Introduce "arc inspect" and some of the new ref/hardpoint classes

Summary:
Ref T11968. Inches toward the new ref/hardpoint code by introducing the modern refs as "RefPro" objects and supporting an "arc inspect <object>" to load objects and hardpoints.

This doesn't impact any existing runtime behavior.

Test Plan: Ran "arc inspect [--all] commit(...)", got hardpoint queries and yield-based data fetching.

Maniphest Tasks: T11968

Differential Revision: https://secure.phabricator.com/D21078

src/__phutil_library_map__.php

@@ -54,6 +54,7 @@ phutil_register_library_map(array(
     'ArcanistBraceFormattingXHPASTLinterRule' => 'lint/linter/xhpast/rules/ArcanistBraceFormattingXHPASTLinterRule.php',
     'ArcanistBraceFormattingXHPASTLinterRuleTestCase' => 'lint/linter/xhpast/rules/__tests__/ArcanistBraceFormattingXHPASTLinterRuleTestCase.php',
     'ArcanistBranchRef' => 'ref/ArcanistBranchRef.php',
+    'ArcanistBranchRefPro' => 'ref/ArcanistBranchRefPro.php',
     'ArcanistBranchWorkflow' => 'workflow/ArcanistBranchWorkflow.php',
     'ArcanistBrowseCommitHardpointLoader' => 'browse/loader/ArcanistBrowseCommitHardpointLoader.php',
     'ArcanistBrowseCommitURIHardpointLoader' => 'browse/loader/ArcanistBrowseCommitURIHardpointLoader.php',
@@ -102,7 +103,10 @@ phutil_register_library_map(array(
     'ArcanistCommentStyleXHPASTLinterRule' => 'lint/linter/xhpast/rules/ArcanistCommentStyleXHPASTLinterRule.php',
     'ArcanistCommentStyleXHPASTLinterRuleTestCase' => 'lint/linter/xhpast/rules/__tests__/ArcanistCommentStyleXHPASTLinterRuleTestCase.php',
     'ArcanistCommitRef' => 'ref/ArcanistCommitRef.php',
+    'ArcanistCommitRefInspector' => 'inspector/ArcanistCommitRefInspector.php',
+    'ArcanistCommitRefPro' => 'ref/ArcanistCommitRefPro.php',
     'ArcanistCommitUpstreamHardpointLoader' => 'loader/ArcanistCommitUpstreamHardpointLoader.php',
+    'ArcanistCommitUpstreamHardpointQuery' => 'query/ArcanistCommitUpstreamHardpointQuery.php',
     'ArcanistCommitWorkflow' => 'workflow/ArcanistCommitWorkflow.php',
     'ArcanistCompilerLintRenderer' => 'lint/renderer/ArcanistCompilerLintRenderer.php',
     'ArcanistComposerLinter' => 'lint/linter/ArcanistComposerLinter.php',
@@ -203,6 +207,7 @@ phutil_register_library_map(array(
     'ArcanistGetConfigWorkflow' => 'workflow/ArcanistGetConfigWorkflow.php',
     'ArcanistGitAPI' => 'repository/api/ArcanistGitAPI.php',
     'ArcanistGitCommitMessageHardpointLoader' => 'loader/ArcanistGitCommitMessageHardpointLoader.php',
+    'ArcanistGitCommitMessageHardpointQuery' => 'query/ArcanistGitCommitMessageHardpointQuery.php',
     'ArcanistGitHardpointLoader' => 'loader/ArcanistGitHardpointLoader.php',
     'ArcanistGitLandEngine' => 'land/ArcanistGitLandEngine.php',
     'ArcanistGitRevisionHardpointLoader' => 'loader/ArcanistGitRevisionHardpointLoader.php',
@@ -226,6 +231,7 @@ phutil_register_library_map(array(
     'ArcanistHardpointRequest' => 'hardpoint/ArcanistHardpointRequest.php',
     'ArcanistHardpointRequestList' => 'hardpoint/ArcanistHardpointRequestList.php',
     'ArcanistHardpointTask' => 'hardpoint/ArcanistHardpointTask.php',
+    'ArcanistHardpointTaskResult' => 'hardpoint/ArcanistHardpointTaskResult.php',
     'ArcanistHelpWorkflow' => 'toolset/workflow/ArcanistHelpWorkflow.php',
     'ArcanistHexadecimalNumericScalarCasingXHPASTLinterRule' => 'lint/linter/xhpast/rules/ArcanistHexadecimalNumericScalarCasingXHPASTLinterRule.php',
     'ArcanistHexadecimalNumericScalarCasingXHPASTLinterRuleTestCase' => 'lint/linter/xhpast/rules/__tests__/ArcanistHexadecimalNumericScalarCasingXHPASTLinterRuleTestCase.php',
