/usr/lib/gcc/x86_64-linux-gnu/6/include/d/std/regex/internal/generator.d is in libgphobos-6-dev 6.4.0-17ubuntu1.
This file is owned by root:root, with mode 0o644.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 | /*
Generators - components that generate strings for a given regex pattern.
For the moment undocumented, and is subject to change.
*/
module std.regex.internal.generator;
/*
Useful utility for self-testing, an infinite range of string samples
that _have_ to match given compiled regex.
Caveats: supports only a simple subset of bytecode.
*/
@trusted private struct SampleGenerator(Char)
{
import std.regex.internal.ir;
import std.array, std.format, std.utf, std.random;
Regex!Char re;
Appender!(char[]) app;
uint limit, seed;
Xorshift gen;
//generator for pattern r, with soft maximum of threshold elements
//and a given random seed
this(ref Regex!Char r, uint threshold, uint randomSeed)
{
re = r;
limit = threshold;
seed = randomSeed;
app = appender!(Char[])();
compose();
}
uint rand(uint x)
{
uint r = gen.front % x;
gen.popFront();
return r;
}
void compose()
{
uint pc = 0, counter = 0, dataLenOld = uint.max;
for(;;)
{
switch(re.ir[pc].code)
{
case IR.Char:
formattedWrite(app,"%s", cast(dchar)re.ir[pc].data);
pc += IRL!(IR.Char);
break;
case IR.OrChar:
uint len = re.ir[pc].sequence;
formattedWrite(app, "%s", cast(dchar)re.ir[pc + rand(len)].data);
pc += len;
break;
case IR.CodepointSet:
case IR.Trie:
auto set = re.charsets[re.ir[pc].data];
auto x = rand(cast(uint)set.byInterval.length);
auto y = rand(set.byInterval[x].b - set.byInterval[x].a);
formattedWrite(app, "%s", cast(dchar)(set.byInterval[x].a+y));
pc += IRL!(IR.CodepointSet);
break;
case IR.Any:
uint x;
do
{
x = rand(0x11_000);
}while(x == '\r' || x == '\n' || !isValidDchar(x));
formattedWrite(app, "%s", cast(dchar)x);
pc += IRL!(IR.Any);
break;
case IR.GotoEndOr:
pc += IRL!(IR.GotoEndOr)+re.ir[pc].data;
assert(re.ir[pc].code == IR.OrEnd);
goto case;
case IR.OrEnd:
pc += IRL!(IR.OrEnd);
break;
case IR.OrStart:
pc += IRL!(IR.OrStart);
goto case;
case IR.Option:
uint next = pc + re.ir[pc].data + IRL!(IR.Option);
uint nOpt = 0;
//queue next Option
while(re.ir[next].code == IR.Option)
{
nOpt++;
next += re.ir[next].data + IRL!(IR.Option);
}
nOpt++;
nOpt = rand(nOpt);
for(;nOpt; nOpt--)
{
pc += re.ir[pc].data + IRL!(IR.Option);
}
assert(re.ir[pc].code == IR.Option);
pc += IRL!(IR.Option);
break;
case IR.RepeatStart:case IR.RepeatQStart:
pc += IRL!(IR.RepeatStart)+re.ir[pc].data;
goto case IR.RepeatEnd;
case IR.RepeatEnd:
case IR.RepeatQEnd:
uint len = re.ir[pc].data;
uint step = re.ir[pc+2].raw;
uint min = re.ir[pc+3].raw;
if(counter < min)
{
counter += step;
pc -= len;
break;
}
uint max = re.ir[pc+4].raw;
if(counter < max)
{
if(app.data.length < limit && rand(3) > 0)
{
pc -= len;
counter += step;
}
else
{
counter = counter%step;
pc += IRL!(IR.RepeatEnd);
}
}
else
{
counter = counter%step;
pc += IRL!(IR.RepeatEnd);
}
break;
case IR.InfiniteStart, IR.InfiniteQStart:
pc += re.ir[pc].data + IRL!(IR.InfiniteStart);
goto case IR.InfiniteEnd; //both Q and non-Q
case IR.InfiniteEnd:
case IR.InfiniteQEnd:
uint len = re.ir[pc].data;
if(app.data.length == dataLenOld)
{
pc += IRL!(IR.InfiniteEnd);
break;
}
dataLenOld = cast(uint)app.data.length;
if(app.data.length < limit && rand(3) > 0)
pc = pc - len;
else
pc = pc + IRL!(IR.InfiniteEnd);
break;
case IR.GroupStart, IR.GroupEnd:
pc += IRL!(IR.GroupStart);
break;
case IR.Bol, IR.Wordboundary, IR.Notwordboundary:
case IR.LookaheadStart, IR.NeglookaheadStart, IR.LookbehindStart, IR.NeglookbehindStart:
default:
return;
}
}
}
@property Char[] front()
{
return app.data;
}
@property empty(){ return false; }
void popFront()
{
app.shrinkTo(0);
compose();
}
}
unittest
{
import std.range, std.regex;
auto re = regex(`P[a-z]{3,}q`);
auto gen = SampleGenerator!char(re, 20, 3141592);
static assert(isInputRange!(typeof(gen)));
//@@@BUG@@@ somehow gen.take(1_000) doesn't work
foreach(v; take(gen, 1_000))
assert(v.match(re));
}
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