From acdb11e6792fea8a892a5ad7dcb24484df7f8296 Mon Sep 17 00:00:00 2001
From: Bruce Weirdan <weirdan@gmail.com>
Date: Fri, 21 Jul 2023 02:06:08 +0200
Subject: [PATCH 01/11] Use instance methods instead of static

---
 .../LanguageServer/LanguageServer.php         |  4 ++--
 .../LanguageServer/Server/TextDocument.php    | 22 +++++++++----------
 .../LanguageServer/Server/Workspace.php       |  6 ++---
 3 files changed, 16 insertions(+), 16 deletions(-)

diff --git a/src/Psalm/Internal/LanguageServer/LanguageServer.php b/src/Psalm/Internal/LanguageServer/LanguageServer.php
index 54009b9cc5a..07990378bd2 100644
--- a/src/Psalm/Internal/LanguageServer/LanguageServer.php
+++ b/src/Psalm/Internal/LanguageServer/LanguageServer.php
@@ -951,7 +951,7 @@ private function clientStatus(string $status, ?string $additional_info = null):
      *
      * @psalm-pure
      */
-    public static function pathToUri(string $filepath): string
+    public function pathToUri(string $filepath): string
     {
         $filepath = trim(str_replace('\\', '/', $filepath), '/');
         $parts = explode('/', $filepath);
@@ -970,7 +970,7 @@ public static function pathToUri(string $filepath): string
     /**
      * Transforms URI into file path
      */
-    public static function uriToPath(string $uri): string
+    public function uriToPath(string $uri): string
     {
         $fragments = parse_url($uri);
         if ($fragments === false
diff --git a/src/Psalm/Internal/LanguageServer/Server/TextDocument.php b/src/Psalm/Internal/LanguageServer/Server/TextDocument.php
index 1ea170a86f0..b24862e7460 100644
--- a/src/Psalm/Internal/LanguageServer/Server/TextDocument.php
+++ b/src/Psalm/Internal/LanguageServer/Server/TextDocument.php
@@ -74,7 +74,7 @@ public function didOpen(TextDocumentItem $textDocument): void
             ['version' => $textDocument->version, 'uri' => $textDocument->uri],
         );
 
-        $file_path = LanguageServer::uriToPath($textDocument->uri);
+        $file_path = $this->server->uriToPath($textDocument->uri);
 
         $this->codebase->removeTemporaryFileChanges($file_path);
         $this->codebase->file_provider->openFile($file_path);
@@ -97,7 +97,7 @@ public function didSave(TextDocumentIdentifier $textDocument, ?string $text = nu
             ['uri' => (array) $textDocument],
         );
 
-        $file_path = LanguageServer::uriToPath($textDocument->uri);
+        $file_path = $this->server->uriToPath($textDocument->uri);
 
         // reopen file
         $this->codebase->removeTemporaryFileChanges($file_path);
@@ -119,7 +119,7 @@ public function didChange(VersionedTextDocumentIdentifier $textDocument, array $
             ['version' => $textDocument->version, 'uri' => $textDocument->uri],
         );
 
-        $file_path = LanguageServer::uriToPath($textDocument->uri);
+        $file_path = $this->server->uriToPath($textDocument->uri);
 
         if (count($contentChanges) === 1 && isset($contentChanges[0]) && $contentChanges[0]->range === null) {
             $new_content = $contentChanges[0]->text;
@@ -154,7 +154,7 @@ public function didClose(TextDocumentIdentifier $textDocument): void
             ['uri' => $textDocument->uri],
         );
 
-        $file_path = LanguageServer::uriToPath($textDocument->uri);
+        $file_path = $this->server->uriToPath($textDocument->uri);
 
         $this->codebase->file_provider->closeFile($file_path);
         $this->server->client->textDocument->publishDiagnostics($textDocument->uri, []);
@@ -178,7 +178,7 @@ public function definition(TextDocumentIdentifier $textDocument, Position $posit
             'textDocument/definition',
         );
 
-        $file_path = LanguageServer::uriToPath($textDocument->uri);
+        $file_path = $this->server->uriToPath($textDocument->uri);
 
         //This currently doesnt work right with out of project files
         if (!$this->codebase->config->isInProjectDirs($file_path)) {
@@ -205,7 +205,7 @@ public function definition(TextDocumentIdentifier $textDocument, Position $posit
 
         return new Success(
             new Location(
-                LanguageServer::pathToUri($code_location->file_path),
+                $this->server->pathToUri($code_location->file_path),
                 new Range(
                     new Position($code_location->getLineNumber() - 1, $code_location->getColumn() - 1),
                     new Position($code_location->getEndLineNumber() - 1, $code_location->getEndColumn() - 1),
@@ -232,7 +232,7 @@ public function hover(TextDocumentIdentifier $textDocument, Position $position):
             'textDocument/hover',
         );
 
-        $file_path = LanguageServer::uriToPath($textDocument->uri);
+        $file_path = $this->server->uriToPath($textDocument->uri);
 
         //This currently doesnt work right with out of project files
         if (!$this->codebase->config->isInProjectDirs($file_path)) {
@@ -288,7 +288,7 @@ public function completion(TextDocumentIdentifier $textDocument, Position $posit
             'textDocument/completion',
         );
 
-        $file_path = LanguageServer::uriToPath($textDocument->uri);
+        $file_path = $this->server->uriToPath($textDocument->uri);
 
         //This currently doesnt work right with out of project files
         if (!$this->codebase->config->isInProjectDirs($file_path)) {
@@ -356,7 +356,7 @@ public function signatureHelp(TextDocumentIdentifier $textDocument, Position $po
             'textDocument/signatureHelp',
         );
 
-        $file_path = LanguageServer::uriToPath($textDocument->uri);
+        $file_path = $this->server->uriToPath($textDocument->uri);
 
         //This currently doesnt work right with out of project files
         if (!$this->codebase->config->isInProjectDirs($file_path)) {
@@ -411,7 +411,7 @@ public function codeAction(TextDocumentIdentifier $textDocument, Range $range, C
             'textDocument/codeAction',
         );
 
-        $file_path = LanguageServer::uriToPath($textDocument->uri);
+        $file_path = $this->server->uriToPath($textDocument->uri);
 
