Source code for robot.libraries.String

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import re
from fnmatch import fnmatchcase
from random import randint
from string import ascii_lowercase, ascii_uppercase, digits

from robot.api import logger
from robot.utils import (is_bytes, is_string, is_truthy, is_unicode, lower,
                         unic, PY3)
from robot.version import get_version


[docs]class String(object): """A test library for string manipulation and verification. ``String`` is Robot Framework's standard library for manipulating strings (e.g. `Replace String Using Regexp`, `Split To Lines`) and verifying their contents (e.g. `Should Be String`). Following keywords from ``BuiltIn`` library can also be used with strings: - `Catenate` - `Get Length` - `Length Should Be` - `Should (Not) Be Empty` - `Should (Not) Be Equal (As Strings/Integers/Numbers)` - `Should (Not) Match (Regexp)` - `Should (Not) Contain` - `Should (Not) Start With` - `Should (Not) End With` - `Convert To String` - `Convert To Bytes` """ ROBOT_LIBRARY_SCOPE = 'GLOBAL' ROBOT_LIBRARY_VERSION = get_version()
[docs] def convert_to_lowercase(self, string): """Converts string to lowercase. Examples: | ${str1} = | Convert To Lowercase | ABC | | ${str2} = | Convert To Lowercase | 1A2c3D | | Should Be Equal | ${str1} | abc | | Should Be Equal | ${str2} | 1a2c3d | New in Robot Framework 2.8.6. """ # Custom `lower` needed due to IronPython bug. See its code and # comments for more details. return lower(string)
[docs] def convert_to_uppercase(self, string): """Converts string to uppercase. Examples: | ${str1} = | Convert To Uppercase | abc | | ${str2} = | Convert To Uppercase | 1a2C3d | | Should Be Equal | ${str1} | ABC | | Should Be Equal | ${str2} | 1A2C3D | New in Robot Framework 2.8.6. """ return string.upper()
[docs] def encode_string_to_bytes(self, string, encoding, errors='strict'): """Encodes the given Unicode ``string`` to bytes using the given ``encoding``. ``errors`` argument controls what to do if encoding some characters fails. All values accepted by ``encode`` method in Python are valid, but in practice the following values are most useful: - ``strict``: fail if characters cannot be encoded (default) - ``ignore``: ignore characters that cannot be encoded - ``replace``: replace characters that cannot be encoded with a replacement character Examples: | ${bytes} = | Encode String To Bytes | ${string} | UTF-8 | | ${bytes} = | Encode String To Bytes | ${string} | ASCII | errors=ignore | Use `Convert To Bytes` in ``BuiltIn`` if you want to create bytes based on character or integer sequences. Use `Decode Bytes To String` if you need to convert byte strings to Unicode strings and `Convert To String` in ``BuiltIn`` if you need to convert arbitrary objects to Unicode. New in Robot Framework 2.7.7. """ return bytes(string.encode(encoding, errors))
[docs] def decode_bytes_to_string(self, bytes, encoding, errors='strict'): """Decodes the given ``bytes`` to a Unicode string using the given ``encoding``. ``errors`` argument controls what to do if decoding some bytes fails. All values accepted by ``decode`` method in Python are valid, but in practice the following values are most useful: - ``strict``: fail if characters cannot be decoded (default) - ``ignore``: ignore characters that cannot be decoded - ``replace``: replace characters that cannot be decoded with a replacement character Examples: | ${string} = | Decode Bytes To String | ${bytes} | UTF-8 | | ${string} = | Decode Bytes To String | ${bytes} | ASCII | errors=ignore | Use `Encode String To Bytes` if you need to convert Unicode strings to byte strings, and `Convert To String` in ``BuiltIn`` if you need to convert arbitrary objects to Unicode strings. New in Robot Framework 2.7.7. """ if PY3 and is_unicode(bytes): raise TypeError('Can not decode strings on Python 3.') return bytes.decode(encoding, errors)
[docs] def get_line_count(self, string): """Returns and logs the number of lines in the given string.""" count = len(string.splitlines()) logger.info('%d lines' % count) return count
[docs] def split_to_lines(self, string, start=0, end=None): """Splits the given string to lines. It is possible to get only a selection of lines from ``start`` to ``end`` so that ``start`` index is inclusive and ``end`` is exclusive. Line numbering starts from 0, and it is possible to use negative indices to refer to lines from the end. Lines are returned without the newlines. The number of returned lines is automatically logged. Examples: | @{lines} = | Split To Lines | ${manylines} | | | | @{ignore first} = | Split To Lines | ${manylines} | 1 | | | @{ignore last} = | Split To Lines | ${manylines} | | -1 | | @{5th to 10th} = | Split To Lines | ${manylines} | 4 | 10 | | @{first two} = | Split To Lines | ${manylines} | | 1 | | @{last two} = | Split To Lines | ${manylines} | -2 | | Use `Get Line` if you only need to get a single line. """ start = self._convert_to_index(start, 'start') end = self._convert_to_index(end, 'end') lines = string.splitlines()[start:end] logger.info('%d lines returned' % len(lines)) return lines
