Maximum call stack size exceeded in isTypeAssignableTo when using recursive template literal types in a generic context

[mdm317]

🔎 Search Terms

Maximum call stack size exceeded in isTypeAssignableTo when using recursive template literal types in a generic context

🕗 Version & Regression Information

• This changed between versions 5.9.3

⏯ Playground Link

https://codesandbox.io/p/devbox/7ctt7z?file=%2Findex.js%3A40%2C9

💻 Code

import ts from "typescript";

const code = `

type A<T extends string> = T extends \`\${infer F}\${infer R}\`
  ? \`\${F}b\${A<R>}\`
  : "";

type B<T extends string> = T extends \`\${infer F}\${infer R}\`
  ? \`\${F}b\${B<R>}\`
  : "";

type C<T extends string> = A<T> | B<T>;

`;

const fileName = "test.ts";
const sourceFile = ts.createSourceFile(
  fileName,
  code,
  ts.ScriptTarget.Latest,
  true
);

const host = ts.createCompilerHost({});
host.getSourceFile = (name) => (name === fileName ? sourceFile : undefined);

const program = ts.createProgram([fileName], {}, host);
const checker = program.getTypeChecker();

const types = {};

ts.forEachChild(sourceFile, (node) => {
  if (ts.isTypeAliasDeclaration(node)) {
    types[node.name.escapedText] = checker.getTypeAtLocation(node);
  }
});
const typeA = types["A"];
const typeB = types["B"];
// works
console.log("isTypeAssignableTo(A, B):", checker.isTypeAssignableTo(typeA, typeB));


ts.forEachChildRecursively(sourceFile, (node) => {
  if (ts.isTypeReferenceNode(node) && ts.isUnionTypeNode(node.parent)) {
    types[node.typeName.escapedText] = checker.getTypeAtLocation(node);
  }
});
const typeAInsideGeneric = types["A"];
const typeBInsideGeneric = types["B"];

// Maximum call stack size exceeded
console.log("isTypeAssignableTo(A, B):", checker.isTypeAssignableTo(typeAInsideGeneric, typeBInsideGeneric));

🙁 Actual behavior

Maximum call stack

🙂 Expected behavior

Not occur maximum call stack

Additional information about the issue

from typescript-eslint/11824