fix: replicate the original action's test-project auto-detection

Real gap caught by live CI (Builds - MacOS's 6000.0.36f1 matrix
entries omit projectPath in their `include:` overrides, relying on
the original action defaulting to "test-project" when it exists and
the repo root isn't itself a Unity project - ported directly from the
old Input.projectPath getter). Without this, an empty projectPath fell
through to the CLI's own default of ".", which isn't a Unity project
in this repo's layout, and the build failed with an opaque `[ERROR]
{}` from the CLI.

resolve-project-path.ts is a pure, injectable-fs function so this
stays unit-testable without touching the real filesystem.

dist/index.js

@@ -279,10 +279,13 @@ exports.run = void 0;
 // UNITY_LICENSE, UNITY_LICENSING_SERVER) are read by the CLI itself from
 // its own process environment - never passed as CLI arguments, since argv
 // can leak through process listings and command-logging.
+const fs = __importStar(__nccwpck_require__(7561));
+const path = __importStar(__nccwpck_require__(9411));
 const core = __importStar(__nccwpck_require__(2186));
 const exec = __importStar(__nccwpck_require__(1514));
 const build_args_1 = __nccwpck_require__(89);
 const download_cli_1 = __nccwpck_require__(3431);
+const resolve_project_path_1 = __nccwpck_require__(2833);
 async function run() {
     try {
         const unityVersion = core.getInput('unityVersion') || 'auto';
@@ -293,7 +296,14 @@ async function run() {
         }
         const cliVersion = core.getInput('cliVersion') || 'latest';
         const cliPath = await (0, download_cli_1.downloadCli)(cliVersion);
-        const args = (0, build_args_1.buildCliArgs)({ getInput: (name) => core.getInput(name) });
+        const projectPath = (0, resolve_project_path_1.resolveProjectPath)({
+            input: core.getInput('projectPath'),
+            existsSync: fs.existsSync,
+            joinPath: path.join,
+        });
+        const args = (0, build_args_1.buildCliArgs)({
+            getInput: (name) => (name === 'projectPath' ? projectPath : core.getInput(name)),
+        });
         const exitCode = await exec.exec(cliPath, args, { ignoreReturnCode: true });
         // Matches the original action's engineExitCode output: 0 on success,
         // otherwise the exit code of whichever step (activation or build)
@@ -317,6 +327,27 @@ if (process.env.NODE_ENV !== 'test') {
 }
 
 
+/***/ }),
+
+/***/ 2833:
+/***/ ((__unused_webpack_module, exports) => {
+
+"use strict";
+
+Object.defineProperty(exports, "__esModule", ({ value: true }));
+exports.resolveProjectPath = void 0;
+function resolveProjectPath({ input, existsSync, joinPath }) {
+    if (input)
+        return input.replace(/\/$/, '');
+    const hasTestProject = existsSync(joinPath('test-project', 'ProjectSettings', 'ProjectVersion.txt'));
+    const hasRootProject = existsSync(joinPath('ProjectSettings', 'ProjectVersion.txt'));
+    if (hasTestProject && !hasRootProject)
+        return 'test-project';
+    return '';
+}
+exports.resolveProjectPath = resolveProjectPath;
+
+
 /***/ }),
 
 /***/ 7799:

src/index.ts

@@ -8,10 +8,13 @@
 // UNITY_LICENSE, UNITY_LICENSING_SERVER) are read by the CLI itself from
 // its own process environment - never passed as CLI arguments, since argv
 // can leak through process listings and command-logging.
+import * as fs from 'node:fs';
+import * as path from 'node:path';
 import * as core from '@actions/core';
 import * as exec from '@actions/exec';
 import { buildCliArgs } from './build-args';
 import { downloadCli } from './download-cli';
+import { resolveProjectPath } from './resolve-project-path';
 
 export async function run() {
   try {
@@ -27,7 +30,15 @@ export async function run() {
     const cliVersion = core.getInput('cliVersion') || 'latest';
     const cliPath = await downloadCli(cliVersion);
 
-    const args = buildCliArgs({ getInput: (name) => core.getInput(name) });
+    const projectPath = resolveProjectPath({
+      input: core.getInput('projectPath'),
+      existsSync: fs.existsSync,
+      joinPath: path.join,
+    });
+
+    const args = buildCliArgs({
+      getInput: (name) => (name === 'projectPath' ? projectPath : core.getInput(name)),
+    });
 
     const exitCode = await exec.exec(cliPath, args, { ignoreReturnCode: true });
 

src/resolve-project-path.test.ts

@@ -0,0 +1,53 @@
+import { describe, it, expect } from 'vitest';
+import { resolveProjectPath } from './resolve-project-path';
+
+function fsOf(existingPaths: string[]) {
+  return {
+    joinPath: (...segments: string[]) => segments.join('/'),
+    existsSync: (candidate: string) => existingPaths.includes(candidate),
+  };
+}
+
+describe('resolveProjectPath', () => {
+  it('returns the explicit input unchanged when given', () => {
+    const result = resolveProjectPath({
+      input: 'my-project',
+      ...fsOf(['test-project/ProjectSettings/ProjectVersion.txt']),
+    });
+
+    expect(result).toBe('my-project');
+  });
+
+  it('strips a trailing slash from an explicit input', () => {
+    const result = resolveProjectPath({ input: 'my-project/', ...fsOf([]) });
+
+    expect(result).toBe('my-project');
+  });
+
+  it('defaults to "test-project" when it looks like a Unity project and the repo root does not', () => {
+    const result = resolveProjectPath({
+      input: '',
+      ...fsOf(['test-project/ProjectSettings/ProjectVersion.txt']),
+    });
+
+    expect(result).toBe('test-project');
+  });
+
+  it('does not default to "test-project" when the repo root is itself a Unity project', () => {
+    const result = resolveProjectPath({
+      input: '',
+      ...fsOf([
+        'test-project/ProjectSettings/ProjectVersion.txt',
+        'ProjectSettings/ProjectVersion.txt',
+      ]),
+    });
+
+    expect(result).toBe('');
+  });
+
+  it('returns empty (letting the cli default to ".") when neither location looks like a Unity project', () => {
+    const result = resolveProjectPath({ input: '', ...fsOf([]) });
+
+    expect(result).toBe('');
+  });
+});

src/resolve-project-path.ts

@@ -0,0 +1,29 @@
+/**
+ * Replicates the original action's projectPath auto-detection: when
+ * projectPath isn't given explicitly, and a test-project/ directory looks
+ * like a Unity project while the current directory doesn't, default to
+ * "test-project" instead of the repo root. See the original
+ * Input.projectPath getter this is ported from.
+ */
+export interface ResolveProjectPathOptions {
+  input: string;
+  existsSync(path: string): boolean;
+  joinPath(...segments: string[]): string;
+}
+
+export function resolveProjectPath({
+  input,
+  existsSync,
+  joinPath,
+}: ResolveProjectPathOptions): string {
+  if (input) return input.replace(/\/$/, '');
+
+  const hasTestProject = existsSync(
+    joinPath('test-project', 'ProjectSettings', 'ProjectVersion.txt'),
+  );
+  const hasRootProject = existsSync(joinPath('ProjectSettings', 'ProjectVersion.txt'));
+
+  if (hasTestProject && !hasRootProject) return 'test-project';
+
+  return '';
+}