chore: go overboard

Make the type system as smart as the function.

test/flags.test.js

@@ -1,7 +1,13 @@
 const TestCli = require('./jest-helpers/cli');
+const snapshotter = require('./snapshotter');
 
+/**
+ * @template {string} N
+ * @param {N} name
+ * @returns {`test/snapshots/flags/${N}.txt`}
+ */
 function testName(name) {
-  return `test/snapshots/flags/${name}.txt`;
+  return snapshotter.snapshotPath('flags', name);
 }
 
 test('Running with an unknown flag', async () => {

test/help.test.js

@@ -1,7 +1,13 @@
 const TestCli = require('./jest-helpers/cli');
+const snapshotter = require('./snapshotter');
 
+/**
+ * @template {string} N
+ * @param {N} name
+ * @returns {`test/snapshots/help/${N}.txt`}
+ */
 function testName(name) {
-  return `test/snapshots/help/${name}.txt`;
+  return snapshotter.snapshotPath('help', name);
 }
 
 test('--help', async () => {

test/review.test.js

@@ -1,8 +1,14 @@
 const path = require('node:path');
 const TestCli = require('./jest-helpers/cli');
+const snapshotter = require('./snapshotter');
 
+/**
+ * @template {string} N
+ * @param {N} name
+ * @returns {`test/snapshots/review/${N}.txt`}
+ */
 function testName(name) {
-  return `test/snapshots/review/${name}.txt`;
+  return snapshotter.snapshotPath('review', name);
 }
 
 test('Regular run from inside the project', async () => {

test/snapshotter.js

@@ -0,0 +1,12 @@
+/**
+ * @template {string} G
+ * @template {string} N
+ * @param {G} group
+ * @param {N} name
+ * @returns {`test/snapshots/${G}/${N}.txt`}
+ */
+function snapshotPath(group, name) {
+  return `test/snapshots/${group}/${name}.txt`;
+}
+
+module.exports = {snapshotPath};

test/suppress.test.js

@@ -1,9 +1,15 @@
 const path = require('node:path');
 const childProcess = require('node:child_process');
 const TestCli = require('./jest-helpers/cli');
+const snapshotter = require('./snapshotter');
 
+/**
+ * @template {string} N
+ * @param {N} name
+ * @returns {`test/snapshots/suppress/${N}.txt`}
+ */
 function testName(name) {
-  return `test/snapshots/suppress/${name}.txt`;
+  return snapshotter.snapshotPath('suppress', name);
 }
 
 test('Running on project with only suppressed errors remaining should not exit with failure', () => {