diff --git a/fixtures/signatureHelp/funcClosed.php b/fixtures/signatureHelp/funcClosed.php
new file mode 100644
index 0000000..6012844
--- /dev/null
+++ b/fixtures/signatureHelp/funcClosed.php
@@ -0,0 +1,7 @@
+<?php
+
+function helpFunc1(int $count = 0)
+{
+}
+
+helpFunc1()
diff --git a/fixtures/signatureHelp/funcNotClosed.php b/fixtures/signatureHelp/funcNotClosed.php
new file mode 100644
index 0000000..95d7ebb
--- /dev/null
+++ b/fixtures/signatureHelp/funcNotClosed.php
@@ -0,0 +1,7 @@
+<?php
+
+function helpFunc2(int $count = 0)
+{
+}
+
+helpFunc2(
diff --git a/fixtures/signatureHelp/methodClosed.php b/fixtures/signatureHelp/methodClosed.php
new file mode 100644
index 0000000..0f0890f
--- /dev/null
+++ b/fixtures/signatureHelp/methodClosed.php
@@ -0,0 +1,15 @@
+<?php
+
+class HelpClass1
+{
+    public function method(string $param = "")
+    {
+    }
+    public function test()
+    {
+        $this->method();
+    }
+}
+
+$a = new HelpClass1;
+$a->method();
diff --git a/fixtures/signatureHelp/methodNotClosed.php b/fixtures/signatureHelp/methodNotClosed.php
new file mode 100644
index 0000000..d5ce4cc
--- /dev/null
+++ b/fixtures/signatureHelp/methodNotClosed.php
@@ -0,0 +1,17 @@
+<?php
+
+class HelpClass2
+{
+    protected function method(string $param = "")
+    {
+    }
+    public function test()
+    {
+        $this->method(1,1);
+    }
+}
+$a = new HelpClass2;
+$a
+    ->method(
+        1,
+        array(),
diff --git a/fixtures/signatureHelp/staticClosed.php b/fixtures/signatureHelp/staticClosed.php
new file mode 100644
index 0000000..301009f
--- /dev/null
+++ b/fixtures/signatureHelp/staticClosed.php
@@ -0,0 +1,10 @@
+<?php
+
+class HelpClass3
+{
+    public static function method(string $param = "")
+    {
+    }
+}
+
+HelpClass3::method()
diff --git a/fixtures/signatureHelp/staticNotClosed.php b/fixtures/signatureHelp/staticNotClosed.php
new file mode 100644
index 0000000..49728aa
--- /dev/null
+++ b/fixtures/signatureHelp/staticNotClosed.php
@@ -0,0 +1,10 @@
+<?php
+
+class HelpClass4
+{
+    public static function method(string $param = "")
+    {
+    }
+}
+
+HelpClass4::method(1
diff --git a/src/Definition.php b/src/Definition.php
index d4b59cb..dab8295 100644
--- a/src/Definition.php
+++ b/src/Definition.php
@@ -89,4 +89,11 @@ class Definition
      * @var string
      */
     public $documentation;
+
+    /**
+     * Parameters array (for methods and functions), for use in textDocument/signatureHelp
+     *
+     * @var string[]
+     */
+    public $parameters;
 }
diff --git a/src/DefinitionResolver.php b/src/DefinitionResolver.php
index 8cbddf7..bb5fd6c 100644
--- a/src/DefinitionResolver.php
+++ b/src/DefinitionResolver.php
@@ -7,6 +7,7 @@ use PhpParser\Node;
 use PhpParser\PrettyPrinter\Standard as PrettyPrinter;
 use phpDocumentor\Reflection\{Types, Type, Fqsen, TypeResolver};
 use LanguageServer\Protocol\SymbolInformation;
+use LanguageServer\Protocol\ParameterInformation;
 use LanguageServer\Index\ReadableIndex;
 
 class DefinitionResolver
@@ -131,6 +132,18 @@ class DefinitionResolver
         $def->type = $this->getTypeFromNode($node);
         $def->declarationLine = $this->getDeclarationLineFromNode($node);
         $def->documentation = $this->getDocumentationFromNode($node);
+        $def->parameters = [];
+        if ($node instanceof Node\FunctionLike) {
+            foreach ($node->getParams() as $param) {
+                if (!$param->getAttribute('parentNode')) {
+                    $param->setAttribute('parentNode', $node);
+                }
+                $def->parameters[] = new ParameterInformation(
