# Copyright (c) Streamlit Inc. (2018-2022) Snowflake Inc. (2022-2024)
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
from __future__ import annotations
import re
import textwrap
from typing import TYPE_CHECKING, Any, Final, cast
from streamlit.errors import StreamlitAPIException
if TYPE_CHECKING:
from streamlit.type_util import SupportsStr
_ALPHANUMERIC_CHAR_REGEX: Final = re.compile(r"^[a-zA-Z0-9_&\-\. ]+$")
def decode_ascii(string: bytes) -> str:
"""Decodes a string as ascii."""
return string.decode("ascii")
def clean_text(text: SupportsStr) -> str:
"""Convert an object to text, dedent it, and strip whitespace."""
return textwrap.dedent(str(text)).strip()
def _contains_special_chars(text: str) -> bool:
"""Check if a string contains any special chars.
Special chars in that case are all chars that are not
alphanumeric, underscore, hyphen or whitespace.
"""
return re.match(_ALPHANUMERIC_CHAR_REGEX, text) is None if text else False
def is_emoji(text: str) -> bool:
"""Check if input string is a valid emoji."""
if not _contains_special_chars(text):
return False
from streamlit.emojis import ALL_EMOJIS
return text.replace("\U0000FE0F", "") in ALL_EMOJIS
def is_material_icon(maybe_icon: str) -> bool:
"""Check if input string is a valid Material icon."""
from streamlit.material_icon_names import ALL_MATERIAL_ICONS
return maybe_icon in ALL_MATERIAL_ICONS
def validate_icon_or_emoji(icon: str | None) -> str:
"""Validate an icon or emoji and return it in normalized format if valid."""
if icon is not None and icon.startswith(":material"):
return validate_material_icon(icon)
return validate_emoji(icon)
def validate_emoji(maybe_emoji: str | None) -> str:
if maybe_emoji is None:
return ""
elif is_emoji(maybe_emoji):
return maybe_emoji
else:
raise StreamlitAPIException(
f'The value "{maybe_emoji}" is not a valid emoji. Shortcodes are not allowed, please use a single character instead.'
)
def validate_material_icon(maybe_material_icon: str | None) -> str:
"""Validate a Material icon shortcode and return the icon in
normalized format if valid."""
supported_icon_packs = [
"material",
]
if maybe_material_icon is None:
return ""
icon_regex = r"^\s*:(.+)\/(.+):\s*$"
icon_match = re.match(icon_regex, maybe_material_icon)
if not icon_match:
raise StreamlitAPIException(
f'The value `"{maybe_material_icon}"` is not a valid Material icon. '
f"Please use a Material icon shortcode like **`:material/thumb_up:`**"
)
pack_name, icon_name = icon_match.groups()
if (
pack_name not in supported_icon_packs
or not icon_name
or not is_material_icon(icon_name)
):
raise StreamlitAPIException(
f'The value `"{maybe_material_icon}"` is not a valid Material icon.'
f" Please use a Material icon shortcode like **`:material/thumb_up:`**. "
)
return f":{pack_name}/{icon_name}:"
def extract_leading_emoji(text: str) -> tuple[str, str]:
"""Return a tuple containing the first emoji found in the given string and
the rest of the string (minus an optional separator between the two).
"""
if not _contains_special_chars(text):
# If the string only contains basic alphanumerical chars and/or
# underscores, hyphen & whitespaces, then it's guaranteed that there
# is no emoji in the string.
return "", text
from streamlit.emojis import EMOJI_EXTRACTION_REGEX
re_match = re.search(EMOJI_EXTRACTION_REGEX, text)
if re_match is None:
return "", text
# This cast to Any+type annotation weirdness is done because
# cast(re.Match[str], ...) explodes at runtime since Python interprets it
# as an attempt to index into re.Match instead of as a type annotation.
re_match: re.Match[str] = cast(Any, re_match)
return re_match.group(1), re_match.group(2)
def max_char_sequence(string: str, char: str) -> int:
"""Returns the count of the max sequence of a given char in a string."""
max_sequence = 0
current_sequence = 0
for c in string:
if c == char:
current_sequence += 1
max_sequence = max(max_sequence, current_sequence)
else:
current_sequence = 0
return max_sequence
TEXTCHARS: Final = bytearray(
{7, 8, 9, 10, 12, 13, 27} | set(range(0x20, 0x100)) - {0x7F}
)
def is_binary_string(inp: bytes) -> bool:
"""Guess if an input bytesarray can be encoded as a string."""
# From https://stackoverflow.com/a/7392391
return bool(inp.translate(None, TEXTCHARS))
def simplify_number(num: int) -> str:
"""Simplifies number into Human readable format, returns str"""
num_converted = float(f"{num:.2g}")
magnitude = 0
while abs(num_converted) >= 1000:
magnitude += 1
num_converted /= 1000.0
return "{}{}".format(
f"{num_converted:f}".rstrip("0").rstrip("."),
["", "k", "m", "b", "t"][magnitude],
)
_OBJ_MEM_ADDRESS: Final = re.compile(
r"^\<[a-zA-Z_]+[a-zA-Z0-9<>._ ]* at 0x[0-9a-f]+\>$"
)
def is_mem_address_str(string):
"""Returns True if the string looks like <foo blarg at 0x15ee6f9a0>."""
if _OBJ_MEM_ADDRESS.match(string):
return True
return False
_RE_CONTAINS_HTML: Final = re.compile(r"(?:</[^<]+>)|(?:<[^<]+/>)")
def probably_contains_html_tags(s: str) -> bool:
"""Returns True if the given string contains what seem to be HTML tags.
Note that false positives/negatives are possible, so this function should not be
used in contexts where complete correctness is required."""
return bool(_RE_CONTAINS_HTML.search(s))