feat: Data and client framework

customcmd/parser/context.py

@@ -0,0 +1,48 @@
+from typing import TYPE_CHECKING, Any
+
+
+if TYPE_CHECKING:
+    from .terms import ExecutorTerm
+
+
+class ExecContext:
+    """
+    Base context class that carries the instantiation state.
+
+    This is passed to all CommandTerms upon execution.
+    """
+
+    def __init__(self, *, alias: str, args: list[str], content: str, initial_globals: dict[str, Any] = {}, **kwargs):
+        self.alias = alias
+        self.args = args
+        self.content = content
+
+        # Stack of scopes
+        # Initialising globals this way to avoid modifying default arg
+        globals = {} | initial_globals
+        self.scopes: list[dict[str, Any]] = [globals]
+
+        # Stack of terms that are *currently* executing with this context.
+        self.termstack: list['ExecutorTerm'] = []
+
+    def enter_scope(self, *args, **kwargs):
+        new_scope = dict(*args, **kwargs)
+        self.scopes.append(new_scope)
+
+    def leave_scope(self):
+        if len(self.scopes) > 1:
+            self.scopes.pop()
+        else:
+            raise ValueError("Cannot leave global scope")
+
+    @property
+    def scope(self):
+        # TODO: Move this to a more efficient ExecScope mapping type at some point
+        fullscope = {}
+        for scope in self.scopes:
+            fullscope |= scope
+        return fullscope
+
+    @property
+    def this_scope(self):
+        return self.scopes[-1]