Upgrade C# linter to support linting multiple files at a time

Summary:
This upgrades `cslint` to support linting multiple files at a time.  As this required a backwards-incompatible to `cslint`, I've added a SUPPORTED_VERSION constant which can be used to detect these kinds of breaking changes in the future (and prompt users to upgrade the `cslint` they have in their repository).

The reason for this upgrade is mainly around running `arc lint --everything`, where there are significant performance benefits gained when bulk linting lots of files per command execution.

Test Plan: Upgraded `cslint` in the Tychaia repository and ran `arc lint --everything --trace`.  Saw a substantially less number of executions happening for linting and all of the results came through as expected.

Reviewers: epriestley, #blessed_reviewers

Reviewed By: epriestley

CC: Korvin, epriestley, aran, waynea

Differential Revision: https://secure.phabricator.com/D7599

src/lint/linter/ArcanistCSharpLinter.php

@@ -5,13 +5,16 @@
  *
  * @group linter
  */
-final class ArcanistCSharpLinter extends ArcanistFutureLinter {
+final class ArcanistCSharpLinter extends ArcanistLinter {
 
   private $runtimeEngine;
   private $cslintEngine;
   private $cslintHintPath;
   private $loaded;
   private $discoveryMap;
+  private $futures;
+
+  const SUPPORTED_VERSION = 1;
 
   public function getLinterName() {
     return 'C#';
@@ -101,74 +104,135 @@ final class ArcanistCSharpLinter extends ArcanistFutureLinter {
       throw new Exception("Unable to locate cslint.");
     }
 
+    // Determine cslint version.
+    $ver_future = new ExecFuture(
+      "%C -v",
+      $this->runtimeEngine.$this->cslintEngine);
+    list($err, $stdout, $stderr) = $ver_future->resolve();
+    if ($err !== 0) {
+      throw new Exception(
+        "You are running an old version of cslint.  Please ".
+        "upgrade to version ".self::SUPPORTED_VERSION.".");
+    }
+    $ver = (int)$stdout;
+    if ($ver < self::SUPPORTED_VERSION) {
+      throw new Exception(
+        "You are running an old version of cslint.  Please ".
+        "upgrade to version ".self::SUPPORTED_VERSION.".");
+    } elseif ($ver > self::SUPPORTED_VERSION) {
+      throw new Exception(
+        "Arcanist does not support this version of cslint (it is ".
+        "newer).  You can try upgrading Arcanist with `arc upgrade`.");
+    }
+
     $this->loaded = true;
   }
 
-  protected function buildFutures(array $paths) {
+  public function lintPath($path) {
+  }
+
+  public function willLintPaths(array $paths) {
     $this->loadEnvironment();
 
     $futures = array();
 
+    // Bulk linting up into futures, where the number of files
+    // is based on how long the command is.
+    $current_paths = array();
     foreach ($paths as $path) {
-      // %s won't pass through the JSON correctly
+      // If the current paths for the command, plus the next path
-      // under Windows.  This is probably because not only
+      // is greater than 6000 characters (less than the Windows
-      // does the JSON have quotation marks in the content,
+      // command line limit), then finalize this future and add it.
-      // but because there'll be a lot of escaping and
+      $total = 0;
-      // double escaping because the JSON also contains
+      foreach ($current_paths as $current_path) {
-      // regular expressions.  cslint supports passing the
+        $total += strlen($current_path) + 3; // Quotes and space.
-      // settings JSON through base64-encoded to mitigate
+      }
-      // this issue.
+      if ($total + strlen($path) > 6000) {
-      $futures[$path] = new ExecFuture(
+        // %s won't pass through the JSON correctly
-        "%C --settings-base64=%s -r=. %s",
+        // under Windows.  This is probably because not only
+        // does the JSON have quotation marks in the content,
+        // but because there'll be a lot of escaping and
+        // double escaping because the JSON also contains
+        // regular expressions.  cslint supports passing the
+        // settings JSON through base64-encoded to mitigate
+        // this issue.
+        $futures[] = new ExecFuture(
+          "%C --settings-base64=%s -r=. %Ls",
+          $this->runtimeEngine.$this->cslintEngine,
+          base64_encode(json_encode($this->discoveryMap)),
+          $current_paths);
+        $current_paths = array();
+      }
+
+      // Append the path to the current paths array.
+      $current_paths[] = $this->getEngine()->getFilePathOnDisk($path);
+    }
+
+    // If we still have paths left in current paths, then we need to create
+    // a future for those too.
+    if (count($current_paths) > 0) {
+      $futures[] = new ExecFuture(
+        "%C --settings-base64=%s -r=. %Ls",
         $this->runtimeEngine.$this->cslintEngine,
         base64_encode(json_encode($this->discoveryMap)),
-        $this->getEngine()->getFilePathOnDisk($path));
+        $current_paths);
+      $current_paths = array();
     }
 
