User:松/Drafts/Extension:AbuseFilter/Rules format

    From TestWiki

    The rules are formatted much as conditionals in a C/Java/Perl-like language.

    Strings

    You can specify a literal by placing it in single or double quotes (for strings), or by typing it in as-is (for numbers, both floating-point and integer).

    You can get linebreaks with \n, tab characters with \t, and you can also escape the quote character with a backslash.

    Use the + (plus) symbol to concatenate two literal strings or the values of two vars with a string value.

    Examples
    " This is a string"
    ' This is also a string'
    ' This string shouldn\'t fail'
    " This string\nHas a linebreak"
    1234
    1.234
    -123
    

    User-defined variables

    You can define custom variables for ease of understanding with the assign symbol := in a line (closed by ;) within a condition.

    Such variables may use letters, underscores, and numbers (apart from the first character) and are case-insensitive.

    Example (from w:Special:AbuseFilter/79):

    (
    	line1:="(\{\{(r|R)eflist|\{\{(r|R)efs|<references\s?/>|</references\s?>)";
    	rcount(line1, removed_lines)
    ) > (
    	rcount(line1, added_lines)
    )
    

    Arrays

    AbuseFilter has support for non-associative arrays, which can be used like in the following examples.

    Template:Caution

    my_array := [ 5, 6, 7, 10];
    my_array[0] == 5
    length(my_array) == 4
    int( my_array ) === 4 //  Same as length
    float( my_array ) === 4.0 //  Counts the elements
    string(my_array) == "5\n6\n7\n10\n" // Note: the last linebreak could be removed in the future
    5 in my_array == true
    '5' in my_array == true
    '5\n6' in my_array == true // Note: this is due to how arrays are casted to string, i.e. by imploding them with linebreaks
    1 in my_array == true // Note: this happens because 'in' casts arguments to strings, so the 1 is caught in '10' and returns true.
    my_array[] := 57 //  This appends an element at the end of the array
    my_array === [ 5, 6, 7, 10, 57 ]
    my_array[2] := 42 //  And this is for changing an element in the array
    my_array === [ 5, 6, 42, 10, 57 ]
    

    Comments

    You can specify comments using the following syntax:

    /* This is a comment */
    

    Arithmetic

    You can use basic arithmetic symbols to do arithmetic on variables and literals with the following syntax:

    • - — Subtract the right-hand operand from the left-hand operand.
    • + — Add the right-hand operand to the left-hand operand.
    • * — Multiply the left-hand operand by the right-hand operand.
    • / — Divide the left-hand operand by the right-hand operand.
    • ** — Raise the left-hand operand to the exponential power specified by the right-hand operand.
    • % — Return the remainder given when the left-hand operand is divided by the right-hand operand.

    The type of the returned result is the same that would be returned by PHP, for which a lot of documentation may be found online.

    More exhaustive examples may be found in this AF parser test.

    Example Result
    1 + 1 2
    2 * 2 4
    1 / 2 0.5
    9 ** 2 81
    6 % 5 1

    Boolean operations

    You can match if and only if all of a number of conditions are true, one of a number of conditions are true, or one and only one of all conditions are true.

    • x | y — OR – returns true if one or more of the conditions is true.
    • x & y — AND – returns true if both of the conditions are true.
    • x ^ y — XOR – returns true if one, and only one of the two conditions is true.
    • !x — NOT – returns true if the condition is not true.

