feat: lookup project tsconfig

This looks up the default tsconfig.json file for the current project when used from the CLI, to avoid possible compliation errors. Fixes #2062

README.md

@@ -35,6 +35,8 @@ Note that different platforms (e.g. Windows) may use different path separators s
 
 Also note that you need to quote paths with `*` as otherwise the shell will expand the paths and therefore only pass the first path to the generator.
 
+By default, the command-line generator will use the `tsconfig.json` file in the current working directory, or the first parent directory that contains a `tsconfig.json` file up to the root of the filesystem. If you want to use a different `tsconfig.json` file, you can use the `--tsconfig` option. In particular, if you need to use different compilation options for types, you may want to create a separate `tsconfig.json` file for the schema generation only.
+
 ### Options
 
 ```

src/Utils/findTsConfig.ts

@@ -0,0 +1,22 @@
+import fs from "fs";
+import path from "path";
+
+/**
+ * Find the tsconfig.json file in the current working directory or any parent directory.
+ * This is the behavior from tsc: https://www.typescriptlang.org/docs/handbook/tsconfig-json.html
+ *
+ * @param directory - The directory to start searching from. Defaults to the current working directory.
+ * @param filename - The filename of the tsconfig.json file. Defaults to "tsconfig.json".
+ * @returns The path to the tsconfig.json file or undefined if no such file was found.
+ */
+export function findTsConfig(directory: string = process.cwd(), filename = "tsconfig.json"): string | undefined {
+    const tsConfigPath = path.join(directory, filename);
+    if (fs.existsSync(tsConfigPath)) {
+        return tsConfigPath;
+    }
+    const parentDir = path.dirname(directory);
+    if (parentDir === directory) {
+        return undefined;
+    }
+    return findTsConfig(parentDir, filename);
+}

test/unit/findTsConfig.test.ts

@@ -0,0 +1,53 @@
+import path from "path";
+import fs from "fs";
+import { findTsConfig } from "../../src/Utils/findTsConfig.js";
+
+jest.mock("fs");
+
+describe("findTsConfig", () => {
+    const mockCwd = "/mock/project";
+    const mockTsConfigPath = path.join(mockCwd, "tsconfig.json");
+
+    beforeEach(() => {
+        jest.resetAllMocks();
+        jest.spyOn(process, "cwd").mockReturnValue(mockCwd);
+    });
+
+    afterAll(() => {
+        jest.restoreAllMocks();
+    });
+
+    it("returns the path to the tsconfig.json file when it exists", () => {
+        (fs.existsSync as jest.Mock).mockReturnValue(true);
+        const foundTsConfig = findTsConfig();
+        expect(foundTsConfig).toBe(mockTsConfigPath);
+    });
+
+    it("returns undefined when tsconfig.json is not found in any parent directory", () => {
+        (fs.existsSync as jest.Mock).mockReturnValue(false);
+        const foundTsConfig = findTsConfig();
+        expect(foundTsConfig).toBeUndefined();
+    });
+
+    it("searches in parent directories until tsconfig.json is found", () => {
+        (fs.existsSync as jest.Mock).mockReturnValueOnce(false).mockReturnValueOnce(false).mockReturnValueOnce(true);
+
+        const expectedPath = path.join(path.dirname(path.dirname(mockCwd)), "tsconfig.json");
+        const foundTsConfig = findTsConfig();
+        expect(foundTsConfig).toBe(expectedPath);
+    });
+
+    it("returns undefined when reaching the root directory without finding tsconfig.json", () => {
+        (fs.existsSync as jest.Mock).mockReturnValue(false);
+        const foundTsConfig = findTsConfig("/");
+        expect(foundTsConfig).toBeUndefined();
+    });
+
+    it("uses the provided filename when searching for the config file", () => {
+        (fs.existsSync as jest.Mock).mockReturnValue(true);
+        const customFilename = "custom-tsconfig.json";
+        const expectedPath = path.join(mockCwd, customFilename);
+        const foundTsConfig = findTsConfig(undefined, customFilename);
+        expect(foundTsConfig).toBe(expectedPath);
+    });
+});

ts-json-schema-generator.ts

@@ -5,6 +5,7 @@ import stableStringify from "safe-stable-stringify";
 import { createGenerator } from "./factory/generator.js";
 import type { Config } from "./src/Config.js";
 import { BaseError } from "./src/Error/BaseError.js";
+import { findTsConfig } from "./src/Utils/findTsConfig.js";
 
 import pkg from "./package.json";
 
@@ -56,7 +57,7 @@ const args = new Command()
 const config: Config = {
     minify: args.minify,
     path: args.path,
-    tsconfig: args.tsconfig,
+    tsconfig: args.tsconfig ?? findTsConfig(),
     type: args.type,
     schemaId: args.id,
     expose: args.expose,