@@ -245,6 +251,7 @@ phutil_register_library_map(array(
     'ArcanistInlineHTMLXHPASTLinterRuleTestCase' => 'lint/linter/xhpast/rules/__tests__/ArcanistInlineHTMLXHPASTLinterRuleTestCase.php',
     'ArcanistInnerFunctionXHPASTLinterRule' => 'lint/linter/xhpast/rules/ArcanistInnerFunctionXHPASTLinterRule.php',
     'ArcanistInnerFunctionXHPASTLinterRuleTestCase' => 'lint/linter/xhpast/rules/__tests__/ArcanistInnerFunctionXHPASTLinterRuleTestCase.php',
+    'ArcanistInspectWorkflow' => 'workflow/ArcanistInspectWorkflow.php',
     'ArcanistInstallCertificateWorkflow' => 'workflow/ArcanistInstallCertificateWorkflow.php',
     'ArcanistInstanceOfOperatorXHPASTLinterRule' => 'lint/linter/xhpast/rules/ArcanistInstanceOfOperatorXHPASTLinterRule.php',
     'ArcanistInstanceofOperatorXHPASTLinterRuleTestCase' => 'lint/linter/xhpast/rules/__tests__/ArcanistInstanceofOperatorXHPASTLinterRuleTestCase.php',
@@ -381,6 +388,8 @@ phutil_register_library_map(array(
     'ArcanistRaggedClassTreeEdgeXHPASTLinterRule' => 'lint/linter/xhpast/rules/ArcanistRaggedClassTreeEdgeXHPASTLinterRule.php',
     'ArcanistRaggedClassTreeEdgeXHPASTLinterRuleTestCase' => 'lint/linter/xhpast/rules/__tests__/ArcanistRaggedClassTreeEdgeXHPASTLinterRuleTestCase.php',
     'ArcanistRef' => 'ref/ArcanistRef.php',
+    'ArcanistRefInspector' => 'inspector/ArcanistRefInspector.php',
+    'ArcanistRefPro' => 'ref/ArcanistRefPro.php',
     'ArcanistRefQuery' => 'ref/ArcanistRefQuery.php',
     'ArcanistRepositoryAPI' => 'repository/api/ArcanistRepositoryAPI.php',
     'ArcanistRepositoryAPIMiscTestCase' => 'repository/api/__tests__/ArcanistRepositoryAPIMiscTestCase.php',
@@ -489,12 +498,15 @@ phutil_register_library_map(array(
     'ArcanistWildConfigOption' => 'config/option/ArcanistWildConfigOption.php',
     'ArcanistWorkflow' => 'workflow/ArcanistWorkflow.php',
     'ArcanistWorkflowArgument' => 'toolset/ArcanistWorkflowArgument.php',
+    'ArcanistWorkflowHardpointQuery' => 'toolset/query/ArcanistWorkflowHardpointQuery.php',
     'ArcanistWorkflowInformation' => 'toolset/ArcanistWorkflowInformation.php',
     'ArcanistWorkingCopy' => 'workingcopy/ArcanistWorkingCopy.php',
+    'ArcanistWorkingCopyCommitHardpointQuery' => 'query/ArcanistWorkingCopyCommitHardpointQuery.php',
     'ArcanistWorkingCopyConfigurationSource' => 'config/source/ArcanistWorkingCopyConfigurationSource.php',
     'ArcanistWorkingCopyIdentity' => 'workingcopyidentity/ArcanistWorkingCopyIdentity.php',
     'ArcanistWorkingCopyPath' => 'workingcopy/ArcanistWorkingCopyPath.php',
     'ArcanistWorkingCopyStateRef' => 'ref/ArcanistWorkingCopyStateRef.php',
+    'ArcanistWorkingCopyStateRefPro' => 'ref/ArcanistWorkingCopyStateRefPro.php',
     'ArcanistXHPASTLintNamingHook' => 'lint/linter/xhpast/ArcanistXHPASTLintNamingHook.php',
     'ArcanistXHPASTLintNamingHookTestCase' => 'lint/linter/xhpast/__tests__/ArcanistXHPASTLintNamingHookTestCase.php',
     'ArcanistXHPASTLintSwitchHook' => 'lint/linter/xhpast/ArcanistXHPASTLintSwitchHook.php',
@@ -1010,6 +1022,7 @@ phutil_register_library_map(array(
     'ArcanistBraceFormattingXHPASTLinterRule' => 'ArcanistXHPASTLinterRule',
     'ArcanistBraceFormattingXHPASTLinterRuleTestCase' => 'ArcanistXHPASTLinterRuleTestCase',
     'ArcanistBranchRef' => 'ArcanistRef',
+    'ArcanistBranchRefPro' => 'ArcanistRefPro',
     'ArcanistBranchWorkflow' => 'ArcanistFeatureWorkflow',
     'ArcanistBrowseCommitHardpointLoader' => 'ArcanistHardpointLoader',
     'ArcanistBrowseCommitURIHardpointLoader' => 'ArcanistBrowseURIHardpointLoader',
@@ -1058,7 +1071,10 @@ phutil_register_library_map(array(
     'ArcanistCommentStyleXHPASTLinterRule' => 'ArcanistXHPASTLinterRule',
