tsbuild-info-in-config.js

@@ -0,0 +1,12 @@
+//// [/lib/initial-buildOutput.txt]
+/lib/tsc --composite false --p src/project
+src/project/tsconfig.json(5,9): error TS5069: Option 'tsBuildInfoFile' cannot be specified without specifying option 'incremental' or option 'composite'.
+exitCode:: ExitStatus.DiagnosticsPresent_OutputsGenerated
+
+
+//// [/src/project/src/main.js]
+"use strict";
+Object.defineProperty(exports, "__esModule", { value: true });
+exports.x = 10;
+
+

tests/baselines/reference/tsc/composite/initial-build/when-setting-composite-false-on-command-line.js

@@ -0,0 +1,11 @@
+//// [/lib/initial-buildOutput.txt]
+/lib/tsc --composite false --p src/project
+exitCode:: ExitStatus.Success
+
+
+//// [/src/project/src/main.js]
+"use strict";
+Object.defineProperty(exports, "__esModule", { value: true });
+exports.x = 10;
+
+

tests/baselines/reference/tsc/composite/initial-build/when-setting-composite-undefined-on-command-line.js

@@ -0,0 +1,11 @@
+//// [/lib/initial-buildOutput.txt]
+/lib/tsc --composite undefined --p src/project
+exitCode:: ExitStatus.Success
+
+
+//// [/src/project/src/main.js]
+"use strict";
+Object.defineProperty(exports, "__esModule", { value: true });
+exports.x = 10;
+
+