1 files changed, 114 insertions, 0 deletions
diff --git a/Lib/_pyrepl/input.py b/Lib/_pyrepl/input.py
new file mode 100644
index 00000000000..300e16d1d25
--- /dev/null
+++ b/Lib/_pyrepl/input.py
@@ -0,0 +1,114 @@
+#   Copyright 2000-2004 Michael Hudson-Doyle <micahel@gmail.com>
+#
+#                        All Rights Reserved
+#
+#
+# Permission to use, copy, modify, and distribute this software and
+# its documentation for any purpose is hereby granted without fee,
+# provided that the above copyright notice appear in all copies and
+# that both that copyright notice and this permission notice appear in
+# supporting documentation.
+#
+# THE AUTHOR MICHAEL HUDSON DISCLAIMS ALL WARRANTIES WITH REGARD TO
+# THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+# AND FITNESS, IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL,
+# INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER
+# RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF
+# CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+# CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+
+# (naming modules after builtin functions is not such a hot idea...)
+
+# an KeyTrans instance translates Event objects into Command objects
+
+# hmm, at what level do we want [C-i] and [tab] to be equivalent?
+# [meta-a] and [esc a]?  obviously, these are going to be equivalent
+# for the UnixConsole, but should they be for PygameConsole?
+
+# it would in any situation seem to be a bad idea to bind, say, [tab]
+# and [C-i] to *different* things... but should binding one bind the
+# other?
+
+# executive, temporary decision: [tab] and [C-i] are distinct, but
+# [meta-key] is identified with [esc key].  We demand that any console
+# class does quite a lot towards emulating a unix terminal.
+
+from __future__ import annotations
+
+from abc import ABC, abstractmethod
+import unicodedata
+from collections import deque
+
+
+# types
+if False:
+    from .types import EventTuple
+
+
+class InputTranslator(ABC):
+    @abstractmethod
+    def push(self, evt: EventTuple) -> None:
+        pass
+
+    @abstractmethod
+    def get(self) -> EventTuple | None:
+        return None
+
+    @abstractmethod
+    def empty(self) -> bool:
+        return True
+
+
+class KeymapTranslator(InputTranslator):
+    def __init__(self, keymap, verbose=0, invalid_cls=None, character_cls=None):
+        self.verbose = verbose
+        from .keymap import compile_keymap, parse_keys
+
+        self.keymap = keymap
+        self.invalid_cls = invalid_cls
+        self.character_cls = character_cls
+        d = {}
+        for keyspec, command in keymap:
+            keyseq = tuple(parse_keys(keyspec))
+            d[keyseq] = command
+        if self.verbose:
+            print(d)
+        self.k = self.ck = compile_keymap(d, ())
+        self.results = deque()
+        self.stack = []
+
+    def push(self, evt):
+        if self.verbose:
+            print("pushed", evt.data, end="")
+        key = evt.data
+        d = self.k.get(key)
+        if isinstance(d, dict):
+            if self.verbose:
+                print("transition")
+            self.stack.append(key)
+            self.k = d
+        else:
+            if d is None:
+                if self.verbose:
+                    print("invalid")
+                if self.stack or len(key) > 1 or unicodedata.category(key) == "C":
+                    self.results.append((self.invalid_cls, self.stack + [key]))
+                else:
+                    # small optimization:
+                    self.k[key] = self.character_cls
+                    self.results.append((self.character_cls, [key]))
+            else:
+                if self.verbose:
+                    print("matched", d)
+                self.results.append((d, self.stack + [key]))
+            self.stack = []
+            self.k = self.ck
+
+    def get(self):
+        if self.results:
+            return self.results.popleft()
+        else:
+            return None
+
+    def empty(self):
+        return not self.results