     'ArcanistCommentStyleXHPASTLinterRuleTestCase' => 'ArcanistXHPASTLinterRuleTestCase',
     'ArcanistCommitRef' => 'ArcanistRef',
+    'ArcanistCommitRefInspector' => 'ArcanistRefInspector',
+    'ArcanistCommitRefPro' => 'ArcanistRefPro',
     'ArcanistCommitUpstreamHardpointLoader' => 'ArcanistHardpointLoader',
+    'ArcanistCommitUpstreamHardpointQuery' => 'ArcanistWorkflowHardpointQuery',
     'ArcanistCommitWorkflow' => 'ArcanistWorkflow',
     'ArcanistCompilerLintRenderer' => 'ArcanistLintRenderer',
     'ArcanistComposerLinter' => 'ArcanistLinter',
@@ -1159,6 +1175,7 @@ phutil_register_library_map(array(
     'ArcanistGetConfigWorkflow' => 'ArcanistWorkflow',
     'ArcanistGitAPI' => 'ArcanistRepositoryAPI',
     'ArcanistGitCommitMessageHardpointLoader' => 'ArcanistGitHardpointLoader',
+    'ArcanistGitCommitMessageHardpointQuery' => 'ArcanistWorkflowHardpointQuery',
     'ArcanistGitHardpointLoader' => 'ArcanistHardpointLoader',
     'ArcanistGitLandEngine' => 'ArcanistLandEngine',
     'ArcanistGitRevisionHardpointLoader' => 'ArcanistGitHardpointLoader',
@@ -1182,6 +1199,7 @@ phutil_register_library_map(array(
     'ArcanistHardpointRequest' => 'Phobject',
     'ArcanistHardpointRequestList' => 'Phobject',
     'ArcanistHardpointTask' => 'Phobject',
+    'ArcanistHardpointTaskResult' => 'Phobject',
     'ArcanistHelpWorkflow' => 'ArcanistWorkflow',
     'ArcanistHexadecimalNumericScalarCasingXHPASTLinterRule' => 'ArcanistXHPASTLinterRule',
     'ArcanistHexadecimalNumericScalarCasingXHPASTLinterRuleTestCase' => 'ArcanistXHPASTLinterRuleTestCase',
@@ -1201,6 +1219,7 @@ phutil_register_library_map(array(
     'ArcanistInlineHTMLXHPASTLinterRuleTestCase' => 'ArcanistXHPASTLinterRuleTestCase',
     'ArcanistInnerFunctionXHPASTLinterRule' => 'ArcanistXHPASTLinterRule',
     'ArcanistInnerFunctionXHPASTLinterRuleTestCase' => 'ArcanistXHPASTLinterRuleTestCase',
+    'ArcanistInspectWorkflow' => 'ArcanistArcWorkflow',
     'ArcanistInstallCertificateWorkflow' => 'ArcanistWorkflow',
     'ArcanistInstanceOfOperatorXHPASTLinterRule' => 'ArcanistXHPASTLinterRule',
     'ArcanistInstanceofOperatorXHPASTLinterRuleTestCase' => 'ArcanistXHPASTLinterRuleTestCase',
@@ -1337,6 +1356,8 @@ phutil_register_library_map(array(
     'ArcanistRaggedClassTreeEdgeXHPASTLinterRule' => 'ArcanistXHPASTLinterRule',
     'ArcanistRaggedClassTreeEdgeXHPASTLinterRuleTestCase' => 'ArcanistXHPASTLinterRuleTestCase',
     'ArcanistRef' => 'Phobject',
+    'ArcanistRefInspector' => 'Phobject',
+    'ArcanistRefPro' => 'ArcanistHardpointObject',
     'ArcanistRefQuery' => 'Phobject',
     'ArcanistRepositoryAPI' => 'Phobject',
     'ArcanistRepositoryAPIMiscTestCase' => 'PhutilTestCase',
@@ -1444,12 +1465,15 @@ phutil_register_library_map(array(
     'ArcanistWildConfigOption' => 'ArcanistConfigOption',
     'ArcanistWorkflow' => 'Phobject',
     'ArcanistWorkflowArgument' => 'Phobject',
+    'ArcanistWorkflowHardpointQuery' => 'ArcanistHardpointQuery',
     'ArcanistWorkflowInformation' => 'Phobject',
     'ArcanistWorkingCopy' => 'Phobject',
+    'ArcanistWorkingCopyCommitHardpointQuery' => 'ArcanistWorkflowHardpointQuery',
     'ArcanistWorkingCopyConfigurationSource' => 'ArcanistFilesystemConfigurationSource',
     'ArcanistWorkingCopyIdentity' => 'Phobject',
     'ArcanistWorkingCopyPath' => 'Phobject',
     'ArcanistWorkingCopyStateRef' => 'ArcanistRef',
+    'ArcanistWorkingCopyStateRefPro' => 'ArcanistRefPro',
     'ArcanistXHPASTLintNamingHook' => 'Phobject',
     'ArcanistXHPASTLintNamingHookTestCase' => 'PhutilTestCase',
     'ArcanistXHPASTLintSwitchHook' => 'Phobject',

