grunt-ts

TypeScript Compilation Task for GruntJS

Grunt-ts is an npm package that handles TypeScript compilation work in GruntJS build scripts. This project, much like Grunt itself, is now in a mature maintenance phase and no significant features will be considered. New maintainers welcome!

Grunt-ts provides a Grunt-compatible wrapper for the tsc command-line compiler, and provides some additional functionality that improves the TypeScript development workflow. Grunt-ts supports compiling against tsconfig.json or even a Visual Studio project directly. Grunt-ts is itself written in TypeScript.

Looking for Maintainers

Do you use grunt-ts? Would you like to help keep it up-to-date for new TypeScript versions? Please let @nycdotnet know.

How To Contribute

Thank you for your interest in contributing! Please see the contributing guide for details.

Latest Changes

Latest recommended release is 6.0.0-beta.22, which has native support for features added in TypeScript 2.7, and is compatible with any future version of TypeScript by using the tsconfig.json passthrough feature, or the additionalFlags option. Latest "stable" (though very old at this point) release is 5.5.1 with built-in support for features up to TypeScript 1.8. Full changelog is here.

Quickstart

To install grunt-ts, you must first install TypeScript and GruntJS.

• If you don't have TypeScript installed in your project, run npm install typescript --save-dev.
• If you don't have GruntJS installed in your project, run npm install grunt --save-dev.
• If you have never used Grunt on your system, install the grunt-cli globally: npm install grunt-cli -g.

Breaking Changes with Grunt-ts 6

• The npm tool has effectively deprecated peer dependencies, so Grunt and TypeScript will no longer automatically be installed when installing grunt-ts. This means you'll just have to install them manually and add them as devDependencies in your package.json.
• Grunt 1.0 is more strict with templates so it is not possible to use <% and %> as tokens for html replacements with grunt-ts anymore. In grunt-ts 6.0 and higher, you must use {% and %} for HTML replacement tokens.
• The blue text with each file name will no longer be displayed in fast mode unless verbose: true is specified in the task or target options (See #389).

Getting Started

If you've never used GruntJS on your computer, you should follow the detailed instructions here to get Node.js and the grunt-cli working. If you're a Grunt expert, follow these steps:

• Run npm install grunt-ts in your project directory; this will install grunt-ts, TypeScript, and GruntJS.
• Add the ts task in your Gruntfile.js (see below for a minimalist one).
• Run grunt at the command line in your project folder to compile your TypeScript code.

This minimalist Gruntfile.js will compile your TypeScript project using the specified tsconfig.json file. Using a tsconfig.json is the best way to use TypeScript:

// 
module.exports = function(grunt) {
  grunt.initConfig({
    ts: {
      default : {
        tsconfig: './tsconfig.json'
      }
    }
  });
  grunt.loadNpmTasks("grunt-ts");
  grunt.registerTask("default", ["ts"]);
};

If you prefer the GruntJS idiom, this minimalist Gruntfile.js will compile *.ts files in all subdirectories of the project folder, excluding anything under node_modules. Please note - it is almost always better to use a tsconfig.json to compile your TypeScript instead of doing it this way:

module.exports = function(grunt) {
  grunt.initConfig({
    ts: {
      default : {
        src: ["**/*.ts", "!node_modules/**"]
      }
    }
  });
  grunt.loadNpmTasks("grunt-ts");
  grunt.registerTask("default", ["ts"]);
};

A more extensive sample Gruntfile.js is available here.

Grunt-ts Features

• Allows use of all standard GruntJS functionality such as use of customizable task targets, globbing, use of the files object (for instantiating multiple independent tsc runs in a single target), etc.
• Allows the developer to select a custom TypeScript compiler version for their project, or even use a custom (in-house) version.
• Supports most switches of the tsc TypeScript Compiler via options in the gruntfile ts task, and also supports switch overrides per-target.
• Supports Visual Studio Projects as a compile target for identifying TypeScript files, setting up compile configuration, or both.
• Supports TypeScript Projects via tsconfig.json when used with TypeScript 1.5 or higher.
• Provides a transforms feature that eases code refactoring by taking the burden of relative path maintenance off the developer. If the paths to a set of files changes, grunt-ts will regenerate the relevant sections. This feature supports:
  • External module import transforms by file name, aliasing, directories, indexed directories, and re-exported imports.
  • Internal module reference maintenance
  • Common reference file management
• Allows concatenation where supported by the TypeScript compiler's --out switch
• Encodes HTML files as TypeScript variables (for HTML templating engines)
• Performs live file watching (compile on save)
• Enables "Fast" compile when using external modules

Support for tsc Switches

Grunt-ts provides explicit support for most tsc switches. Any arbitrary switches can be passed to tsc via the additionalFlags feature.