         //Don't report code actions for files we arent watching
         if (!$this->codebase->config->isInProjectDirs($file_path)) {
@@ -427,7 +427,7 @@ public function codeAction(TextDocumentIdentifier $textDocument, Range $range, C
             /** @var array{type: string, snippet: string, line_from: int, line_to: int} */
             $data = (array)$diagnostic->data;
 
-            //$file_path = LanguageServer::uriToPath($textDocument->uri);
+            //$file_path = $this->server->uriToPath($textDocument->uri);
             //$contents = $this->codebase->file_provider->getContents($file_path);
 
             $snippetRange = new Range(
diff --git a/src/Psalm/Internal/LanguageServer/Server/Workspace.php b/src/Psalm/Internal/LanguageServer/Server/Workspace.php
index af49619c356..113a8f17974 100644
--- a/src/Psalm/Internal/LanguageServer/Server/Workspace.php
+++ b/src/Psalm/Internal/LanguageServer/Server/Workspace.php
@@ -63,7 +63,7 @@ public function didChangeWatchedFiles(array $changes): void
         $realFiles = array_filter(
             array_map(function (FileEvent $change) {
                 try {
-                    return LanguageServer::uriToPath($change->uri);
+                    return $this->server->uriToPath($change->uri);
                 } catch (InvalidArgumentException $e) {
                     return null;
                 }
@@ -79,7 +79,7 @@ public function didChangeWatchedFiles(array $changes): void
         }
 
         foreach ($changes as $change) {
-            $file_path = LanguageServer::uriToPath($change->uri);
+            $file_path = $this->server->uriToPath($change->uri);
 
             if ($composerLockFile === $file_path) {
                 continue;
@@ -140,7 +140,7 @@ public function executeCommand(string $command, $arguments): Promise
             case 'psalm.analyze.uri':
                 /** @var array{uri: string} */
                 $arguments = (array) $arguments;
-                $file = LanguageServer::uriToPath($arguments['uri']);
+                $file = $this->server->uriToPath($arguments['uri']);
                 $this->codebase->reloadFiles(
                     $this->project_analyzer,
                     [$file],

From c44b9f5c5e5739f1a59a3b7f4334645f9c1fd66c Mon Sep 17 00:00:00 2001
From: Bruce Weirdan <weirdan@gmail.com>
Date: Fri, 21 Jul 2023 18:22:29 +0200
Subject: [PATCH 02/11] Map LSP paths

---
 .../LanguageServer/LanguageServer.php         | 57 ++++++++++++++-----
 1 file changed, 44 insertions(+), 13 deletions(-)

diff --git a/src/Psalm/Internal/LanguageServer/LanguageServer.php b/src/Psalm/Internal/LanguageServer/LanguageServer.php
index 07990378bd2..c23e0ef4d6b 100644
--- a/src/Psalm/Internal/LanguageServer/LanguageServer.php
+++ b/src/Psalm/Internal/LanguageServer/LanguageServer.php
@@ -142,6 +142,8 @@ class LanguageServer extends Dispatcher
      */
     protected JsonMapper $mapper;
 
+    protected ?string $clientRootPath = null;
+
     public function __construct(
         ProtocolReader $reader,
         ProtocolWriter $writer,
@@ -394,6 +396,11 @@ public function initialize(
         $this->clientInfo = $clientInfo;
         $this->clientCapabilities = $capabilities;
         $this->trace = $trace;
+
+        if ($rootUri !== null) {
+            $this->clientRootPath = $this->getPathPart($rootUri);
+        }
+
         return call(
             /** @return Generator<int, true, mixed, InitializeResult> */
             function () {
@@ -948,12 +955,22 @@ private function clientStatus(string $status, ?string $additional_info = null):
 
     /**
      * Transforms an absolute file path into a URI as used by the language server protocol.
-     *
-     * @psalm-pure
      */
     public function pathToUri(string $filepath): string
     {
-        $filepath = trim(str_replace('\\', '/', $filepath), '/');
+        $filepath = str_replace('\\', '/', $filepath);
+
+        if ($this->clientRootPath !== null) {
+            $oldpath = $filepath;
+            $filepath = str_replace(
+                rtrim($this->codebase->config->base_dir, '/') . '/',
+                rtrim($this->clientRootPath, '/') . '/',
+                $filepath
+            );
+            $this->logDebug('Translated path to URI', ['from' => $oldpath, 'to' => $filepath]);
+        }
+
+        $filepath = trim($filepath, '/');
         $parts = explode('/', $filepath);
         // Don't %-encode the colon after a Windows drive letter
         $first = array_shift($parts);
@@ -972,16 +989,7 @@ public function pathToUri(string $filepath): string
      */
     public function uriToPath(string $uri): string
     {
-        $fragments = parse_url($uri);
-        if ($fragments === false
-            || !isset($fragments['scheme'])
-            || $fragments['scheme'] !== 'file'
-            || !isset($fragments['path'])
-        ) {
-            throw new InvalidArgumentException("Not a valid file URI: $uri");
-        }
-
-        $filepath = urldecode($fragments['path']);
+        $filepath = urldecode($this->getPathPart($uri));
 
         if (strpos($filepath, ':') !== false) {
             if ($filepath[0] === '/') {
@@ -990,6 +998,16 @@ public function uriToPath(string $uri): string
             $filepath = str_replace('/', '\\', $filepath);
         }
 
+        if ($this->clientRootPath !== null) {
+            $oldpath = $filepath;
+            $filepath = str_replace(
+                rtrim($this->clientRootPath, '/') . '/',
+                rtrim($this->codebase->config->base_dir, '/') . '/',
+                $filepath
+            );
+            $this->logDebug('Translated URI to path', ['from' => $oldpath, 'to' => $filepath]);
+        }
+
         $realpath = realpath($filepath);
         if ($realpath !== false) {
             return $realpath;
@@ -997,4 +1015,17 @@ public function uriToPath(string $uri): string
 
         return $filepath;
     }
+
+    private function getPathPart(string $uri): string
+    {
+        $fragments = parse_url($uri);
+        if ($fragments === false
+            || !isset($fragments['scheme'])
+            || $fragments['scheme'] !== 'file'
+            || !isset($fragments['path'])
+        ) {
+            throw new InvalidArgumentException("Not a valid file URI: $uri");
+        }
+        return $fragments['path'];
+    }
 }