+                    $this->prettyPrinter->prettyPrint([$param]),
+                    $this->getDocumentationFromNode($param)
+                );
+            }
+        }
         return $def;
     }
 
diff --git a/src/LanguageServer.php b/src/LanguageServer.php
index 7e856b1..6969b1d 100644
--- a/src/LanguageServer.php
+++ b/src/LanguageServer.php
@@ -12,7 +12,8 @@ use LanguageServer\Protocol\{
     InitializeResult,
     SymbolInformation,
     TextDocumentIdentifier,
-    CompletionOptions
+    CompletionOptions,
+    SignatureHelpOptions
 };
 use LanguageServer\FilesFinder\{FilesFinder, ClientFilesFinder, FileSystemFilesFinder};
 use LanguageServer\ContentRetriever\{ContentRetriever, ClientContentRetriever, FileSystemContentRetriever};
@@ -259,6 +260,9 @@ class LanguageServer extends AdvancedJsonRpc\Dispatcher
             $serverCapabilities->completionProvider = new CompletionOptions;
             $serverCapabilities->completionProvider->resolveProvider = false;
             $serverCapabilities->completionProvider->triggerCharacters = ['$', '>'];
+            // Support "Signature Help"
+            $serverCapabilities->signatureHelpProvider = new SignatureHelpOptions;
+            $serverCapabilities->signatureHelpProvider->triggerCharacters = ['(',','];
             // Support global references
             $serverCapabilities->xworkspaceReferencesProvider = true;
             $serverCapabilities->xdefinitionProvider = true;
diff --git a/src/Protocol/ParameterInformation.php b/src/Protocol/ParameterInformation.php
index 89b5e53..628804a 100644
--- a/src/Protocol/ParameterInformation.php
+++ b/src/Protocol/ParameterInformation.php
@@ -23,4 +23,14 @@ class ParameterInformation
      * @var string|null
      */
     public $documentation;
+
+    /**
+     * @param string                 $label         The label of this signature. Will be shown in the UI.
+     * @param string|null            $documentation The human-readable doc-comment of this signature.
+     */
+    public function __construct(string $label = null, string $documentation = null)
+    {
+        $this->label = $label;
+        $this->documentation = $documentation;
+    }
 }
diff --git a/src/Protocol/SignatureHelp.php b/src/Protocol/SignatureHelp.php
index 407b25a..9c6f3ea 100644
--- a/src/Protocol/SignatureHelp.php
+++ b/src/Protocol/SignatureHelp.php
@@ -29,4 +29,16 @@ class SignatureHelp
      * @var int|null
      */
     public $activeParameter;
+
+    /**
+     * @param SignatureInformation[] $signatures      The signatures.
+     * @param int|null               $activeSignature The active signature.
+     * @param int|null               $activeParameter The active parameter of the active signature.
+     */
+    public function __construct(array $signatures = [], int $activeSignature = null, int $activeParameter = null)
+    {
+        $this->signatures = $signatures;
+        $this->activeSignature = $activeSignature;
+        $this->activeParameter = $activeParameter;
+    }
 }
diff --git a/src/Protocol/SignatureInformation.php b/src/Protocol/SignatureInformation.php
index 77e152c..e1d4273 100644
--- a/src/Protocol/SignatureInformation.php
+++ b/src/Protocol/SignatureInformation.php
@@ -31,4 +31,16 @@ class SignatureInformation
      * @var ParameterInformation[]|null
      */
     public $parameters;
+
+    /**
+     * @param string                      $label         The label of this signature. Will be shown in the UI.
+     * @param string|null                 $documentation The human-readable doc-comment of this signature.
