Add Psalm

Signed-off-by: Joas Schilling <coding@schilljs.com>

6 files changed, 1094 insertions, 5 deletions

diff --git a/.github/workflows/psalm.yml b/.github/workflows/psalm.yml
new file mode 100644
index 000000000..266433788
--- /dev/null
+++ b/.github/workflows/psalm.yml
@@ -0,0 +1,23 @@
+name: Static analysis
+on: [push]
+jobs:
+static-psalm-analysis:
+  runs-on: ubuntu-latest
+  strategy:
+    matrix:
+      ocp-version: [ 'dev-master' ]
+  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: composer run psalm
diff --git a/Makefile b/Makefile
index f73c01388..485fdb297 100644
--- a/Makefile
+++ b/Makefile
@@ -79,6 +79,7 @@ appstore:
 	--exclude=package-lock.json \
 	--exclude=.php_cs.dist \
 	--exclude=.php_cs.cache \
+	--exclude=psalm.xml \
 	--exclude=README.md \
 	--exclude=src \
 	--exclude=.stylelintignore \
diff --git a/composer.json b/composer.json
index 1c5cd09ae..f5efcfb37 100644
--- a/composer.json
+++ b/composer.json
@@ -2,9 +2,14 @@
 	"scripts": {
 		"cs:check": "php-cs-fixer fix --dry-run --diff",
 		"cs:fix": "php-cs-fixer fix",
-		"lint": "find . -name \\*.php -not -path './vendor/*' -not -path './build/*' -not -path './tests/integration/vendor/*' -print0 | xargs -0 -n1 php -l"
+		"lint": "find . -name \\*.php -not -path './vendor/*' -not -path './build/*' -not -path './tests/integration/vendor/*' -print0 | xargs -0 -n1 php -l",
+		"psalm": "psalm",
+		"psalm:fix": "psalm --alter --issues=InvalidReturnType,InvalidNullableReturnType,MissingParamType,InvalidFalsableReturnType"
 	},
+	"minimum-stability": "dev",
 	"require-dev": {
-		"nextcloud/coding-standard": "^0.3.0"
+		"nextcloud/coding-standard": "^0.3.0",
+		"vimeo/psalm": "^3.16",
+		"christophwurst/nextcloud": "dev-master"
 	}
 }
diff --git a/composer.lock b/composer.lock
index d35b983f3..2948f79d3 100644
--- a/composer.lock
+++ b/composer.lock
@@ -4,10 +4,265 @@
         "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#installing-dependencies",
         "This file is @generated automatically"
     ],
-    "content-hash": "89d50685180a9e527899b899920e7ac7",
+    "content-hash": "e279f7ddc109e01558906e07932f81b2",
     "packages": [],
     "packages-dev": [
         {
+            "name": "amphp/amp",
+            "version": "v2.5.0",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/amphp/amp.git",
+                "reference": "f220a51458bf4dd0dedebb171ac3457813c72bbc"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/amphp/amp/zipball/f220a51458bf4dd0dedebb171ac3457813c72bbc",
+                "reference": "f220a51458bf4dd0dedebb171ac3457813c72bbc",
+                "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"
+            ],
+            "funding": [
+                {
+                    "url": "https://github.com/amphp",
+                    "type": "github"
+                }
+            ],
+            "time": "2020-07-14T21:47:18+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"
+            ],
+            "time": "2020-06-29T18:35:05+00:00"
+        },
+        {
+            "name": "christophwurst/nextcloud",
+            "version": "dev-master",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/ChristophWurst/nextcloud_composer.git",
+                "reference": "40fb20d0ac2cc24a275937b19c7760821ce23b45"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/ChristophWurst/nextcloud_composer/zipball/40fb20d0ac2cc24a275937b19c7760821ce23b45",
+                "reference": "40fb20d0ac2cc24a275937b19c7760821ce23b45",
+                "shasum": ""
+            },
+            "require": {
+                "php": "^7.2"
+            },
+            "type": "library",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "21.0.0-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)",
+            "time": "2020-10-08T22:05:35+00:00"
+        },
+        {
+            "name": "composer/package-versions-deprecated",
+            "version": "1.11.99",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/composer/package-versions-deprecated.git",
+                "reference": "c8c9aa8a14cc3d3bec86d0a8c3fa52ea79936855"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/composer/package-versions-deprecated/zipball/c8c9aa8a14cc3d3bec86d0a8c3fa52ea79936855",
+                "reference": "c8c9aa8a14cc3d3bec86d0a8c3fa52ea79936855",
+                "shasum": ""
+            },
+            "require": {
+                "composer-plugin-api": "^1.1.0 || ^2.0",
+                "php": "^7 || ^8"
+            },
+            "replace": {
+                "ocramius/package-versions": "1.11.99"
+            },
+            "require-dev": {
+                "composer/composer": "^1.9.3 || ^2.0@dev",
+                "ext-zip": "^1.13",
+                "phpunit/phpunit": "^6.5 || ^7"
+            },
+            "type": "composer-plugin",
+            "extra": {
+                "class": "PackageVersions\\Installer",
+                "branch-alias": {
+                    "dev-master": "1.x-dev"
+                }
+            },