From f634a0047a631ffe59656457fad04f94db833f21 Mon Sep 17 00:00:00 2001
From: Bruce Weirdan <weirdan@gmail.com>
Date: Fri, 21 Jul 2023 18:31:47 +0200
Subject: [PATCH 03/11] CS fix

---
 src/Psalm/Internal/LanguageServer/LanguageServer.php | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/Psalm/Internal/LanguageServer/LanguageServer.php b/src/Psalm/Internal/LanguageServer/LanguageServer.php
index c23e0ef4d6b..5ea1ea8ef6b 100644
--- a/src/Psalm/Internal/LanguageServer/LanguageServer.php
+++ b/src/Psalm/Internal/LanguageServer/LanguageServer.php
@@ -80,6 +80,7 @@
 use function parse_url;
 use function rawurlencode;
 use function realpath;
+use function rtrim;
 use function str_replace;
 use function stream_set_blocking;
 use function stream_socket_accept;
@@ -965,7 +966,7 @@ public function pathToUri(string $filepath): string
             $filepath = str_replace(
                 rtrim($this->codebase->config->base_dir, '/') . '/',
                 rtrim($this->clientRootPath, '/') . '/',
-                $filepath
+                $filepath,
             );
             $this->logDebug('Translated path to URI', ['from' => $oldpath, 'to' => $filepath]);
         }
@@ -1003,7 +1004,7 @@ public function uriToPath(string $uri): string
             $filepath = str_replace(
                 rtrim($this->clientRootPath, '/') . '/',
                 rtrim($this->codebase->config->base_dir, '/') . '/',
-                $filepath
+                $filepath,
             );
             $this->logDebug('Translated URI to path', ['from' => $oldpath, 'to' => $filepath]);
         }

From a68c4804f4b8ef14fcaa426712f8a95a59afb414 Mon Sep 17 00:00:00 2001
From: Bruce Weirdan <weirdan@gmail.com>
Date: Sun, 23 Jul 2023 00:04:25 +0200
Subject: [PATCH 04/11] Add path mapper

---
 .../Internal/LanguageServer/PathMapper.php    | 57 ++++++++++++++
 tests/LanguageServer/PathMapperTest.php       | 75 +++++++++++++++++++
 2 files changed, 132 insertions(+)
 create mode 100644 src/Psalm/Internal/LanguageServer/PathMapper.php
 create mode 100644 tests/LanguageServer/PathMapperTest.php

diff --git a/src/Psalm/Internal/LanguageServer/PathMapper.php b/src/Psalm/Internal/LanguageServer/PathMapper.php
new file mode 100644
index 00000000000..8d9a09bdb89
--- /dev/null
+++ b/src/Psalm/Internal/LanguageServer/PathMapper.php
@@ -0,0 +1,57 @@
+<?php
+
+namespace Psalm\Internal\LanguageServer;
+
+/** @internal */
+final class PathMapper
+{
+    private string $serverRoot;
+    private ?string $clientRoot;
+
+    public function __construct(string $serverRoot, ?string $clientRoot = null)
+    {
+        $this->serverRoot = $this->sanitizeFolderPath($serverRoot);
+        $this->clientRoot = $this->sanitizeFolderPath($clientRoot);
+    }
+
+    public function configureClientRoot(string $clientRoot): void
+    {
+        // ignore if preconfigured
+        if ($this->clientRoot === null) {
+            $this->clientRoot = $this->sanitizeFolderPath($clientRoot);
+        }
+    }
+
+    public function mapClientToServer(string $clientPath): string
+    {
+        if ($this->clientRoot === null) {
+            return $clientPath;
+        }
+
+        if (substr($clientPath, 0, strlen($this->clientRoot)) === $this->clientRoot) {
+            return $this->serverRoot . substr($clientPath, strlen($this->clientRoot));
+        }
+
+        return $clientPath;
+    }
+
+    public function mapServerToClient(string $serverPath): string
+    {
+        if ($this->clientRoot === null) {
+            return $serverPath;
+        }
+        if (substr($serverPath, 0, strlen($this->serverRoot)) === $this->serverRoot) {
+            return $this->clientRoot . substr($serverPath, strlen($this->serverRoot));
+        }
+        return $serverPath;
+    }
+
+    /** @return ($path is null ? null : string) */
+    private function sanitizeFolderPath(?string $path): ?string
+    {
+        if ($path === null) {
+            return $path;
+        }
+        return rtrim($path, '/');
+    }
+}
diff --git a/tests/LanguageServer/PathMapperTest.php b/tests/LanguageServer/PathMapperTest.php
new file mode 100644
index 00000000000..c6a45a1b759
--- /dev/null
+++ b/tests/LanguageServer/PathMapperTest.php
@@ -0,0 +1,75 @@
+<?php
+
+namespace Psalm\Tests\LanguageServer;
+
+use PHPUnit\Framework\TestCase;
+use Psalm\Internal\LanguageServer\PathMapper;
+
+final class PathMapperTest extends TestCase
+{
+    public function testUsesUpdatedClientRoot(): void
+    {
+        $mapper = new PathMapper('/var/www');
+        $mapper->configureClientRoot('/home/user/src/project');
+        $this->assertSame(
+            '/home/user/src/project/filename.php',
+            $mapper->mapServerToClient('/var/www/filename.php')
+        );
+    }
+
+    public function testIgnoresClientRootIfItWasPreconfigures(): void
+    {
+        $mapper = new PathMapper('/var/www', '/home/user/src/project');
+        // this will be ignored
+        $mapper->configureClientRoot('/home/anotheruser/Projects/project');
+
+        $this->assertSame(
+            '/home/user/src/project/filename.php',
+            $mapper->mapServerToClient('/var/www/filename.php')
+        );
+    }
+
+    /**
+     * @dataProvider mappingProvider
+     */
+    public function testMapsClientToServer(
+        string $serverRoot,
+        ?string $clientRootPreconfigured,
+        string $clientRootProvidedLater,
+        string $clientPath,
+        string $serverPath
+    ): void {
+        $mapper = new PathMapper($serverRoot, $clientRootPreconfigured);
+        $mapper->configureClientRoot($clientRootProvidedLater);
+        $this->assertSame(
+            $serverPath,
+            $mapper->mapClientToServer($clientPath)
+        );
+    }
+
+    /** @dataProvider mappingProvider */
+    public function testMapsServerToClient(
+        string $serverRoot,
+        ?string $clientRootPreconfigured,
+        string $clientRootProvidedLater,
+        string $clientPath,
+        string $serverPath
+    ): void {
+        $mapper = new PathMapper($serverRoot, $clientRootPreconfigured);
+        $mapper->configureClientRoot($clientRootProvidedLater);
+        $this->assertSame(
+            $clientPath,
+            $mapper->mapServerToClient($serverPath)
+        );
+    }
+
+    /** @return iterable<int, array{string, string|null, string, string, string}> */
+    public static function mappingProvider(): iterable
+    {
+        yield ["/var/a",  null,             "/user/project", "/user/project/filename.php", "/var/a/filename.php"];
+        yield ["/var/a",  "/user/project",  "/whatever",     "/user/project/filename.php", "/var/a/filename.php"];
+        yield ["/var/a/", "/user/project",  "/whatever",     "/user/project/filename.php", "/var/a/filename.php"];
+        yield ["/var/a",  "/user/project/", "/whatever",     "/user/project/filename.php", "/var/a/filename.php"];
+        yield ["/var/a/", "/user/project/", "/whatever",     "/user/project/filename.php", "/var/a/filename.php"];
+    }
+}

