From 579bb5fad774a7f8a7790a221bfedfe087a82077 Mon Sep 17 00:00:00 2001
From: Aaron Feledy <aaron@arrow.one>
Date: Tue, 24 Feb 2026 22:56:38 -0600
Subject: [PATCH] fix: handle empty YAML config files gracefully

When a YAML file (e.g. ~/.lando/config.yml) is completely empty,
yaml.load() returns undefined instead of an object. This causes a
TypeError when accessing properties like pluginDirs.

Default to an empty object when yaml.load() returns a falsy value
across all config loading paths.

Backport of lando/core#440
Fixes lando/core#439
---
 CHANGELOG.md               | 2 ++
 lib/cli.js                 | 2 +-
 lib/lando.js               | 2 +-
 utils/load-config-files.js | 2 +-
 4 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 269c404..0bb5845 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,7 @@
 ## {{ UNRELEASED_VERSION }} - [{{ UNRELEASED_DATE }}]({{ UNRELEASED_LINK }})
 
+* Fixed crash when `config.yml` is empty instead of containing `{}` [lando/core#439](https://github.com/lando/core/issues/439)
+
 ## v4.0.0-unstable.8 - [December 9, 2025](https://github.com/lando/core-next/releases/tag/v4.0.0-unstable.8)
 
 * Updated to prep for `bunification` part 2
diff --git a/lib/cli.js b/lib/cli.js
index 91af821..a37eccb 100644
--- a/lib/cli.js
+++ b/lib/cli.js
@@ -558,7 +558,7 @@ module.exports = class Cli {
     const Yaml = require(`../lib/yaml`);
     const yaml = new Yaml();
     const configFile = path.join(this.defaultConfig().userConfRoot, 'config.yml');
-    const config = (fs.existsSync(configFile)) ? yaml.load(configFile) : {};
+    const config = (fs.existsSync(configFile)) ? yaml.load(configFile) || {} : {};
     const file = yaml.dump(configFile, _.assign({}, config, data));
     return yaml.load(file);
   }
diff --git a/lib/lando.js b/lib/lando.js
index 496dadd..3403e5c 100644
--- a/lib/lando.js
+++ b/lib/lando.js
@@ -465,7 +465,7 @@ module.exports = class Lando {
     }
 
     // Load the config and augment so we can get an App
-    const config = lmerge({}, ..._.map(landoFiles, file => yaml.load(file)));
+    const config = lmerge({}, ..._.map(landoFiles, file => yaml.load(file) || {}));
     this.log.info('loading app %s from config files', config.name, landoFiles);
     // Return us some app!
     const App = require('./app');
diff --git a/utils/load-config-files.js b/utils/load-config-files.js
index 53f0ef6..923291d 100644
--- a/utils/load-config-files.js
+++ b/utils/load-config-files.js
@@ -52,7 +52,7 @@ module.exports = files => _(files)
   .filter(source => fs.existsSync(source) || fs.existsSync(source.file))
   // If the file is just a string lets map it to an object
   .map(source => {
-    return _.isString(source) ? {file: source, data: yaml.load(fs.readFileSync(source))} : source;
+    return _.isString(source) ? {file: source, data: yaml.load(fs.readFileSync(source)) || {}} : source;
   })
   // Add on the root directory for mapping purposes
   .map(source => _.merge({}, source, {root: path.dirname(source.file)}))