src/hardpoint/ArcanistHardpointList.php

@@ -46,6 +46,10 @@ final class ArcanistHardpointList
     return isset($this->attached[$hardpoint]);
   }
 
+  public function getHardpoints() {
+    return $this->hardpoints;
+  }
+
   public function getHardpointDefinition($object, $hardpoint) {
     if (!$this->hasHardpoint($object, $hardpoint)) {
       throw new Exception(

src/hardpoint/ArcanistHardpointTask.php

@@ -100,6 +100,7 @@ final class ArcanistHardpointTask
         $generator->next();
       }
 
+      $generator_result = null;
       if ($generator->valid()) {
         $result = $generator->current();
 
@@ -152,17 +153,25 @@ final class ArcanistHardpointTask
           return true;
         }
 
-        throw new Exception(
-          pht(
-            'Hardpoint generator (for query "%s") yielded an unexpected '.
-            'value. Generators may only yield "Future" or '.
-            '"ArcanistHardpointRequest" objects, got "%s".',
-            get_class($query),
-            phutil_describe_type($result)));
+        if ($result instanceof ArcanistHardpointTaskResult) {
+          $generator_result = $result;
+        } else {
+          throw new Exception(
+            pht(
+              'Hardpoint generator (for query "%s") yielded an unexpected '.
+              'value (of type "%s").',
+              get_class($query),
+              phutil_describe_type($result)));
+        }
       }
 
       $this->generator = null;
-      $result = $generator->getReturn();
+
+      if ($generator_result !== null) {
+        $result = $generator_result->getValue();
+      } else {
+        $result = $generator->getReturn();
+      }
 
       $this->attachResult($result);
 

src/hardpoint/ArcanistHardpointTaskResult.php

@@ -0,0 +1,16 @@
+<?php
+
+final class ArcanistHardpointTaskResult
+  extends Phobject {
+
+  private $value;
+
+  public function __construct($value) {
+    $this->value = $value;
+  }
+
+  public function getValue() {
+    return $this->value;
+  }
+
+}

src/inspector/ArcanistCommitRefInspector.php

@@ -0,0 +1,22 @@
+<?php
+
+final class ArcanistCommitRefInspector
+  extends ArcanistRefInspector {
+
+  public function getInspectFunctionName() {
+    return 'commit';
+  }
+
+  public function newInspectRef(array $argv) {
+    if (count($argv) !== 1) {
+      throw new PhutilArgumentUsageException(
+        pht(
+          'Expected exactly one argument to "commit(...)" with a '.
+          'commit hash.'));
+    }
+
+    return id(new ArcanistCommitRefPro())
+      ->setCommitHash($argv[0]);
+  }
+
+}

src/inspector/ArcanistRefInspector.php

@@ -0,0 +1,16 @@
+<?php
+
+abstract class ArcanistRefInspector
+  extends Phobject {
+
+  abstract public function getInspectFunctionName();
+  abstract public function newInspectRef(array $argv);
+
+  final public static function getAllInspectors() {
+    return id(new PhutilClassMapQuery())
+      ->setAncestorClass(__CLASS__)
+      ->setUniqueMethod('getInspectFunctionName')
+      ->execute();
+  }
+
+}

src/query/ArcanistCommitUpstreamHardpointQuery.php

@@ -0,0 +1,53 @@
+<?php
+
+final class ArcanistCommitUpstreamHardpointQuery
+  extends ArcanistWorkflowHardpointQuery {
+
+  public function getHardpoints() {
+    return array(
+      ArcanistCommitRefPro::HARDPOINT_UPSTREAM,
+    );
+  }
+
+  protected function canLoadRef(ArcanistRefPro $ref) {
+    return ($ref instanceof ArcanistCommitRefPro);
+  }
+
+  public function loadHardpoint(array $refs, $hardpoint) {
+    $repository_ref = (yield $this->yieldRepositoryRef());
+    if (!$repository_ref) {
+      yield $this->yieldValue($refs, null);
+    }
+    $repository_phid = $repository_ref->getPHID();
+
+    $commit_map = array();
+    foreach ($refs as $key => $ref) {
+      $hash = $ref->getCommitHash();
+      $commit_map[$hash][] = $key;
+    }
+
+    $commit_info = (yield $this->yieldConduit(
+      'diffusion.querycommits',
+      array(
+        'repositoryPHID' => $repository_phid,
+        'names' => array_keys($commit_map),
+      )));
+
+    $results = array();
+    foreach ($commit_map as $hash => $keys) {
+      $commit_phid = idx($commit_info['identifierMap'], $hash);
+      if ($commit_phid) {
+        $commit_data = idx($commit_info['data'], $commit_phid);
+      } else {
+        $commit_data = null;
+      }
+
+      foreach ($keys as $key) {
+        $results[$key] = $commit_data;
+      }
+    }
+
+    yield $this->yieldMap($results);
+  }
+
+}

