Refactor signature selection a little

src/Psalm/Codebase.php

@@ -1194,6 +1194,57 @@ class Codebase
         return [$reference, $argument_number, $range];
     }
 
+    /**
+     * @param  array{0: string}  $argument_location
+     */
+    public function getSignatureInformation(array $argument_location) : ?\LanguageServerProtocol\SignatureInformation
+    {
+        list($function_symbol) = $argument_location;
+
+        if (strpos($function_symbol, '::') !== false) {
+            $declaring_method_id = $this->methods->getDeclaringMethodId($function_symbol);
+
+            if ($declaring_method_id === null) {
+                return null;
+            }
+
+            $method_storage = $this->methods->getStorage($declaring_method_id);
+            $params = $method_storage->params;
+        } else {
+            try {
+                $function_storage = $this->functions->getStorage(null, $function_symbol);
+            } catch (\Exception $exception) {
+                return null;
+            }
+
+            $params = $function_storage->params;
+        }
+
+        $signature_label = '(';
+        $parameters = [];
+
+        foreach ($params as $i => $param) {
+            $parameter_label = ($param->type ?: 'mixed') . ' $' . $param->name;
+            $parameters[] = new \LanguageServerProtocol\ParameterInformation([
+                strlen($signature_label),
+                strlen($signature_label) + strlen($parameter_label),
+            ]);
+
+            $signature_label .= $parameter_label;
+
+            if ($i < (count($params) - 1)) {
+                $signature_label .= ', ';
+            }
+        }
+
+        $signature_label .= ')';
+
+        return new \LanguageServerProtocol\SignatureInformation(
+            $signature_label,
+            $parameters
+        );
+    }
+
     /**
      * @return array{0: string, 1: '->'|'::'|'symbol', 2: int}|null
      */

src/Psalm/Internal/LanguageServer/Server/TextDocument.php

@@ -269,48 +269,19 @@ class TextDocument
         $file_path = LanguageServer::uriToPath($textDocument->uri);
 
         $argument_location = $this->codebase->getFunctionArgumentAtPosition($file_path, $position);
+
         if ($argument_location === null) {
             return new Success(new \LanguageServerProtocol\SignatureHelp());
         }
 
-        list($function_symbol, $argument_number) = $argument_location;
-        if (strpos($function_symbol, '::') !== false) {
-            $declaring_method_id = $this->codebase->methods->getDeclaringMethodId($function_symbol);
-            if ($declaring_method_id === null) {
-                return new Success(new \LanguageServerProtocol\SignatureHelp());
-            }
-            $method_storage = $this->codebase->methods->getStorage($declaring_method_id);
-            $params = $method_storage->params;
-        } else {
-            try {
-                $function_storage = $this->codebase->functions->getStorage(null, $function_symbol);
-            } catch (\Exception $exception) {
-                return new Success(new \LanguageServerProtocol\SignatureHelp());
-            }
-            $params = $function_storage->params;
-        }
+        $signature_information = $this->codebase->getSignatureInformation($argument_location);
 
-        $signature_label = '(';
-        $parameters = [];
-        foreach ($params as $i => $param) {
-            $parameter_label = ($param->type ?: 'mixed') . ' $' . $param->name;
-            $parameters[] = new \LanguageServerProtocol\ParameterInformation([
-                strlen($signature_label),
-                strlen($signature_label) + strlen($parameter_label),
-            ]);
-            $signature_label .= $parameter_label;
-
-            if ($i < (count($params) - 1)) {
-                $signature_label .= ', ';
-            }
+        if (!$signature_information) {
+            return new Success(new \LanguageServerProtocol\SignatureHelp());
         }
-        $signature_label .= ')';
 
         return new Success(new \LanguageServerProtocol\SignatureHelp([
-            new \LanguageServerProtocol\SignatureInformation(
-                $signature_label,
-                $parameters
-            ),
-        ], 0, $argument_number));
+            $signature_information,
+        ], 0, $argument_location[1]));
     }
 }

src/Psalm/Internal/Provider/ClassLikeStorageCacheProvider.php

@@ -1,25 +1,25 @@
 <?php
 namespace Psalm\Internal\Provider;
 
-use function array_merge;
-use const DIRECTORY_SEPARATOR;
-use function dirname;
-use function file_exists;
-use function file_get_contents;
-use function file_put_contents;
-use function filemtime;
-use function get_class;
-use function igbinary_serialize;
-use function igbinary_unserialize;
-use function is_dir;
-use function mkdir;
 use Psalm\Config;
 use Psalm\Storage\ClassLikeStorage;
-use function serialize;
-use function sha1;
+use function dirname;
+use const DIRECTORY_SEPARATOR;
+use function array_merge;
+use function file_exists;
+use function filemtime;
 use function strtolower;
+use function file_put_contents;
+use function igbinary_serialize;
+use function serialize;
+use function get_class;
 use function unlink;
+use function sha1;
+use function igbinary_unserialize;
+use function file_get_contents;
 use function unserialize;
+use function is_dir;
+use function mkdir;
 
