ember-content-mapper

Type-check .gts and .gjs files with native TypeScript 7.

This package is a TypeScript content mapper.

Requirements

• TypeScript 7.1 nightly or newer (typescript@next)
• Node 22.21.1 or newer, or Node 24.10.0 or newer
• imports must specify the file extensions

Install

pnpm add -D ember-content-mapper @glint/ember-tsc

Use

Add the mapper to tsconfig.json:

{
  "contentMappers": [
    {
      "package": "ember-content-mapper",
      "extensions": [".gts", ".gjs"],
    },
  ],
  "include": ["src"],
}

Type-check:

tsc --noEmit --runExternalCode

Options

options accepts the options of Glint's ember-template-imports environment:

{
  "contentMappers": [
    {
      "package": "ember-content-mapper",
      "extensions": [".gts", ".gjs"],
      "options": {
        "additionalGlobals": ["t"],
        "additionalSpecialForms": {},
      },
    },
  ],
}

Directives

Glint's directives work as before:

• {{! @glint-expect-error }} suppresses the diagnostics on the next line. If there are none, TypeScript reports glint2578: Unused '@glint-expect-error' directive.
• {{! @glint-ignore }} suppresses the diagnostics on the next line.
• {{! @glint-nocheck }} suppresses the diagnostics in the whole template.

Declaration files

A sibling declaration file wins over transforming the module, matching Glint: counter.gjs is typed from counter.d.gjs.ts (TypeScript 7's arbitrary-extension convention) or counter.gjs.d.ts (Glint's) when one exists. The declaration is parsed as a .ts module, so anything unbodied or uninitialized in it must use ambient (declare) syntax.

Migrating

• From TypeScript 6 and Glint 2 (ember-tsc)
• From Glint 1

Editors

• VS Code: TypeScript (Native Preview), TypeScript Nightly, and Glint 2 1.4.2 or newer, with "js/ts.experimental.useTsgo": true.
• Neovim: ember.nvim attaches TypeScript 7's LSP when tsconfig.json has contentMappers.

examples/README.md has the details.

Debug

TS_CONTENT_MAPPER_DEBUG=1 logs the JSON-RPC traffic between tsc and the mapper.

TS_CONTENT_MAPPER_WORKERS=<n> sets the number of transform workers (default: cores − 1, at most 8; 1 = main thread). tsc --extendedDiagnostics shows the wait as Content mapper request wait time.

Repository

• examples/: two Ember apps that use the mapper.
• test/test-packages/: copies of Glint's test packages, with the known differences recorded in test/test-packages/README.md.
• test/: snapshot tests of the transform, tests of the server process, LSP tests against the example app (hover, definition, completion, diagnostics, rename), and compiler mode tests (declaration emit, --build up-to-date checks, option diagnostics).

Prior art

• mdx-content-mapper, which this package follows.
• Vue's content mapper.

License

MIT