These are miscellaneous tests of my own division.
 
hello world
The quick brown fox jumps over the lazy doggerel.txt
well  ?  then  	.		 how  about     this  ?
Once upon a time there was a file name sanitiser; it was a good file name sanitiser, and never exposed security vulnerabilities to the World. “It’s a dangerous place,” its grandf.“If a wolf should come out of the forest, then what would you do?”
(Some Peter and the Wolf snuck in there.)
.hidden
C:\WINDOWS\system32\driver\etc\hosts
%WINDIR%\system32\driver\etc\hosts
Kinda funny how Windows has a /etc/hosts.
.
.
.
.
/././././././
.
I’m basically just typing random stuff here.
OK, time for some more serious stuff.
_
For Unicode paths, some file systems limit paths to roughly 255 UTF-8 code units, others to roughly 255 UTF-16 code units. UTF-8 is the tighter of these restrictions in all circumstances: UTF-16 uses one code unit until U+FF.Now then: one-byte characters:
# One-byte characters:
123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345
12345678901234567890.abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz
123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678.abcdefghijklmnopqrstuvwxyz
# Two-byte characters:
áɓçđéƒɠɦïķáɓçđéƒɠɦïķáɓçđéƒɠɦïķáɓçđéƒɠɦïķáɓçđéƒɠɦïķáɓçđéƒɠɦïķáɓçđéƒɠɦïķáɓçđéƒɠɦïķáɓçđéƒɠɦïķáɓçđéƒɠɦïķáɓçđéƒɠɦïķáɓçđéƒɠɦïķáɓçđéƒɠ
áɓç.°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³
áɓçđéƒɠ.°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³
áɓçđéƒɠɦïķá.°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³°¹²³
áɓçđéƒɠɦïķáɓçđéƒɠɦïķáɓçđéƒɠɦïķáɓçđéƒɠɦïķáɓçđéƒɠɦïķáɓçđéƒɠɦïķáɓçđéƒɠɦïķáɓçđéƒɠɦïķáɓçđéƒɠɦïķáɓçđéƒɠɦïķáɓçđéƒɠɦïķáɓçđéƒɠɦïķáɓç.°¹²³
# Three-byte characters:
‐‑‒–—―‖‗‘’‚‛“”„‟†‡•‣․‥…‧‐‑‒–—―‖‗‘’‚‛“”„‟†‡•‣․‥…‧‐‑‒–—―‖‗‘’‚‛“”„‟†‡•‣․‥…‧‐‑‒–—―‖‗‘’‚‛“
‐‑‒–—.₁₂₃₄₅₆₇₈₉₀₁₂₃₄₅₆₇₈₉₀₁₂₃₄₅₆₇₈₉₀₁₂₃₄₅₆₇₈₉₀₁₂₃₄₅₆₇₈₉₀₁₂₃₄₅₆₇₈₉₀₁₂₃₄₅₆₇₈₉₀₁₂₃₄₅₆₇₈₉
‐‑‒–—―‖‗‘’‚‛“”„‟†‡•‣․‥…‧‐‑‒–—―‖‗‘’‚‛“”„‟†‡•‣․‥…‧‐‑‒–—―‖‗‘’‚‛“”„‟†‡•‣․‥…‧‐‑.₁₂₃₄₅₆₇₈₉₀
# Four-byte characters:
𐀀𐀁𐀂𐀃𐀄𐀅𐀆𐀇𐀈𐀉𐀊𐀋𐀍𐀎𐀏𐀐𐀑𐀒𐀓𐀔𐀕𐀖𐀗𐀘𐀙𐀚𐀛𐀜𐀝𐀞𐀟𐀠𐀡𐀢𐀣𐀤𐀥𐀦𐀨𐀩𐀪𐀫𐀬𐀭𐀮𐀯𐀰𐀱𐀲𐀳𐀴𐀵𐀶𐀷𐀸𐀹𐀺𐀼𐀽𐀿𐁀𐁁𐁂
𐀀𐀁𐀂𐀃𐀄𐀅𐀆.𐂀𐂁𐂂𐂃𐂄𐂅𐂆𐂇𐂈𐂉𐂊𐂋𐂌𐂍𐂀𐂁𐂂𐂃𐂄𐂅𐂆𐂇𐂈𐂉𐂊𐂋𐂌𐂍𐂀𐂁𐂂𐂃𐂄𐂅𐂆𐂇𐂈𐂉𐂊𐂋𐂌𐂍𐂀𐂁𐂂𐂃𐂄𐂅𐂆𐂇𐂈𐂉𐂊𐂋𐂌𐂍
𐀀𐀁𐀂𐀃𐀄𐀅𐀆𐀇𐀈𐀉𐀊𐀋𐀍𐀎𐀏𐀐𐀑𐀒𐀓𐀔𐀕𐀖𐀗𐀘𐀙𐀚𐀛𐀜𐀝𐀞𐀟𐀠𐀡𐀢𐀣𐀤𐀥𐀦𐀨𐀩𐀪𐀫𐀬𐀭𐀮𐀯𐀰𐀱𐀲.𐂀𐂁𐂂𐂃𐂄𐂅𐂆𐂇𐂈𐂉𐂊𐂋𐂌𐂍
_
abcdef.ghij
abcde.fghij
AUX.abcdef
lpT7.abcdef
cOm6.abcdef
CON
aux.h
Lpt1.exe
xyz
nül
COM1.jpg.png
_
Some sanitisers try stripping out ZWSP (​), which can be used as a fingerprinting vector and has no particularly legitimate purpose in a file name; I’m not, because removing it doesn’t solve the fingerprinting risk, as you can use ZWNJ and ZWJ (.)