feat(node): Add a function to resolve entry point type (#14352)

Author: timfish

packages/node/src/utils/entry-point.ts

@@ -0,0 +1,66 @@
+import { resolve } from 'node:path';
+import { defaultStackParser } from '../sdk/api';
+
+export interface ProcessInterface {
+  execArgv: string[];
+  argv: string[];
+  cwd: () => string;
+}
+
+export interface ProcessArgs {
+  appPath: string;
+  importPaths: string[];
+  requirePaths: string[];
+}
+
+/**
+ * Parses the process arguments to determine the app path, import paths, and require paths.
+ */
+export function parseProcessPaths(proc: ProcessInterface): ProcessArgs {
+  const { execArgv, argv, cwd: getCwd } = proc;
+  const cwd = getCwd();
+  const appPath = resolve(cwd, argv[1] || '');
+
+  const joinedArgs = execArgv.join(' ');
+  const importPaths = Array.from(joinedArgs.matchAll(/--import[ =](\S+)/g)).map(e => resolve(cwd, e[1] || ''));
+  const requirePaths = Array.from(joinedArgs.matchAll(/--require[ =](\S+)/g)).map(e => resolve(cwd, e[1] || ''));
+
+  return { appPath, importPaths, requirePaths };
+}
+
+/**
+ * Gets the current entry point type.
+ *
+ * `app` means this function was most likely called via the app entry point.
+ * `import` means this function was most likely called from an --import cli arg.
+ * `require` means this function was most likely called from a --require cli arg.
+ * `unknown` means we couldn't determine for sure.
+ */
+export function getEntryPointType(proc: ProcessInterface = process): 'import' | 'require' | 'app' | 'unknown' {
+  const filenames = defaultStackParser(new Error().stack || '')
+    .map(f => f.filename)
+    .filter(Boolean) as string[];
+
+  const { appPath, importPaths, requirePaths } = parseProcessPaths(proc);
+
+  const output = [];
+
+  if (appPath && filenames.includes(appPath)) {
+    output.push('app');
+  }
+
+  if (importPaths.some(p => filenames.includes(p))) {
+    output.push('import');
+  }
+
+  if (requirePaths.some(p => filenames.includes(p))) {
+    output.push('require');
+  }
+
+  // We only only return anything other than 'unknown' if we only got one match.
+  if (output.length === 1) {
+    return output[0] as 'import' | 'require' | 'app';
+  }
+
+  return 'unknown';
+}

packages/node/test/utils/entry-point.test.ts

@@ -0,0 +1,102 @@
+import type { ProcessArgs, ProcessInterface } from '../../src/utils/entry-point';
+import { getEntryPointType, parseProcessPaths } from '../../src/utils/entry-point';
+
+const PROCESS_ARG_TESTS: [ProcessInterface, ProcessArgs][] = [
+  [
+    { cwd: () => '/user/tim/docs', argv: ['/bin/node', 'app.js'], execArgv: ['--import', './something.js'] },
+    { appPath: '/user/tim/docs/app.js', importPaths: ['/user/tim/docs/something.js'], requirePaths: [] },
+  ],
+  [
+    {
+      cwd: () => '/user/tim/docs',
+      argv: ['/bin/node', 'app.js'],
+      execArgv: ['--import', './something.js', '--import=./else.js'],
+    },
+    {
+      appPath: '/user/tim/docs/app.js',
+      importPaths: ['/user/tim/docs/something.js', '/user/tim/docs/else.js'],
+      requirePaths: [],
+    },
+  ],
+  [
+    {
+      cwd: () => '/user/tim/docs',
+      argv: ['/bin/node', 'app.js'],
+      execArgv: ['--require', './something.js', '--import=else.js'],
+    },
+    {
+      appPath: '/user/tim/docs/app.js',
+      importPaths: ['/user/tim/docs/else.js'],
+      requirePaths: ['/user/tim/docs/something.js'],
+    },
+  ],
+  [
+    {
+      cwd: () => '/user/tim/docs',
+      argv: ['/bin/node', 'app.js'],
+      execArgv: ['--require=here/something.js'],
+    },
+    {
+      appPath: '/user/tim/docs/app.js',
+      importPaths: [],
+      requirePaths: ['/user/tim/docs/here/something.js'],
+    },
+  ],
+];
+
+describe('getEntryPointType', () => {
+  it.each(PROCESS_ARG_TESTS)('parseProcessArgs', (input, output) => {
+    const result = parseProcessPaths(input);
+    expect(result).toStrictEqual(output);
+  });
+
+  it('app absolute', () => {
+    const ctx = getEntryPointType({
+      cwd: () => __dirname,
+      argv: ['/bin/node', __filename],
+      execArgv: [],
+    });
+
+    expect(ctx).toEqual('app');
+  });
+
+  it('app relative', () => {
+    const ctx = getEntryPointType({
+      cwd: () => __dirname,
+      argv: ['/bin/node', 'entry-point.test.ts'],
+      execArgv: [],
+    });
+
+    expect(ctx).toEqual('app');
+  });
+
+  it('import absolute', () => {
+    const ctx = getEntryPointType({
+      cwd: () => __dirname,
+      argv: ['/bin/node', 'app.ts'],
+      execArgv: ['--import', __filename],
+    });
+
+    expect(ctx).toEqual('import');
+  });
+
+  it('import relative', () => {
+    const ctx = getEntryPointType({
+      cwd: () => __dirname,
+      argv: ['/bin/node', 'app.ts'],
+      execArgv: ['--import', './entry-point.test.ts'],
+    });
+
+    expect(ctx).toEqual('import');
+  });
+
+  it('require relative', () => {
+    const ctx = getEntryPointType({
+      cwd: () => __dirname,
+      argv: ['/bin/node', 'app.ts'],
+      execArgv: ['--require', './entry-point.test.ts'],
+    });
+
+    expect(ctx).toEqual('require');
+  });
+});

packages/node/tsconfig.json

@@ -4,7 +4,7 @@
   "include": ["src/**/*"],
 
   "compilerOptions": {
-    "lib": ["es2018"],
+    "lib": ["es2018", "es2020.string"],
     "module": "Node16"
   }
 }