    Examples

    Code Result
    1 | 1 true
    1 | 0 true
    0 | 0 false
    1 & 1 true
    1 & 0 false
    0 & 0 false
    1 ^ 1 false
    1 ^ 0 true
    0 ^ 0 false
    !1 false
    !0 true

    Simple comparisons

    You can compare variables with other variables and literals with the following syntax:

    • <Template:Int> — Return true if the left-hand operand is less than/greater than the right-hand operand respectively. Watch out: operands are casted to strings and, like it happens in PHP, null < any number === true and null > any number === false.
    • <=Template:Int>= — Return true if the left-hand operand is less than or equal to/greater than or equal to the right-hand operand respectively.Watch out: operands are casted to strings and, like it happens in PHP, null <= any number === true and null >= any number === false.
    • == (or=), != — Return true if the left-hand operand is equal to/not equal to the right-hand operand respectively.
    • ===Template:Int!== — Return true if the left-hand operand is equal to/not equal to the right-hand operand AND the left-hand operand is the same/not the same data type to the right-hand operand respectively.
    Example Result
    1 == 2 false
    1 <= 2 true
    1 >= 2 false
    1 != 2 true
    1 < 2 true
    1 > 2 false
    2 = 2 true
    '' == false true
    '' === false false
    1 == true true
    1 === true false
    ['1','2','3'] == ['1','2','3'] true
    [1,2,3] === [1,2,3] true
    ['1','2','3'] == [1,2,3] true
    ['1','2','3'] === [1,2,3] false
    [1,1,''] == [true, true, false] true
    [] == false & [] == null true
    ['1'] == '1' false[1]

    Built-in variables 

    The abuse filter passes various variables by name into the parser.These variables can be accessed by typing their name in, in a place where a literal would work.You can view the variables associated with each request in the abuse log.

    Variables from AbuseFilter

    Variables always available

    Template:Caution

    Description Name Data type Notes
    Action action string One of the following:edit, move, createaccount, autocreateaccount, delete, upload[2], stashupload[3]
    Unix timestamp of change timestamp string int(timestamp) gives you a number with which you can calculate the date, time, day of week, etc.
    Template:Int wiki_name string For instance, this is "enwiki" on the English Wikipedia, and "itwikiquote" on the Italian Wikiquote.
    Template:Int wiki_language string For instance, this is "en" on the English Wikipedia, and "it" on the Italian Wikiquote. Multi-lingual wikis like Commons, Meta, and Wikidata will also report as "en".
    Template:Int user_editcount integer/null Null only for unregistered users.
    Template:Int user_name string  For "createaccount" and "autocreateaccount" actions, use accountname if you want the name of the account being created.:
    Template:Int user_emailconfirm string/null In the format: YYYYMMDDHHMMSS.Null if the email wasn't confirmed.
    Template:Int user_age integer In seconds.0 for unregistered users.
    Template:Int user_blocked boolean True for blocked registered users.Also true for edits from blocked IP addresses, even if the editor is a registered user who is not blocked.False otherwise.  This doesn't differentiate between partial and total blocks.:
    Template:Int user_groups array of strings see Special:ListGroupRights
    Template:Int user_rights array of strings see Special:ListGroupRights
    Template:Int article_articleid integer Template:Deprecated-inline Use page_id instead.
    Template:Ll (found in the page's HTML source - search for wgArticleId) page_id integer In theory this is 0 for new pages, but this is unreliable.If you need an exact result, use "page_age == 0" to identify new page creation. (note that it is slower, though.)
    Template:Int article_namespace integer Template:Deprecated-inline Use page_namespace instead.
    Template:Int page_namespace integer refers to Template:Ll
    Template:Int page_age integer the number of seconds since the first edit (or 0 for new pages).This is reliable, but it tends to be slow; consider using page_id if you don't need much precision.
    Template:Int article_text string Template:Deprecated-inline Use page_title instead.
    Template:Int page_title string
    Template:Int article_prefixedtext string Template:Deprecated-inline Use page_prefixedtitle instead.
    Template:Int page_prefixedtitle string
    Template:Int article_restrictions_edit string Template:Deprecated-inline Use page_restrictions_edit instead.
    Template:Int page_restrictions_edit array of strings
    Template:Int article_restrictions_move string Template:Deprecated-inline Use page_restrictions_move instead.
    Template:Int page_restrictions_move array of strings
    Template:Int article_restrictions_upload string Template:Deprecated-inline Use page_restrictions_upload instead.
    Template:Int page_restrictions_upload array of strings
    Template:Int article_restrictions_create string Template:Deprecated-inline Use page_restrictions_create instead.
    Template:Int page_restrictions_create array of strings
    Template:Int article_recent_contributors array of strings Template:Deprecated-inline Use page_recent_contributors instead.
    Template:Int page_recent_contributors array of strings This tends to be slow (see #Performance).Try to put conditions more likely evaluate to false before this one, to avoid unnecessarily running the query.This value is empty if the user is the only contributor to the page(?), and only scans the last 100 revisions
    Template:Int article_first_contributor string Template:Deprecated-inline Use page_first_contributor instead.
    Template:Int page_first_contributor string This tends to be slow (see #Performance).[4] Try to put conditions more likely evaluate to false before this one, to avoid unnecessarily running the query.

