feat: migrate from neverthrow to effect

Author: velut

package.json

@@ -58,10 +58,10 @@
   },
   "dependencies": {
     "@microsoft/tsdoc": "^0.14.2",
+    "effect": "^2.4.1",
     "execa": "^8.0.1",
     "memoize": "^10.0.0",
     "natural-orderby": "^3.0.2",
-    "neverthrow": "^6.1.0",
     "pathe": "^1.1.2",
     "prettier": "^3.2.5",
     "read-pkg": "^9.0.1",

pnpm-lock.yaml

@@ -1,57 +1,55 @@
+import { Effect } from "effect";
 import fs from "node:fs/promises";
 import { join } from "pathe";
 import { temporaryDirectoryTask } from "tempy";
 import { expect, test } from "vitest";
-import { createProject } from "./create-project";
-import { ProjectError } from "./errors";
+import { createProject, type CreateProjectOptions } from "./create-project";
+
+const _createProject = (options: CreateProjectOptions) =>
+  Effect.runPromise(createProject(options));
 
 test("no cwd", async () => {
   await temporaryDirectoryTask(async (dir) => {
-    const project = createProject({
-      indexFilePath: "./no-such-file.ts",
-      cwd: join(dir, "this-dir-does-not-exist"),
-    });
-    expect(project.isErr()).toBe(true);
-    expect(project._unsafeUnwrapErr() instanceof ProjectError).toBe(true);
+    await expect(
+      _createProject({
+        indexFilePath: "./this-file-does-not-exist.ts",
+        cwd: join(dir, "this-dir-does-not-exist"),
+      }),
+    ).rejects.toThrow();
   });
 });
 
 test("no index file", async () => {
   await temporaryDirectoryTask(async (dir) => {
-    const project = createProject({
-      indexFilePath: "./no-such-file.ts",
-      cwd: dir,
-    });
-    expect(project.isErr()).toBe(true);
-    expect(project._unsafeUnwrapErr() instanceof ProjectError).toBe(true);
+    await expect(
+      _createProject({
+        indexFilePath: "./this-file-does-not-exist.ts",
+        cwd: dir,
+      }),
+    ).rejects.toThrow();
   });
 });
 
 test("with index file", async () => {
   await temporaryDirectoryTask(async (dir) => {
-    await fs.writeFile(join(dir, "./index.ts"), "export {};");
-    const project = createProject({ indexFilePath: "./index.ts", cwd: dir });
-    expect(project.isOk()).toBe(true);
+    const indexFilePath = join(dir, "./index.ts");
+    await fs.writeFile(indexFilePath, "export {};");
+    const { project } = await _createProject({ indexFilePath, cwd: dir });
     expect(
-      project
-        ._unsafeUnwrap()
-        .project.getSourceFiles()
-        .map((sf) => sf.getBaseName()),
+      project.getSourceFiles().map((sf) => sf.getBaseName()),
     ).toStrictEqual(["index.ts"]);
   });
 });
 
 test("with index file and other file", async () => {
   await temporaryDirectoryTask(async (dir) => {
-    await fs.writeFile(join(dir, "./index.ts"), "export * from './other';");
-    await fs.writeFile(join(dir, "./other.ts"), "export const a = 1;");
-    const project = createProject({ indexFilePath: "./index.ts", cwd: dir });
-    expect(project.isOk()).toBe(true);
+    const indexFilePath = join(dir, "./index.ts");
+    const otherFilePath = join(dir, "./other.ts");
+    await fs.writeFile(indexFilePath, "export * from './other';");
+    await fs.writeFile(otherFilePath, "export const a = 1;");
+    const { project } = await _createProject({ indexFilePath, cwd: dir });
     expect(
-      project
-        ._unsafeUnwrap()
-        .project.getSourceFiles()
-        .map((sf) => sf.getBaseName()),
+      project.getSourceFiles().map((sf) => sf.getBaseName()),
     ).toStrictEqual(["index.ts", "other.ts"]);
   });
 });

src/create-project.test.ts

@@ -1,63 +1,44 @@
-import { Result, err, ok } from "neverthrow";
-import process from "node:process";
+import { Effect } from "effect";
 import {
   ModuleKind,
   ModuleResolutionKind,
   Project,
   ScriptTarget,
-  SourceFile,
 } from "ts-morph";
-import { ProjectError } from "./errors";
 
 export type CreateProjectOptions = {
   indexFilePath: string;
   cwd: string;
 };
 
-export type ProjectContainer = {
-  project: Project;
-  indexFile: SourceFile;
-};
-
-export const createProject = ({
-  indexFilePath,
-  cwd,
-}: CreateProjectOptions): Result<ProjectContainer, ProjectError> => {
-  try {
-    // By default, ts-morph creates the project in the current working directory.
-    // We must change it to the temporary directory where the packages are installed,
-    // otherwise TypeScript will pick up type definitions from our local `node_modules`.
-    const startDir = process.cwd();
-    process.chdir(cwd);
-    const res = _createProject(indexFilePath);
-    process.chdir(startDir);
-    return res;
-  } catch (e) {
-    return err(new ProjectError("failed to change directories", { cause: e }));
-  }
-};
+/** @internal */
+export class ProjectError {
+  readonly _tag = "ProjectError";
+  constructor(readonly cause?: unknown) {}
+}
 
-const _createProject = (
-  indexFilePath: string,
-): Result<ProjectContainer, ProjectError> => {
-  try {
-    const project = new Project({
-      compilerOptions: {
-        // See https://github.com/dsherret/ts-morph/issues/938
-        // and https://github.com/microsoft/TypeScript/blob/master/lib/lib.esnext.full.d.ts
-        lib: ["lib.esnext.full.d.ts"],
-        target: ScriptTarget.ESNext,
-        module: ModuleKind.ESNext,
-        moduleResolution: ModuleResolutionKind.Bundler,
-      },
-    });
-    const indexFile = project.addSourceFileAtPath(indexFilePath);
-    project.resolveSourceFileDependencies();
-    return ok({
-      project,
-      indexFile,
-    });
-  } catch (e) {
-    return err(new ProjectError("failed to create project", { cause: e }));
-  }
-};
+export const createProject = ({ indexFilePath, cwd }: CreateProjectOptions) =>
+  Effect.try({
+    try: () => {
+      const project = new Project({
+        compilerOptions: {
+          // See https://github.com/dsherret/ts-morph/issues/938
+          // and https://github.com/microsoft/TypeScript/blob/master/lib/lib.esnext.full.d.ts
+          lib: ["lib.esnext.full.d.ts"],
+          target: ScriptTarget.ESNext,
+          module: ModuleKind.ESNext,
+          moduleResolution: ModuleResolutionKind.Bundler,
+          // By default, ts-morph creates a project rooted in the current working directory.
+          // We must change the `typeRoots` directory to the temporary directory
+          // where the packages are installed, otherwise TypeScript will discover
+          // `@types` packages from our local `node_modules` directory.
+          // See https://www.typescriptlang.org/tsconfig#typeRoots.
+          typeRoots: [cwd],
+        },
+      });
+      const indexFile = project.addSourceFileAtPath(indexFilePath);
+      project.resolveSourceFileDependencies();
+      return { project, indexFile };
+    },
+    catch: (e) => new ProjectError(e),
+  });