[docs] def get_line(self, string, line_number): """Returns the specified line from the given ``string``. Line numbering starts from 0 and it is possible to use negative indices to refer to lines from the end. The line is returned without the newline character. Examples: | ${first} = | Get Line | ${string} | 0 | | ${2nd last} = | Get Line | ${string} | -2 | Use `Split To Lines` if all lines are needed. """ line_number = self._convert_to_integer(line_number, 'line_number') return string.splitlines()[line_number]
[docs] def get_lines_containing_string(self, string, pattern, case_insensitive=False): """Returns lines of the given ``string`` that contain the ``pattern``. The ``pattern`` is always considered to be a normal string, not a glob or regexp pattern. A line matches if the ``pattern`` is found anywhere on it. The match is case-sensitive by default, but giving ``case_insensitive`` a true value makes it case-insensitive. The value is considered true if it is a non-empty string that is not equal to ``false`` or ``no``. If the value is not a string, its truth value is got directly in Python. Lines are returned as one string catenated back together with newlines. Possible trailing newline is never returned. The number of matching lines is automatically logged. Examples: | ${lines} = | Get Lines Containing String | ${result} | An example | | ${ret} = | Get Lines Containing String | ${ret} | FAIL | case-insensitive | See `Get Lines Matching Pattern` and `Get Lines Matching Regexp` if you need more complex pattern matching. """ if is_truthy(case_insensitive): pattern = pattern.lower() contains = lambda line: pattern in line.lower() else: contains = lambda line: pattern in line return self._get_matching_lines(string, contains)
[docs] def get_lines_matching_pattern(self, string, pattern, case_insensitive=False): """Returns lines of the given ``string`` that match the ``pattern``. The ``pattern`` is a _glob pattern_ where: | ``*`` | matches everything | | ``?`` | matches any single character | | ``[chars]`` | matches any character inside square brackets (e.g. ``[abc]`` matches either ``a``, ``b`` or ``c``) | | ``[!chars]`` | matches any character not inside square brackets | A line matches only if it matches the ``pattern`` fully. The match is case-sensitive by default, but giving ``case_insensitive`` a true value makes it case-insensitive. The value is considered true if it is a non-empty string that is not equal to ``false`` or ``no``. If the value is not a string, its truth value is got directly in Python. Lines are returned as one string catenated back together with newlines. Possible trailing newline is never returned. The number of matching lines is automatically logged. Examples: | ${lines} = | Get Lines Matching Pattern | ${result} | Wild???? example | | ${ret} = | Get Lines Matching Pattern | ${ret} | FAIL: * | case_insensitive=true | See `Get Lines Matching Regexp` if you need more complex patterns and `Get Lines Containing String` if searching literal strings is enough. """ if is_truthy(case_insensitive): pattern = pattern.lower() matches = lambda line: fnmatchcase(line.lower(), pattern) else: matches = lambda line: fnmatchcase(line, pattern) return self._get_matching_lines(string, matches)
[docs] def get_lines_matching_regexp(self, string, pattern, partial_match=False): """Returns lines of the given ``string`` that match the regexp ``pattern``. See `BuiltIn.Should Match Regexp` for more information about Python regular expression syntax in general and how to use it in Robot Framework test data in particular. By default lines match only if they match the pattern fully, but partial matching can be enabled by giving the ``partial_match`` argument a true value. The value is considered true if it is a non-empty string that is not equal to ``false`` or ``no``. If the value is not a string, its truth value is got directly in Python. If the pattern is empty, it matches only empty lines by default. When partial matching is enabled, empty pattern matches all lines. Notice that to make the match case-insensitive, you need to prefix the pattern with case-insensitive flag ``(?i)``. Lines are returned as one string concatenated back together with newlines. Possible trailing newline is never returned. The number of matching lines is automatically logged. Examples: | ${lines} = | Get Lines Matching Regexp | ${result} | Reg\\\\w{3} example | | ${lines} = | Get Lines Matching Regexp | ${result} | Reg\\\\w{3} example | partial_match=true | | ${ret} = | Get Lines Matching Regexp | ${ret} | (?i)FAIL: .* | See `Get Lines Matching Pattern` and `Get Lines Containing String` if you do not need full regular expression powers (and complexity). ``partial_match`` argument is new in Robot Framework 2.9. In earlier versions exact match was always required. """ if not is_truthy(partial_match): pattern = '^%s$' % pattern return self._get_matching_lines(string, re.compile(pattern).search)