-    return $futures;
+    $this->futures = $futures;
   }
 
-  protected function resolveFuture($path, Future $future) {
+  public function didRunLinters() {
-    list($rc, $stdout) = $future->resolve();
+    if ($this->futures) {
-    $results = json_decode($stdout);
+      foreach (Futures($this->futures) as $future) {
-    if ($results === null || $results->Issues === null) {
+        $this->resolveFuture($future);
-      return;
+      }
     }
-    foreach ($results->Issues as $issue) {
+  }
-      $message = new ArcanistLintMessage();
+
-      $message->setPath($path);
+  protected function resolveFuture(Future $future) {
-      $message->setLine($issue->LineNumber);
+    list($stdout) = $future->resolvex();
-      $message->setCode($issue->Index->Code);
+    $all_results = json_decode($stdout);
-      $message->setName($issue->Index->Name);
+    foreach ($all_results as $results) {
-      $message->setChar($issue->Column);
+      if ($results === null || $results->Issues === null) {
-      $message->setOriginalText($issue->OriginalText);
+        return;
-      $message->setReplacementText($issue->ReplacementText);
-      $message->setDescription(
-        vsprintf($issue->Index->Message, $issue->Parameters));
-      $severity = ArcanistLintSeverity::SEVERITY_ADVICE;
-      switch ($issue->Index->Severity) {
-        case 0:
-          $severity = ArcanistLintSeverity::SEVERITY_ADVICE;
-          break;
-        case 1:
-          $severity = ArcanistLintSeverity::SEVERITY_AUTOFIX;
-          break;
-        case 2:
-          $severity = ArcanistLintSeverity::SEVERITY_WARNING;
-          break;
-        case 3:
-          $severity = ArcanistLintSeverity::SEVERITY_ERROR;
-          break;
-        case 4:
-          $severity = ArcanistLintSeverity::SEVERITY_DISABLED;
-          break;
       }
-      $severity_override = $this->getLintMessageSeverity($issue->Index->Code);
+      foreach ($results->Issues as $issue) {
-      if ($severity_override !== null) {
+        $message = new ArcanistLintMessage();
-        $severity = $severity_override;
+        $message->setPath($results->FileName);
+        $message->setLine($issue->LineNumber);
+        $message->setCode($issue->Index->Code);
+        $message->setName($issue->Index->Name);
+        $message->setChar($issue->Column);
+        $message->setOriginalText($issue->OriginalText);
+        $message->setReplacementText($issue->ReplacementText);
+        $message->setDescription(
+          vsprintf($issue->Index->Message, $issue->Parameters));
+        $severity = ArcanistLintSeverity::SEVERITY_ADVICE;
+        switch ($issue->Index->Severity) {
+          case 0:
+            $severity = ArcanistLintSeverity::SEVERITY_ADVICE;
+            break;
+          case 1:
+            $severity = ArcanistLintSeverity::SEVERITY_AUTOFIX;
+            break;
+          case 2:
+            $severity = ArcanistLintSeverity::SEVERITY_WARNING;
+            break;
+          case 3:
+            $severity = ArcanistLintSeverity::SEVERITY_ERROR;
+            break;
+          case 4:
+            $severity = ArcanistLintSeverity::SEVERITY_DISABLED;
+            break;
+        }
+        $severity_override = $this->getLintMessageSeverity($issue->Index->Code);
+        if ($severity_override !== null) {
+          $severity = $severity_override;
+        }
+        $message->setSeverity($severity);
+        $this->addLintMessage($message);
       }
-      $message->setSeverity($severity);
-      $this->addLintMessage($message);
     }
   }