    Variables available for some actions

    Template:Caution

    Description Name Data type Notes
    Template:Int summary string Summaries automatically created by MediaWiki ("New section", "Blanked the page", etc.) are created after the filter checks the edit, so they will never actually catch, even if the debugger shows that they should.[5]
    Template:Int minor_edit string Disabled, and set to false for all entries between 2016 and 2018.[6]
    Template:Int old_wikitext string This variable can be very large.Consider using removed_lines if possible to improve performance.
    Template:Int new_wikitext string This variable can be very large.Consider using added_lines if possible to improve performance.
    Template:Int edit_diff string
    Template:Int edit_diff_pst string This tends to be slow (see #Performance). Checking both added_lines and removed_lines is probably more efficient.[7]
    Template:Int new_size integer
    Template:Int old_size integer
    Template:Int edit_delta integer
    Template:Int added_lines_pst array of strings Useadded_lines if possible, which is more efficient.
    Template:Int added_lines array of strings includes all lines in the final diff that begin with +
    Template:Int removed_lines array of strings
    Template:Int all_links array of strings
    Template:Int old_links array of strings
    Template:Int added_links array of strings This tends to be slow (see #Performance).Consider checking against added_lines first, then check added_links so that fewer edits are slowed down.This follows Template:Ll.Only unique links are added to the array.Changing a link will count as 1 added and 1 removed link.
    Template:Int removed_links array of strings This tends to be slow (see #Performance).Consider checking against removed_lines first, then check removed_links so that fewer edits are slowed down.This follows Template:Ll.Only unique links are added to the array.Changing a link will count as 1 added and 1 removed link.
    Template:Int new_pst string
    Template:Int new_html string This variable can be very large.Consider using added_lines if possible to improve performance.
    Template:Int new_text string This variable can be very large.Consider using added_lines if possible to improve performance.
    Template:Int old_html string Disabled for performance reasons.
    Template:Int old_text string Disabled for performance reasons.
    Template:Int file_sha1 string [2]
    Template:Int file_size integer The file size in bytes[2]
    Template:Int file_width integer The width in pixels[2]
    Template:Int file_height integer The height in pixels[2]
    Template:Int file_bits_per_channel integer The amount of bits per color channel[2]
    Template:Int file_mime string The file MIME type.[2]
    Template:Int file_mediatype string The file media type.[8][2]
    Template:Int moved_to_articleid integer Template:Deprecated-inline Use moved_to_id instead.
    Template:Int moved_to_id integer
    Template:Int moved_to_text string Template:Deprecated-inline Use moved_to_title instead.
    Template:Int moved_to_title string
    Template:Int moved_to_prefixedtext string Template:Deprecated-inline Use moved_to_prefixedtitle instead.
    Template:Int moved_to_prefixedtitle string
    Template:Int moved_to_namespace integer
    Template:Int moved_to_age integer
    Template:Int moved_to_restrictions_edit array of string Same as page_restrictions_edit, but for the target of the move.
    Template:Int moved_to_restrictions_move array of string Same as page_restrictions_move, but for the target of the move.
    Template:Int moved_to_restrictions_upload array of string Same as page_restrictions_upload, but for the target of the move.
    Template:Int moved_to_restrictions_create array of string Same as page_restrictions_create, but for the target of the move.
    Template:Int moved_to_recent_contributors array of strings Same as page_recent_contributors, but for the target of the move.
    Template:Int moved_to_first_contributor string Same as page_first_contributor, but for the target of the move.
    Template:Int moved_from_namespace integer
    Template:Int moved_from_text string Template:Deprecated-inline Use moved_from_title instead.
    Template:Int moved_from_title string
    Template:Int moved_from_prefixedtext string Template:Deprecated-inline Use moved_from_prefixedtitle instead.
    Template:Int moved_from_prefixedtitle string
    Template:Int moved_from_articleid integer Template:Deprecated-inline Use moved_from_id instead.
    Template:Int moved_from_id integer
    Template:Int moved_from_age integer
    Template:Int moved_from_restrictions_edit array of string Same as page_restrictions_edit, but for the page being moved.
    Template:Int moved_from_restrictions_move array of string Same as page_restrictions_move, but for the page being moved.
    Template:Int moved_from_restrictions_upload array of string Same as page_restrictions_upload, but for the page being moved.
    Template:Int moved_from_restrictions_create array of string Same as page_restrictions_create, but for the page being moved.
    Template:Int moved_from_recent_contributors array of strings Same as page_recent_contributors, but for the page being moved.
    Template:Int moved_from_first_contributor string Same as page_first_contributor, but for the page being moved.
    Template:Int accountname string
    Content model of the old revision old_content_model string See Template:Ll for information about content model changes
    Content model of the new revision new_content_model string See Template:Ll for information about content model changes