src/query/ArcanistGitCommitMessageHardpointQuery.php

@@ -0,0 +1,53 @@
+<?php
+
+final class ArcanistGitCommitMessageHardpointQuery
+  extends ArcanistWorkflowHardpointQuery {
+
+  public function getHardpoints() {
+    return array(
+      ArcanistCommitRefPro::HARDPOINT_MESSAGE,
+    );
+  }
+
+  protected function canLoadRef(ArcanistRefPro $ref) {
+    return ($ref instanceof ArcanistCommitRefPro);
+  }
+
+  protected function canLoadHardpoint() {
+    $api = $this->getRepositoryAPI();
+    return ($api instanceof ArcanistGitAPI);
+  }
+
+  public function loadHardpoint(array $refs, $hardpoint) {
+    $api = $this->getRepositoryAPI();
+
+    $hashes = mpull($refs, 'getCommitHash');
+    $unique_hashes = array_fuse($hashes);
+
+    // TODO: Update this to use "%B", see T5028. We can also bulk-resolve
+    // these with "git show --quiet --format=... hash hash hash ... --".
+
+    $futures = array();
+    foreach ($unique_hashes as $hash) {
+      $futures[$hash] = $api->execFutureLocal(
+        'log -n1 --format=%s %s --',
+        '%s%n%n%b',
+        $hash);
+    }
+
+    yield $this->yieldFutures($futures);
+
+    $messages = array();
+    foreach ($futures as $hash => $future) {
+      list($stdout) = $future->resolvex();
+      $messages[$hash] = $stdout;
+    }
+
+    foreach ($hashes as $ref_key => $hash) {
+      $hashes[$ref_key] = $messages[$hash];
+    }
+
+    yield $this->yieldMap($hashes);
+  }
+
+}

src/query/ArcanistWorkingCopyCommitHardpointQuery.php

@@ -0,0 +1,39 @@
+<?php
+
+final class ArcanistWorkingCopyCommitHardpointQuery
+  extends ArcanistWorkflowHardpointQuery {
+
+  public function getHardpoints() {
+    return array(
+      ArcanistWorkingCopyStateRefPro::HARDPOINT_COMMITREF,
+    );
+  }
+
+  protected function canLoadRef(ArcanistRefPro $ref) {
+    return ($ref instanceof ArcanistWorkingCopyStateRefPro);
+  }
+
+  public function loadHardpoint(array $refs, $hardpoint) {
+    yield $this->yieldRequests(
+      $refs,
+      array(
+        ArcanistWorkingCopyStateRefPro::HARDPOINT_BRANCHREF,
+      ));
+
+    $branch_refs = mpull($refs, 'getBranchRef');
+
+    yield $this->yieldRequests(
+      $branch_refs,
+      array(
+        ArcanistBranchRefPro::HARDPOINT_COMMITREF,
+      ));
+
+    $results = array();
+    foreach ($refs as $key => $ref) {
+      $results[$key] = $ref->getBranchRef()->getCommitRef();
+    }
+
+    yield $this->yieldMap($results);
+  }
+
+}

src/ref/ArcanistBranchRefPro.php

@@ -0,0 +1,57 @@
+<?php
+
+final class ArcanistBranchRefPro
+  extends ArcanistRefPro {
+
+  const HARDPOINT_COMMITREF = 'commitRef';
+
+  private $branchName;
+  private $refName;
+  private $isCurrentBranch;
+
+  public function getRefDisplayName() {
+    return pht('Branch %s', $this->getBranchName());
+  }
+
+  protected function newHardpoints() {
+    return array(
+      $this->newHardpoint(self::HARDPOINT_COMMITREF),
+    );
+  }
+
+  public function setBranchName($branch_name) {
+    $this->branchName = $branch_name;
+    return $this;
+  }
+
+  public function getBranchName() {
+    return $this->branchName;
+  }
+
+  public function setRefName($ref_name) {
+    $this->refName = $ref_name;
+    return $this;
+  }
+
+  public function getRefName() {
+    return $this->refName;
+  }
+
+  public function setIsCurrentBranch($is_current_branch) {
+    $this->isCurrentBranch = $is_current_branch;
+    return $this;
+  }
+
+  public function getIsCurrentBranch() {
+    return $this->isCurrentBranch;
+  }
+
+  public function attachCommitRef(ArcanistCommitRef $ref) {
+    return $this->attachHardpoint(self::HARDPOINT_COMMITREF, $ref);
+  }
+
+  public function getCommitRef() {
+    return $this->getHardpoint(self::HARDPOINT_COMMITREF);
+  }
+
+}