def _get_matching_lines(self, string, matches): lines = string.splitlines() matching = [line for line in lines if matches(line)] logger.info('%d out of %d lines matched' % (len(matching), len(lines))) return '\n'.join(matching)
[docs] def get_regexp_matches(self, string, pattern, *groups): """Returns a list of all non-overlapping matches in the given string. ``string`` is the string to find matches from and ``pattern`` is the regular expression. See `BuiltIn.Should Match Regexp` for more information about Python regular expression syntax in general and how to use it in Robot Framework test data in particular. If no groups are used, the returned list contains full matches. If one group is used, the list contains only contents of that group. If multiple groups are used, the list contains tuples that contain individual group contents. All groups can be given as indexes (starting from 1) and named groups also as names. Examples: | ${no match} = | Get Regexp Matches | the string | xxx | | ${matches} = | Get Regexp Matches | the string | t.. | | ${one group} = | Get Regexp Matches | the string | t(..) | 1 | | ${named group} = | Get Regexp Matches | the string | t(?P<name>..) | name | | ${two groups} = | Get Regexp Matches | the string | t(.)(.) | 1 | 2 | => | ${no match} = [] | ${matches} = ['the', 'tri'] | ${one group} = ['he', 'ri'] | ${named group} = ['he', 'ri'] | ${two groups} = [('h', 'e'), ('r', 'i')] New in Robot Framework 2.9. """ regexp = re.compile(pattern) groups = [self._parse_group(g) for g in groups] return [m.group(*groups) for m in regexp.finditer(string)]
def _parse_group(self, group): try: return int(group) except ValueError: return group
[docs] def replace_string(self, string, search_for, replace_with, count=-1): """Replaces ``search_for`` in the given ``string`` with ``replace_with``. ``search_for`` is used as a literal string. See `Replace String Using Regexp` if more powerful pattern matching is needed. If you need to just remove a string see `Remove String`. If the optional argument ``count`` is given, only that many occurrences from left are replaced. Negative ``count`` means that all occurrences are replaced (default behaviour) and zero means that nothing is done. A modified version of the string is returned and the original string is not altered. Examples: | ${str} = | Replace String | Hello, world! | world | tellus | | Should Be Equal | ${str} | Hello, tellus! | | | | ${str} = | Replace String | Hello, world! | l | ${EMPTY} | count=1 | | Should Be Equal | ${str} | Helo, world! | | | """ count = self._convert_to_integer(count, 'count') return string.replace(search_for, replace_with, count)
[docs] def replace_string_using_regexp(self, string, pattern, replace_with, count=-1): """Replaces ``pattern`` in the given ``string`` with ``replace_with``. This keyword is otherwise identical to `Replace String`, but the ``pattern`` to search for is considered to be a regular expression. See `BuiltIn.Should Match Regexp` for more information about Python regular expression syntax in general and how to use it in Robot Framework test data in particular. If you need to just remove a string see `Remove String Using Regexp`. Examples: | ${str} = | Replace String Using Regexp | ${str} | 20\\\\d\\\\d-\\\\d\\\\d-\\\\d\\\\d | <DATE> | | ${str} = | Replace String Using Regexp | ${str} | (Hello|Hi) | ${EMPTY} | count=1 | """ count = self._convert_to_integer(count, 'count') # re.sub handles 0 and negative counts differently than string.replace if count == 0: return string return re.sub(pattern, replace_with, string, max(count, 0))
[docs] def remove_string(self, string, *removables): """Removes all ``removables`` from the given ``string``. ``removables`` are used as literal strings. Each removable will be matched to a temporary string from which preceding removables have been already removed. See second example below. Use `Remove String Using Regexp` if more powerful pattern matching is needed. If only a certain number of matches should be removed, `Replace String` or `Replace String Using Regexp` can be used. A modified version of the string is returned and the original string is not altered. Examples: | ${str} = | Remove String | Robot Framework | work | | Should Be Equal | ${str} | Robot Frame | | ${str} = | Remove String | Robot Framework | o | bt | | Should Be Equal | ${str} | R Framewrk | New in Robot Framework 2.8.2. """ for removable in removables: string = self.replace_string(string, removable, '') return string