+     * @param ParameterInformation[]|null $parameters    The parameters of this signature.
+     */
+    public function __construct(string $label = null, string $documentation = null, array $parameters = null)
+    {
+        $this->label = $label;
+        $this->documentation = $documentation;
+        $this->parameters = $parameters;
+    }
 }
diff --git a/src/Server/TextDocument.php b/src/Server/TextDocument.php
index 532d642..0952696 100644
--- a/src/Server/TextDocument.php
+++ b/src/Server/TextDocument.php
@@ -5,7 +5,7 @@ namespace LanguageServer\Server;
 
 use PhpParser\PrettyPrinter\Standard as PrettyPrinter;
 use PhpParser\{Node, NodeTraverser};
-use LanguageServer\{LanguageClient, PhpDocumentLoader, PhpDocument, DefinitionResolver, CompletionProvider};
+use LanguageServer\{LanguageClient, PhpDocumentLoader, PhpDocument, DefinitionResolver, CompletionProvider, SignatureHelpProvider};
 use LanguageServer\NodeVisitor\VariableReferencesCollector;
 use LanguageServer\Protocol\{
     SymbolLocationInformation,
@@ -64,6 +64,11 @@ class TextDocument
      */
     protected $completionProvider;
 
+    /**
+     * @var SignatureHelpProvider
+     */
+    protected $signatureHelpProvider;
+
     /**
      * @var ReadableIndex
      */
@@ -100,6 +105,7 @@ class TextDocument
         $this->prettyPrinter = new PrettyPrinter();
         $this->definitionResolver = $definitionResolver;
         $this->completionProvider = new CompletionProvider($this->definitionResolver, $index);
+        $this->signatureHelpProvider = new SignatureHelpProvider($this->definitionResolver, $index);
         $this->index = $index;
         $this->composerJson = $composerJson;
         $this->composerLock = $composerLock;
@@ -363,6 +369,14 @@ class TextDocument
         });
     }
 
+    public function signatureHelp(TextDocumentIdentifier $textDocument, Position $position): Promise
+    {
+        return coroutine(function () use ($textDocument, $position) {
+            $document = yield $this->documentLoader->getOrLoad($textDocument->uri);
+            return $this->signatureHelpProvider->provideSignature($document, $position);
+        });
+    }
+
     /**
      * This method is the same as textDocument/definition, except that
      *
diff --git a/src/SignatureHelpProvider.php b/src/SignatureHelpProvider.php
new file mode 100644
index 0000000..c29c2e8
--- /dev/null
+++ b/src/SignatureHelpProvider.php
@@ -0,0 +1,199 @@
+<?php
+declare(strict_types = 1);
+
+namespace LanguageServer;
+
+use PhpParser\ErrorHandler\Collecting;
+use PhpParser\Node;
+use LanguageServer\Index\ReadableIndex;
+use LanguageServer\Protocol\{
+    Range,
+    Position,
+    SignatureHelp,
+    SignatureInformation,
+    ParameterInformation
+};
+
+class SignatureHelpProvider
+{
+    /**
+     * @var DefinitionResolver
+     */
+    private $definitionResolver;
+
+    /**
+     * @var ReadableIndex
+     */
+    private $index;
+
+    /**
+     * @param DefinitionResolver $definitionResolver
+     * @param ReadableIndex      $index
+     */
+    public function __construct(DefinitionResolver $definitionResolver, ReadableIndex $index)
+    {
+        $this->definitionResolver = $definitionResolver;
+        $this->index = $index;
+    }
+
+    /**
+     * Returns signature help for a specific cursor position in a document
+     *
+     * @param PhpDocument $doc The opened document
+     * @param Position $pos The cursor position
+     * @return SignatureHelp
+     */
+    public function provideSignature(PhpDocument $doc, Position $pos) : SignatureHelp
+    {
+        $handle = fopen('php://temp', 'r+');
+        fwrite($handle, $doc->getContent());
+        fseek($handle, 0);
+
+        $lines = [];
+        for ($i = 0; $i < $pos->line; $i++) {
+            $lines[] = strlen(fgets($handle));
+        }
+        $filePos = ftell($handle) + $pos->character;
+        $line = substr(fgets($handle), 0, $pos->character);
+        fseek($handle, 0);
+
+        $i = 0;
+        $orig = null;
+        do {
+            $node = $doc->getNodeAtPosition($pos);
+            if ($node !== null && $orig === null) {