src/ref/ArcanistCommitRefPro.php

@@ -0,0 +1,93 @@
+<?php
+
+final class ArcanistCommitRefPro
+  extends ArcanistRefPro {
+
+  private $commitHash;
+  private $treeHash;
+  private $commitEpoch;
+  private $authorEpoch;
+  private $upstream;
+
+  const HARDPOINT_MESSAGE = 'message';
+  const HARDPOINT_UPSTREAM = 'upstream';
+
+  public function getRefDisplayName() {
+    return pht('Commit "%s"', $this->getCommitHash());
+  }
+
+  protected function newHardpoints() {
+    return array(
+      $this->newHardpoint(self::HARDPOINT_MESSAGE),
+      $this->newHardpoint(self::HARDPOINT_UPSTREAM),
+    );
+  }
+
+  public function setCommitHash($commit_hash) {
+    $this->commitHash = $commit_hash;
+    return $this;
+  }
+
+  public function getCommitHash() {
+    return $this->commitHash;
+  }
+
+  public function setTreeHash($tree_hash) {
+    $this->treeHash = $tree_hash;
+    return $this;
+  }
+
+  public function getTreeHash() {
+    return $this->treeHash;
+  }
+
+  public function setCommitEpoch($commit_epoch) {
+    $this->commitEpoch = $commit_epoch;
+    return $this;
+  }
+
+  public function getCommitEpoch() {
+    return $this->commitEpoch;
+  }
+
+  public function setAuthorEpoch($author_epoch) {
+    $this->authorEpoch = $author_epoch;
+    return $this;
+  }
+
+  public function getAuthorEpoch() {
+    return $this->authorEpoch;
+  }
+
+  public function getSummary() {
+    $message = $this->getMessage();
+
+    $message = trim($message);
+    $lines = phutil_split_lines($message, false);
+
+    return head($lines);
+  }
+
+  public function attachMessage($message) {
+    return $this->attachHardpoint(self::HARDPOINT_MESSAGE, $message);
+  }
+
+  public function getMessage() {
+    return $this->getHardpoint(self::HARDPOINT_MESSAGE);
+  }
+
+  public function getURI() {
+    return $this->getUpstreamProperty('uri');
+  }
+
+  private function getUpstreamProperty($key, $default = null) {
+    $upstream = $this->getHardpoint(self::HARDPOINT_UPSTREAM);
+
+    if (!$upstream) {
+      return $default;
+    }
+
+    return idx($upstream, $key, $default);
+  }
+
+}

src/ref/ArcanistRefPro.php

@@ -0,0 +1,8 @@
+<?php
+
+abstract class ArcanistRefPro
+  extends ArcanistHardpointObject {
+
+  abstract public function getRefDisplayName();
+
+}

src/ref/ArcanistWorkingCopyStateRefPro.php

@@ -0,0 +1,62 @@
+<?php
+
+final class ArcanistWorkingCopyStateRefPro
+  extends ArcanistRefPro {
+
+  const HARDPOINT_COMMITREF = 'commitRef';
+  const HARDPOINT_BRANCHREF = 'branchRef';
+  const HARDPOINT_REVISIONREFS = 'revisionRefs';
+
+  public function getRefDisplayName() {
+    // TODO: This could check attached hardpoints and render something more
+    // insightful.
+    return pht('Working Copy State');
+  }
+
+  protected function newHardpoints() {
+    return array(
+      $this->newHardpoint(self::HARDPOINT_COMMITREF),
+      $this->newHardpoint(self::HARDPOINT_BRANCHREF),
+      $this->newVectorHardpoint(self::HARDPOINT_REVISIONREFS),
+    );
+  }
+
+  public function attachBranchRef(ArcanistBranchRef $branch_ref) {
+    return $this->attachHardpoint(self::HARDPOINT_BRANCHREF, $branch_ref);
+  }
+
+  public function getBranchRef() {
+    return $this->getHardpoint(self::HARDPOINT_BRANCHREF);
+  }
+
+  public function setCommitRef(ArcanistCommitRef $commit_ref) {
+    return $this->attachHardpoint(self::HARDPOINT_COMMITREF, $commit_ref);
+  }
+
+  public function getCommitRef() {
+    return $this->getHardpoint(self::HARDPOINT_COMMITREF);
+  }
+
+  public function getRevisionRefs() {
+    return $this->getHardpoint(self::HARDPOINT_REVISIONREFS);
+  }
+
+  public function getRevisionRef() {
+    if ($this->hasAmbiguousRevisionRefs()) {
+      throw new Exception(
+        pht('State has multiple ambiguous revisions refs.'));
+    }
+
+    $refs = $this->getRevisionRefs();
+    if ($refs) {
+      return head($refs);
+    }
+
+    return null;
+  }
+
+  public function hasAmbiguousRevisionRefs() {
+    return (count($this->getRevisionRefs()) > 1);
+  }
+
+}

src/repository/api/ArcanistFilesystemAPI.php

@@ -82,7 +82,7 @@ final class ArcanistFilesystemAPI
   }
 
   public function getRemoteURI() {
-    throw new PhutilMethodNotImplementedException();
+    return null;
   }
 
   public function supportsLocalCommits() {
@@ -90,7 +90,9 @@ final class ArcanistFilesystemAPI
   }
 
   protected function buildLocalFuture(array $argv) {
-    throw new PhutilMethodNotImplementedException();
+    $future = newv('ExecFuture', $argv);
+    $future->setCWD($this->getPath());
+    return $future;
   }
 