[docs] def remove_string_using_regexp(self, string, *patterns): """Removes ``patterns`` from the given ``string``. This keyword is otherwise identical to `Remove String`, but the ``patterns`` to search for are considered to be a regular expression. See `Replace String Using Regexp` for more information about the regular expression syntax. That keyword can also be used if there is a need to remove only a certain number of occurrences. New in Robot Framework 2.8.2. """ for pattern in patterns: string = self.replace_string_using_regexp(string, pattern, '') return string
[docs] def split_string(self, string, separator=None, max_split=-1): """Splits the ``string`` using ``separator`` as a delimiter string. If a ``separator`` is not given, any whitespace string is a separator. In that case also possible consecutive whitespace as well as leading and trailing whitespace is ignored. Split words are returned as a list. If the optional ``max_split`` is given, at most ``max_split`` splits are done, and the returned list will have maximum ``max_split + 1`` elements. Examples: | @{words} = | Split String | ${string} | | @{words} = | Split String | ${string} | ,${SPACE} | | ${pre} | ${post} = | Split String | ${string} | :: | 1 | See `Split String From Right` if you want to start splitting from right, and `Fetch From Left` and `Fetch From Right` if you only want to get first/last part of the string. """ if separator == '': separator = None max_split = self._convert_to_integer(max_split, 'max_split') return string.split(separator, max_split)
[docs] def split_string_from_right(self, string, separator=None, max_split=-1): """Splits the ``string`` using ``separator`` starting from right. Same as `Split String`, but splitting is started from right. This has an effect only when ``max_split`` is given. Examples: | ${first} | ${rest} = | Split String | ${string} | - | 1 | | ${rest} | ${last} = | Split String From Right | ${string} | - | 1 | """ if separator == '': separator = None max_split = self._convert_to_integer(max_split, 'max_split') return string.rsplit(separator, max_split)
[docs] def split_string_to_characters(self, string): """Splits the given ``string`` to characters. Example: | @{characters} = | Split String To Characters | ${string} | New in Robot Framework 2.7. """ return list(string)
[docs] def fetch_from_left(self, string, marker): """Returns contents of the ``string`` before the first occurrence of ``marker``. If the ``marker`` is not found, whole string is returned. See also `Fetch From Right`, `Split String` and `Split String From Right`. """ return string.split(marker)[0]
[docs] def fetch_from_right(self, string, marker): """Returns contents of the ``string`` after the last occurrence of ``marker``. If the ``marker`` is not found, whole string is returned. See also `Fetch From Left`, `Split String` and `Split String From Right`. """ return string.split(marker)[-1]
[docs] def generate_random_string(self, length=8, chars='[LETTERS][NUMBERS]'): """Generates a string with a desired ``length`` from the given ``chars``. The population sequence ``chars`` contains the characters to use when generating the random string. It can contain any characters, and it is possible to use special markers explained in the table below: | = Marker = | = Explanation = | | ``[LOWER]`` | Lowercase ASCII characters from ``a`` to ``z``. | | ``[UPPER]`` | Uppercase ASCII characters from ``A`` to ``Z``. | | ``[LETTERS]`` | Lowercase and uppercase ASCII characters. | | ``[NUMBERS]`` | Numbers from 0 to 9. | Examples: | ${ret} = | Generate Random String | | ${low} = | Generate Random String | 12 | [LOWER] | | ${bin} = | Generate Random String | 8 | 01 | | ${hex} = | Generate Random String | 4 | [NUMBERS]abcdef | """ if length == '': length = 8 length = self._convert_to_integer(length, 'length') for name, value in [('[LOWER]', ascii_lowercase), ('[UPPER]', ascii_uppercase), ('[LETTERS]', ascii_lowercase + ascii_uppercase), ('[NUMBERS]', digits)]: chars = chars.replace(name, value) maxi = len(chars) - 1 return ''.join(chars[randint(0, maxi)] for _ in range(length))
[docs] def get_substring(self, string, start, end=None): """Returns a substring from ``start`` index to ``end`` index. The ``start`` index is inclusive and ``end`` is exclusive. Indexing starts from 0, and it is possible to use negative indices to refer to characters from the end. Examples: | ${ignore first} = | Get Substring | ${string} | 1 | | | ${ignore last} = | Get Substring | ${string} | | -1 | | ${5th to 10th} = | Get Substring | ${string} | 4 | 10 | | ${first two} = | Get Substring | ${string} | | 1 | | ${last two} = | Get Substring | ${string} | -2 | | """ start = self._convert_to_index(start, 'start') end = self._convert_to_index(end, 'end') return string[start:end]