+                $orig = $node;
+            }
+            $pos->character--;
+            if ($pos->character < 0) {
+                $pos->line --;
+                if ($pos->line < 0) {
+                    break;
+                }
+                $pos->character = $lines[$pos->line];
+            }
+        } while (!(
+            $node instanceof Node\Expr\PropertyFetch ||
+            $node instanceof Node\Expr\MethodCall ||
+            $node instanceof Node\Expr\FuncCall ||
+            $node instanceof Node\Expr\ClassConstFetch ||
+            $node instanceof Node\Expr\StaticCall
+        ) && ++$i < 120);
+
+        if ($node === null) {
+            $node = $orig;
+        }
+
+        if ($node === null) {
+            fclose($handle);
+            return new SignatureHelp;
+        }
+
+        $params = '';
+        if ($node instanceof Node\Expr\PropertyFetch) {
+            fseek($handle, $node->name->getAttribute('startFilePos'));
+            $method = fread($handle, ($node->name->getAttribute('endFilePos') + 1) - $node->name->getAttribute('startFilePos'));
+            fseek($handle, $node->name->getAttribute('endFilePos') + 1);
+            $params = fread($handle, ($filePos - 1) - $node->name->getAttribute('endFilePos'));
+            if ($def = $this->definitionResolver->resolveReferenceNodeToDefinition($node->var)) {
+                $fqn = $def->fqn;
+                if (!$fqn) {
+                    $fqns = DefinitionResolver::getFqnsFromType(
+                        $this->definitionResolver->resolveExpressionNodeToType($node->var)
+                    );
+                    if (count($fqns)) {
+                        $fqn = $fqns[0];
+                    }
+                }
+                if ($fqn) {
+                    $fqn = $fqn . '->' . $method . '()';
+                    $def = $this->index->getDefinition($fqn);
+                }
+            }
+        } else if ($node instanceof Node\Expr\MethodCall) {
+            fseek($handle, $node->getAttribute('startFilePos'));
+            $params = explode('(', fread($handle, $filePos - $node->getAttribute('startFilePos')), 2)[1];
+            $def = $this->definitionResolver->resolveReferenceNodeToDefinition($node);
+        } else if ($node instanceof Node\Expr\FuncCall) {
+            fseek($handle, $node->getAttribute('startFilePos'));
+            $params = explode('(', fread($handle, $filePos - $node->getAttribute('startFilePos')), 2)[1];
+            $fqn = $this->definitionResolver->resolveReferenceNodeToFqn($node->name);
+            $def = $this->index->getDefinition($fqn);
+        } else if ($node instanceof Node\Expr\StaticCall) {
+            fseek($handle, $node->getAttribute('startFilePos'));
+            $params = explode('(', fread($handle, $filePos - $node->getAttribute('startFilePos')), 2)[1];
+            $def = $this->definitionResolver->resolveReferenceNodeToDefinition($node);
+        } else if ($node instanceof Node\Expr\ClassConstFetch) {
+            fseek($handle, $node->name->getAttribute('endFilePos') + 2);
+            $params = fread($handle, ($filePos - 1) - $node->name->getAttribute('endFilePos'));
+            fseek($handle, $node->name->getAttribute('startFilePos'));
+            $method = fread($handle, ($node->name->getAttribute('endFilePos') + 1) - $node->name->getAttribute('startFilePos'));
+            $method = explode('::', str_replace('()', '', $method), 2);
+            $method = $method[1] ?? $method[0];
+            $fqn = $this->definitionResolver->resolveReferenceNodeToFqn($node->class);
+            $def = $this->index->getDefinition($fqn.'::'.$method.'()');
+        } else {
+            if (!preg_match('(([a-zA-Z_\x7f-\xff][:a-zA-Z0-9_\x7f-\xff]*)\s*\((.*)$)', $line, $method)) {
+                fclose($handle);
+                return new SignatureHelp;
+            }
+            $def = $this->index->getDefinition($method[1] . '()');
+            $params = $method[2];
+        }
+        fclose($handle);
+
+        if ($def) {
+            $method = preg_split('(::|->)', str_replace('()', '', $def->fqn), 2);