   public function supportsCommitRanges() {

src/toolset/query/ArcanistWorkflowHardpointQuery.php

@@ -0,0 +1,88 @@
+<?php
+
+abstract class ArcanistWorkflowHardpointQuery
+  extends ArcanistHardpointQuery {
+
+  private $workflow;
+  private $canLoadHardpoint;
+
+  final public function setWorkflow(ArcanistWorkflow $workflow) {
+    $this->workflow = $workflow;
+    return $this;
+  }
+
+  final public function getWorkflow() {
+    return $this->workflow;
+  }
+
+  final public function getWorkingCopy() {
+    return $this->getWorkflow()->getWorkingCopy();
+  }
+
+  final public function getRepositoryAPI() {
+    return $this->getWorkingCopy()->getRepositoryAPI();
+  }
+
+  public static function getAllQueries() {
+    return id(new PhutilClassMapQuery())
+      ->setAncestorClass(__CLASS__)
+      ->execute();
+  }
+
+  final public function canLoadObject(ArcanistHardpointObject $object) {
+    if ($this->canLoadHardpoint === null) {
+      $this->canLoadHardpoint = $this->canLoadHardpoint();
+    }
+
+    if (!$this->canLoadHardpoint) {
+      return false;
+    }
+
+    if (!$object instanceof ArcanistRefPro) {
+      return false;
+    }
+
+    return $this->canLoadRef($object);
+  }
+
+  protected function canLoadHardpoint() {
+    return true;
+  }
+
+  abstract protected function canLoadRef(ArcanistRefPro $ref);
+
+  final public function yieldConduit($method, array $parameters) {
+    $conduit_engine = $this->getWorkflow()
+      ->getConduitEngine();
+
+    $call_object = $conduit_engine->newCall($method, $parameters);
+    $call_future = $conduit_engine->newFuture($call_object);
+
+    return $this->yieldFuture($call_future);
+  }
+
+  final public function yieldRepositoryRef() {
+    $workflow = $this->getWorkflow();
+
+    // TODO: This is currently a blocking request, but should yield to the
+    // hardpoint engine in the future.
+
+    $repository_ref = $workflow->getRepositoryRef();
+    $ref_future = new ImmediateFuture($repository_ref);
+
+    return $this->yieldFuture($ref_future);
+  }
+
+  final public function yieldValue(array $refs, $value) {
+    assert_instances_of($refs, 'ArcanistRefPro');
+
+    $keys = array_keys($refs);
+    $map = array_fill_keys($keys, $value);
+    return $this->yieldMap($map);
+  }
+
+  final public function yieldMap(array $map) {
+    return new ArcanistHardpointTaskResult($map);
+  }
+
+}

src/workflow/ArcanistInspectWorkflow.php

@@ -0,0 +1,207 @@
+<?php
+
+final class ArcanistInspectWorkflow
+  extends ArcanistArcWorkflow {
+
+  public function getWorkflowName() {
+    return 'inspect';
+  }
+
+  public function getWorkflowInformation() {
+    $help = pht(<<<EOTEXT
+Inspect internal object properties.
+EOTEXT
+);
+
+    return $this->newWorkflowInformation()
+      ->setSynopsis(pht('Show internal object information.'))
+      ->addExample(pht('**inspect** [__options__] -- __object__'))
+      ->setHelp($help);
+  }
+
+  public function getWorkflowArguments() {
+    return array(
+      $this->newWorkflowArgument('all')
+        ->setHelp(pht('Load all object hardpoints.')),
+      $this->newWorkflowArgument('objects')
+        ->setWildcard(true),
+    );
+  }
+
+  public function runWorkflow() {
+    $is_all = $this->getArgument('all');
+    $objects = $this->getArgument('objects');
+
+    $inspectors = ArcanistRefInspector::getAllInspectors();
+
+    if (!$objects) {
+      echo tsprintf(
+        "%s\n\n",
+        pht('Choose an object to inspect:'));
+
+      foreach ($inspectors as $inspector) {
+        echo tsprintf(
+          "    - %s\n",
+          $inspector->getInspectFunctionName());
+      }
+
+      echo tsprintf("\n");
+
+      return 0;
+    }
+
+    $all_refs = array();
+    $ref_lists = array();
+    foreach ($objects as $description) {
+      $matches = null;
+      if (!preg_match('/^(\w+)(?:\(([^)]+)\))?\z/', $description, $matches)) {
+        throw new PhutilArgumentUsageException(
+          pht(
+            'Object specification "%s" is unknown, expected a specification '.
+            'like "commit(HEAD)".'));
+      }
+
+      $function = $matches[1];
+
+      if (!isset($inspectors[$function])) {
+        ksort($inspectors);
+        throw new PhutilArgumentUsageException(
+          pht(
+            'Unknown object type "%s", supported types are: %s.',
+            $function,
+            implode(', ', array_keys($inspectors))));
+      }
+
+      $inspector = $inspectors[$function];
+
+      if (isset($matches[2])) {
+        $arguments = array($matches[2]);
+      } else {
+        $arguments = array();
+      }
+
+      $ref = $inspector->newInspectRef($arguments);
+
+      $ref_lists[get_class($ref)][] = $ref;
+      $all_refs[] = $ref;
+    }
+
+    if ($is_all) {
+      foreach ($ref_lists as $ref_class => $refs) {
+        $ref = head($refs);
+
+        $hardpoint_list = $ref->getHardpointList();
+        $hardpoints = $hardpoint_list->getHardpoints();
+
+        if ($hardpoints) {
+          $hardpoint_keys = mpull($hardpoints, 'getHardpointKey');
+
+          $this->loadHardpoints(
+            $refs,
+            $hardpoint_keys);
+        }
+      }
+    }
+
+    $list = array();
+    foreach ($all_refs as $ref) {
+      $out = $this->describeRef($ref, 0);
+      $list[] = implode('', $out);
+    }
+    $list = implode("\n", $list);
+
+    echo tsprintf('%B', $list);
+
+    return 0;
+  }
+
+  private function describeRef(ArcanistRefPro $ref, $depth) {
+    $indent = str_repeat(' ', $depth);
+
+    $out = array();
+    $out[] = tsprintf(
+      "%s+ [%s] %s\n",
+      $indent,
+      get_class($ref),
+      $ref->getRefDisplayName());
+
+    $hardpoint_list = $ref->getHardpointList();
+    foreach ($hardpoint_list->getHardpoints() as $hardpoint) {
+      $lines = $this->describeHardpoint($ref, $hardpoint, $depth + 1);
+      foreach ($lines as $line) {
+        $out[] = $line;
+      }
+    }
+
+    return $out;
+  }
+
+  private function describeHardpoint(
+    ArcanistRefPro $ref,
+    ArcanistHardpoint $hardpoint,
+    $depth) {
+    $indent = str_repeat(' ', $depth);
+
+    $children = array();
+    $values = array();
+
+    $hardpoint_key = $hardpoint->getHardpointKey();
+    if ($ref->hasAttachedHardpoint($hardpoint_key)) {
+      $mode = '*';
+      $value = $ref->getHardpoint($hardpoint_key);
+      if ($value instanceof ArcanistRefPro) {
+        $children[] = $value;
+      } else {
+        $values[] = $value;
+      }
+    } else {
+      $mode = 'o';
+    }
+
+    $out = array();
+    $out[] = tsprintf(
+      "%s%s [%s] %s\n",
+      $indent,
+      $mode,
+      get_class($hardpoint),
+      $hardpoint->getHardpointKey());
+
+    foreach ($children as $child) {
+      $lines = $this->describeRef($child, $depth + 1);
+      foreach ($lines as $line) {
+        $out[] = $line;
+      }
+    }
+
+    foreach ($values as $value) {
+      $lines = $this->describeValue($value, $depth + 1);
+      foreach ($lines as $line) {
+        $out[] = $line;
+      }
+    }
+
+    return $out;
+  }
+
+  private function describeValue($value, $depth) {
+    $indent = str_repeat(' ', $depth);
+
+    if (is_string($value)) {
+      $display_value = '"'.addcslashes(substr($value, 0, 64), "\n\r\t\\\"").'"';
+    } else if (is_scalar($value)) {
+      $display_value = phutil_string_cast($value);
+    } else if ($value === null) {
+      $display_value = 'null';
+    } else {
+      $display_value = phutil_describe_type($value);
+    }
+
+    $out = array();
+    $out[] = tsprintf(
+      "%s> %s\n",
+      $indent,
+      $display_value);
+    return $out;
+  }
+
+}

