Add psalm for static code analysis

Signed-off-by: Benjamin Brahmer <info@b-brahmer.de>

4 files changed, 935 insertions, 2 deletions

diff --git a/.github/workflows/static-code-check.yml b/.github/workflows/static-code-check.yml
new file mode 100644
index 000000000..5ba49b170
--- /dev/null
+++ b/.github/workflows/static-code-check.yml
@@ -0,0 +1,25 @@
+name: Static analysis
+on:
+  pull_request
+jobs:
+  static-psalm-analysis:
+    runs-on: ubuntu-latest
+    continue-on-error: true
+    strategy:
+      matrix:
+        ocp-version: [ 'dev-master', 'v20.0.0' ]
+    name: Nextcloud ${{ matrix.ocp-version }}
+    steps:
+      - name: Checkout
+        uses: actions/checkout@master
+      - name: Set up php
+        uses: shivammathur/setup-php@master
+        with:
+          php-version: 7.4
+          coverage: none
+      - name: Install dependencies
+        run: composer i
+      - name: Install dependencies
+        run: composer require --dev christophwurst/nextcloud:${{ matrix.ocp-version }}
+      - name: Run coding standards check
+        run: ./vendor/bin/psalm
\ No newline at end of file
diff --git a/composer.json b/composer.json
index 9e9178ad8..bcfbca469 100644
--- a/composer.json
+++ b/composer.json
@@ -57,7 +57,9 @@
   "require-dev": {
     "phpunit/phpunit": "9.2.*",
     "squizlabs/php_codesniffer": "^3.5.6",
-    "phpstan/phpstan": "^0.12.43"
+    "phpstan/phpstan": "^0.12.43",
+    "christophwurst/nextcloud": "v20.0.0",
+    "vimeo/psalm": "^4.0"
   },
   "replace": {
     "guzzlehttp/guzzle": "*",
diff --git a/composer.lock b/composer.lock
index ffc9ea8d9..404f2549a 100644
--- a/composer.lock
+++ b/composer.lock
@@ -4,7 +4,7 @@
         "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#installing-dependencies",
         "This file is @generated automatically"
     ],
-    "content-hash": "985cf7807f611f683c25cac99ef81605",
+    "content-hash": "0de1efec082b85e2555555321960af29",
     "packages": [
         {
             "name": "andreskrey/readability.php",
@@ -479,6 +479,460 @@
     ],
     "packages-dev": [
         {
+            "name": "amphp/amp",
+            "version": "v2.5.1",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/amphp/amp.git",
+                "reference": "ecdc3c476b3ccff02f8e5d5bcc04f7ccfd18751c"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/amphp/amp/zipball/ecdc3c476b3ccff02f8e5d5bcc04f7ccfd18751c",
+                "reference": "ecdc3c476b3ccff02f8e5d5bcc04f7ccfd18751c",
+                "shasum": ""
+            },
+            "require": {
+                "php": ">=7"
+            },
+            "require-dev": {
+                "amphp/php-cs-fixer-config": "dev-master",
+                "amphp/phpunit-util": "^1",
+                "ext-json": "*",
+                "jetbrains/phpstorm-stubs": "^2019.3",
+                "phpunit/phpunit": "^6.0.9 | ^7",
+                "psalm/phar": "^3.11@dev",
+                "react/promise": "^2"
+            },
+            "type": "library",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "2.x-dev"
+                }
+            },
+            "autoload": {
+                "psr-4": {
+                    "Amp\\": "lib"
+                },
+                "files": [
+                    "lib/functions.php",
+                    "lib/Internal/functions.php"
+                ]
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Daniel Lowrey",
+                    "email": "rdlowrey@php.net"
+                },
+                {
+                    "name": "Aaron Piotrowski",
+                    "email": "aaron@trowski.com"
+                },
+                {
+                    "name": "Bob Weinand",
+                    "email": "bobwei9@hotmail.com"
+                },
+                {
+                    "name": "Niklas Keller",
+                    "email": "me@kelunik.com"
+                }
+            ],
+            "description": "A non-blocking concurrency framework for PHP applications.",
+            "homepage": "http://amphp.org/amp",
+            "keywords": [
+                "async",
+                "asynchronous",
+                "awaitable",
+                "concurrency",
+                "event",
+                "event-loop",
+                "future",
+                "non-blocking",
+                "promise"
+            ],
+            "support": {
+                "irc": "irc://irc.freenode.org/amphp",
+                "issues": "https://github.com/amphp/amp/issues",
+                "source": "https://github.com/amphp/amp/tree/v2.5.1"
+            },
+            "funding": [
+                {
+                    "url": "https://github.com/amphp",
+                    "type": "github"
+                }
+            ],
+            "time": "2020-11-03T16:23:45+00:00"
+        },
+        {
+            "name": "amphp/byte-stream",
+            "version": "v1.8.0",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/amphp/byte-stream.git",
+                "reference": "f0c20cf598a958ba2aa8c6e5a71c697d652c7088"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/amphp/byte-stream/zipball/f0c20cf598a958ba2aa8c6e5a71c697d652c7088",
