1 files changed, 154 insertions, 0 deletions
diff --git a/third_party/python/pip/pip/_vendor/rich/cells.py b/third_party/python/pip/pip/_vendor/rich/cells.py
new file mode 100644
index 0000000000..139b949f7f
--- /dev/null
+++ b/third_party/python/pip/pip/_vendor/rich/cells.py
@@ -0,0 +1,154 @@
+import re
+from functools import lru_cache
+from typing import Callable, List
+
+from ._cell_widths import CELL_WIDTHS
+
+# Regex to match sequence of the most common character ranges
+_is_single_cell_widths = re.compile("^[\u0020-\u006f\u00a0\u02ff\u0370-\u0482]*$").match
+
+
+@lru_cache(4096)
+def cached_cell_len(text: str) -> int:
+    """Get the number of cells required to display text.
+
+    This method always caches, which may use up a lot of memory. It is recommended to use
+    `cell_len` over this method.
+
+    Args:
+        text (str): Text to display.
+
+    Returns:
+        int: Get the number of cells required to display text.
+    """
+    _get_size = get_character_cell_size
+    total_size = sum(_get_size(character) for character in text)
+    return total_size
+
+
+def cell_len(text: str, _cell_len: Callable[[str], int] = cached_cell_len) -> int:
+    """Get the number of cells required to display text.
+
+    Args:
+        text (str): Text to display.
+
+    Returns:
+        int: Get the number of cells required to display text.
+    """
+    if len(text) < 512:
+        return _cell_len(text)
+    _get_size = get_character_cell_size
+    total_size = sum(_get_size(character) for character in text)
+    return total_size
+
+
+@lru_cache(maxsize=4096)
+def get_character_cell_size(character: str) -> int:
+    """Get the cell size of a character.
+
+    Args:
+        character (str): A single character.
+
+    Returns:
+        int: Number of cells (0, 1 or 2) occupied by that character.
+    """
+    return _get_codepoint_cell_size(ord(character))
+
+
+@lru_cache(maxsize=4096)
+def _get_codepoint_cell_size(codepoint: int) -> int:
+    """Get the cell size of a character.
+
+    Args:
+        character (str): A single character.
+
+    Returns:
+        int: Number of cells (0, 1 or 2) occupied by that character.
+    """
+
+    _table = CELL_WIDTHS
+    lower_bound = 0
+    upper_bound = len(_table) - 1
+    index = (lower_bound + upper_bound) // 2
+    while True:
+        start, end, width = _table[index]
+        if codepoint < start:
+            upper_bound = index - 1
+        elif codepoint > end:
+            lower_bound = index + 1
+        else:
+            return 0 if width == -1 else width
+        if upper_bound < lower_bound:
+            break
+        index = (lower_bound + upper_bound) // 2
+    return 1
+
+
+def set_cell_size(text: str, total: int) -> str:
+    """Set the length of a string to fit within given number of cells."""
+
+    if _is_single_cell_widths(text):
+        size = len(text)
+        if size < total:
+            return text + " " * (total - size)
+        return text[:total]
+
+    if total <= 0:
+        return ""
+    cell_size = cell_len(text)
+    if cell_size == total:
+        return text
+    if cell_size < total:
+        return text + " " * (total - cell_size)
+
+    start = 0
+    end = len(text)
+
+    # Binary search until we find the right size
+    while True:
+        pos = (start + end) // 2
+        before = text[: pos + 1]
+        before_len = cell_len(before)
+        if before_len == total + 1 and cell_len(before[-1]) == 2:
+            return before[:-1] + " "
+        if before_len == total:
+            return before
+        if before_len > total:
+            end = pos
+        else:
+            start = pos
+
+
+# TODO: This is inefficient
+# TODO: This might not work with CWJ type characters
+def chop_cells(text: str, max_size: int, position: int = 0) -> List[str]:
+    """Break text in to equal (cell) length strings, returning the characters in reverse
+    order"""
+    _get_character_cell_size = get_character_cell_size
+    characters = [
+        (character, _get_character_cell_size(character)) for character in text
+    ]
+    total_size = position
+    lines: List[List[str]] = [[]]
+    append = lines[-1].append
+
+    for character, size in reversed(characters):
+        if total_size + size > max_size:
+            lines.append([character])
+            append = lines[-1].append
+            total_size = size
+        else:
+            total_size += size
+            append(character)
+
+    return ["".join(line) for line in lines]
+
+
+if __name__ == "__main__":  # pragma: no cover
+
+    print(get_character_cell_size("😽"))
+    for line in chop_cells("""这是对亚洲语言支持的测试。面对模棱两可的想法，拒绝猜测的诱惑。""", 8):
+        print(line)
+    for n in range(80, 1, -1):
+        print(set_cell_size("""这是对亚洲语言支持的测试。面对模棱两可的想法，拒绝猜测的诱惑。""", n) + "|")
+        print("x" * n)