From 7c5e5e3ede952486010defdb1a938202788847b6 Mon Sep 17 00:00:00 2001
From: Arnout Boks <arnoutboks@gmail.com>
Date: Sat, 19 Oct 2019 21:46:29 +0200
Subject: [PATCH] Add option to disable the lock file

When the `lock` option is set to false, composer will not write a
`composer.lock` file to disk. This signals that the package is meant
to be developed with unlocked and always updated dependencies. At the
moment, both `install` and `update` are allowed to install the
dependencies for such a package. If #6822 is implemented, only `update`
should be used for packages without a lockfile.

https://github.com/composer/composer/issues/8354
---
 doc/06-config.md                       | 5 +++++
 res/composer-schema.json               | 4 ++++
 src/Composer/Command/ConfigCommand.php | 1 +
 src/Composer/Config.php                | 3 +++
 src/Composer/Installer.php             | 4 +++-
 5 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/doc/06-config.md b/doc/06-config.md
index f3afc4eb1..6ffbea411 100644
--- a/doc/06-config.md
+++ b/doc/06-config.md
@@ -296,4 +296,9 @@ Example:
 Defaults to `true`. If set to `false`, Composer will not create `.htaccess` files
 in the composer home, cache, and data directories.
 
+## lock
+
+Defaults to `true`. If set to `false`, Composer will not create a `composer.lock` 
+file.
+
 &larr; [Repositories](05-repositories.md)  |  [Community](07-community.md) &rarr;
diff --git a/res/composer-schema.json b/res/composer-schema.json
index cb3594f7b..a45574f77 100644
--- a/res/composer-schema.json
+++ b/res/composer-schema.json
@@ -290,6 +290,10 @@
                 "sort-packages": {
                     "type": "boolean",
                     "description": "Defaults to false. If set to true, Composer will sort packages when adding/updating a new dependency."
+                },
+                "lock": {
+                    "type": "boolean",
+                    "description": "Defaults to true. If set to false, Composer will not create a composer.lock file."
                 }
             }
         },
diff --git a/src/Composer/Command/ConfigCommand.php b/src/Composer/Command/ConfigCommand.php
index 71ec9d816..24e2bd3c3 100644
--- a/src/Composer/Command/ConfigCommand.php
+++ b/src/Composer/Command/ConfigCommand.php
@@ -412,6 +412,7 @@ EOT
             ),
             'github-expose-hostname' => array($booleanValidator, $booleanNormalizer),
             'htaccess-protect' => array($booleanValidator, $booleanNormalizer),
+            'lock' => array($booleanValidator, $booleanNormalizer),
         );
         $multiConfigValues = array(
             'github-protocols' => array(
diff --git a/src/Composer/Config.php b/src/Composer/Config.php
index 7abca7dfa..1050096b1 100644
--- a/src/Composer/Config.php
+++ b/src/Composer/Config.php
@@ -63,6 +63,7 @@ class Config
         'archive-dir' => '.',
         'htaccess-protect' => true,
         'use-github-api' => true,
+        'lock' => true,
         // valid keys without defaults (auth config stuff):
         // bitbucket-oauth
         // github-oauth
@@ -329,6 +330,8 @@ class Config
                 return $this->config[$key] !== 'false' && (bool) $this->config[$key];
             case 'use-github-api':
                 return $this->config[$key] !== 'false' && (bool) $this->config[$key];
+            case 'lock':
+                return $this->config[$key] !== 'false' && (bool) $this->config[$key];
             default:
                 if (!isset($this->config[$key])) {
                     return null;
diff --git a/src/Composer/Installer.php b/src/Composer/Installer.php
index 11edcbe72..d688a4f1f 100644
--- a/src/Composer/Installer.php
+++ b/src/Composer/Installer.php
@@ -118,7 +118,7 @@ class Installer
     protected $preferStable = false;
     protected $preferLowest = false;
     protected $skipSuggest = false;
-    protected $writeLock = true;
+    protected $writeLock;
     protected $executeOperations = true;
 
     /**
@@ -164,6 +164,8 @@ class Installer
         $this->installationManager = $installationManager;
         $this->eventDispatcher = $eventDispatcher;
         $this->autoloadGenerator = $autoloadGenerator;
+
+        $this->writeLock = $config->get('lock');
     }
 
     /**