From 389aa7965f12d8709f65f00dffe2c7b9cbd153a3 Mon Sep 17 00:00:00 2001
From: Bruce Weirdan <weirdan@gmail.com>
Date: Sun, 23 Jul 2023 00:56:06 +0200
Subject: [PATCH 05/11] Use PathMapper to map paths

---
 .../LanguageServer/LanguageServer.php         | 29 +++++++------------
 1 file changed, 10 insertions(+), 19 deletions(-)

diff --git a/src/Psalm/Internal/LanguageServer/LanguageServer.php b/src/Psalm/Internal/LanguageServer/LanguageServer.php
index 5ea1ea8ef6b..3ea4b50465f 100644
--- a/src/Psalm/Internal/LanguageServer/LanguageServer.php
+++ b/src/Psalm/Internal/LanguageServer/LanguageServer.php
@@ -145,6 +145,8 @@ class LanguageServer extends Dispatcher
 
     protected ?string $clientRootPath = null;
 
+    protected PathMapper $path_mapper;
+
     public function __construct(
         ProtocolReader $reader,
         ProtocolWriter $writer,
@@ -243,6 +245,8 @@ function (): void {
 
         $this->client = new LanguageClient($reader, $writer, $this, $clientConfiguration);
 
+        $this->path_mapper = new PathMapper($codebase->config->base_dir, null);
+
         $this->logInfo("Psalm Language Server ".PSALM_VERSION." has started.");
     }
 
@@ -398,8 +402,9 @@ public function initialize(
         $this->clientCapabilities = $capabilities;
         $this->trace = $trace;
 
+
         if ($rootUri !== null) {
-            $this->clientRootPath = $this->getPathPart($rootUri);
+            $this->path_mapper->configureClientRoot($this->getPathPart($rootUri));
         }
 
         return call(
@@ -961,15 +966,8 @@ public function pathToUri(string $filepath): string
     {
         $filepath = str_replace('\\', '/', $filepath);
 
-        if ($this->clientRootPath !== null) {
-            $oldpath = $filepath;
-            $filepath = str_replace(
-                rtrim($this->codebase->config->base_dir, '/') . '/',
-                rtrim($this->clientRootPath, '/') . '/',
-                $filepath,
-            );
-            $this->logDebug('Translated path to URI', ['from' => $oldpath, 'to' => $filepath]);
-        }
+        $filepath = $this->path_mapper->mapServerToClient($oldpath = $filepath);
+        $this->logDebug('Translated path to URI', ['from' => $oldpath, 'to' => $filepath]);
 
         $filepath = trim($filepath, '/');
         $parts = explode('/', $filepath);
@@ -999,15 +997,8 @@ public function uriToPath(string $uri): string
             $filepath = str_replace('/', '\\', $filepath);
         }
 
-        if ($this->clientRootPath !== null) {
-            $oldpath = $filepath;
-            $filepath = str_replace(
-                rtrim($this->clientRootPath, '/') . '/',
-                rtrim($this->codebase->config->base_dir, '/') . '/',
-                $filepath,
-            );
-            $this->logDebug('Translated URI to path', ['from' => $oldpath, 'to' => $filepath]);
-        }
+        $filepath = $this->path_mapper->mapClientToServer($oldpath = $filepath);
+        $this->logDebug('Translated URI to path', ['from' => $oldpath, 'to' => $filepath]);
 
         $realpath = realpath($filepath);
         if ($realpath !== false) {

From 6b9d9805b12f11bf02f0a0c32324c667bed9d1e2 Mon Sep 17 00:00:00 2001
From: Bruce Weirdan <weirdan@gmail.com>
Date: Sun, 23 Jul 2023 01:13:37 +0200
Subject: [PATCH 06/11] Account for `-r` option

---
 src/Psalm/Internal/Cli/LanguageServer.php            |  4 +++-
 src/Psalm/Internal/LanguageServer/LanguageServer.php | 10 +++++++---
 tests/LanguageServer/DiagnosticTest.php              |  1 +
 3 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/src/Psalm/Internal/Cli/LanguageServer.php b/src/Psalm/Internal/Cli/LanguageServer.php
index 429144b6808..cc52be7a7d4 100644
--- a/src/Psalm/Internal/Cli/LanguageServer.php
+++ b/src/Psalm/Internal/Cli/LanguageServer.php
@@ -254,6 +254,8 @@ static function (string $arg) use ($valid_long_options): void {
             $current_dir = $root_path . DIRECTORY_SEPARATOR;
         }
 
+        $server_start_dir = $current_dir;
+
         $vendor_dir = CliUtils::getVendorDir($current_dir);
 
         $include_collector = new IncludeCollector();
@@ -394,6 +396,6 @@ static function (string $arg) use ($valid_long_options): void {
         $clientConfiguration->TCPServerAddress = $options['tcp'] ?? null;
         $clientConfiguration->TCPServerMode = isset($options['tcp-server']);
 
