Add error message when psalter asked to work beyond its abilities; allow fixing all issues and output list of fixable issues (#1687)

* Oputput error message when asked to fix non-fixable issue

* Document ability to fix function PossiblyUndefinedGlobalVariable

* Add --issues=all option to fix all possible issues

* Add --list-supported-issues option to psalter

* Fix psalm issues

* Add newline to end of psalter help output

* Adjust messages output from psalter

* Use fwrite(STDERR, instead of die( for issue list related errors in psalter

* Restore missing exits in psalter

docs/fixing_code.md

@@ -36,7 +36,8 @@ The above example plugin converts all unnecessarily qualified classnames in your
 
 ## Supported fixes
 
-This initial release provides support for the following alterations, corresponding to the names of issues Psalm finds:
+This initial release provides support for the following alterations, corresponding to the names of issues Psalm finds.
+To fix all of these at once, run `vendor/bin/psalter --issues=all`
 
 ### MissingReturnType
 
@@ -252,6 +253,34 @@ function foo() : string {
 
 Running `vendor/bin/psalter --issues=PossiblyUndefinedVariable` on
 
+```php
+function foo()
+{
+    if (rand(0, 1)) {
+      $a = 5;
+    }
+    echo $a;
+}
+```
+
+gives
+
+```php
+function foo()
+{
+    $a = null;
+    if (rand(0, 1)) {
+      $a = 5;
+    }
+    echo $a;
+}
+```
+
+
+### PossiblyUndefinedGlobalVariable
+
+Running `vendor/bin/psalter --issues=PossiblyUndefinedGlobalVariable` on
+
 ```php
 if (rand(0, 1)) {
   $a = 5;

src/Psalm/Exception/UnsupportedIssueToFixException.php

@@ -0,0 +1,8 @@
+<?php
+
+namespace Psalm\Exception;
+
+class UnsupportedIssueToFixException extends \Exception
+{
+
+}

src/Psalm/Internal/Analyzer/ProjectAnalyzer.php

@@ -4,15 +4,32 @@ namespace Psalm\Internal\Analyzer;
 use Psalm\Codebase;
 use Psalm\Config;
 use Psalm\Context;
+use Psalm\Exception\UnsupportedIssueToFixException;
 use Psalm\Internal\LanguageServer\{LanguageServer, ProtocolStreamReader, ProtocolStreamWriter};
 use Psalm\Internal\Provider\ClassLikeStorageProvider;
 use Psalm\Internal\Provider\FileProvider;
 use Psalm\Internal\Provider\FileReferenceProvider;
 use Psalm\Internal\Provider\ParserCacheProvider;
 use Psalm\Internal\Provider\Providers;
+use Psalm\Issue\InvalidFalsableReturnType;
+use Psalm\Issue\InvalidNullableReturnType;
+use Psalm\Issue\InvalidReturnType;
+use Psalm\Issue\LessSpecificReturnType;
+use Psalm\Issue\MismatchingDocblockParamType;
+use Psalm\Issue\MismatchingDocblockReturnType;
+use Psalm\Issue\MissingClosureReturnType;
+use Psalm\Issue\MissingParamType;
+use Psalm\Issue\MissingReturnType;
+use Psalm\Issue\PossiblyUndefinedGlobalVariable;
+use Psalm\Issue\PossiblyUndefinedVariable;
+use Psalm\Issue\PossiblyUnusedMethod;
+use Psalm\Issue\PossiblyUnusedProperty;
+use Psalm\Issue\UnusedMethod;
+use Psalm\Issue\UnusedProperty;
 use Psalm\Progress\Progress;
 use Psalm\Progress\VoidProgress;
 use Psalm\Type;
+use Psalm\Issue\CodeIssue;
 
 /**
  * @internal
@@ -156,6 +173,27 @@ class ProjectAnalyzer
         self::TYPE_TEXT,
     ];
 
+    /**
+     * @var array<int, class-string<CodeIssue>>
+     */
+    const SUPPORTED_ISSUES_TO_FIX = [
+        InvalidFalsableReturnType::class,
+        InvalidNullableReturnType::class,
+        InvalidReturnType::class,
+        LessSpecificReturnType::class,
+        MismatchingDocblockParamType::class,
+        MismatchingDocblockReturnType::class,
+        MissingClosureReturnType::class,
+        MissingParamType::class,
+        MissingReturnType::class,
+        PossiblyUndefinedGlobalVariable::class,
+        PossiblyUndefinedVariable::class,
+        PossiblyUnusedMethod::class,
+        PossiblyUnusedProperty::class,
+        UnusedMethod::class,
+        UnusedProperty::class,
+    ];
+
     /**
      * @param bool          $use_color
      * @param bool          $show_info
@@ -795,14 +833,34 @@ class ProjectAnalyzer
 
     /**
      * @param array<string, bool> $issues
+     * @throws UnsupportedIssueToFixException
      *
      * @return void
      */
     public function setIssuesToFix(array $issues)
     {
+        $supported_issues_to_fix = static::getSupportedIssuesToFix();
+
