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Diffstat (limited to 'lib/pure/punycode.nim')
| -rw-r--r-- | lib/pure/punycode.nim | 209 |
1 files changed, 0 insertions, 209 deletions
diff --git a/lib/pure/punycode.nim b/lib/pure/punycode.nim deleted file mode 100644 index 49e46496e..000000000 --- a/lib/pure/punycode.nim +++ /dev/null @@ -1,209 +0,0 @@ -# -# -# Nim's Runtime Library -# (c) Copyright 2016 Andreas Rumpf -# -# See the file "copying.txt", included in this -# distribution, for details about the copyright. -# - -## Implements a representation of Unicode with the limited -## ASCII character subset. - -import strutils -import unicode - -# issue #3045 - -const - Base = 36 - TMin = 1 - TMax = 26 - Skew = 38 - Damp = 700 - InitialBias = 72 - InitialN = 128 - Delimiter = '-' - -type - PunyError* = object of ValueError - -func decodeDigit(x: char): int {.raises: [PunyError].} = - if '0' <= x and x <= '9': - result = ord(x) - (ord('0') - 26) - elif 'A' <= x and x <= 'Z': - result = ord(x) - ord('A') - elif 'a' <= x and x <= 'z': - result = ord(x) - ord('a') - else: - raise newException(PunyError, "Bad input") - -func encodeDigit(digit: int): Rune {.raises: [PunyError].} = - if 0 <= digit and digit < 26: - result = Rune(digit + ord('a')) - elif 26 <= digit and digit < 36: - result = Rune(digit + (ord('0') - 26)) - else: - raise newException(PunyError, "internal error in punycode encoding") - -func isBasic(c: char): bool = ord(c) < 0x80 -func isBasic(r: Rune): bool = int(r) < 0x80 - -func adapt(delta, numPoints: int, first: bool): int = - var d = if first: delta div Damp else: delta div 2 - d += d div numPoints - var k = 0 - while d > ((Base-TMin)*TMax) div 2: - d = d div (Base - TMin) - k += Base - result = k + (Base - TMin + 1) * d div (d + Skew) - -func encode*(prefix, s: string): string {.raises: [PunyError].} = - ## Encode a string that may contain Unicode. - ## Prepend `prefix` to the result - result = prefix - var (d, n, bias) = (0, InitialN, InitialBias) - var (b, remaining) = (0, 0) - for r in s.runes: - if r.isBasic: - # basic Ascii character - inc b - result.add($r) - else: - # special character - inc remaining - - var h = b - if b > 0: - result.add(Delimiter) # we have some Ascii chars - while remaining != 0: - var m: int = high(int32) - for r in s.runes: - if m > int(r) and int(r) >= n: - m = int(r) - d += (m - n) * (h + 1) - if d < 0: - raise newException(PunyError, "invalid label " & s) - n = m - for r in s.runes: - if int(r) < n: - inc d - if d < 0: - raise newException(PunyError, "invalid label " & s) - continue - if int(r) > n: - continue - var q = d - var k = Base - while true: - var t = k - bias - if t < TMin: - t = TMin - elif t > TMax: - t = TMax - if q < t: - break - result.add($encodeDigit(t + (q - t) mod (Base - t))) - q = (q - t) div (Base - t) - k += Base - result.add($encodeDigit(q)) - bias = adapt(d, h + 1, h == b) - d = 0 - inc h - dec remaining - inc d - inc n - -func encode*(s: string): string {.raises: [PunyError].} = - ## Encode a string that may contain Unicode. Prefix is empty. - result = encode("", s) - -func decode*(encoded: string): string {.raises: [PunyError].} = - ## Decode a Punycode-encoded string - var - n = InitialN - i = 0 - bias = InitialBias - var d = rfind(encoded, Delimiter) - var output: seq[Rune] - - if d > 0: - # found Delimiter - for j in 0..<d: - var c = encoded[j] # char - if not c.isBasic: - raise newException(PunyError, "Encoded contains a non-basic char") - output.add(Rune(c)) # add the character - inc d - else: - d = 0 # set to first index - - while (d < len(encoded)): - var oldi = i - var w = 1 - var k = Base - while true: - if d == len(encoded): - raise newException(PunyError, "Bad input: " & encoded) - var c = encoded[d]; inc d - var digit = int(decodeDigit(c)) - if digit > (high(int32) - i) div w: - raise newException(PunyError, "Too large a value: " & $digit) - i += digit * w - var t: int - if k <= bias: - t = TMin - elif k >= bias + TMax: - t = TMax - else: - t = k - bias - if digit < t: - break - w *= Base - t - k += Base - bias = adapt(i - oldi, len(output) + 1, oldi == 0) - - if i div (len(output) + 1) > high(int32) - n: - raise newException(PunyError, "Value too large") - - n += i div (len(output) + 1) - i = i mod (len(output) + 1) - insert(output, Rune(n), i) - inc i - - result = $output - -runnableExamples: - static: - block: - doAssert encode("") == "" - doAssert encode("a") == "a-" - doAssert encode("A") == "A-" - doAssert encode("3") == "3-" - doAssert encode("-") == "--" - doAssert encode("--") == "---" - doAssert encode("abc") == "abc-" - doAssert encode("London") == "London-" - doAssert encode("Lloyd-Atkinson") == "Lloyd-Atkinson-" - doAssert encode("This has spaces") == "This has spaces-" - doAssert encode("ü") == "tda" - doAssert encode("München") == "Mnchen-3ya" - doAssert encode("Mnchen-3ya") == "Mnchen-3ya-" - doAssert encode("München-Ost") == "Mnchen-Ost-9db" - doAssert encode("Bahnhof München-Ost") == "Bahnhof Mnchen-Ost-u6b" - block: - doAssert decode("") == "" - doAssert decode("a-") == "a" - doAssert decode("A-") == "A" - doAssert decode("3-") == "3" - doAssert decode("--") == "-" - doAssert decode("---") == "--" - doAssert decode("abc-") == "abc" - doAssert decode("London-") == "London" - doAssert decode("Lloyd-Atkinson-") == "Lloyd-Atkinson" - doAssert decode("This has spaces-") == "This has spaces" - doAssert decode("tda") == "ü" - doAssert decode("Mnchen-3ya") == "München" - doAssert decode("Mnchen-3ya-") == "Mnchen-3ya" - doAssert decode("Mnchen-Ost-9db") == "München-Ost" - doAssert decode("Bahnhof Mnchen-Ost-u6b") == "Bahnhof München-Ost" |