Template Test Files

When testing a type against many inputs, TSTyche can generate tests from a template file.

Usage

To mark a test file as a template, place the // @tstyche template comment directive at the top. When the directive is found, the default export is interpreted as type test text.

For example, the following:


// @tstyche template -- For documentation, see: https://tstyche.org/guides/template-test-files
 
let  = `import { expect, test } from "tstyche";
`;
 
for (const  of ["string", "number"]) {
   += `test("is ${} a string?", () => {
  expect<${}>().type.toBe<string>();
});
`;
}
 
export default ;

is interpreted as:


import { ,  } from "tstyche";
("is string a string?", () => {
  <string>()..<string>();
});
("is number a string?", () => {
  <number>()..<string>();
});

The type test text is loaded via import() and replaced programmatically under the same file name. Therefore, the template must be a TypeScript file that Node.js can execute directly without transpilation. Fortunately, running TypeScript code with Node.js is now possible .