Compiling TypeScript into JavaScript

Because browsers and Node.js process only JavaScript, you have to compile your TypeScript code before running or debugging it.

Compilation can also produce source maps that set correspondence between your TypeScript code and the JavaScript code that is actually executed.

GoLand comes with a built-in TypeScript compiler. By default, it outputs generated JavaScript files and sourcemaps next to the TypeScript file.

Compilation is invoked with the Compile actions from the TypeScript widget on the Status toolbar as described in Compile TypeScript code below.

Compilation errors are reported in the TypeScript Tool Window. This list is not affected by changes you make to your code and is updated only when you invoke compilation again.

The tool window shows up only after you first compile your TypeScript code manually. After that the tool window is accessible via View | Tool Windows | TypeScript on the main menu or via the tool window bar.

Before you start

Press Control+Alt+S to open the IDE settings and then select Languages & Frameworks | TypeScript.
Make sure the TypeScript Language Service checkbox is selected.

Create and configure tsconfig.json files

By default, the built-in compiler does not create source maps that will let you step through your TypeScript code during a debugging session. The compiler also by default processes either the TypeScript file in the active editor tab or all TypeScript files from the current project.

With a tsconfig.json file, you can modify this default behavior to generate source maps and compile only files from a custom scope.

Create a tsconfig.json file

In the Project tool window, select the folder where your TypeScript code is (most often it is the project root folder) and then select New | tsconfig.json File from the context menu.
To generate source maps during compilation, make sure the sourceMap property is set to true.
Optionally:
To override the default compilation scope, which is the entire project, add the files property and type the names of the files to process in the following format:
"files" : ["<file1.ts>","<file2.ts>"],

Configure the scope for tsconfig.json

You may need to apply different TypeScript configurations to different files in your project.

It is not a problem if you arrange your sources so that all the files in each folder should be processed according to the same configuration. In such case you only have to create a separate tsconfig.json for each folder.

However if you want to apply different rules to the files that are stored in the same folder, you need to create several configuration files and configure scopes for them.

Create as many tsconfig*.json configuration files a s you need.
Open the Settings dialog (Control+Alt+S), go to Editor | File Types, and make sure the names of all these files match the patterns from the Typescript config file name patterns list.
In each *tsconfig*.json, specify the files to be processed according to its settings:
- List the file names explicitly in the files field:
  "files" : ["<file1.ts>","<file2.ts>"],
  Learn more from TSConfig Reference: Files.
- In the include field, specify the file names or patterns:
  "include" : ["<pattern1>, <pattern2>"]
  Learn more from TSConfig Reference: Include.
- To skip some files whose names match the patterns listed in the include field, list their names or patterns in the exclude field:
  "exclude" : ["<pattern3>, <pattern4>"]
  Learn more from TSConfig Reference: Exclude.

Compile TypeScript code

You can invoke compilation manually or have GoLand compile your code automatically every time the code is changed.

Alternatively, you can configure a build process, for example, with webpack, babel, or another tool.

Manual compilation

Click the TypeScript widget on the Status bar.
The widget is shown on the Status bar all the time after you have opened a TypeScript file in the editor.
Select Compile, and then select one of the following options:
- To compile the TypeScript code of the entire application, select Compile All.
  Alternatively, select Compile TypeScript from the context menu of any open TypeScript file.
  You can also press Control+Shift+A and choose Compile TypeScript from the list.
- To compile one file, open it in the editor, and select the path to the file from the list in the TypeScript widget.
- To compile files from a custom scope, make sure they are listed in the files property of your tsconfig.json as described above. Click the TypeScript widget on the Status bar, select Compile, and then select the path to tsconfig.json.

Automatic compilation on changes

Open the Languages & Frameworks | TypeScript page of the IDE settings Control+Alt+S and select the Recompile on changes checkbox.

Last modified: 23 August 2023