+            "autoload": {
+                "psr-4": {
+                    "PackageVersions\\": "src/PackageVersions"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Marco Pivetta",
+                    "email": "ocramius@gmail.com"
+                },
+                {
+                    "name": "Jordi Boggiano",
+                    "email": "j.boggiano@seld.be"
+                }
+            ],
+            "description": "Composer plugin that provides efficient querying for installed package versions (no runtime IO)",
+            "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": "2020-08-25T05:50:16+00:00"
+        },
+        {
             "name": "composer/semver",
             "version": "1.5.1",
             "source": {
@@ -119,6 +374,39 @@
             "time": "2020-03-01T12:26:26+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",
+            "time": "2019-12-04T15:06:13+00:00"
+        },
+        {
             "name": "doctrine/annotations",
             "version": "1.10.1",
             "source": {
@@ -250,6 +538,94 @@
             "time": "2019-10-30T14:39:59+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",
+            "time": "2020-03-11T15:21:41+00:00"
+        },
+        {
+            "name": "felixfbecker/language-server-protocol",
+            "version": "v1.4.0",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/felixfbecker/php-language-server-protocol.git",
+                "reference": "378801f6139bb74ac215d81cca1272af61df9a9f"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/felixfbecker/php-language-server-protocol/zipball/378801f6139bb74ac215d81cca1272af61df9a9f",
+                "reference": "378801f6139bb74ac215d81cca1272af61df9a9f",
+                "shasum": ""
+            },
+            "require": {
+                "php": "^7.0"
+            },
+            "require-dev": {
+                "phpstan/phpstan": "*",
+                "phpunit/phpunit": "^6.3",
+                "squizlabs/php_codesniffer": "^3.1"
+            },
+            "type": "library",
+            "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"
+            ],
+            "time": "2019-06-23T21:03:50+00:00"
+        },
+        {
             "name": "friendsofphp/php-cs-fixer",
             "version": "v2.16.2",
             "source": {
@@ -338,9 +714,61 @@
                 }
             ],
             "description": "A tool to automatically fix PHP code style",
+            "funding": [
+                {
+                    "url": "https://github.com/keradus",
+                    "type": "github"
+                }
+            ],
             "time": "2020-04-10T21:08:06+00:00"
         },
         {
+            "name": "netresearch/jsonmapper",
+            "version": "v2.1.0",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/cweiske/jsonmapper.git",
+                "reference": "e0f1e33a71587aca81be5cffbb9746510e1fe04e"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/cweiske/jsonmapper/zipball/e0f1e33a71587aca81be5cffbb9746510e1fe04e",
+                "reference": "e0f1e33a71587aca81be5cffbb9746510e1fe04e",
+                "shasum": ""
+            },
+            "require": {
+                "ext-json": "*",
+                "ext-pcre": "*",
+                "ext-reflection": "*",
+                "ext-spl": "*",
+                "php": ">=5.6"
+            },
+            "require-dev": {
+                "phpunit/phpunit": "~4.8.35 || ~5.7 || ~6.4 || ~7.0",
+                "squizlabs/php_codesniffer": "~3.5"
+            },
+            "type": "library",
+            "autoload": {
+                "psr-0": {
+                    "JsonMapper": "src/"
+                }
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "OSL-3.0"
+            ],
+            "authors": [
+                {
+                    "name": "Christian Weiske",
+                    "email": "cweiske@cweiske.de",
+                    "homepage": "http://github.com/cweiske/jsonmapper/",
+                    "role": "Developer"
+                }
+            ],
+            "description": "Map nested JSON structures onto PHP classes",
+            "time": "2020-04-16T18:48:43+00:00"
+        },
+        {
             "name": "nextcloud/coding-standard",
             "version": "v0.3.0",
             "source": {
@@ -378,6 +806,107 @@
             "time": "2020-04-10T14:57:18+00:00"
         },
         {
+            "name": "nikic/php-parser",
+            "version": "v4.10.2",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/nikic/PHP-Parser.git",
+                "reference": "658f1be311a230e0907f5dfe0213742aff0596de"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/nikic/PHP-Parser/zipball/658f1be311a230e0907f5dfe0213742aff0596de",
+                "reference": "658f1be311a230e0907f5dfe0213742aff0596de",
+                "shasum": ""
+            },
+            "require": {
+                "ext-tokenizer": "*",
+                "php": ">=7.0"
+            },
+            "require-dev": {
+