src/workflow/ArcanistWorkflow.php

@@ -76,6 +76,8 @@ abstract class ArcanistWorkflow extends Phobject {
   private $configurationEngine;
   private $configurationSourceList;
 
+  private $hardpointEngine;
+
   final public function setToolset(ArcanistToolset $toolset) {
     $this->toolset = $toolset;
     return $this;
@@ -2329,4 +2331,40 @@ abstract class ArcanistWorkflow extends Phobject {
       ->setExecutableFuture($future);
   }
 
+  final protected function loadHardpoints(
+    array $objects,
+    array $requests) {
+
+    $engine = $this->getHardpointEngine();
+
+    $requests = $engine->requestHardpoints(
+      $objects,
+      $requests);
+
+    // TODO: Wait for only the required requests.
+    $engine->waitForRequests(array());
+  }
+
+  private function getHardpointEngine() {
+    if ($this->hardpointEngine === null) {
+      $this->hardpointEngine = $this->newHardpointEngine();
+    }
+    return $this->hardpointEngine;
+  }
+
+  private function newHardpointEngine() {
+    $engine = new ArcanistHardpointEngine();
+
+    $queries = ArcanistWorkflowHardpointQuery::getAllQueries();
+
+    foreach ($queries as $key => $query) {
+      $queries[$key] = id(clone $query)
+        ->setWorkflow($this);
+    }
+
+    $engine->setQueries($queries);
+
+    return $engine;
+  }
+
 }

src/workingcopy/ArcanistFilesystemWorkingCopy.php

@@ -14,7 +14,7 @@ final class ArcanistFilesystemWorkingCopy
   }
 
   protected function newRepositoryAPI() {
-    return new ArcanistFilesystemAPI();
+    return new ArcanistFilesystemAPI($this->getPath());
   }
 
   public function getProjectConfigurationFilePath() {

src/workingcopy/ArcanistWorkingCopy.php

@@ -57,7 +57,7 @@ abstract class ArcanistWorkingCopy
 
     $working_copy = new ArcanistFilesystemWorkingCopy();
 
-    self::configureWorkingCopy($working_copy, $ancestor_path, $path);
+    self::configureWorkingCopy($working_copy, $path, $path);
 
     return $working_copy;
   }