+                "reference": "f0c20cf598a958ba2aa8c6e5a71c697d652c7088",
+                "shasum": ""
+            },
+            "require": {
+                "amphp/amp": "^2",
+                "php": ">=7.1"
+            },
+            "require-dev": {
+                "amphp/php-cs-fixer-config": "dev-master",
+                "amphp/phpunit-util": "^1.4",
+                "friendsofphp/php-cs-fixer": "^2.3",
+                "jetbrains/phpstorm-stubs": "^2019.3",
+                "phpunit/phpunit": "^6 || ^7 || ^8",
+                "psalm/phar": "^3.11.4"
+            },
+            "type": "library",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "1.x-dev"
+                }
+            },
+            "autoload": {
+                "psr-4": {
+                    "Amp\\ByteStream\\": "lib"
+                },
+                "files": [
+                    "lib/functions.php"
+                ]
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Aaron Piotrowski",
+                    "email": "aaron@trowski.com"
+                },
+                {
+                    "name": "Niklas Keller",
+                    "email": "me@kelunik.com"
+                }
+            ],
+            "description": "A stream abstraction to make working with non-blocking I/O simple.",
+            "homepage": "http://amphp.org/byte-stream",
+            "keywords": [
+                "amp",
+                "amphp",
+                "async",
+                "io",
+                "non-blocking",
+                "stream"
+            ],
+            "support": {
+                "irc": "irc://irc.freenode.org/amphp",
+                "issues": "https://github.com/amphp/byte-stream/issues",
+                "source": "https://github.com/amphp/byte-stream/tree/master"
+            },
+            "time": "2020-06-29T18:35:05+00:00"
+        },
+        {
+            "name": "christophwurst/nextcloud",
+            "version": "v20.0.0",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/ChristophWurst/nextcloud_composer.git",
+                "reference": "898b3b7feda1d8a761dffeaeda6fccace44eb649"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/ChristophWurst/nextcloud_composer/zipball/898b3b7feda1d8a761dffeaeda6fccace44eb649",
+                "reference": "898b3b7feda1d8a761dffeaeda6fccace44eb649",
+                "shasum": ""
+            },
+            "require": {
+                "php": "^7.2"
+            },
+            "type": "library",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "20.0.0-dev"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "AGPL-3.0-or-later"
+            ],
+            "authors": [
+                {
+                    "name": "Christoph Wurst",
+                    "email": "christoph@winzerhof-wurst.at"
+                }
+            ],
+            "description": "Composer package containing Nextcloud's public API (classes, interfaces)",
+            "support": {
+                "issues": "https://github.com/ChristophWurst/nextcloud_composer/issues",
+                "source": "https://github.com/ChristophWurst/nextcloud_composer/tree/v20.0.0"
+            },
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+        },
+        {
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+            "version": "1.11.99.1",
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+            "require": {
+                "composer-plugin-api": "^1.1.0 || ^2.0",
+                "php": "^7 || ^8"
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+            "replace": {
+                "ocramius/package-versions": "1.11.99"
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+            "require-dev": {
+                "composer/composer": "^1.9.3 || ^2.0@dev",
+                "ext-zip": "^1.13",
+                "phpunit/phpunit": "^6.5 || ^7"
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+            "extra": {
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+            "autoload": {
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+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
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+                    "email": "ocramius@gmail.com"
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+                    "name": "Jordi Boggiano",
+                    "email": "j.boggiano@seld.be"
+                }
+            ],
+            "description": "Composer plugin that provides efficient querying for installed package versions (no runtime IO)",
+            "support": {
+                "issues": "https://github.com/composer/package-versions-deprecated/issues",
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+            },
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+                    "type": "custom"
+                },
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+                    "type": "github"
+                },
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+                    "url": "https://tidelift.com/funding/github/packagist/composer/composer",
+                    "type": "tidelift"