    Variables from other extensions

     Most of these variables are always set to false when examinating past edits, and may not reflect their actual value at the time the edit was made.See T102944.:

    Description Name Data type Values Added by
    Template:Int global_user_groups array Template:Ll
    Template:Int board_articleid integer Template:Deprecated-inline Use board_id instead. Template:Ll
    Template:Int board_id integer Template:Ll
    Template:Int board_namespace integer refers to Template:Ll Template:Ll
    Template:Int board_text string Template:Deprecated-inline Use board_title instead. Template:Ll
    Template:Int board_title string Template:Ll
    Template:Int board_prefixedtext string Template:Deprecated-inline Use board_prefixedtitle instead. Template:Ll
    Template:Int board_prefixedtitle string Template:Ll
    Template:Int translate_source_text string Template:Ll
    Template:Int translate_target_language string This is the language code, like en for English. Template:Ll
    Template:Int tor_exit_node boolean true if the action comes from a tor exit node. Template:Ll
    Template:Int user_mobile boolean true for mobile users, false otherwise. Template:Ll
    Template:Int user_app boolean true if the user is editing from the mobile app, false otherwise. Template:Ll
    Page views[1] article_views integer Template:Deprecated-inline Use page_views instead. Template:Ll
    Page views[2] page_views integer the amount of page views Template:Ll
    Source page views[3] moved_from_views integer the amount of page views of the source page Template:Ll
    Target page views[4] moved_to_views integer the amount of page views of the target page Template:Ll
    True if this action was performed through a proxy[5] is_proxy integer Whether this action was performed through a proxy Template:Ll
    Whether the IP address is blocked using the stopforumspam.com list[6] sfs_blocked boolean Whether the IP address is blocked using the stopforumspam.com list Template:Ll

    Notes

    When action='move',only the summary,action,timestamp and user_* variables are available.The page_* variables are also available, but the prefix is replaced by moved_from_ and moved_to_, that represent the values of the original article name and the destination one, respectively.For example, moved_from_title and moved_to_title instead of page_title.

    Since MediaWiki 1.28 (gerrit:295254), action='upload' is only used when publishing an upload, and not for uploads to stash.A new action='stashupload' is introduced, which is used for all uploads, including uploads to stash.This behaves like action='upload' used to, and only provides file metadata variables (file_*).Variables related to the page edit, including summary, new_wikitext and several others, are now available for action='upload'.For every file upload, filters may be called with action='stashupload' (for uploads to stash), and are always called with action='upload'; they are not called with action='edit'.