+            $method = $method[1] ?? $method[0];
+            $params = ltrim($params, "( ");
+            $activeParameter = 0;
+            if (strlen(trim($params))) {
+                try {
+                    $lex = new \PhpParser\Lexer();
+                    $lex->startLexing('<?php $a = [ ' . $params, new Collecting);
+                    $value = null;
+                    $lex->getNextToken($value);
+                    $lex->getNextToken($value);
+                    $lex->getNextToken($value);
+                    $params = 0;
+                    $stack = [];
+                    while ($value !== "\0") {
+                        $lex->getNextToken($value);
+                        if (($value === ")" || $value === ";") && !count($stack)) {
+                            return new SignatureHelp;
+                        }
+                        if ($value === ',' && !count($stack)) {
+                            $activeParameter++;
+                        }
+                        if ($value === '(') {
+                            $stack[] = ')';
+                        } else if ($value === '[') {
+                            $stack[] = ']';
+                        } else if (count($stack) && $value === $stack[count($stack)-1]) {
+                            array_pop($stack);
+                        }
+                    }
+                } catch (\Exception $ignore) {
+                }
+            }
+            if ($activeParameter < count($def->parameters)) {
+                $params = array_map(function ($v) {
+                    return $v->label;
+                }, $def->parameters);
+                return new SignatureHelp(
+                    [
+                        new SignatureInformation(
+                            $method . '('.implode(', ', $params).')',
+                            $def->documentation,
+                            $def->parameters
+                        )
+                    ],
+                    0,
+                    $activeParameter
+                );
+            }
+        }
+
+        return new SignatureHelp;
+    }
+}
diff --git a/tests/LanguageServerTest.php b/tests/LanguageServerTest.php
index 6bfa3c9..2f1a6e2 100644
--- a/tests/LanguageServerTest.php
+++ b/tests/LanguageServerTest.php
@@ -14,7 +14,8 @@ use LanguageServer\Protocol\{
     TextDocumentIdentifier,
     InitializeResult,
     ServerCapabilities,
-    CompletionOptions
+    CompletionOptions,
+    SignatureHelpOptions
 };
 use AdvancedJsonRpc;
 use Webmozart\Glob\Glob;
@@ -41,6 +42,8 @@ class LanguageServerTest extends TestCase
         $serverCapabilities->completionProvider = new CompletionOptions;
         $serverCapabilities->completionProvider->resolveProvider = false;
         $serverCapabilities->completionProvider->triggerCharacters = ['$', '>'];
+        $serverCapabilities->signatureHelpProvider = new SignatureHelpOptions;
+        $serverCapabilities->signatureHelpProvider->triggerCharacters = ['(',','];
         $serverCapabilities->xworkspaceReferencesProvider = true;
         $serverCapabilities->xdefinitionProvider = true;
         $serverCapabilities->xdependenciesProvider = true;
@@ -57,7 +60,7 @@ class LanguageServerTest extends TestCase
             if ($msg->body->method === 'window/logMessage' && $promise->state === Promise::PENDING) {
                 if ($msg->body->params->type === MessageType::ERROR) {
                     $promise->reject(new Exception($msg->body->params->message));
-                } else if (strpos($msg->body->params->message, 'All 25 PHP files parsed') !== false) {
+                } else if (strpos($msg->body->params->message, 'All 31 PHP files parsed') !== false) {
                     $promise->fulfill();
                 }
             }
@@ -103,7 +106,7 @@ class LanguageServerTest extends TestCase
                     if ($promise->state === Promise::PENDING) {
                         $promise->reject(new Exception($msg->body->params->message));
                     }
-                } else if (strpos($msg->body->params->message, 'All 25 PHP files parsed') !== false) {