|tsc switch|name in grunt-ts|description| |:----:|:----:|:-----| |--allowJs|allowJs|Allow JavaScript files (.js) to be compiled.| |--allowSyntheticDefaultImports|allowSyntheticDefaultImports|Allows use "default" ES6 module import syntax with pre-ES6 libraries that don't have a default (on by default with SystemJS)| |--allowUnreachableCode|allowUnreachableCode|Do not report errors on unreachable code.| |--allowUnusedLabels|allowUnusedLabels|Do not report errors on unused labels.| |--declaration|declaration|Generates a .d.ts definitions file for compiled TypeScript files| |--emitDecoratorMetadata|emitDecoratorMetadata|Emit metadata for type/parameter decorators.| |--esModuleInterop|esModuleInterop|Requires default import of callable CommonJS modules but with runtime behavior like Babel or Webpack.| |--experimentalAsyncFunctions|experimentalAsyncFunctions|Enables experimental support for proposed ECMAScript async functions| |--experimentalDecorators|experimentalDecorators|Enables experimental support for proposed ECMAScript decorators| |--forceConsistentCasingInFileNames|forceConsistentCasingInFileNames|Disallow inconsistently-cased references to the same file.| |--inlineSourceMap|inlineSourceMap|Emit a single file that includes source maps instead of emitting a separate .js.map file.| |--inlineSources|inlineSources|Emit the TypeScript source alongside the sourcemaps within a single file; requires --inlineSourceMap to be set.| |--isolatedModules|isolatedModules|Ensures that the output is safe to only emit single files by making cases that break single-file transpilation an error| |--jsx|jsx|Specifies the JSX code generation style: 'preserve' or 'react'| |--lib|lib|List of library files to be included in the compilation.| |--locale|locale|Specify locale for error messages.| |--mapRoot LOCATION|mapRoot|Specifies the location where debugger should locate map files instead of generated locations.| |--module KIND|module|Specify module style for code generation| |--moduleResolution KIND|moduleResolution|Specifies module resolution strategy: 'node' (Node.js) or 'classic' (TypeScript pre-1.6).| |--newLine|newLine|Explicitly specify newline character (CRLF or LF); if omitted, uses OS default.| |--noEmit|noEmit|Check, but do not emit JS, even in the absence of errors.| |--noEmitHelpers|noEmitHelpers|Do not generate custom helper functions like __extends in compiled output.| |--noEmitOnError|noEmitOnError|Do not emit JavaScript if there is a compilation error| |--noFallthroughCasesInSwitch|noFallthroughCasesInSwitch|Report errors for fallthrough cases in switch statement.| |--noImplicitAny|noImplicitAny|Warn on expressions and declarations with an implied any type.| |--noImplicitUseStrict|noImplicitUseStrict|Warn on expressions and declarations with an implied any type.| |--noImplicitReturns|noImplicitReturns|Report error when not all code paths in function return a value.| |--noImplicitThis|noImplicitThis|Raise error on this expressions with an implied any type.| |--noStrictGenericChecks|noStrictGenericChecks|Disable strict checking of generic signatures in function types.| |--noLib|noLib|Do not automatically include lib.d.ts is compilation context.| |--noResolve|noResolve|Do not add triple-slash references or module import targets to the compilation context.| |--out FILE|out|Concatenate and emit output to a single file.| |--outDir DIRECTORY|outDir|Redirect output structure to the directory.| |--preserveConstEnums|preserveConstEnums|Const enums will be kept as enums in the emitted JS.| |--preserveSymlinks|preserveSymlinks|Do not resolve symlinks to their real path; treat a symlinked file like a real one.| |--pretty|pretty|Stylize errors and messages using color and context.| |--reactNamespace|reactNamespace|Specifies the object invoked for createElement and __spread when targeting 'react' JSX emit.| |--removeComments|removeComments|Configures if comments should be included in the output| |--rootDir|rootDir|Allows override of common root folder calculated by --outDir.| |--skipDefaultLibCheck|skipDefaultLibCheck|Don't check a user-defined default lib file's validity.| |--skipLibCheck|skipLibCheck|Skip type checking of all declaration files (.d.ts).| |--sourceMap|sourceMap|Generates corresponding .map file| |--sourceRoot LOCATION|sourceRoot|Specifies the location where debugger should locate TypeScript files instead of source locations.| |--strict|strict|Macro for all strict behavior| |--strictFunctionTypes|strictFunctionTypes|Enforce contravariant function parameter comparison| |--strictNullChecks|strictNullChecks|Enables strict null checking mode.| |--strictPropertyInitialization|strictPropertyInitialization|Ensure properties are initialized before use| |--stripInternal|stripInternal|does not emit members marked as @internal.| |--suppressExcessPropertyErrors|suppressExcessPropertyErrors|Disables strict object literal assignment checking (experimental).| |--suppressImplicitAnyIndexErrors|suppressImplicitAnyIndexErrors|Specifies the location where debugger should locate TypeScript files instead of source locations.| |--target VERSION|target|Specify ECMAScript target version: 'es3', 'es5', or 'es6'|

For file ordering, look at JavaScript Generation.

