Fix location of function param vars

src/Psalm/Checker/FunctionChecker.php

@@ -301,6 +301,7 @@ class FunctionChecker extends FunctionLikeChecker
                     $by_reference,
                     $param_type,
                     null,
+                    null,
                     $optional,
                     false,
                     $variadic

src/Psalm/Checker/FunctionLikeChecker.php

@@ -42,6 +42,7 @@ abstract class FunctionLikeChecker extends SourceChecker implements StatementsSo
 {
     const RETURN_TYPE_REGEX = '/\\:\s+(\\??[A-Za-z0-9_\\\\\[\]]+)/';
     const PARAM_TYPE_REGEX = '/^(\\??[A-Za-z0-9_\\\\\[\]]+)\s/';
+    const PARAM_TYPE_VAR = '/(\$[^ ]*)/';
 
     /**
      * @var Closure|Function_|ClassMethod
@@ -287,7 +288,7 @@ abstract class FunctionLikeChecker extends SourceChecker implements StatementsSo
             $context->vars_in_scope['$' . $function_param->name] = $param_type;
             $context->vars_possibly_in_scope['$' . $function_param->name] = true;
 
-            if (!$function_param->location) {
+            if (!$function_param->type_location || !$function_param->location) {
                 continue;
             }
 
@@ -309,7 +310,7 @@ abstract class FunctionLikeChecker extends SourceChecker implements StatementsSo
                         new InvalidDocblock(
                             'Parameter $' . $function_param->name . ' has wrong type \'' . $param_type .
                                 '\', should be \'' . $signature_type . '\'',
-                            $function_param->location
+                            $function_param->type_location
                         ),
                         $storage->suppressed_issues
                     )) {
@@ -334,7 +335,7 @@ abstract class FunctionLikeChecker extends SourceChecker implements StatementsSo
                         new InvalidParamDefault(
                             'Default value for argument ' . ($offset + 1) . ' of method ' . $cased_method_id .
                                 ' does not match the given type ' . $param_type,
-                            $function_param->location
+                            $function_param->type_location
                         )
                     )) {
                         // fall through
@@ -346,19 +347,25 @@ abstract class FunctionLikeChecker extends SourceChecker implements StatementsSo
                 $substituted_type = clone $param_type;
                 $generic_types = [];
                 $substituted_type->replaceTemplateTypesWithStandins($template_types, $generic_types, null);
-                $substituted_type->check($this->source, $function_param->location, $this->suppressed_issues, [], false);
+                $substituted_type->check(
+                    $this->source,
+                    $function_param->type_location,
+                    $this->suppressed_issues,
+                    [],
+                    false
+                );
             } else {
-                $param_type->check($this->source, $function_param->location, $this->suppressed_issues, [], false);
+                $param_type->check($this->source, $function_param->type_location, $this->suppressed_issues, [], false);
             }
 
             if ($this->getFileChecker()->project_checker->collect_references) {
-                if ($function_param->location !== $function_param->signature_location &&
-                    $function_param->signature_location &&
+                if ($function_param->type_location !== $function_param->signature_type_location &&
+                    $function_param->signature_type_location &&
                     $function_param->signature_type
                 ) {
                     $function_param->signature_type->check(
                         $this->source,
-                        $function_param->signature_location,
+                        $function_param->signature_type_location,
                         $this->suppressed_issues,
                         [],
                         false
@@ -1281,6 +1288,7 @@ abstract class FunctionLikeChecker extends SourceChecker implements StatementsSo
             (bool)$param->isPassedByReference(),
             $param_type,
             null,
+            null,
             $is_optional,
             $is_nullable,
             $param->isVariadic()

src/Psalm/FunctionLikeParameter.php

@@ -41,7 +41,12 @@ class FunctionLikeParameter
     /**
      * @var CodeLocation|null
      */
-    public $signature_location;
+    public $type_location;
+
+    /**
+     * @var CodeLocation|null
+     */
+    public $signature_type_location;
 
     /**
      * @var bool
@@ -62,6 +67,7 @@ class FunctionLikeParameter
         $by_ref,
         Type\Union $type = null,
         CodeLocation $location = null,
+        CodeLocation $type_location = null,
         $is_optional = true,
         $is_nullable = false,
         $is_variadic = false
@@ -74,6 +80,7 @@ class FunctionLikeParameter
         $this->is_nullable = $is_nullable;
         $this->is_variadic = $is_variadic;
         $this->location = $location;
-        $this->signature_location = $location;
+        $this->type_location = $type_location;
+        $this->signature_type_location = $type_location;
     }
 }

src/Psalm/Visitor/DependencyFinderVisitor.php

@@ -968,7 +968,10 @@ class DependencyFinderVisitor extends PhpParser\NodeVisitorAbstract implements P
             $param->name,
             $param->byRef,
             $param_type,
-            new CodeLocation($this->file_checker, $param, null, false, FunctionLikeChecker::PARAM_TYPE_REGEX),
+            new CodeLocation($this->file_checker, $param, null, false, FunctionLikeChecker::PARAM_TYPE_VAR),
+            $param_typehint
+                ? new CodeLocation($this->file_checker, $param, null, false, FunctionLikeChecker::PARAM_TYPE_REGEX)
+                : null,
             $is_optional,
             $is_nullable,
             $param->variadic
@@ -1067,7 +1070,7 @@ class DependencyFinderVisitor extends PhpParser\NodeVisitorAbstract implements P
                 }
 
                 $storage_param->type = $new_param_type;
-                $storage_param->location = $code_location;
+                $storage_param->type_location = $code_location;
                 continue;
             }
 
@@ -1092,7 +1095,7 @@ class DependencyFinderVisitor extends PhpParser\NodeVisitorAbstract implements P
 
             $storage_param->type = new Type\Union(array_values($improved_atomic_types));
             $storage_param->type->setFromDocblock();
-            $storage_param->location = $code_location;
+            $storage_param->type_location = $code_location;
         }
     }
 

tests/JsonOutputTest.php

@@ -29,6 +29,7 @@ class JsonOutputTest extends TestCase
         $config->throw_exception = false;
         $config->stop_on_first_error = false;
         $this->project_checker->setConfig($config);
+        $this->project_checker->collect_references = true;
     }
 
     /**
@@ -87,6 +88,7 @@ echo $a;';
 
         $file_checker = new FileChecker('somefile.php', $this->project_checker);
         $file_checker->visitAndAnalyzeMethods();
+        $this->project_checker->checkClassReferences();
         $issue_data = IssueBuffer::getIssuesData();
         $this->assertSame(
             [
@@ -132,6 +134,20 @@ echo $a;';
                     'snippet_to' => 84,
                     'column' => 10,
                 ],
+                [
+                    'severity' => 'error',
+                    'line_number' => 2,
+                    'type' => 'UnusedParam',
+                    'message' => 'Param $your_code is never referenced in this method',
+                    'file_name' => 'somefile.php',
+                    'file_path' => 'somefile.php',
+                    'snippet' => 'function psalmCanVerify(int $your_code) : ?string {',
+                    'from' => 34,
+                    'to' => 44,
+                    'snippet_from' => 6,
+                    'snippet_to' => 57,
+                    'column' => 29,
+                ],
                 [
                     'severity' => 'error',
                     'line_number' => 2,