    Filter authors should use action='stashupload' | action='upload' in filter code when a file can be checked based only on the file contents – for example, to reject low-resolution files – and action='upload' only when the wikitext parts of the edit need to be examined too – for example, to reject files with no description.This will allow tools that separate uploading the file and publishing the file (e.g. UploadWizard or upload dialog) to inform the user of the failure before they spend the time filling in the upload details.

    Performance

    As noted in the table above, some of these variables can be very slow.While writing filters, remember that the condition limit is not a good metric of how heavy filters are.For instance, variables like *_recent_contributors or *_links always need a DB query to be computed, while *_pst variables will have to perform parsing of the text, which again is a heavy operation; all these variables should be used very, very carefully.For instance, on Italian Wikipedia it's been observed that, with 135 active filters and an average of 450 used conditions, filters execution time was around 500ms, with peaks reaching 15 seconds.Removing the added_links variable from a single filter, and halving the cases when another filter would use added_lines_pst brought the average execution time to 50ms.More specifically:

    • Use _links variables when you need high accuracy and checking for "http://..." in other variables (for instance, added_lines) could lead to heavy malfunctioning;
    • Use _pst variables when you're really sure that non-PST variables aren't enough.You may also conditionally decide which one to check: if, for instance, you want to examine a signature, check first if added_lines contains ~~~;
    • In general, when dealing with these variables, it's always much better to consume further conditions but avoid computing heavy stuff.In order to achieve this, always put heavy variables as last conditions.

    Last but not least, note that whenever a variable is computed for a given filter, it'll be saved and any other filter will immediately retrieve it.This means that one single filter computing this variable counts more or less as dozens of filters using it.

    Keywords

     Where not specifically stated, keywords cast their operands to strings: The following special keywords are included for often-used functionality:

    • like (or matches) returns true if the left-hand operand matches the glob pattern in the right-hand operand.
    • in returns true if the right-hand operand (a string) contains the left-hand operand.Note:empty strings are not contained in, nor contain, any other string (not even the empty string itself).
    • contains works like in, but with the left and right-hand operands switched.Note:empty strings are not contained in, nor contain, any other string (not even the empty string itself).
    • rlike (or regex) and irlike return true if the left-hand operand matches (contains) the regex pattern in the right-hand operand (irlike is case insensitive).

    The system uses PCRE.The only PCRE option enabled is PCRE_UTF8 (modifier u in PHP); for irlike both PCRE_CASELESS and PCRE_UTF8 are enabled (modifier iu).

    • if ... then ... end
    • if ... then ... else ... end
    • ... ? ... : ...
    • true,false,null

    Examples

    Code Result Comment
    "1234" like "12?4" True
    "1234" like "12*" True
    "foo" in "foobar" True
    "foobar" contains "foo" True
    "o" in ["foo", "bar"] True Due to the string cast
    "foo" regex "\w+" True
    "a\b" regex "a\\\\b" True To look for the escape character backslash using regex you need to use either four backslashes or two \x5C. (Either works fine.)
    "a\b" regex "a\x5C\x5Cb" True

    Functions

    A number of built-in functions are included to ease some common issues.They are executed in the general format functionName( arg1, arg2, arg3 ), and can be used in place of any literal or variable.Its arguments can be given as literals, variables, or even other functions.