-        LanguageServerLanguageServer::run($config, $clientConfiguration, $current_dir, $inMemory);
+        LanguageServerLanguageServer::run($config, $clientConfiguration, $current_dir, $server_start_dir, $inMemory);
     }
 }
diff --git a/src/Psalm/Internal/LanguageServer/LanguageServer.php b/src/Psalm/Internal/LanguageServer/LanguageServer.php
index 3ea4b50465f..4ffe03af380 100644
--- a/src/Psalm/Internal/LanguageServer/LanguageServer.php
+++ b/src/Psalm/Internal/LanguageServer/LanguageServer.php
@@ -80,7 +80,6 @@
 use function parse_url;
 use function rawurlencode;
 use function realpath;
-use function rtrim;
 use function str_replace;
 use function stream_set_blocking;
 use function stream_socket_accept;
@@ -153,7 +152,8 @@ public function __construct(
         ProjectAnalyzer $project_analyzer,
         Codebase $codebase,
         ClientConfiguration $clientConfiguration,
-        Progress $progress
+        Progress $progress,
+        string $server_start_dir
     ) {
         parent::__construct($this, '/');
 
@@ -245,7 +245,7 @@ function (): void {
 
         $this->client = new LanguageClient($reader, $writer, $this, $clientConfiguration);
 
-        $this->path_mapper = new PathMapper($codebase->config->base_dir, null);
+        $this->path_mapper = new PathMapper($server_start_dir, null);
 
         $this->logInfo("Psalm Language Server ".PSALM_VERSION." has started.");
     }
@@ -257,6 +257,7 @@ public static function run(
         Config $config,
         ClientConfiguration $clientConfiguration,
         string $base_dir,
+        string $server_start_dir,
         bool $inMemory = false
     ): void {
         $progress = new Progress();
@@ -329,6 +330,7 @@ public static function run(
                 $codebase,
                 $clientConfiguration,
                 $progress,
+                $server_start_dir,
             );
             Loop::run();
         } elseif ($clientConfiguration->TCPServerMode && $clientConfiguration->TCPServerAddress) {
@@ -352,6 +354,7 @@ public static function run(
                     $codebase,
                     $clientConfiguration,
                     $progress,
+                    $server_start_dir,
                 );
                 Loop::run();
             }
@@ -365,6 +368,7 @@ public static function run(
                 $codebase,
                 $clientConfiguration,
                 $progress,
+                $server_start_dir,
             );
             Loop::run();
         }
diff --git a/tests/LanguageServer/DiagnosticTest.php b/tests/LanguageServer/DiagnosticTest.php
index 690c008ea95..ea480138c20 100644
--- a/tests/LanguageServer/DiagnosticTest.php
+++ b/tests/LanguageServer/DiagnosticTest.php
@@ -85,6 +85,7 @@ public function testSnippetSupportDisabled(): void
             $this->codebase,
             $clientConfiguration,
             new Progress,
+            getcwd(),
         );
 
         $write->on('message', function (Message $message) use ($deferred, $server): void {

From 8a51aaedd489953026f4cda4e3e4a3d42393e1eb Mon Sep 17 00:00:00 2001
From: Bruce Weirdan <weirdan@gmail.com>
Date: Sun, 23 Jul 2023 01:19:39 +0200
Subject: [PATCH 07/11] CS fix

---
 .../Internal/LanguageServer/PathMapper.php    | 40 +++++++++----------
 tests/LanguageServer/PathMapperTest.php       | 36 ++++++++---------
 2 files changed, 38 insertions(+), 38 deletions(-)

diff --git a/src/Psalm/Internal/LanguageServer/PathMapper.php b/src/Psalm/Internal/LanguageServer/PathMapper.php
index 8d9a09bdb89..88ff1661d2c 100644
--- a/src/Psalm/Internal/LanguageServer/PathMapper.php
+++ b/src/Psalm/Internal/LanguageServer/PathMapper.php
@@ -5,45 +5,45 @@
 /** @internal */
 final class PathMapper
 {
-    private string $serverRoot;
-    private ?string $clientRoot;
+    private string $server_root;
+    private ?string $client_root;
 
-    public function __construct(string $serverRoot, ?string $clientRoot = null)
+    public function __construct(string $server_root, ?string $client_root = null)
     {
-        $this->serverRoot = $this->sanitizeFolderPath($serverRoot);
-        $this->clientRoot = $this->sanitizeFolderPath($clientRoot);
+        $this->server_root = $this->sanitizeFolderPath($server_root);
+        $this->client_root = $this->sanitizeFolderPath($client_root);
     }
 
-    public function configureClientRoot(string $clientRoot): void
+    public function configureClientRoot(string $client_root): void
     {
         // ignore if preconfigured
-        if ($this->clientRoot === null) {
-            $this->clientRoot = $this->sanitizeFolderPath($clientRoot);
+        if ($this->client_root === null) {
+            $this->client_root = $this->sanitizeFolderPath($client_root);
         }
     }
 
-    public function mapClientToServer(string $clientPath): string
+    public function mapClientToServer(string $client_path): string
     {
-        if ($this->clientRoot === null) {
-            return $clientPath;
+        if ($this->client_root === null) {
+            return $client_path;
         }
 
-        if (substr($clientPath, 0, strlen($this->clientRoot)) === $this->clientRoot) {
-            return $this->serverRoot . substr($clientPath, strlen($this->clientRoot));
+        if (substr($client_path, 0, strlen($this->client_root)) === $this->client_root) {
+            return $this->server_root . substr($client_path, strlen($this->client_root));
         }
 
-        return $clientPath;
+        return $client_path;
     }
 
-    public function mapServerToClient(string $serverPath): string
+    public function mapServerToClient(string $server_path): string
     {
-        if ($this->clientRoot === null) {
-            return $serverPath;
+        if ($this->client_root === null) {
+            return $server_path;
         }
-        if (substr($serverPath, 0, strlen($this->serverRoot)) === $this->serverRoot) {
-            return $this->clientRoot . substr($serverPath, strlen($this->serverRoot));
+        if (substr($server_path, 0, strlen($this->server_root)) === $this->server_root) {
+            return $this->client_root . substr($server_path, strlen($this->server_root));
         }
-        return $serverPath;
+        return $server_path;
     }
 