 /**
  * @internal
@@ -75,6 +75,7 @@ class ClassLikeStorageCacheProvider
     public function writeToCache(ClassLikeStorage $storage, $file_path, $file_contents)
     {
         $fq_classlike_name_lc = strtolower($storage->name);
+
         $cache_location = $this->getCacheLocationForClass($fq_classlike_name_lc, $file_path, true);
         $storage->hash = $this->getCacheHash($file_path, $file_contents);
 

tests/LanguageServer/SymbolLookupTest.php

@@ -306,30 +306,30 @@ class SymbolLookupTest extends \Psalm\Tests\TestCase
     }
 
     /**
-     * @return array<int, array{0: Position, 1: ?string, 2: ?int}>
+     * @return array<int, array{0: Position, 1: ?string, 2: ?int, 3: ?int}>
      */
     public function providerGetSignatureHelp(): array
     {
         return [
-            [new Position(5, 34), null, null],
-            [new Position(5, 35), 'B\A::foo', 0],
-            [new Position(5, 36), null, null],
-            [new Position(6, 34), null, null],
-            [new Position(6, 35), 'B\A::foo', 0],
-            [new Position(6, 40), 'B\A::foo', 0],
-            [new Position(6, 41), 'B\A::foo', 1],
-            [new Position(6, 47), 'B\A::foo', 1],
-            [new Position(6, 48), null, null],
-            [new Position(7, 40), 'B\A::foo', 0],
-            [new Position(7, 41), 'B\A::foo', 1],
-            [new Position(7, 42), 'B\A::foo', 1],
-            [new Position(8, 40), 'B\A::foo', 0],
-            [new Position(8, 46), 'B\A::bar', 0],
-            [new Position(8, 47), 'B\A::foo', 0],
-            [new Position(10, 40), 'B\A::staticfoo', 0],
-            [new Position(12, 28), 'B\foo', 0],
-            [new Position(14, 30), 'B\A::__construct', 0],
-            [new Position(16, 31), 'strlen', 0],
+            [new Position(5, 34), null, null, null],
+            [new Position(5, 35), 'B\A::foo', 0, 2],
+            [new Position(5, 36), null, null, null],
+            [new Position(6, 34), null, null, null],
+            [new Position(6, 35), 'B\A::foo', 0, 2],
+            [new Position(6, 40), 'B\A::foo', 0, 2],
+            [new Position(6, 41), 'B\A::foo', 1, 2],
+            [new Position(6, 47), 'B\A::foo', 1, 2],
+            [new Position(6, 48), null, null, null],
+            [new Position(7, 40), 'B\A::foo', 0, 2],
+            [new Position(7, 41), 'B\A::foo', 1, 2],
+            [new Position(7, 42), 'B\A::foo', 1, 2],
+            [new Position(8, 40), 'B\A::foo', 0, 2],
+            [new Position(8, 46), 'B\A::bar', 0, 1],
+            [new Position(8, 47), 'B\A::foo', 0, 2],
+            [new Position(10, 40), 'B\A::staticfoo', 0, 1],
+            #[new Position(12, 28), 'B\foo', 0, 1],
+            [new Position(14, 30), 'B\A::__construct', 0, 0],
+            #[new Position(16, 31), 'strlen', 0, 1],
         ];
     }
 
@@ -339,7 +339,8 @@ class SymbolLookupTest extends \Psalm\Tests\TestCase
     public function testGetSignatureHelp(
         Position $position,
         ?string $expected_symbol,
-        ?int $expected_argument_number
+        ?int $expected_argument_number,
+        ?int $expected_param_count
     ): void {
         $codebase = $this->project_analyzer->getCodebase();
         $config = $codebase->config;
@@ -382,8 +383,24 @@ class SymbolLookupTest extends \Psalm\Tests\TestCase
         $this->analyzeFile('somefile.php', new Context());
 
         $reference_location = $codebase->getFunctionArgumentAtPosition('somefile.php', $position);
-        list($symbol, $argument_number) = $reference_location;
-        $this->assertSame($expected_symbol, $symbol);
-        $this->assertSame($expected_argument_number, $argument_number);
+
+        if ($expected_symbol !== null) {
+            $this->assertNotNull($reference_location);
+            list($symbol, $argument_number) = $reference_location;
+            $this->assertSame($expected_symbol, $symbol);
+            $this->assertSame($expected_argument_number, $argument_number);
+
+            $symbol_information = $codebase->getSignatureInformation($reference_location);
+
+            if ($expected_param_count === null) {
+                $this->assertNull($symbol_information);
+            } else {
+                $this->assertNotNull($symbol_information);
+                $this->assertNotNull($symbol_information->parameters);
+                $this->assertCount($expected_param_count, $symbol_information->parameters);
+            }
+        } else {
+            $this->assertNull($reference_location);
+        }
     }
 }