grunt-ts gruntfile.js options

|grunt-ts property|where to define|description| |:----|:----|:-----| |additionalFlags|option|string - allows passing arbitrary strings to the compiler. This is intended to enable compatibility with features not supported directly by grunt-ts.| |allowJs|option|true, false (default) - Allow JavaScript files (.js) to be compiled.| |allowUnreachableCode|option|true, false (default) - Do not report errors on unreachable code.| |allowUnusedLabels|option|true, false (default) - Do not report errors on unused labels.| |allowSyntheticDefaultImports|option|true, false (default) - Allows use "default" ES6 module import syntax with pre-ES6 libraries that don't have a default (on by default with SystemJS and not required to specify).| |baseDir|option|string - Deprecated - use rootDir with TypeScript 1.5 or newer. Sets root directory for maintaining source structure when using outDir and fast together.| |comments|option|true, false (default) - include comments in emitted JS.| |compile|option|true (default), false - compile TypeScript code.| |compiler|option|string - path to custom compiler| |declaration|option|true, false (default) - indicates that definition files should be emitted.| |emitDecoratorMetadata|option|true, false (default) - set to true to emit metadata for proposed ECMAScript decorators (will enable experimentalDecorators)| |emitGruntEvents|option|true, false (default) - set to true to raise an event in Grunt upon failed builds.| |esModuleInterop|option|true, false (default) - set to true to enable the interop behavior.| |experimentalAsyncFunctions|option|true, false (default) - set to true to enable support for proposed ECMAScript async functions (in ES6 mode only)| |experimentalDecorators|option|true, false (default) - set to true to enable support for proposed ECMAScript decorators| |failOnTypeErrors|option|true (default), false - fail Grunt pipeline if there is a type error. (See also noEmitOnError)| |fast|option|'watch' (default), 'always', 'never' - how to decide on a "fast" grunt-ts compile.| |forceCompileRegex|option|Prevents files matching the given regex from being cached.| |files|target|Sets of files to compile and optional output destination| |forceCompileRegex|option|string representing a RegEx - If specified, files that match the RegEx will be included in the compilation context with fast even if they would have otherwise been excluded.| |forceConsistentCasingInFileNames|option|true, false (default) - Disallow inconsistently-cased references to the same file.| |html|target|string or string[] - glob to HTML templates| |htmlModuleTemplate|option|string - HTML template namespace| |htmlOutDir|option|string - Sets a root for output of transformed-to-TypeScript HTML files| |htmlOutDirFlatten|option|true, false (default) - Will flatten the transformed HTML files to a single folder| |htmlVarTemplate|option|string - HTML property name| |inlineSourceMap|option|true, false (default) Emit a single file that includes source maps instead of emitting a separate .js.map file; If enabled, will automatically enable sourceMap.| |inlineSources|option|true, false (default) Emit the TypeScript source alongside the sourcemaps within a single file; If enabled, will automatically enable inlineSourceMap and sourceMap.| |isolatedModules|option|true, false (default) Ensures that the output is safe to only emit single files by making cases that break single-file transpilation an error.| |jsx|option|'preserve', 'react', (TypeScript default is 'react'). If 'preserve', TypeScript will emit .jsx; if 'react', TypeScript will transpile and emit .js files.| |lib|option|string[]. List of library files to be included in the compilation. If --lib is not specified a default library is injected.| |locale|option|string - specify locale for error messages| |mapRoot|option|string - root for referencing .js.map files in JS| |module|option|default is none (''), but can be set to 'amd', 'commonjs', 'system', or other values.| |moduleResolution|option|'classic' or 'node'. This was introduced in TypeScript 1.6. The default is 'node' if not passed. More details here.| |newLine|option|CRLF, LF, `` (default) - If passed with a value, TypeScript will use the specified line endings. Also affects grunt-ts transforms.| |noEmit|option|true, false (default) - If passed as true, TypeScript will not emit even if it compiles cleanly| |noEmitHelpers|option|true, false (default) - If passed as true, TypeScript will not generate custom helper functions like __extends in compiled output| |noEmitOnError|option|true, false (default) - If passed as true, TypeScript will not emit JS if there is an error (see also failOnTypeErrors)| |noFallthroughCasesInSwitch|option|true, false (default) - Report errors for fallthrough cases in switch statement.| |noImplicitAny|option|true, false (default) - enable for stricter type checking| |noImplicitReturns|option|true, false (default) - Report error when not all code paths in function return a value.| |noImplicitThis|option|true, false (default) - Raise error on this expressions with an implied any type.| |noLib|option|true, false (default) - do not automatically include lib.d.ts in compilation context| |noResolve|option|true, false (default) - for deprecated version of TypeScript| |noStrictGenericChecks|option|true, false (default) - Disable strict checking of generic signatures in function types.| |options|target|| |out|target|string - instruct tsc to concatenate output to this file.| |outDir|target|string - instruct tsc to emit JS to this directory.| |preserveConstEnums|option|true, false (default) - If true, const enums will be kept as enums in the emitted JS.| |preserveSymlinks|option|true, false (default) - If true, do not resolve symlinks to their real path; treat a symlinked file like a real one.| |pretty|option|true, false (default) - Stylize errors and messages using color and context.| |reactNamespace|option|string - Specifies the object invoked for createElement and __spread when targeting 'react' JSX emit.| |reference|target|string - tells grunt-ts which file to use for maintaining references| |removeComments|option|true (default), false - removes comments in emitted JS| |rootDir|option|string - Allows override of common root folder calculated by --outDir.| |skipDefaultLibCheck|option|true, false (default) - Don't check a user-defined default lib file's validity.| |skipLibCheck|option|true, false (default) - Skip type checking of all declaration files (.d.ts).| |sourceRoot|option|string - root for referencing TS files in .js.map| |sourceMap|option|true (default), false - indicates if source maps should be generated (.js.map)| |strict|option|true, false (default) - Macro for all strict behavior.| |strictFunctionTypes|option|true, false (default) - Enforce contravariant function parameter comparison.| |strictNullChecks|option|true, false (default) - Enables strict null checking mode.| |strictPropertyInitialization|option|true, false (default) - Enables strict null checking mode.| |stripInternal|option|true, false (default) - does not emit members marked as @internal.| |suppressExcessPropertyErrors|option|false (default), true - indicates if TypeScript should disable strict object literal assignment checking (experimental)| |suppressImplicitAnyIndexErrors|option|false (default), true - indicates if TypeScript should allow access to properties of an object by string indexer when --noImplicitAny is active, even if TypeScript doesn't know about them.| |src|target|string or string[] - glob of TypeScript files to compile.| |target|option|'es5' (default), 'es3', or 'es6' - targeted ECMAScript version| |tsCacheDir|target|./.tscache (default), a string path where the local TS cache directory will be created when the 'fast' option is not set to 'never'.| |tsconfig|target|true, a string path, or an object. See tsconfig for details.| |verbose|option|true, false (default) - logs tsc command-line options to console| |vs|target|string referencing a .csproj or .vbproj file or, {} (object) (see Visual Studio Projects for details)| |watch|target|string - will watch for changes in the specified directory or below| |something else||Don't see the switch you're looking for? Check out additionalFlags|

Note: In the above chart, if "where to define" is "target", the property must be defined on a target or on the ts object directly. If "where to define" is "options", then the property must be defined on an options object on ts or on a target under ts.

grunt-ts target properties

dest

Grunt-ts does not support the GruntJS standard dest target property. Instead, you should use files, out, or outDir.

files

Grunt-ts supports use of the GruntJS-centric files property on a target as an alternative to the tsc-centric use of src and out/outDir.

Notes:

• The fast grunt-ts option is not supported in this configuration. You should specify fast: 'never' to avoid warnings when files is used.
• It is not supported to specify an array of values for dest with grunt-ts. A warning will be issued to the console. If a non-empty array is passed, the first element will be used and the rest will be truncated.
• If the dest parameter ends with ".js", the value will be passed to the --out parameter of the TypeScript compiler. Otherwise, if there is a non-blank value, it will be passed to the --outDir parameter.
• If you intend to pass the specific value "src" to the TypeScript --outDir parameter, specify it as "src/" in the dest parameter to avoid grunt-ts warnings.