     /** @return ($path is null ? null : string) */
diff --git a/tests/LanguageServer/PathMapperTest.php b/tests/LanguageServer/PathMapperTest.php
index c6a45a1b759..ac6e1fd5c32 100644
--- a/tests/LanguageServer/PathMapperTest.php
+++ b/tests/LanguageServer/PathMapperTest.php
@@ -33,33 +33,33 @@ public function testIgnoresClientRootIfItWasPreconfigures(): void
      * @dataProvider mappingProvider
      */
     public function testMapsClientToServer(
-        string $serverRoot,
-        ?string $clientRootPreconfigured,
-        string $clientRootProvidedLater,
-        string $clientPath,
-        string $serverPath
+        string $server_root,
+        ?string $client_root_reconfigured,
+        string $client_root_provided_later,
+        string $client_path,
+        string $server_ath
     ): void {
-        $mapper = new PathMapper($serverRoot, $clientRootPreconfigured);
-        $mapper->configureClientRoot($clientRootProvidedLater);
+        $mapper = new PathMapper($server_root, $client_root_reconfigured);
+        $mapper->configureClientRoot($client_root_provided_later);
         $this->assertSame(
-            $serverPath,
-            $mapper->mapClientToServer($clientPath)
+            $server_ath,
+            $mapper->mapClientToServer($client_path)
         );
     }
 
     /** @dataProvider mappingProvider */
     public function testMapsServerToClient(
-        string $serverRoot,
-        ?string $clientRootPreconfigured,
-        string $clientRootProvidedLater,
-        string $clientPath,
-        string $serverPath
+        string $server_root,
+        ?string $client_root_preconfigured,
+        string $client_root_provided_later,
+        string $client_path,
+        string $server_path
     ): void {
-        $mapper = new PathMapper($serverRoot, $clientRootPreconfigured);
-        $mapper->configureClientRoot($clientRootProvidedLater);
+        $mapper = new PathMapper($server_root, $client_root_preconfigured);
+        $mapper->configureClientRoot($client_root_provided_later);
         $this->assertSame(
-            $clientPath,
-            $mapper->mapServerToClient($serverPath)
+            $client_path,
+            $mapper->mapServerToClient($server_path)
         );
     }
 

From 6eb7a688d1e682753cf5ea5ba778ebd817612564 Mon Sep 17 00:00:00 2001
From: Bruce Weirdan <weirdan@gmail.com>
Date: Sun, 23 Jul 2023 02:10:49 +0200
Subject: [PATCH 08/11] Introduce `--map-folder` switch

And create PathMapper based on its value
---
 src/Psalm/Internal/Cli/LanguageServer.php     | 67 ++++++++++++++++++-
 .../LanguageServer/LanguageServer.php         | 13 ++--
 tests/LanguageServer/DiagnosticTest.php       |  3 +-
 3 files changed, 73 insertions(+), 10 deletions(-)

diff --git a/src/Psalm/Internal/Cli/LanguageServer.php b/src/Psalm/Internal/Cli/LanguageServer.php
index cc52be7a7d4..026d67efda5 100644
--- a/src/Psalm/Internal/Cli/LanguageServer.php
+++ b/src/Psalm/Internal/Cli/LanguageServer.php
@@ -10,6 +10,7 @@
 use Psalm\Internal\IncludeCollector;
 use Psalm\Internal\LanguageServer\ClientConfiguration;
 use Psalm\Internal\LanguageServer\LanguageServer as LanguageServerLanguageServer;
+use Psalm\Internal\LanguageServer\PathMapper;
 use Psalm\Report;
 
 use function array_key_exists;
@@ -75,6 +76,7 @@ public static function run(array $argv): void
             'find-dead-code',
             'help',
             'root:',
+            'map-folder::',
             'use-ini-defaults',
             'version',
             'tcp:',
@@ -127,6 +129,14 @@ static function (string $arg) use ($valid_long_options): void {
 
         // get options from command line
         $options = getopt(implode('', $valid_short_options), $valid_long_options);
+        if ($options === false) {
+            // shouldn't really happen, but just in case
+            fwrite(
+                STDERR,
+                'Failed to get CLI args' . PHP_EOL,
+            );
+            exit(1);
+        }
 
         if (!array_key_exists('use-ini-defaults', $options)) {
             ini_set('display_errors', '1');
@@ -169,6 +179,14 @@ static function (string $arg) use ($valid_long_options): void {
                 -r, --root
                     If running Psalm globally you'll need to specify a project root. Defaults to cwd
 
+                --map-folder[=SERVER_FOLDER:CLIENT_FOLDER]
+                    Specify folder to map between the client and the server. Use this when the client
+                    and server have different views of the filesystem (e.g. in a docker container).
+                    Defaults to mapping the rootUri provided by the client to the server's cwd,
+                    or `-r` if provided.
+
+                    No mapping is done when this option is not specified.
+
                 --find-dead-code
                     Look for dead code
 
@@ -254,8 +272,6 @@ static function (string $arg) use ($valid_long_options): void {
             $current_dir = $root_path . DIRECTORY_SEPARATOR;
         }
 
-        $server_start_dir = $current_dir;
-
         $vendor_dir = CliUtils::getVendorDir($current_dir);
 
         $include_collector = new IncludeCollector();
@@ -293,6 +309,8 @@ static function (string $arg) use ($valid_long_options): void {
 
         setlocale(LC_CTYPE, 'C');
 
+        $path_mapper = self::createPathMapper($options, $current_dir);
+
         $path_to_config = CliUtils::getPathToConfig($options);
 
         if (isset($options['tcp'])) {
@@ -396,6 +414,49 @@ static function (string $arg) use ($valid_long_options): void {
         $clientConfiguration->TCPServerAddress = $options['tcp'] ?? null;
         $clientConfiguration->TCPServerMode = isset($options['tcp-server']);
 