    name description
    lcase Returns the argument converted to lower case.
    ucase Returns the argument converted to upper case.
    length Returns the length of the string given as the argument.If the argument is an array, returns its number of elements.
    string Casts to string data type.If the argument is an array, implodes it with linebreaks.
    int Casts to integer data type.
    float Casts to floating-point data type.
    bool Casts to boolean data type.
    norm Equivalent to rmwhitespace(rmspecials(rmdoubles(ccnorm(arg1)))).
    ccnorm Normalises confusable/similar characters in the argument, and returns a canonical form.A list of characters and their replacements can be found on git, e.g. ccnorm( "Eeèéëēĕėęě3ƐƷ" ) === "EEEEEEEEEEEEE".[9] The output of this function is always uppercase.
    ccnorm_contains_any Normalises confusable/similar characters in the arguments, and returns true if the first string contains any string from the following arguments (unlimited number of arguments, logic OR mode).A list of characters and their replacements can be found on git.
    ccnorm_contains_all Normalises confusable/similar characters in the arguments, and returns true if the first string contains every string from the following arguments (unlimited number of arguments, logic AND mode).A list of characters and their replacements can be found on git.
    specialratio Returns the number of non-alphanumeric characters divided by the total number of characters in the argument.
    rmspecials Removes any special characters in the argument, and returns the result. (Equivalent to s/[^\p{L}\p{N}]//g.)
    rmdoubles Removes repeated characters in the argument, and returns the result.
    rmwhitespace Removes whitespace (spaces, tabs, newlines).
    count Returns the number of times the needle (first string) appears in the haystack (second string).If only one argument is given, splits it by commas and returns the number of segments.
    rcount Similar to count but the needle uses a regular expression instead.Can be made case-insensitive by letting the regular expression start with "(?i)".Please note that, for plain strings, this function can be up to 50 times slower than count[10], so use that one when possible.
    get_matches Template:MW version-inline Looks for matches of the regex needle (first string) in the haystack (second string).Returns an array where the 0 element is the whole match and every [n] element is the match of the n'th capturing group of the needle.Can be made case-insensitive by letting the regular expression start with "(?i)".If a capturing group didn't match, that array position will take value of false.
    ip_in_range Returns true if user's IP (first string) matches the specified IP range (second string, in CIDR notation).Only works for anonymous users.Supports both IPv4 and IPv6 addresses.
    contains_any Returns true if the first string contains any string from the following arguments (unlimited number of arguments in logic OR mode).If the first argument is an array, it gets casted to string.
    contains_all Returns true if the first string contains every string from the following arguments (unlimited number of arguments in logic AND mode).If the first argument is an array, it gets casted to string.
    equals_to_any Returns true if the first argument is identical (===) to any of the following ones (unlimited number of arguments).Basically, equals_to_any(a, b, c) is the same as a===b | a===c, but more compact and saves conditions.
    substr Returns the portion of the first string, by offset from the second argument (starts at 0) and maximum length from the third argument (optional).
    strlen Same as length.
    strpos Returns the numeric position of the first occurrence of needle (second string) in the haystack (first string), starting from offset from the third argument (optional, default is 0).This function may return 0 when the needle is found at the begining of the haystack, so it might be misinterpreted as false value by another comparative operator.The better way is to use === or !== for testing whether it is found.
    str_replace Replaces all occurrences of the search string with the replacement string.The function takes 3 arguments in the following order: text to perform the search on, text to find, replacement text.
    rescape Returns the argument with some characters preceded with the escape character "\", so that the string can be used in a regular expression without those characters having a special meaning.
    set Sets a variable (first string) with a given value (second argument) for further use in the filter.Another syntax: name := value.
    set_var Same as set.