Here are some examples of using the target files property with grunt-ts:

grunt.initConfig({
  ts: {
    compileTwoSetsOfFilesUsingArrayStyle: {
      // This will run tsc twice.  The first time, the result of the 'files1/**/*.ts' glob will be
      // passed to tsc with the --out switch as 'out/ArrayStyle/1.js'.
      // see https://github.com/gruntjs/grunt-docs/blob/master/Configuring-tasks.md#files-array-format
      files: [{ src: ['files1/**/*.ts'], dest: 'out/ArrayStyle/1.js' },
              { src: ['files2/**/*.ts'], dest: 'out/ArrayStyle/2.js' }],
      options: {
        fast: 'never'
      }
    },
    compileTwoSetsOfFilesToDirUsingArrayStyle: {
      // This will run tsc twice.  The first time, the result of the 'files1/**/*.ts' glob will be
      // passed to tsc with the --outDir switch as 'out/ArrayStyle'.
      // see https://github.com/gruntjs/grunt-docs/blob/master/Configuring-tasks.md#files-array-format
      files: [{ src: ['files1/**/*.ts'], dest: 'out/ArrayStyle' },
              { src: ['files2/**/*.ts'], dest: 'out/ArrayStyle' }],
      options: {
        fast: 'never'
      }
    },
    compileTwoSetsOfFilesUsingObjectStyle: {
      // This will run tsc twice.  The first time, the result of the 'files1/**/*.ts' glob will be
      // passed to tsc with the --out switch as 'out/ObjectStyle/1.js'.
      // see https://github.com/gruntjs/grunt-docs/blob/master/Configuring-tasks.md#files-object-format
      files: {
        'out/ObjectStyle/1.js': ['files1/**/*.ts'],
        'out/ObjectStyle/2.js': ['files2/**/*.ts']
      },
      options: {
        fast: 'never'
      }
    },
    compileTwoSetsOfFilesToDirUsingObjectStyle: {
      // This will run tsc once.  The result of the globs will be passed to tsc with the
      // --outDir switch as 'out/ObjectStyle'.
      // see https://github.com/gruntjs/grunt-docs/blob/master/Configuring-tasks.md#files-object-format
      files: {
        'out/ObjectStyle': ['files1/**/*.ts','files2/**/*.ts']
        },
        options: {
          fast: 'never'
        }
      }
    }
});

html

Grunt-ts supports compilation of .html file content to TypeScript variables which is explained in detail here. The html target property acts similarly to src, except that it searches for html files to convert to TypeScript variables. See also htmlModuleTemplate and htmlVarTemplate.

// How to use the html target property (incomplete example)
grunt.initConfig({
  ts: {
    default: {
      html: ["templates/**/*.html"]
    }
  }
});

Note: the html compilation functionality will not fire if the src property is not specified. If you wish to only have the HTML compile to TypeScript without compiling the resulting .ts files to JavaScript, make sure they're excluded from the src globs, or else specify an empty src array alongside the html task property, and set the target compile option to false:

// Example of how to compile html files to TypeScript without compiling the resulting
// .ts files to JavaScript.
grunt.initConfig({
  ts: {
    default: {
      html: ["templates/**/*.html"],
      src: [],
      options: {
        compile: false
      }
    }
  }
});

options

This section allows global configuration for the grunt-ts task. All target-specific options are supported. If a target also has options set, the target's options override the global task options.

out

Passes the --out switch to tsc. This will cause the emitted JavaScript to be concatenated to a single file if your code allows for that.

Note - the sequence of concatenation when using namespaces (formerly called internal modules) is usually significant. You can assist TypeScript to order the emitted JavaScript correctly by changing the sequence in which files appear in your glob. For example, if you have a.ts, b.ts, and c.ts and use the glob '*.ts, the default would be for TypeScript to concatenate the files in alphabetical order. If you needed the content from b.ts to appear first, and then the rest in alphabetical order, you could specify the glob like this: ['b.ts','*.ts'].

Note - the out feature should not be used in combination with module because the TypeScript compiler does not support concatenation of external modules; consider using a module bundler like WebPack, Browserify, or Require's r.js to concatenate external modules.

grunt.initConfig({
  ts: {
    default: {
      out: "dist/myscript.js"
    }
  }
});

Warning: Using the compiler with out and reference will prevent grunt-ts from using its fast compile feature. Consider using external modules with transforms instead.

outDir

Passes the --outDir switch to tsc. This will redirect the emitted JavaScript to the specified directory and subdirectories.

grunt.initConfig({
  ts: {
    default: {
      outDir: "dist"
    }
  }
});

reference

Grunt-ts can automatically generate a TypeScript file containing a reference to all other found .ts files. This means that the developer will not need to cross-reference each of their TypeScript files manually; instead, they can just reference the single reference file in each of their code files.

grunt.initConfig({
  ts: {
    default: {
      src: ["references.ts","some/other/path/**/*.ts"],
      reference: "references.ts"
    }
  }
});

Note: the TypeScript file identified in the reference property must be included in the src or files property in the Grunt target, or reference won't work (either directly or via wildcard/glob).

Note: It is not supported to use reference with files.

Warning: Using the compiler with out and reference will prevent grunt-ts from using its fast compile feature. Consider using external modules with transforms instead.

src

Allows you to specify the TypeScript files that will be passed to the compiler. Supports standard GruntJS functionality such as globbing. More info at Configuring GruntJS Tasks](http://gruntjs.com/configuring-tasks#files).

grunt.initConfig({
  ts: {
    default: {
      src: ["app/**/*.ts"]
    }
  }
});

vs

Grunt-ts can use the TypeScript compilation settings from a Visual Studio project file (.csproj or .vbproj).

In the simplest use case, specify a string identifying the Visual Studio project file name in the vs target property. Grunt-ts will extract the TypeScript settings last saved into the project file and compile the TypeScript files identified in the project in the manner specified by the Visual Studio project's configuration.

grunt.initConfig({
  ts: {
    default: {
      vs: 'test/vsproj/testproject.csproj'
    }
  }
});

If more control is desired, you may pass the vs target property as an object literal with the following properties:

• project: (string, mandatory) the relative path (from the gruntfile.js) to the Visual Studio project file.
• config: (string, optional, default = '') the Visual Studio project configuration to use (allows choosing a different project configuration than the one currently in-use/saved in Visual Studio).
• ignoreFiles: (boolean, optional, default = false) Will ignore the files identified in the Visual Studio project. This is useful if you want to keep your command-line build settings synchronized with the project's TypeScript Build settings, but want to specify a custom set of files to compile in your own src glob. If not specified or set to false, the TypeScript files referenced in the Visual Studio project will be compiled in addition to any files identified in the src target property.
• ignoreSettings: (boolean, optional, default = false) Will ignore the compile settings identified in the Visual Studio project. If specified, grunt-ts will follow its normal behavior and use any TypeScript build settings specified on the target or its defaults.

All features of grunt-ts other than files, are compatible with the vs target property. If you wish to add more files to the compilation than are referenced in the Visual Studio project, the src grunt-ts property can be used; any files found in the glob are added to the compilation list (grunt-ts will resolve duplicates). All other target properties and target options specified in the gruntfile.js will override the settings in the Visual Studio project file. For example, if you were referencing a Visual Studio project configuration that had source maps enabled, specifying sourcemap: false in the gruntfile.js would keep all other Visual Studio build settings, but disable generation of source maps.