-        LanguageServerLanguageServer::run($config, $clientConfiguration, $current_dir, $server_start_dir, $inMemory);
+        LanguageServerLanguageServer::run($config, $clientConfiguration, $current_dir, $path_mapper, $inMemory);
+    }
+
+    /** @param array<string,string|false|list<string|false>> $options */
+    private static function createPathMapper(array $options, string $server_start_dir): PathMapper
+    {
+        if (!isset($options['map-folder'])) {
+            // dummy no-op mapper
+            return new PathMapper('/', '/');
+        }
+
+        $map_folder = $options['map-folder'];
+
+        if ($map_folder === false) {
+            // autoconfigured mapper
+            return new PathMapper($server_start_dir, null);
+        }
+
+        if (is_string($map_folder)) {
+            if (strpos($map_folder, ':') === false) {
+                fwrite(
+                    STDERR,
+                    'invalid format for --map-folder option' . PHP_EOL,
+                );
+                exit(1);
+            }
+            /** @psalm-suppress PossiblyUndefinedArrayOffset we just checked that we have the separator*/
+            [$server_dir, $client_dir] = explode(':', $map_folder, 2);
+            if (!strlen($server_dir) || !strlen($client_dir)) {
+                fwrite(
+                    STDERR,
+                    'invalid format for --map-folder option, '
+                    . 'neither SERVER_FOLDER nor CLIENT_FOLDER can be empty' . PHP_EOL,
+                );
+                exit(1);
+            }
+            return new PathMapper($server_dir, $client_dir);
+        }
+
+        fwrite(
+            STDERR,
+            '--map-folder option can only be specified once' . PHP_EOL,
+        );
+        exit(1);
     }
 }
diff --git a/src/Psalm/Internal/LanguageServer/LanguageServer.php b/src/Psalm/Internal/LanguageServer/LanguageServer.php
index 4ffe03af380..13dc3c993d7 100644
--- a/src/Psalm/Internal/LanguageServer/LanguageServer.php
+++ b/src/Psalm/Internal/LanguageServer/LanguageServer.php
@@ -153,7 +153,7 @@ public function __construct(
         Codebase $codebase,
         ClientConfiguration $clientConfiguration,
         Progress $progress,
-        string $server_start_dir
+        PathMapper $path_mapper
     ) {
         parent::__construct($this, '/');
 
@@ -163,6 +163,8 @@ public function __construct(
 
         $this->codebase = $codebase;
 
+        $this->path_mapper = $path_mapper;
+
         $this->protocolWriter = $writer;
 
         $this->protocolReader = $reader;
@@ -245,7 +247,6 @@ function (): void {
 
         $this->client = new LanguageClient($reader, $writer, $this, $clientConfiguration);
 
-        $this->path_mapper = new PathMapper($server_start_dir, null);
 
         $this->logInfo("Psalm Language Server ".PSALM_VERSION." has started.");
     }
@@ -257,7 +258,7 @@ public static function run(
         Config $config,
         ClientConfiguration $clientConfiguration,
         string $base_dir,
-        string $server_start_dir,
+        PathMapper $path_mapper,
         bool $inMemory = false
     ): void {
         $progress = new Progress();
@@ -330,7 +331,7 @@ public static function run(
                 $codebase,
                 $clientConfiguration,
                 $progress,
-                $server_start_dir,
+                $path_mapper,
             );
             Loop::run();
         } elseif ($clientConfiguration->TCPServerMode && $clientConfiguration->TCPServerAddress) {
@@ -354,7 +355,7 @@ public static function run(
                     $codebase,
                     $clientConfiguration,
                     $progress,
-                    $server_start_dir,
+                    $path_mapper,
                 );
                 Loop::run();
             }
@@ -368,7 +369,7 @@ public static function run(
                 $codebase,
                 $clientConfiguration,
                 $progress,
-                $server_start_dir,
+                $path_mapper,
             );
             Loop::run();
         }
diff --git a/tests/LanguageServer/DiagnosticTest.php b/tests/LanguageServer/DiagnosticTest.php
index ea480138c20..470bc68199e 100644
--- a/tests/LanguageServer/DiagnosticTest.php
+++ b/tests/LanguageServer/DiagnosticTest.php
@@ -9,6 +9,7 @@
 use Psalm\Internal\LanguageServer\ClientConfiguration;
 use Psalm\Internal\LanguageServer\LanguageServer;
 use Psalm\Internal\LanguageServer\Message;
+use Psalm\Internal\LanguageServer\PathMapper;
 use Psalm\Internal\LanguageServer\Progress;
 use Psalm\Internal\Provider\FakeFileProvider;
 use Psalm\Internal\Provider\Providers;
@@ -85,7 +86,7 @@ public function testSnippetSupportDisabled(): void
             $this->codebase,
             $clientConfiguration,
             new Progress,
-            getcwd(),
+            new PathMapper(getcwd(), getcwd()),
         );
 
         $write->on('message', function (Message $message) use ($deferred, $server): void {

From 0a2a0feaf233df92253e8b3725825a5b3309091e Mon Sep 17 00:00:00 2001
From: Bruce Weirdan <weirdan@gmail.com>
Date: Sun, 23 Jul 2023 02:16:44 +0200
Subject: [PATCH 09/11] CS fix

---
 src/Psalm/Internal/Cli/LanguageServer.php        | 2 ++
 src/Psalm/Internal/LanguageServer/PathMapper.php | 4 ++++
 tests/LanguageServer/DiagnosticTest.php          | 1 +
 tests/LanguageServer/PathMapperTest.php          | 8 ++++----
 4 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/src/Psalm/Internal/Cli/LanguageServer.php b/src/Psalm/Internal/Cli/LanguageServer.php
index 026d67efda5..07d5e6f93e8 100644
--- a/src/Psalm/Internal/Cli/LanguageServer.php
+++ b/src/Psalm/Internal/Cli/LanguageServer.php
@@ -19,6 +19,7 @@
 use function array_slice;
 use function chdir;
 use function error_log;
+use function explode;
 use function fwrite;
 use function gc_disable;
 use function getcwd;
@@ -32,6 +33,7 @@
 use function preg_replace;
 use function realpath;
 use function setlocale;
+use function strlen;
 use function strpos;
 use function strtolower;
 use function substr;
diff --git a/src/Psalm/Internal/LanguageServer/PathMapper.php b/src/Psalm/Internal/LanguageServer/PathMapper.php
index 88ff1661d2c..bd4b815bc94 100644
--- a/src/Psalm/Internal/LanguageServer/PathMapper.php
+++ b/src/Psalm/Internal/LanguageServer/PathMapper.php
@@ -2,6 +2,10 @@
 
 namespace Psalm\Internal\LanguageServer;
 
