diff --git a/lib/libvips.js b/lib/libvips.js
index 4bd293dab..d0bcaca60 100644
--- a/lib/libvips.js
+++ b/lib/libvips.js
@@ -89,12 +89,13 @@ const removeVendoredLibvips = function () {
   rm(vendorPath, { recursive: true, maxRetries: 3, force: true });
 };
 
+/* istanbul ignore next */
 const pkgConfigPath = function () {
   if (process.platform !== 'win32') {
     const brewPkgConfigPath = spawnSync(
       'which brew >/dev/null 2>&1 && brew environment --plain | grep PKG_CONFIG_LIBDIR | cut -d" " -f2',
       spawnSyncOptions
-    ).stdout /* istanbul ignore next */ || '';
+    ).stdout || '';
     return [
       brewPkgConfigPath.trim(),
       env.PKG_CONFIG_PATH,
diff --git a/package.json b/package.json
index b81349c07..779c97614 100644
--- a/package.json
+++ b/package.json
@@ -92,7 +92,7 @@
     "clean": "rm -rf node_modules/ build/ vendor/ .nyc_output/ coverage/ test/fixtures/output.*",
     "test": "npm run test-lint && npm run test-unit && npm run test-licensing",
     "test-lint": "semistandard && cpplint",
-    "test-unit": "nyc --reporter=lcov --reporter=text --check-coverage --branches=100 mocha --slow=1000 --timeout=10000 ./test/unit/*.js",
+    "test-unit": "nyc --reporter=lcov --reporter=text --check-coverage --branches=100 mocha --slow=1000 --timeout=20000 ./test/unit/*.js",
     "test-licensing": "license-checker --production --summary --onlyAllow=\"Apache-2.0;BSD;ISC;MIT\"",
     "test-leak": "./test/leak/leak.sh",
     "docs-build": "documentation lint lib && node docs/build && node docs/search-index/build",