[docs] def strip_string(self, string, mode='both', characters=None): """Remove leading and/or trailing whitespaces from the given string. ``mode`` is either ``left`` to remove leading characters, ``right`` to remove trailing characters, ``both`` (default) to remove the characters from both sides of the string or ``none`` to return the unmodified string. If the optional ``characters`` is given, it must be a string and the characters in the string will be stripped in the string. Please note, that this is not a substring to be removed but a list of characters, see the example below. Examples: | ${stripped}= | Strip String | ${SPACE}Hello${SPACE} | | | Should Be Equal | ${stripped} | Hello | | | ${stripped}= | Strip String | ${SPACE}Hello${SPACE} | mode=left | | Should Be Equal | ${stripped} | Hello${SPACE} | | | ${stripped}= | Strip String | aabaHelloeee | characters=abe | | Should Be Equal | ${stripped} | Hello | | New in Robot Framework 3.0. """ try: method = {'BOTH': string.strip, 'LEFT': string.lstrip, 'RIGHT': string.rstrip, 'NONE': lambda characters: string}[mode.upper()] except KeyError: raise ValueError("Invalid mode '%s'." % mode) return method(characters)
[docs] def should_be_string(self, item, msg=None): """Fails if the given ``item`` is not a string. This keyword passes regardless is the ``item`` is a Unicode string or a byte string. Use `Should Be Unicode String` or `Should Be Byte String` if you want to restrict the string type. The default error message can be overridden with the optional ``msg`` argument. """ if not is_string(item): self._fail(msg, "'%s' is not a string.", item)
[docs] def should_not_be_string(self, item, msg=None): """Fails if the given ``item`` is a string. The default error message can be overridden with the optional ``msg`` argument. """ if is_string(item): self._fail(msg, "'%s' is a string.", item)
[docs] def should_be_unicode_string(self, item, msg=None): """Fails if the given ``item`` is not a Unicode string. Use `Should Be Byte String` if you want to verify the ``item`` is a byte string, or `Should Be String` if both Unicode and byte strings are fine. The default error message can be overridden with the optional ``msg`` argument. New in Robot Framework 2.7.7. """ if not is_unicode(item): self._fail(msg, "'%s' is not a Unicode string.", item)
[docs] def should_be_byte_string(self, item, msg=None): """Fails if the given ``item`` is not a byte string. Use `Should Be Unicode String` if you want to verify the ``item`` is a Unicode string, or `Should Be String` if both Unicode and byte strings are fine. The default error message can be overridden with the optional ``msg`` argument. New in Robot Framework 2.7.7. """ if not is_bytes(item): self._fail(msg, "'%s' is not a byte string.", item)
[docs] def should_be_lowercase(self, string, msg=None): """Fails if the given ``string`` is not in lowercase. For example, ``'string'`` and ``'with specials!'`` would pass, and ``'String'``, ``''`` and ``' '`` would fail. The default error message can be overridden with the optional ``msg`` argument. See also `Should Be Uppercase` and `Should Be Titlecase`. """ if not string.islower(): self._fail(msg, "'%s' is not lowercase.", string)
[docs] def should_be_uppercase(self, string, msg=None): """Fails if the given ``string`` is not in uppercase. For example, ``'STRING'`` and ``'WITH SPECIALS!'`` would pass, and ``'String'``, ``''`` and ``' '`` would fail. The default error message can be overridden with the optional ``msg`` argument. See also `Should Be Titlecase` and `Should Be Lowercase`. """ if not string.isupper(): self._fail(msg, "'%s' is not uppercase.", string)
[docs] def should_be_titlecase(self, string, msg=None): """Fails if given ``string`` is not title. ``string`` is a titlecased string if there is at least one character in it, uppercase characters only follow uncased characters and lowercase characters only cased ones. For example, ``'This Is Title'`` would pass, and ``'Word In UPPER'``, ``'Word In lower'``, ``''`` and ``' '`` would fail. The default error message can be overridden with the optional ``msg`` argument. See also `Should Be Uppercase` and `Should Be Lowercase`. """ if not string.istitle(): self._fail(msg, "'%s' is not titlecase.", string)
def _convert_to_index(self, value, name): if value == '': return 0 if value is None: return None return self._convert_to_integer(value, name) def _convert_to_integer(self, value, name): try: return int(value) except ValueError: raise ValueError("Cannot convert '%s' argument '%s' to an integer." % (name, value)) def _fail(self, message, default_template, *items): if not message: message = default_template % tuple(unic(item) for item in items) raise AssertionError(message)