+use function rtrim;
+use function strlen;
+use function substr;
+
 /** @internal */
 final class PathMapper
 {
diff --git a/tests/LanguageServer/DiagnosticTest.php b/tests/LanguageServer/DiagnosticTest.php
index 470bc68199e..b40ef38ace3 100644
--- a/tests/LanguageServer/DiagnosticTest.php
+++ b/tests/LanguageServer/DiagnosticTest.php
@@ -23,6 +23,7 @@
 use Psalm\Tests\TestConfig;
 
 use function Amp\Promise\wait;
+use function getcwd;
 use function rand;
 
 class DiagnosticTest extends AsyncTestCase
diff --git a/tests/LanguageServer/PathMapperTest.php b/tests/LanguageServer/PathMapperTest.php
index ac6e1fd5c32..2e64b356399 100644
--- a/tests/LanguageServer/PathMapperTest.php
+++ b/tests/LanguageServer/PathMapperTest.php
@@ -13,7 +13,7 @@ public function testUsesUpdatedClientRoot(): void
         $mapper->configureClientRoot('/home/user/src/project');
         $this->assertSame(
             '/home/user/src/project/filename.php',
-            $mapper->mapServerToClient('/var/www/filename.php')
+            $mapper->mapServerToClient('/var/www/filename.php'),
         );
     }
 
@@ -25,7 +25,7 @@ public function testIgnoresClientRootIfItWasPreconfigures(): void
 
         $this->assertSame(
             '/home/user/src/project/filename.php',
-            $mapper->mapServerToClient('/var/www/filename.php')
+            $mapper->mapServerToClient('/var/www/filename.php'),
         );
     }
 
@@ -43,7 +43,7 @@ public function testMapsClientToServer(
         $mapper->configureClientRoot($client_root_provided_later);
         $this->assertSame(
             $server_ath,
-            $mapper->mapClientToServer($client_path)
+            $mapper->mapClientToServer($client_path),
         );
     }
 
@@ -59,7 +59,7 @@ public function testMapsServerToClient(
         $mapper->configureClientRoot($client_root_provided_later);
         $this->assertSame(
             $client_path,
-            $mapper->mapServerToClient($server_path)
+            $mapper->mapServerToClient($server_path),
         );
     }
 

From bb102760ea2bb901af3927d1a211171a0715c7a7 Mon Sep 17 00:00:00 2001
From: Bruce Weirdan <weirdan@gmail.com>
Date: Sun, 23 Jul 2023 02:18:56 +0200
Subject: [PATCH 10/11] Drop unused property

---
 src/Psalm/Internal/LanguageServer/LanguageServer.php | 2 --
 1 file changed, 2 deletions(-)

diff --git a/src/Psalm/Internal/LanguageServer/LanguageServer.php b/src/Psalm/Internal/LanguageServer/LanguageServer.php
index 13dc3c993d7..628fb9cc253 100644
--- a/src/Psalm/Internal/LanguageServer/LanguageServer.php
+++ b/src/Psalm/Internal/LanguageServer/LanguageServer.php
@@ -142,8 +142,6 @@ class LanguageServer extends Dispatcher
      */
     protected JsonMapper $mapper;
 
-    protected ?string $clientRootPath = null;
-
     protected PathMapper $path_mapper;
 
     public function __construct(

From 5c0154c422a5207115cef95c912d289eab721057 Mon Sep 17 00:00:00 2001
From: Bruce Weirdan <weirdan@gmail.com>
Date: Sun, 23 Jul 2023 02:38:07 +0200
Subject: [PATCH 11/11] Added docs on running LS in a container

---
 docs/running_psalm/language_server.md | 25 ++++++++++++++++++-------
 1 file changed, 18 insertions(+), 7 deletions(-)

diff --git a/docs/running_psalm/language_server.md b/docs/running_psalm/language_server.md
index 47504068898..3d80a91c9d6 100644
--- a/docs/running_psalm/language_server.md
+++ b/docs/running_psalm/language_server.md
@@ -6,7 +6,9 @@ It currently supports diagnostics (i.e. finding errors and warnings), go-to-defi
 
 It works well in a variety of editors (listed alphabetically):
 
-## Emacs
+## Client configuration
+
+### Emacs
 
 I got it working with [eglot](https://github.com/joaotavora/eglot)
 
@@ -27,13 +29,13 @@ This is the config I used:
   )
 ```
 
-## PhpStorm
+### PhpStorm
 
-### Native Support
+#### Native Support
 
 As of PhpStorm 2020.3 support for psalm is supported and on by default, you can read more about that [here](https://www.jetbrains.com/help/phpstorm/using-psalm.html)
 
-### With LSP
+#### With LSP
 
 Alternatively, psalm works with `gtache/intellij-lsp` plugin ([Jetbrains-approved version](https://plugins.jetbrains.com/plugin/10209-lsp-support), [latest version](https://github.com/gtache/intellij-lsp/releases/tag/v1.6.0)).
 
@@ -51,7 +53,7 @@ In the "Server definitions" tab you should add a definition for Psalm:
 
 In the "Timeouts" tab you can adjust the initialization timeout. This is important if you have a large project. You should set the "Init" value to the number of milliseconds you allow Psalm to scan your entire project and your project's dependencies. For opening a couple of projects that use large PHP frameworks, on a high-end business laptop, try `240000` milliseconds for Init.
 
-## Sublime Text
+### Sublime Text
 
 I use the excellent Sublime [LSP plugin](https://github.com/tomv564/LSP) with the following config(Package Settings > LSP > Settings):
 ```json
@@ -64,7 +66,7 @@ I use the excellent Sublime [LSP plugin](https://github.com/tomv564/LSP) with th
     }
 ```
 
-## Vim & Neovim
+### Vim & Neovim
 
 **ALE**
 
@@ -105,6 +107,15 @@ Add settings to `coc-settings.json`:
   }
 ```
 
-## VS Code
+### VS Code
 
 [Get the Psalm plugin here](https://marketplace.visualstudio.com/items?itemName=getpsalm.psalm-vscode-plugin) (Requires VS Code 1.26+):
+
+## Running the server in a docker container
+
+Make sure you use `--map-folder` option. Using it without argument will map the server's CWD to the host's project root folder. You can also specify a custom mapping. For example:
+```bash
+docker-compose exec php /usr/share/php/psalm/psalm-language-server \
+   -r=/var/www/html \
+   --map-folder=/var/www/html:$PWD
+```