Note: Using the vs target property with files is not supported.

Example: Use all compilation settings specified in the "Release" TypeScript configuration from the project, but compile only the TypeScript files in the lib subfolder to a single file in the built folder.

grunt.initConfig({
  ts: {
    CompileMyLibsOnly: {
      src: 'MyProject/lib/**/*.ts',
      out: 'built/mylibs.js',
      vs: {
        project: 'MyProject/MyProject.csproj',
        ignoreFiles: true,
        config: 'Release'
      }
    }
  }
});

If you wish to disable the Visual Studio built-in TypeScript build, but keep the Visual Studio project properties TypeScript Build pane working, follow these instructions.

watch

Grunt-ts can watch a directory and recompile TypeScript files when any TypeScript or HTML file is changed, added, or removed. Use the watch target option specifying a target directory that will be watched. All subdirectories are automatically included.

Note: this feature does not allow for additional tasks to run after the compilation step is done - for that you should use grunt-contrib-watch.

grunt.initConfig({
  ts: {
    default: {
      watch: "."  //will re-run this task if any .ts or .html file is changed.
    }
  }
});

grunt-ts target options

additionalFlags

Allows passing arbitrary strings to the compiler. This is intended to enable compatibility with features not supported directly by grunt-ts. The parameters will be passed exactly as-is with a space separating them from the previous switches. It is possible to pass more than one switch with additionalFlags by separating them with spaces.

grunt.initConfig({
  ts: {
    default: {
      options: {
        additionalFlags: '--autoFixBugs --gruntTs "is awesome!"'
      }
    }
  }
});

allowJs

Allows JavaScript files to be compiled. This setting works well with outDir. This feature requires grunt-ts 5.5 or higher and TypeScript 1.8 or higher.

grunt.initConfig({
  ts: {
    default: {
      src: ["**/*.ts", "**/*.js", "!emit/**", "!node_modules/**"],
      outDir: 'emit/',
      options: {
        allowJs: true
      }
    }
  }
});

allowSyntheticDefaultImports

Allows use of ES6 "default" import syntax with pre-ES6 modules when not using SystemJS. If using module format "amd", "commonjs" or "umd", the following import syntax for jQuery will give the error "Module 'jquery' has no default export" when exporting to "amd", "commonjs", or "umd" format: import * as $ from 'jquery';. In that case, passing allowSyntheticDefaultImports will eliminate this error. NOTE: This is the default behavior when SystemJS module format is used (module: "system"). This switch (and behavior) requires TypeScript 1.8 or higher. See this issue for more details.

grunt.initConfig({
  ts: {
    default: {
      options: {
        allowSyntheticDefaultImports: true,
        module: 'umd'
      }
    }
  }
});

allowUnreachableCode

When set to true, TypeScript will not report errors on unreachable code. Requires TypeScript 1.8 or higher.

grunt.initConfig({
  ts: {
    default: {
      src: ["**/*.ts", "!node_modules/**"],
      options: {
        allowUnreachableCode: true
      }
    }
  }
});

allowUnusedLabels

When set to true, TypeScript will not report errors when there are unused labels in your code. Requires TypeScript 1.8 or higher.

grunt.initConfig({
  ts: {
    default: {
      src: ["**/*.ts", "!node_modules/**"],
      options: {
        allowUnusedLabels: true
      }
    }
  }
});

baseDir

Deprecated - when using TypeScript >= 1.5 (most common), use rootDir instead.

When using fast compile with outDir, tsc won't guarantee the output directory structure will match the source structure. Setting baseDir helps to ensure the original source structure is mapped to the output directory. This will create a .baseDir.ts file in the baseDir location. A .baseDir.js and .baseDir.js.map will be created in the outDir.

grunt.initConfig({
  ts: {
    default: {
      outDir: 'dist',
      options: {
        baseDir: 'src',
        fast: always
      }
    }
  }
});

compile

true (default)| false

Indicates if the TypeScript compilation should be attempted. Turn this off if you wish to just run transforms.

grunt.initConfig({
  ts: {
    default: {
      options: {
        compile: false
      }
    }
  }
});

compiler

This target option allows the developer to select an alternate TypeScript compiler.

By default, grunt-ts will use the TypeScript compiler that came bundled with it. Alternate compilers can be used by this target option (for custom compiler builds) or using package.json (for npm released version of typescript).

To use a custom compiler, update your gruntfile.js file with this code:

grunt.initConfig({
  ts: {
    options: {
      compiler: './node_modules/grunt-ts/customcompiler/tsc'
    }
  }
});

Download custom compilers from the current TypeScript repository on GitHub or the old TypeScript repository on CodePlex and extract it to a folder in your project. The compiler will be in the bin folder. Copy all of the files to your project folder and then reference tsc using the compiler task option. For example, if you extracted everything to a mycompiler folder in your project, you'd set the grunt-ts compiler property to './mycompiler/tsc'.

In the absence of a compiler argument, grunt-ts will look for an alternate compiler in its peer node_modules folder (where grunt-ts and typescript are peers).

The package.json would look something like this for a legacy project:

{
  "devDependencies": {
    "grunt" : "~0.4.1",
    "grunt-ts" : "~1.9.2",
    "typescript" : "0.9.7"
  }
}

Note: It is safest to pin the exact TypeScript version (do not use ~ or >).

comments

true | false (default)

Retains comments in the emitted JavaScript if set to true. Removes comments if set to false. Note that if comments and removeComments are both used, the value of removeComments will win; regardless, please don't do this as it is just confusing to everyone.

grunt.initConfig({
  ts: {
    options: {
      comments: true //preserves comments in output.
    }
  }
});

declaration

true | false (default)

Generates corresponding .d.ts file(s) for compiled TypeScript files.

grunt.initConfig({
  ts: {
    options: {
      declaration: true
    }
  }
});

emitDecoratorMetadata

true | false (default)

Set to true to pass --emitDecoratorMetadata to the compiler. If set to true, TypeScript will emit type information about type and parameter decorators, so it's available at runtime.

Used by tools like Angular. You will probably need to import the reflect-metadata package in your app when using this feature.