+                } else if (strpos($msg->body->params->message, 'All 31 PHP files parsed') !== false) {
                     if ($run === 1) {
                         $run++;
                     } else {
diff --git a/tests/Server/TextDocument/SignatureHelpTest.php b/tests/Server/TextDocument/SignatureHelpTest.php
new file mode 100644
index 0000000..3814c09
--- /dev/null
+++ b/tests/Server/TextDocument/SignatureHelpTest.php
@@ -0,0 +1,222 @@
+<?php
+declare(strict_types = 1);
+
+namespace LanguageServer\Tests\Server\TextDocument;
+
+use PHPUnit\Framework\TestCase;
+use LanguageServer\Tests\MockProtocolStream;
+use LanguageServer\{Server, LanguageClient, PhpDocumentLoader, CompletionProvider, DefinitionResolver};
+use LanguageServer\Index\{Index, ProjectIndex, DependenciesIndex, GlobalIndex, StubsIndex};
+use LanguageServer\ContentRetriever\FileSystemContentRetriever;
+use LanguageServer\Protocol\{
+    TextDocumentIdentifier,
+    TextEdit,
+    Range,
+    Position,
+    ClientCapabilities,
+    SignatureHelp,
+    SignatureInformation,
+    ParameterInformation
+};
+use function LanguageServer\pathToUri;
+
+class SignatureHelpTest extends TestCase
+{
+    /**
+     * @var Server\TextDocument
+     */
+    private $textDocument;
+
+    /**
+     * @var PhpDocumentLoader
+     */
+    private $loader;
+
+    public function setUp()
+    {
+        $client = new LanguageClient(new MockProtocolStream, new MockProtocolStream);
+        $projectIndex = new ProjectIndex(new Index, new DependenciesIndex);
+        $definitionResolver = new DefinitionResolver($projectIndex);
+        $contentRetriever = new FileSystemContentRetriever;
+        $this->loader = new PhpDocumentLoader($contentRetriever, $projectIndex, $definitionResolver);
+        $this->loader->load(pathToUri(__DIR__ . '/../../../fixtures/global_symbols.php'))->wait();
+        $this->loader->load(pathToUri(__DIR__ . '/../../../fixtures/symbols.php'))->wait();
+        $this->textDocument = new Server\TextDocument($this->loader, $definitionResolver, $client, $projectIndex);
+    }
+
+    public function testMethodClosed()
+    {
+        $completionUri = pathToUri(__DIR__ . '/../../../fixtures/signatureHelp/methodClosed.php');
+        $this->loader->open($completionUri, file_get_contents($completionUri));
+        $result = $this->textDocument->signatureHelp(
+            new TextDocumentIdentifier($completionUri),
+            new Position(9, 22)
+        )->wait();
+
+        $this->assertEquals(new SignatureHelp(
+            [
+                new SignatureInformation(
+                    'method(string $param = "")',
+                    null,
+                    [
+                        new ParameterInformation('string $param = ""')
+                    ]
+                )
+            ]
+        ), $result);
+    }
+
+    public function testMethodClosedReference()
+    {
+        $completionUri = pathToUri(__DIR__ . '/../../../fixtures/signatureHelp/methodClosed.php');
+        $this->loader->open($completionUri, file_get_contents($completionUri));
+        $result = $this->textDocument->signatureHelp(
+            new TextDocumentIdentifier($completionUri),
+            new Position(14, 11)
+        )->wait();
+
+        $this->assertEquals(new SignatureHelp(
+            [
+                new SignatureInformation(
+                    'method(string $param = "")',
+                    null,
+                    [
+                        new ParameterInformation('string $param = ""')
+                    ]
+                )
+            ]
+        ), $result);
+    }
+
+    public function testMethodNotClosed()
+    {
+        $completionUri = pathToUri(__DIR__ . '/../../../fixtures/signatureHelp/methodNotClosed.php');
+        $this->loader->open($completionUri, file_get_contents($completionUri));
+        $result = $this->textDocument->signatureHelp(
+            new TextDocumentIdentifier($completionUri),
+            new Position(9, 22)
+        )->wait();
+
+        $this->assertEquals(new SignatureHelp(
+            [