    Examples

    Code Result Comment
    length( "Wikipedia" ) 9
    lcase( "WikiPedia" ) wikipedia
    ccnorm( "w1k1p3d14" ) WIKIPEDIA ccnorm output is always uppercase
    ccnorm( "ωɨƙɩᑭƐƉ1α" ) WIKIPEDIA
    ccnorm_contains_any( "w1k1p3d14", "wiKiP3D1A", "foo", "bar" ) true
    ccnorm_contains_any( "w1k1p3d14", "foo", "bar", "baz" ) false
    ccnorm_contains_any( "w1k1p3d14 is 4w3s0me", "bar", "baz", "some" ) true
    ccnorm( "ìíîïĩїį!ľ₤ĺľḷĿ" ) IIIIIII!LLLLLL
    norm( "!!ω..ɨ..ƙ..ɩ..ᑭᑭ..Ɛ.Ɖ@@1%%α!!" ) WIKIPEDAIA
    norm( "F00 B@rr" ) FOBAR norm removes whitespace, special characters and duplicates, then uses ccnorm
    rmdoubles( "foobybboo" ) fobybo
    specialratio( "Wikipedia!" ) 0.1
    count( "foo", "foofooboofoo" ) 3
    count( "foo,bar,baz" ) 3
    rmspecials( "FOOBAR!!1" ) FOOBAR1
    rescape( "abc* (def)" ) abc\* \(def\)
    str_replace( "foobarbaz", "bar", "-" ) foo-baz
    ip_in_range( "127.0.10.0", "127.0.0.0/12" ) true
    contains_any( "foobar", "x", "y", "f" ) true
    get_matches( "(foo?ba+r) is (so+ good)", "fobaaar is soooo good to eat" ) ['fobaaar is soooo good', 'fobaaar', 'soooo good']

    Order of operations

    Operations are generally done left-to-right, but there is an order to which they are resolved.As soon as the filter fails one of the conditions, it will stop checking the rest of them (due to short-circuit evaluation) and move on to the next filter.The evaluation order is:

    1. Anything surrounded by parentheses (( and )) is evaluated as a single unit.
    2. Turning variables/literals into their respective data. (e.g.,page_namespace to 0)
    3. Function calls (norm,lcase, etc.)
    4. Unary + and - (defining positive or negative value, e.g.-1234, +1234)
    5. Keywords (in, rlike, etc.)
    6. Boolean inversion (!x)
    7. Exponentiation (2**3 → 8)
    8. Multiplication-related (multiplication, division, modulo)
    9. Addition and subtraction (3-2 → 1)
    10. Comparisons. (<, >, ==)
    11. Boolean operations. (&, |, ^)

    Examples

    • A & B | C is equivalent to (A & B) | C, not to A & (B | C).In particular, both false & true | true and false & false | true evaluates to true.
    • A | B & C is equivalent to (A | B) & C, not to A | (B & C).In particular, both true | true & false and true | false & false evaluates to false.

    Condition counting

    The condition limit is (more or less) tracking the number of comparison operators + number of function calls entered.

    Further explanation on how to reduce conditions used can be found at Template:Ll.

    Exclusions

    Although the AbuseFilter examine function will identify "rollback" actions as edits, the AbuseFilter will not evaluate rollback actions for matching.[11]

    Useful links

    Notes

    1. Comparing arrays to other types will always return false, except for the example above
    2. 2.0 2.1 2.2 2.3 2.4 2.5 2.6 2.7 The only variables currently available for file uploads (action='upload') are user_*, page_*, file_sha1, file_size, file_mime, file_mediatype, file_width, file_height, file_bits_per_channel (the last five were only added since the release for MediaWiki 1.27 gerrit:281503).All the file_* variables are unavailable for other actions (including action='edit').
    3. Since MediaWiki 1.28 (gerrit:295254)
    4. Several filters (12) that use this variable have showed up in the AbuseFilterSlow Grafana dashboard (requires logstash access to view).Moving this variable to towards the end of the filter seemed to help.
    5. See phabricator:T191722
    6. Deprecated with this commit and disabled with this one.
    7. Some filters using this variable have showed up in the AbuseFilterSlow Grafana dashboard (example, requires logstash access).For instance, instead of using "text" in edit_diff_pst (or even edit_diff), consider something like "text" in added_lines & !("text" in removed_lines)
    8. See the source code for a list of types.
    9. Be aware of phab:T27619.You can use Special:AbuseFilter/tools to evaluate ccnorm( "your string" ) to see which characters are transformed.
    10. https://3v4l.org/S6IGP
    11. T24713 - rollback not matched by AF