This is only available in TypeScript 1.5 and higher. If enabled, will automatically enable experimentalDecorators

grunt.initConfig({
  ts: {
    options: {
      emitDecoratorMetadata: true
    }
  }
});

esModuleInterop

true | false (default)

A new compatability mode to enable consistent runtime behavior with Babel and Webpack with regards to callable default ES module imports. See the TypeScript 2.7 Anouncement blog post for more details.

grunt.initConfig({
  ts: {
    options: {
      esModuleInterop: true
    }
  }
});

emitGruntEvents

true | false (default)

Set to true to emit events in Grunt upon significant events in grunt-ts. This is used by the task validate_failure_count in the Gruntfile.js of grunt-ts itself. Currently, the only supported event is grunt-ts.failure which will be raised upon a failed build if emitGruntEvents is true. This is only available in grunt-ts 5.2.0 or higher.

grunt.initConfig({
  ts: {
    options: {
      emitGruntEvents: true
    }
  }
});

Example usage:

grunt.event.on('grunt-ts.failure', function() {
    console.log('It failed!!!!!!');
});

experimentalAsyncFunctions

true | false (default)

Enable support for experimental proposed ECMAScript async functionality. This is only available in TypeScript 1.6 and higher in 'es6' mode.

grunt.initConfig({
  ts: {
    options: {
      experimentalAsyncFunctions: true,
      target: 'es6'
    }
  }
});

experimentalDecorators

true | false (default)

Enable support for experimental proposed ECMAScript decorators. This is only available in TypeScript 1.5 and higher.

grunt.initConfig({
  ts: {
    options: {
      experimentalDecorators: true
    }
  }
});

failOnTypeErrors

true (default) | false

TypeScript has two types of errors: emit preventing and non-emit preventing. Generally, type errors do not prevent the JavaScript emit. Therefore, it can be useful to allow the Grunt pipeline to continue even if there are type errors because tsc will still generate JavaScript.

If failOnTypeErrors is set to false, grunt-ts will not halt the Grunt pipeline if a TypeScript type error is encountered. Note that syntax errors or other general tsc errors will always halt the pipeline.

grunt.initConfig({
  ts: {
    options: {
      failOnTypeErrors: true
    }
  }
});

fast

"watch" (default) | "always" | "never"

If you are using external modules, grunt-ts will try to do a fast compile by default, basically only compiling what's changed. It should "just work" with the built-in file watching as well as with external tools like grunt-contrib-watch.

To do a fast compile, grunt-ts maintains a cache of hashes for TypeScript files in the .tscache folder to detect changes (needed for external watch tool support). It also creates a .baseDir.ts file at the root, passing it to the compiler to make sure that --outDir is always respected in the generated JavaScript.

You can customize the behaviour of grunt-ts fast.

If you are using files, grunt-ts can't do a fast compile. You should set fast to 'never'.

grunt.initConfig({
  ts: {
    options: {
      // disable the grunt-ts fast feature
      fast: 'never'
    }
  }
});

forceConsistentCasingInFileNames

When set to true, disallows inconsistently-cased references to the same file. For example, when using ES6-style imports, importing a file as "./MyLibrary" in one file and "./mylibrary" in another.

grunt.initConfig({
  ts: {
    default: {
      src: ["**/*.ts", "!node_modules/**"],
      options: {
        forceConsistentCasingInFileNames: true
      }
    }
  }
});

htmlModuleTemplate

Grunt-ts supports compilation of .html file content to TypeScript variables which is explained in detail here. The htmlModuleTemplate target property allows the developer to define a namespace for the templates. See also html and htmlVarTemplate.

//Note: incomplete - combine with html and htmlVarTemplate
grunt.initConfig({
  ts: {
    default: {
      options: {
        //MyTemplate.html will be accessible as HtmlTemplates.MyTemplate
        htmlModuleTemplate: 'HtmlTemplates.<%= filename %>'
      }
    }
  }
});

htmlVarTemplate

Grunt-ts supports compilation of .html file content to TypeScript variables which is explained in detail here. The htmlVarTemplate target property allows the developer to define a property name for the template contents. See also html and htmlModuleTemplate.

//Note: incomplete - combine with html and htmlModuleTemplate
grunt.initConfig({
  ts: {
    default: {
      options: {
        //HTML template objects will expose their content via a property called markup.
        htmlVarTemplate: 'markup'
      }
    }
  }
});

htmlOutDir

Sets a root for output of transformed-to-TypeScript HTML files. See detailed explanation of grunt-ts HTML template support.

//Note: incomplete - combine with html and src/files/etc.
grunt.initConfig({
  ts: {
    default: {
      options: {
        htmlOutDir: 'generatedHtml'
      }
    }
  }
});

htmlOutDirFlatten

Will flatten the transformed HTML files to a single folder. See detailed explanation of grunt-ts HTML template support.

//Note: incomplete - combine with html and src/files/etc.
grunt.initConfig({
  ts: {
    default: {
      options: {
        htmlOutDir: 'generatedHtml',
        htmlOutDirFlatten: true
      }
    }
  }
});

htmlOutputTemplate

Grunt-ts supports compilation of .html file content to TypeScript variables which is explained in detail here. The htmlOutputTemplate target property allows the developer to override the internally defined output template to a custom one, useful if one would like to define the HTML output as an external modules, for example.

Three variables can be used in the template, namely:

• "<%= modulename %>" - This variable will be replaced with the value of the htmlModuleTemplate option.
• "<%= varname %>" - This variable will be replaced with the value of the htmlVarTemplate option.
• "<%= content %>" - This variable will be replaced with the content of the HTML file.

