Update sandbox to use virtual directories

2 files changed, 17 insertions, 4 deletions

diff --git a/src/buildstream/sandbox/sandbox.py b/src/buildstream/sandbox/sandbox.py
index 4cab7d6b8..3229b2dc6 100644
--- a/src/buildstream/sandbox/sandbox.py
+++ b/src/buildstream/sandbox/sandbox.py
@@ -548,13 +548,17 @@ class Sandbox():
     #     Returns:
     #         (bool): Whether a command exists inside the sandbox.
     def _has_command(self, command, env=None):
+        vroot = self.get_virtual_directory()
+        command_as_parts = command.lstrip(os.sep).split(os.sep)
         if os.path.isabs(command):
-            return os.path.lexists(os.path.join(
-                self._root, command.lstrip(os.sep)))
+            return vroot._exists(*command_as_parts, follow_symlinks=True)
+
+        if len(command_as_parts) > 1:
+            return False
 
         for path in env.get('PATH').split(':'):
-            if os.path.lexists(os.path.join(
-                    self._root, path.lstrip(os.sep), command)):
+            path_as_parts = path.lstrip(os.sep).split(os.sep)
+            if vroot._exists(*path_as_parts, command, follow_symlinks=True):
                 return True
 
         return False
diff --git a/src/buildstream/storage/_filebaseddirectory.py b/src/buildstream/storage/_filebaseddirectory.py
index a083f6507..07c23c192 100644
--- a/src/buildstream/storage/_filebaseddirectory.py
+++ b/src/buildstream/storage/_filebaseddirectory.py
@@ -285,3 +285,12 @@ class FileBasedDirectory(Directory):
                     assert entry.type == _FileType.SYMLINK
                     os.symlink(entry.target, dest_path)
                 result.files_written.append(relative_pathname)
+
+    def _exists(self, *path, follow_symlinks=False):
+        """This is very simple but mirrors the cas based storage were it is less trivial"""
+        if follow_symlinks:
+            # The lexists is not ideal as it cant spot broken symlinks but this is a long
+            # standing bug in buildstream as exists follow absolute syslinks to real root
+            # and incorrectly thinks they are broken the new casbaseddirectory dose not have this bug.
+            return os.path.lexists(os.path.join(self.external_directory, *path))
+        raise ImplError("_exists can only follow symlinks in filebaseddirectory")