Add RFC 2396

This adds the ABNF from RFC 2396, the original
specification of the URI syntax from 1998.

Please note, that RFC 2396 was succeeded by
RFC 3986 in 2005, which introduced concepts like
IPv6 to the URI syntax specification.

AUTHORS

@@ -1,2 +1,3 @@
 Marko Ristin ([email protected], [email protected], [email protected]) for Zurich University of Applied Sciences (ZHAW)
 Oliver Steensen-Bech Haagh ([email protected]) for Digital Maritime Consultancy ApS
+Sebastian Heppner ([email protected], [email protected]) for RWTH Aachen University

test_data/nested-python/rfc2396/expected.py

@@ -0,0 +1,49 @@
+alphanum = '[a-zA-Z0-9]'
+mark = "[\\-\\-.!~*'()]"
+unreserved = f'({alphanum}|{mark})'
+hex = (
+    '([0-9]|[aA]|[bB]|[cC]|[dD]|[eE]|[fF]|[aA]|[bB]|[cC]|[dD]|[e'
+    'E]|[fF])'
+)
+escaped = f'%{hex}{hex}'
+pchar = f'({unreserved}|{escaped}|[:@&=+$,])'
+param = f'({pchar})*'
+segment = f'({pchar})*(;{param})*'
+path_segments = f'{segment}(/{segment})*'
+abs_path = f'/{path_segments}'
+scheme = '[a-zA-Z][a-zA-Z0-9+\\-.]*'
+userinfo = f'({unreserved}|{escaped}|[;:&=+$,])*'
+domainlabel = f'({alphanum}|{alphanum}({alphanum}|-)*{alphanum})'
+toplabel = f'([a-zA-Z]|[a-zA-Z]({alphanum}|-)*{alphanum})'
+hostname = f'({domainlabel}\\.)*{toplabel}(\\.)?'
+ipv4address = '[0-9]+\\.[0-9]+\\.[0-9]+\\.[0-9]+'
+host = f'({hostname}|{ipv4address})'
+port = '[0-9]*'
+hostport = f'{host}(:{port})?'
+server = f'(({userinfo}@)?{hostport})?'
+reg_name = f'({unreserved}|{escaped}|[$,;:@&=+])+'
+authority = f'({server}|{reg_name})'
+net_path = f'//{authority}({abs_path})?'
+reserved = '[;/?:@&=+$,]'
+uric = f'({reserved}|{unreserved}|{escaped})'
+query = f'({uric})*'
+hier_part = f'({net_path}|{abs_path})(\\?{query})?'
+uric_no_slash = f'({unreserved}|{escaped}|[;?:@&=+$,])'
+opaque_part = f'{uric_no_slash}({uric})*'
+absoluteuri = f'{scheme}:({hier_part}|{opaque_part})'
+fragment = f'({uric})*'
+lowalpha = (
+    '([aA]|[bB]|[cC]|[dD]|[eE]|[fF]|[gG]|[hH]|[iI]|[jJ]|[k'
+    'K]|[lL]|[mM]|[nN]|[oO]|[pP]|[qQ]|[rR]|[sS]|[tT]|[uU]|[v'
+    'V]|[wW]|[xX]|[yY]|[zZ])'
+)
+path = f'({abs_path}|{opaque_part})?'
+rel_segment = f'({unreserved}|{escaped}|[;@&=+$,])+'
+rel_path = f'{rel_segment}({abs_path})?'
+relativeuri = f'({net_path}|{abs_path}|{rel_path})(\\?{query})?'
+upalpha = (
+    '([aA]|[bB]|[cC]|[dD]|[eE]|[fF]|[gG]|[hH]|[iI]|[jJ]|[kK]|'
+    '[lL]|[mM]|[nN]|[oO]|[pP]|[qQ]|[rR]|[sS]|[tT]|[uU]|[vV]|'
+    '[wW]|[xX]|[yY]|[zZ])'
+)
+uri_reference = f'({absoluteuri}|{relativeuri})?(\\#{fragment})?'

test_data/nested-python/rfc2396/grammar.abnf

@@ -0,0 +1,82 @@
+; From: https://www.ietf.org/rfc/rfc2396.txt
+; Note that RFC 3986 is a newer version of the URI standard
+
+alpha         = lowalpha / upalpha
+
+lowalpha      = "a" / "b" / "c" / "d" / "e" / "f" / "g" / "h" / "i" /
+                "j" / "k" / "l" / "m" / "n" / "o" / "p" / "q" / "r" /
+                "s" / "t" / "u" / "v" / "w" / "x" / "y" / "z"
+
+upalpha       = "A" / "B" / "C" / "D" / "E" / "F" / "G" / "H" / "I" /
+                "J" / "K" / "L" / "M" / "N" / "O" / "P" / "Q" / "R" /
+                "S" / "T" / "U" / "V" / "W" / "X" / "Y" / "Z"
+
+digit         = "0" / "1" / "2" / "3" / "4" / "5" / "6" / "7" /
+                "8" / "9"
+
+alphanum      = alpha / digit
+
+uric          = reserved / unreserved / escaped
+
+reserved      = ";" / "/" / "?" / ":" / "@" / "&" / "=" / "+" /
+                "$" / ","
+
+unreserved    = alphanum / mark
+
+mark          = "-" / "-" / "." / "!" / "~" / "*" / "'" / "(" / ")"
+
+escaped       = "%" hex hex
+
+hex           = digit / "A" / "B" / "C" / "D" / "E" / "F" /
+                        "a" / "b" / "c" / "d" / "e" / "f"
+
+absoluteURI   = scheme ":" ( hier-part / opaque-part )
+
+hier-part     = ( net-path / abs-path ) [ "?" query ]
+net-path      = "//" authority [ abs-path ]
+abs-path      = "/"  path-segments
+
+opaque-part   = uric-no-slash *uric
+
+uric-no-slash = unreserved / escaped / ";" / "?" / ":" / "@" /
+                "&" / "=" / "+" / "$" / ","
+
+scheme        = alpha *( alpha / digit / "+" / "-" / "." )
+
+authority     = server / reg-name
+
+reg-name      = 1*( unreserved / escaped / "$" / "," /
+                    ";" / ":" / "@" / "&" / "=" / "+" )
+
+server        = [ [ userinfo "@" ] hostport ]
+
+userinfo      = *( unreserved / escaped /
+                   ";" / ":" / "&" / "=" / "+" / "$" / "," )
+
+hostport      = host [ ":" port ]
+host          = hostname / IPv4address
+hostname      = *( domainlabel "." ) toplabel [ "." ]
+domainlabel   = alphanum / alphanum *( alphanum / "-" ) alphanum
+toplabel      = alpha / alpha *( alphanum / "-" ) alphanum
+
+IPv4address   = 1*digit "." 1*digit "." 1*digit "." 1*digit
+port          = *digit
+
+path          = [ abs-path / opaque-part ]
+path-segments = segment *( "/" segment )
+segment       = *pchar *( ";" param )
+param         = *pchar
+pchar         = unreserved / escaped /
+                ":" / "@" / "&" / "=" / "+" / "$" / ","
+
+query         = *uric
+
+URI-reference = [ absoluteURI / relativeURI ] [ "#" fragment ]
+
+fragment      = *uric
+
+relativeURI   = ( net-path / abs-path / rel-path ) [ "?" query ]
+
+rel-path      = rel-segment [ abs-path ]
+rel-segment   = 1*( unreserved / escaped /
+                    ";" / "@" / "&" / "=" / "+" / "$" / "," )