Junk table dispatch for execute

projects/vfs/src/python/vfs/impl.py

@@ -16,21 +16,15 @@ class Vfs(object):
     def __init__(self, log=None):
         self._log = log or []
 
-    def execute(self, /, callback=None):
+    def _execute_exec(self, e):
-        for e in self._log:
-            _log.debug(e)
-            if callback:
-                callback(e)
-
-            if e[0] == "exec":
         _, dir, cmd = e
         run(cmd, cwd=str(dir))
 
-            elif e[0] == "link":
+    def _execute_link(self, e):
         _, src, dest = e
         if dest.is_file() or dest.is_symlink():
             if dest.is_symlink() and dest.readlink() == src:
-                        continue
+                return
             else:
                 _log.warn(f"Replacing {dest}")
                 dest.unlink()
@@ -41,27 +35,24 @@ class Vfs(object):
         assert not dest.exists(), f"{dest} should not exist"
         dest.symlink_to(src)
 
-            elif e[0] == "copy":
+    def _execute_chmod(self, e):
-                raise NotImplementedError()
-
-            elif e[0] == "chmod":
         _, dest, mode = e
         dest.chmod(mode)
 
-            elif e[0] == "mkdir":
+    def _execute_mkdir(self, e):
         _, dest = e
         if dest.is_dir():
-                    continue
+            return
         elif dest.exists() or dest.is_symlink():
             dest.unlink()
 
         dest.mkdir(exist_ok=True)
 
-            elif e[0] == "unlink":
+    def _execute_unlink(self, e):
         _, dest = e
         # Note that a path which is a dangling symlink will NOT exist but WILL be a symlink
         if not dest.exists() and not dest.is_symlink():
-                    continue
+            return
         # Files and dirs just unlink
         if dest.is_symlink() or dest.is_file():
             dest.unlink()
@@ -72,8 +63,28 @@ class Vfs(object):
         else:
             raise Exception(f"Couldn't unlink {dest}")
 
-    def _append(self, msg):
+    def _execute_unimplemented(self, e):
-        self._log.append(msg)
+        raise NotImplementedError()
+
+    def _entry_to_command(self, e):
+        return e
+
+    def execute(self, /, callback=None):
+        for e in self._log:
+            cmd = self._entry_to_command(e)
+            _log.debug(f"Executing %r as %r", e, cmd)
+
+            if callback:
+                callback(cmd)
+
+            # Using self as a dispatch table lol
+            getattr(self, f"_execute_{cmd[0]}", self._execute_unimplemented)(cmd)
+
+    def _command_to_entry(self, cmd):
+        return cmd
+
+    def _append(self, cmd):
+        self._log.append(self._command_to_entry(cmd))
 
     def link(self, src, dest):
         self._append(("link", src, dest))