+                new SignatureInformation(
+                    'method(string $param = "")',
+                    null,
+                    [
+                        new ParameterInformation('string $param = ""')
+                    ]
+                )
+            ]
+        ), $result);
+    }
+
+    public function testMethodNotClosedReference()
+    {
+        $completionUri = pathToUri(__DIR__ . '/../../../fixtures/signatureHelp/methodNotClosed.php');
+        $this->loader->open($completionUri, file_get_contents($completionUri));
+        $result = $this->textDocument->signatureHelp(
+            new TextDocumentIdentifier($completionUri),
+            new Position(14, 14)
+        )->wait();
+
+        $this->assertEquals(new SignatureHelp(
+            [
+                new SignatureInformation(
+                    'method(string $param = "")',
+                    null,
+                    [
+                        new ParameterInformation('string $param = ""')
+                    ]
+                )
+            ]
+        ), $result);
+    }
+
+    public function testFuncClosed()
+    {
+        $completionUri = pathToUri(__DIR__ . '/../../../fixtures/signatureHelp/funcClosed.php');
+        $this->loader->open($completionUri, file_get_contents($completionUri));
+        $result = $this->textDocument->signatureHelp(
+            new TextDocumentIdentifier($completionUri),
+            new Position(6, 10)
+        )->wait();
+
+        $this->assertEquals(new SignatureHelp(
+            [
+                new SignatureInformation(
+                    'helpFunc1(int $count = 0)',
+                    null,
+                    [
+                        new ParameterInformation('int $count = 0')
+                    ]
+                )
+            ]
+        ), $result);
+    }
+
+    public function testFuncNotClosed()
+    {
+        $completionUri = pathToUri(__DIR__ . '/../../../fixtures/signatureHelp/funcNotClosed.php');
+        $this->loader->open($completionUri, file_get_contents($completionUri));
+        $result = $this->textDocument->signatureHelp(
+            new TextDocumentIdentifier($completionUri),
+            new Position(6, 10)
+        )->wait();
+
+        $this->assertEquals(new SignatureHelp(
+            [
+                new SignatureInformation(
+                    'helpFunc2(int $count = 0)',
+                    null,
+                    [
+                        new ParameterInformation('int $count = 0')
+                    ]
+                )
+            ]
+        ), $result);
+    }
+
+    public function testStaticClosed()
+    {
+        $completionUri = pathToUri(__DIR__ . '/../../../fixtures/signatureHelp/staticClosed.php');
+        $this->loader->open($completionUri, file_get_contents($completionUri));
+        $result = $this->textDocument->signatureHelp(
+            new TextDocumentIdentifier($completionUri),
+            new Position(9, 19)
+        )->wait();
+
+        $this->assertEquals(new SignatureHelp(
+            [
+                new SignatureInformation(
+                    'method(string $param = "")',
+                    null,
+                    [
+                        new ParameterInformation('string $param = ""')
+                    ]
+                )
+            ]
+        ), $result);
+    }
+
+    public function testStaticNotClosed()
+    {
+        $completionUri = pathToUri(__DIR__ . '/../../../fixtures/signatureHelp/staticNotClosed.php');
+        $this->loader->open($completionUri, file_get_contents($completionUri));
+        $result = $this->textDocument->signatureHelp(
+            new TextDocumentIdentifier($completionUri),
+            new Position(9, 19)
+        )->wait();
+
+        $this->assertEquals(new SignatureHelp(
+            [
+                new SignatureInformation(
+                    'method(string $param = "")',
+                    null,
+                    [
+                        new ParameterInformation('string $param = ""')
+                    ]
+                )
+            ]
+        ), $result);
+    }
+}