//Note: Outputs an external module
grunt.initConfig({
  ts: {
    default: {
      options: {
        //HTML template objects will expose their content via a property called markup.
        htmlVarTemplate: 'markup',
        htmlModuleTemplate: 'html',
        htmlOutputTemplate: '/* tslint:disable:max-line-length */ \n\
          export module <%= modulename %> {\n\
              export var <%= varname %> = \'<%= content %>\';\n\
          }\n'
      }
    }
  }
});

inlineSourceMap

true | false (default)

When true, TypeScript will emit source maps inline at the bottom of each JS file, instead of emitting a separate .js.map file. If this option is used with sourceMap, inlineSourceMap will win.

grunt.initConfig({
  ts: {
    default: {
      options: {
        inlineSourceMap: true
      }
    }
  }
});

inlineSources

true | false (default)

When true, TypeScript will emit TypeScript sources "inline". This must be used with either inlineSourceMap or sourceMap. When used with inlineSourceMap, the TypeScript sources and the source map itself are included in a Base64-encoded string in a comment at the end of the emitted JavaScript file. When used with sourceMap, the escaped TypeScript sources are included in the .js.map file itself under a sourcesContent property.

grunt.initConfig({
  ts: {
    default: {
      options: {
        inlineSources: true,
        inlineSourceMap: true
      }
    }
  }
});

isolatedModules

true | false (default)

When true, makes scenarios that break single-file transpilation into an error. See https://github.com/Microsoft/TypeScript/issues/2499 for more details. If you are using TypeScript 1.5, and fast compilation, it is ideal to use this to take advantage of future compilation optimizations.

grunt.initConfig({
  ts: {
    default: {
      options: {
        isolatedModules: true
      }
    }
  }
});

jsx

`'react'` (default) | `'preserve'`

Specify the JSX code generation style. Documentation is here: TypeScript Wiki - JSX.

grunt.initConfig({
  ts: {
    options: {
      jsx: 'preserve'
    }
  }
});

lib

List of library files to be included in the compilation. If --lib is not specified a default library is injected.

grunt.initConfig({
  ts: {
    options: {
      lib: ['es2015']
    }
  }
});

locale

Specify culture string for error messages - will pass the --locale switch. Requires appropriate TypeScript error messages file to be present (see TypeScript documentation for more details).

grunt.initConfig({
  ts: {
    default: {
      options: {
        locale: "ja-jp"
      }
    }
  }
});

mapRoot

Specifies the root for where .js.map sourcemap files should be referenced. This is useful if you intend to move your .js.map files to a different location. Leave this blank or omit entirely if the .js.map files will be deployed to the same folder as the corresponding .js files. See also sourceRoot.

grunt.initConfig({
  ts: {
    default: {
      options: {
        //When abc.ts is compiled to abc.js, it will reference /maps/abc.js.map
        mapRoot: "/maps"
      }
    }
  }
});

module

"amd" | "commonjs" | "system" | "umd" | "es6" | "es2015" | "" (default) | "none" (same behavior as "")

Specifies if TypeScript should emit AMD, CommonJS, SystemJS, "ES6", or UMD-style external modules. Has no effect if internal modules are used. Note - this should not be used in combination with out prior to TypeScript 1.8 because the TypeScript compiler does not support concatenation of external modules; consider using a module bundler like WebPack, Browserify, or Require's r.js to concatenate external modules.

grunt.initConfig({
  ts: {
    default: {
      options: {
        module: "amd"
      }
    }
  }
});

moduleResolution

"node" | "classic" (default)

New in TypeScript 1.6. TypeScript is gaining support for resolving definition files using rules similar to common JavaScript module loaders. The first new one is support for CommonJS used by NodeJS, which is why this parameter is called "node" The "node" setting performs an extra check to see if a definition file exists in the node_modules/modulename folder if a TypeScript definition can't be found for an imported module. if this is not desired, set this setting to "classic".

On Defaults. When using --module commonjs the default --moduleResolution will be node. For all other --module options the default is --moduleResolution classic. If specified, the specified value will always be used.

grunt.initConfig({
  ts: {
    default: {
      options: {
        moduleResolution: "classic"
      }
    }
  }
});

newLine

"CRLF" | "LF" | "" (default)

Will force TypeScript to use the specified newline sequence. Grunt-ts will also use this newline sequence for transforms. If not specified, TypeScript and grunt-ts use the OS default.

grunt.initConfig({
  ts: {
    default: {
      options: {
        newLine: "CRLF"
      }
    }
  }
});

noEmit

true | false (default)

Set to true to pass --noEmit to the compiler. If set to true, TypeScript will not emit JavaScript regardless of if the compile succeeds or fails.

grunt.initConfig({
  ts: {
    default: {
      options: {
        noEmit: true
      }
    }
  }
});

noEmitHelpers

true | false (default)

Set to true to pass --noEmitHelpers to the compiler. If set to true, TypeScript will not emit JavaScript helper functions such as __extends. This is for very advanced users who wish to provide their own implementation of the TypeScript runtime helper functions.

grunt.initConfig({
  ts: {
    default: {
      options: {
        noEmitHelpers: true
      }
    }
  }
});

noEmitOnError

true | false (default)

Set to true to pass --noEmitOnError to the compiler. If set to true, TypeScript will not emit JavaScript if there is a type error. This flag does not affect the Grunt pipeline; to force the Grunt pipeline to continue (or halt) in the presence of TypeScript type errors, see failOnTypeErrors.

grunt.initConfig({
  ts: {
    default: {
      options: {
        noEmitOnError: true
      }
    }
  }
});

noFallthroughCasesInSwitch

true | false (default)

Report errors for fallthrough cases in switch statement.

grunt.initConfig({
  ts: {
    default: {
      src: ["**/*.ts", "!node_modules/**"],
      options: {
        noFallthroughCasesInSwitch: true
      }
    }
  }
});

noImplicitAny

true | false (default)

Set to true to pass --noImplicitAny to the compiler. Requires more strict type checking. If noImplicitAny is enabled, TypeScript will raise a type error whenever it is unable to infer the type of a variable. By default, grunt-ts will halt the Grunt pipeline on type errors. See failOnTypeErrors for more info.

grunt.initConfig({
  ts: {
    default: {
      options: {
        noImplicitAny: true
      }
    }
  }
});

noImplicitReturns

true | false (default)

Report error when not all code paths in function return a value.

grunt.initConfig({
  ts: {
    default: {
      options: {
        noImplicitReturns: true
      }
    }
  }
});

noImplicitThis

true | false (default)

Set to true to pass --noImplicitThis to the compiler. Requires more strict type checking. Raise error on this expressions with an implied any type.

grunt.initConfig({
  ts: {
    default: {
      options: {
        noImplicitThis: true
      }
    }
  }
});

noImplicitGenericChecks

true | false (default)

Set to true to pass --noImplicitGenericChecks to the compiler. Disables strict checking of generic signatures in function types.

grunt.initConfig({
  ts: {
    default: {
      options: {
        noImplicitGenericChecks: true
      }
    }
  }
});

noLib

true | false (default)

