diff --git a/src/filesystem/binary/PhutilMercurialBinaryAnalyzer.php b/src/filesystem/binary/PhutilMercurialBinaryAnalyzer.php
index 02dbde02..5dbe289d 100644
--- a/src/filesystem/binary/PhutilMercurialBinaryAnalyzer.php
+++ b/src/filesystem/binary/PhutilMercurialBinaryAnalyzer.php
@@ -7,6 +7,8 @@ final class PhutilMercurialBinaryAnalyzer
 
   const CAPABILITY_FILES = 'files';
   const CAPABILITY_INJECTION = 'injection';
+  const CAPABILITY_TEMPLATE_PNODE = 'template_pnode';
+  const CAPABILTIY_ANNOTATE_TEMPLATES = 'annotate_templates';
 
   protected function newBinaryVersion() {
     $future = id(new ExecFuture('hg --version --quiet'))
@@ -60,6 +62,33 @@ final class PhutilMercurialBinaryAnalyzer
       self::CAPABILITY_INJECTION);
   }
 
+  /**
+   * When using `--template` the format for accessing individual parents
+   * changed from `{p1node}` to `{p1.node}` in Mercurial 4.9.
+   *
+   * @return boolean  True if the version of Mercurial is new enough to support
+   *   the `{p1.node}` format in templates, or false if otherwise.
+   */
+  public function isMercurialTemplatePnodeAvailable() {
+    return self::versionHasCapability(
+      $this->requireBinaryVersion(),
+      self::CAPABILITY_TEMPLATE_PNODE);
+  }
+
+  /**
+   * The `hg annotate` command did not accept the `--template` argument until
+   * version 4.6. It appears to function in version 4.5 however it's not
+   * documented and wasn't announced until the 4.6 release.
+   *
+   * @return boolean  True if the version of Mercurial is new enough to support
+   *   the `--template` option when using `hg annotate`, or false if otherwise.
+   */
+  public function isMercurialAnnotateTemplatesAvailable() {
+    return self::versionHasCapability(
+      $this->requireBinaryVersion(),
+      self::CAPABILTIY_ANNOTATE_TEMPLATES);
+  }
+
 
   public static function versionHasCapability(
     $mercurial_version,
@@ -70,6 +99,10 @@ final class PhutilMercurialBinaryAnalyzer
         return version_compare($mercurial_version, '3.2', '>=');
       case self::CAPABILITY_INJECTION:
         return version_compare($mercurial_version, '3.2.4', '<');
+      case self::CAPABILITY_TEMPLATE_PNODE:
+        return version_compare($mercurial_version, '4.9', '>=');
+      case self::CAPABILTIY_ANNOTATE_TEMPLATES:
+        return version_compare($mercurial_version, '4.6', '>=');
       default:
         throw new Exception(
           pht(