+                }
+            ],
+            "time": "2020-11-11T10:22:58+00:00"
+        },
+        {
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+            "version": "3.2.4",
+            "source": {
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+                "reference": "a02fdf930a3c1c3ed3a49b5f63859c0c20e10464"
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+                "shasum": ""
+            },
+            "require": {
+                "php": "^5.3.2 || ^7.0 || ^8.0"
+            },
+            "require-dev": {
+                "phpstan/phpstan": "^0.12.54",
+                "symfony/phpunit-bridge": "^4.2 || ^5"
+            },
+            "type": "library",
+            "extra": {
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+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
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+                    "email": "naderman@naderman.de",
+                    "homepage": "http://www.naderman.de"
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+                    "email": "j.boggiano@seld.be",
+                    "homepage": "http://seld.be"
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+                    "email": "rob.bast@gmail.com",
+                    "homepage": "http://robbast.nl"
+                }
+            ],
+            "description": "Semver library that offers utilities, version constraint parsing and validation.",
+            "keywords": [
+                "semantic",
+                "semver",
+                "validation",
+                "versioning"
+            ],
+            "support": {
+                "irc": "irc://irc.freenode.org/composer",
+                "issues": "https://github.com/composer/semver/issues",
+                "source": "https://github.com/composer/semver/tree/3.2.4"
+            },
+            "funding": [
+                {
+                    "url": "https://packagist.com",
+                    "type": "custom"
+                },
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+                    "type": "github"
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+                    "type": "tidelift"
+                }
+            ],
+            "time": "2020-11-13T08:59:24+00:00"
+        },
+        {
+            "name": "composer/xdebug-handler",
+            "version": "1.4.5",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/composer/xdebug-handler.git",
+                "reference": "f28d44c286812c714741478d968104c5e604a1d4"
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+                "shasum": ""
+            },
+            "require": {
+                "php": "^5.3.2 || ^7.0 || ^8.0",
+                "psr/log": "^1.0"
+            },
+            "require-dev": {
+                "phpunit/phpunit": "^4.8.35 || ^5.7 || 6.5 - 8"
+            },
+            "type": "library",
+            "autoload": {
+                "psr-4": {
+                    "Composer\\XdebugHandler\\": "src"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "John Stevenson",
+                    "email": "john-stevenson@blueyonder.co.uk"
+                }
+            ],
+            "description": "Restarts a process without Xdebug.",
+            "keywords": [
+                "Xdebug",
+                "performance"
+            ],
+            "support": {
+                "irc": "irc://irc.freenode.org/composer",
+                "issues": "https://github.com/composer/xdebug-handler/issues",
+                "source": "https://github.com/composer/xdebug-handler/tree/1.4.5"
+            },
+            "funding": [
+                {
+                    "url": "https://packagist.com",
+                    "type": "custom"
+                },
+                {
+                    "url": "https://github.com/composer",
+                    "type": "github"
+                },
+                {
+                    "url": "https://tidelift.com/funding/github/packagist/composer/composer",
+                    "type": "tidelift"
+                }
+            ],
+            "time": "2020-11-13T08:04:11+00:00"
+        },
+        {
+            "name": "dnoegel/php-xdg-base-dir",
+            "version": "v0.1.1",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/dnoegel/php-xdg-base-dir.git",
+                "reference": "8f8a6e48c5ecb0f991c2fdcf5f154a47d85f9ffd"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/dnoegel/php-xdg-base-dir/zipball/8f8a6e48c5ecb0f991c2fdcf5f154a47d85f9ffd",
+                "reference": "8f8a6e48c5ecb0f991c2fdcf5f154a47d85f9ffd",
+                "shasum": ""
+            },
+            "require": {
+                "php": ">=5.3.2"
+            },
+            "require-dev": {
+                "phpunit/phpunit": "~7.0|~6.0|~5.0|~4.8.35"
+            },
+            "type": "library",
+            "autoload": {
+                "psr-4": {
+                    "XdgBaseDir\\": "src/"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "description": "implementation of xdg base directory specification for php",
+            "support": {