Specify this option if you do not want the lib.d.ts to be loaded by the TypeScript compiler. Generally this is used to allow you to manually specify your own lib.d.ts.

grunt.initConfig({
  ts: {
    default: {
      options: {
        noLib: true
      }
    }
  }
});

noResolve

true | false (default)

Do not add triple-slash references or module import targets to the list of compiled files.

grunt.initConfig({
  ts: {
    options: {
      noResolve: true
    }
  }
});

preserveConstEnums

true | false (default)

Set to true to pass --preserveConstEnums to the compiler. If set to true, TypeScript will emit code that allows other JavaScript code to use the enum. If false (the default), TypeScript will inline the enum values as magic numbers with a comment in the emitted JS.

grunt.initConfig({
  ts: {
    default: {
      options: {
        preserveConstEnums: true
      }
    }
  }
});

preserveSymlinks

true | false (default)

Set to true to pass --preserveSymlinks to the compiler. If set, TypeScript will not resolve symlinks to their real path; instead it will treat a symlinked file like a real one.

grunt.initConfig({
  ts: {
    default: {
      options: {
        preserveSymlinks: true
      }
    }
  }
});

pretty

true | false (default)

Stylize errors and messages using color and context.

grunt.initConfig({
  ts: {
    default: {
      options: {
        pretty: true
      }
    }
  }
});

reactNamespace

string

Specifies the object invoked for createElement and __spread when targeting 'react' JSX emit. Requires TypeScript 1.8 or higher and grunt-ts 5.5 or higher.

grunt.initConfig({
  ts: {
    options: {
      rootDir: "src/app"
    }
  }
});

removeComments

true (default)| false

Removes comments in the emitted JavaScript if set to true. Preserves comments if set to false. Note that if comments and removeComments are both used, the value of removeComments will win; regardless, please don't do this as it is just confusing to everyone.

grunt.initConfig({
  ts: {
    options: {
      removeComments: false //preserves comments in output.
    }
  }
});

rootDir

string

Affects the creation of folders inside the outDir location. rootDir allows manually specifying the desired common root folder when used in combination with outDir. Otherwise, TypeScript attempts to calculate this automatically. Not specifying rootDir can result in outDir not matching structure of src folder when using fast compilation. baseDir provides a poor man's version of rootDir for those using TypeScript < 1.5.

grunt.initConfig({
  ts: {
    options: {
      rootDir: "src/app"
    }
  }
});

skipDefaultLibCheck

true | false (default)

Don't check a user-defined default lib file's validity. This switch is deprecated in TypeScript 2.5+ (use skipLibCheck instead).

grunt.initConfig({
  ts: {
    default: {
      options: {
        skipDefaultLibCheck: true
      }
    }
  }
});

skipLibCheck

true | false (default)

Skip type checking of all declaration files (*.d.ts).

grunt.initConfig({
  ts: {
    default: {
      options: {
        skipLibCheck: true
      }
    }
  }
});

strict

true | false (default)

The strict property is a macro to enable all of the strict checks in TypeScript

grunt.initConfig({
  ts: {
    default: {
      options: {
        strict: true
      }
    }
  }
});

strictFunctionTypes

true | false (default)

Enforce contravariant function parameter comparison. Under --strictFunctionTypes, any function type that doesn't originate from a method has its parameters compared contravariantly.

grunt.initConfig({
  ts: {
    default: {
      options: {
        strictFunctionTypes: true
      }
    }
  }
});

strictNullChecks

true | false (default)

In strict null checking mode, the null and undefined values are not in the domain of every type and are only assignable to themselves and any (the one exception being that undefined is also assignable to void).

grunt.initConfig({
  ts: {
    default: {
      options: {
        strictNullChecks: true
      }
    }
  }
});

strictPropertyInitialization

true | false (default)

The strictPropertyInitialization property ensures that properties are initialized before use

grunt.initConfig({
  ts: {
    default: {
      options: {
        strictPropertyInitialization: true
      }
    }
  }
});

sourceMap

true (default) | false

If true, grunt-ts will instruct tsc to emit source maps (.js.map files). If this option is used with inlineSourceMap, inlineSourceMap will win.

grunt.initConfig({
  ts: {
    default: {
      options: {
        sourceMap: true
      }
    }
  }
});

sourceRoot

The sourceRoot to use in the emitted source map files. Allows mapping moved .js.map files back to the original TypeScript files. See also mapRoot.

grunt.initConfig({
  ts: {
    default: {
      options: {
        sourceRoot: "/dev"
      }
    }
  }
});

stripInternal

Use stripInternal to prevent the emit of members marked as @internal via a comment. For example:

/* @internal */
export class MyClass {
}

grunt.initConfig({
  ts: {
    default: {
      options: {
        sourceRoot: "/dev"
      }
    }
  }
});

suppressExcessPropertyErrors

true | false (default)

Set to true to disable strict object literal assignment checking (experimental). See https://github.com/Microsoft/TypeScript/pull/4484 for more details.

grunt.initConfig({
  ts: {
    default: {
      options: {
        suppressExcessPropertyErrors: true
      }
    }
  }
});

suppressImplicitAnyIndexErrors

true | false (default)

Set to true to pass --suppressImplicitAnyIndexErrors to the compiler. If set to true, TypeScript will allow access to properties of an object by string indexer when --noImplicitAny is active, even if TypeScript doesn't know about them. This setting has no effect unless --noImplicitAny is active.

grunt.initConfig({
  ts: {
    default: {
      options: {
        suppressImplicitAnyIndexErrors: true,
        noImplicitAny: true
      }
    }
  }
});

For example, the following code would not compile with --noImplicitAny alone, but it would be legal with --noImplicitAny and --suppressImplicitAnyIndexErrors both enabled:

interface person {
    name: string;
}

var p : person = { name: "Test" };
p["age"] = 101;  //property age does not exist on interface person.
console.log(p["age"]);

emitDecoratorMetadata

true | false (default)

Set to true to pass --emitDecoratorMetadata to the compiler. If set to true, TypeScript will emit type information about type and parameter decorators, so it's available at runtime.

Used by tools like Angular. You will probably need to import the reflect-metadata package in your app when using this feature.

target

"es5" (default) | "es3" | "es6"

Allows the developer to specify if they are targeting ECMAScript version 3, 5, or 6. Support for es6 emit was added in TypeScript 1