+        $unsupportedIssues = array_diff(array_keys($issues), $supported_issues_to_fix);
+
+        if (! empty($unsupportedIssues)) {
+            throw new UnsupportedIssueToFixException(
+                'Psalm doesn\'t know how to fix issue(s): ' . implode(', ', $unsupportedIssues) . PHP_EOL
+                . 'Supported issues to fix are: ' . implode(',', $supported_issues_to_fix)
+            );
+        }
+
         $this->issues_to_fix = $issues;
     }
 
+    public function setAllIssuesToFix(): void
+    {
+        /** @var array<string, true> $keyed_issues */
+        $keyed_issues = array_fill_keys(static::getSupportedIssuesToFix(), true);
+
+        $this->setIssuesToFix($keyed_issues);
+    }
+
     /**
      * @return array<string, bool>
      *
@@ -954,4 +1012,19 @@ class ProjectAnalyzer
 
         throw new \LogicException('failed to detect number of CPUs!');
     }
+
+    /**
+     * @return array<string>
+     */
+    public static function getSupportedIssuesToFix(): array
+    {
+        return array_map(
+            /** @param class-string $issue_class */
+            function (string $issue_class): string {
+                $parts = explode('\\', $issue_class);
+                return end($parts);
+            },
+            self::SUPPORTED_ISSUES_TO_FIX
+        );
+    }
 }

src/psalter.php

@@ -21,7 +21,7 @@ $args = array_slice($argv, 1);
 $valid_short_options = ['f:', 'm', 'h', 'r:'];
 $valid_long_options = [
     'help', 'debug', 'debug-by-line', 'config:', 'file:', 'root:',
-    'plugin:', 'issues:', 'php-version:', 'dry-run', 'safe-types',
+    'plugin:', 'issues:', 'list-supported-issues', 'php-version:', 'dry-run', 'safe-types',
     'find-unused-code', 'threads:', 'codeowner:',
     'allow-backwards-incompatible-changes:',
 ];
@@ -116,7 +116,11 @@ Options:
     --php-version=PHP_MAJOR_VERSION.PHP_MINOR_VERSION
 
     --issues=IssueType1,IssueType2
-        If any issues can be fixed automatically, Psalm will update the codebase
+        If any issues can be fixed automatically, Psalm will update the codebase. To fix as many issues as possible,
+        use --issues=all
+
+     --list-supported-issues
+        Display the list of issues that psalter knows how to fix
 
     --find-unused-code
         Include unused code as a candidate for removal
@@ -129,14 +133,19 @@ Options:
 
     --allow-backwards-incompatible-changes=BOOL
         Allow Psalm modify method signatures that could break code outside the project. Defaults to true.
+
 HELP;
 
     exit;
 }
 
-if (!isset($options['issues']) && (!isset($options['plugin']) || $options['plugin'] === false)) {
-    die('Please specify the issues you want to fix with --issues=IssueOne,IssueTwo '
-        . 'or provide a plugin that has its own manipulations with --plugin=path/to/plugin.php' . PHP_EOL);
+if (!isset($options['issues']) &&
+    !isset($options['list-supported-issues']) &&
+    (!isset($options['plugin']) || $options['plugin'] === false)
+) {
+    fwrite(STDERR, 'Please specify the issues you want to fix with --issues=IssueOne,IssueTwo or --issues=all, ' .
+        'or provide a plugin that has its own manipulations with --plugin=path/to/plugin.php' . PHP_EOL);
+    exit(1);
 }
 
 if (isset($options['root'])) {
@@ -189,6 +198,11 @@ $providers = new Psalm\Internal\Provider\Providers(
     new Psalm\Internal\Provider\ClassLikeStorageCacheProvider($config)
 );
 
+if (array_key_exists('list-supported-issues', $options)) {
+    echo implode(',', ProjectAnalyzer::getSupportedIssuesToFix()) . PHP_EOL;
+    exit();
+}
+
 $debug = array_key_exists('debug', $options);
 $progress = $debug
     ? new DebugProgress()
@@ -373,7 +387,17 @@ $project_analyzer->alterCodeAfterCompletion(
     array_key_exists('dry-run', $options),
     array_key_exists('safe-types', $options)
 );
-$project_analyzer->setIssuesToFix($keyed_issues);
+
+if ($keyed_issues === ['all' => true]) {
+    $project_analyzer->setAllIssuesToFix();
+} else {
+    try {
+        $project_analyzer->setIssuesToFix($keyed_issues);
+    } catch (\Psalm\Exception\UnsupportedIssueToFixException $e) {
+        fwrite(STDERR, $e->getMessage() . PHP_EOL);
+        exit(1);
+    }
+}
 
 $start_time = microtime(true);