+                "issues": "https://github.com/dnoegel/php-xdg-base-dir/issues",
+                "source": "https://github.com/dnoegel/php-xdg-base-dir/tree/v0.1.1"
+            },
+            "time": "2019-12-04T15:06:13+00:00"
+        },
+        {
             "name": "doctrine/instantiator",
             "version": "1.4.0",
             "source": {
@@ -548,6 +1002,107 @@
             "time": "2020-11-10T18:47:58+00:00"
         },
         {
+            "name": "felixfbecker/advanced-json-rpc",
+            "version": "v3.1.1",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/felixfbecker/php-advanced-json-rpc.git",
+                "reference": "0ed363f8de17d284d479ec813c9ad3f6834b5c40"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/felixfbecker/php-advanced-json-rpc/zipball/0ed363f8de17d284d479ec813c9ad3f6834b5c40",
+                "reference": "0ed363f8de17d284d479ec813c9ad3f6834b5c40",
+                "shasum": ""
+            },
+            "require": {
+                "netresearch/jsonmapper": "^1.0 || ^2.0",
+                "php": ">=7.0",
+                "phpdocumentor/reflection-docblock": "^4.0.0 || ^5.0.0"
+            },
+            "require-dev": {
+                "phpunit/phpunit": "^6.0.0"
+            },
+            "type": "library",
+            "autoload": {
+                "psr-4": {
+                    "AdvancedJsonRpc\\": "lib/"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "ISC"
+            ],
+            "authors": [
+                {
+                    "name": "Felix Becker",
+                    "email": "felix.b@outlook.com"
+                }
+            ],
+            "description": "A more advanced JSONRPC implementation",
+            "support": {
+                "issues": "https://github.com/felixfbecker/php-advanced-json-rpc/issues",
+                "source": "https://github.com/felixfbecker/php-advanced-json-rpc/tree/master"
+            },
+            "time": "2020-03-11T15:21:41+00:00"
+        },
+        {
+            "name": "felixfbecker/language-server-protocol",
+            "version": "v1.5.0",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/felixfbecker/php-language-server-protocol.git",
+                "reference": "85e83cacd2ed573238678c6875f8f0d7ec699541"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/felixfbecker/php-language-server-protocol/zipball/85e83cacd2ed573238678c6875f8f0d7ec699541",
+                "reference": "85e83cacd2ed573238678c6875f8f0d7ec699541",
+                "shasum": ""
+            },
+            "require": {
+                "php": ">=7.1"
+            },
+            "require-dev": {
+                "phpstan/phpstan": "*",
+                "squizlabs/php_codesniffer": "^3.1",
+                "vimeo/psalm": "^4.0"
+            },
+            "type": "library",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "1.x-dev"
+                }
+            },
+            "autoload": {
+                "psr-4": {
+                    "LanguageServerProtocol\\": "src/"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "ISC"
+            ],
+            "authors": [
+                {
+                    "name": "Felix Becker",
+                    "email": "felix.b@outlook.com"
+                }
+            ],
+            "description": "PHP classes for the Language Server Protocol",
+            "keywords": [
+                "language",
+                "microsoft",
+                "php",
+                "server"
+            ],
+            "support": {
+                "issues": "https://github.com/felixfbecker/php-language-server-protocol/issues",
+                "source": "https://github.com/felixfbecker/php-language-server-protocol/tree/v1.5.0"
+            },
+            "time": "2020-10-23T13:55:30+00:00"
+        },
+        {
             "name": "myclabs/deep-copy",
             "version": "1.10.2",
             "source": {
@@ -606,6 +1161,166 @@
             "time": "2020-11-13T09:40:50+00:00"
         },
         {
+            "name": "netresearch/jsonmapper",
+            "version": "v2.1.0",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/cweiske/jsonmapper.git",
+                "reference": "e0f1e33a71587aca81be5cffbb9746510e1fe04e"
+            },
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+            "notification-url": "https://packagist.org/downloads/",
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+            "authors": [
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+                    "name": "Christian Weiske",
+                    "email": "cweiske@cweiske.de",
+                    "homepage": "http://github.com/cweiske/jsonmapper/",
+                    "role": "Developer"
+                }
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+            "description": "Map nested JSON structures onto PHP classes",
+            "support": {
+                "email": "cweiske@cweiske.de",
+                "issues": "https://github.com/cweiske/jsonmapper/issues",
+                "source": "https://github.com/cweiske/jsonmapper/tree/master"
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