Merge branch 'araq-strings-v1' into devel

changelog.md

@@ -83,6 +83,9 @@
 
 - ``nil`` for strings/seqs is finally gone. Instead the default value for
   these is ``"" / @[]``.
+- Accessing the binary zero terminator in Nim's native strings
+  is now invalid. Internally a Nim string still has the trailing zero for
+  zero-copy interoperability with ``cstring``.
 
 ### Tool changes
 

doc/manual.rst

@@ -1471,7 +1471,7 @@ mysterious crashes.
 
 **Note**: The example only works because the memory is initialized to zero
 (``alloc0`` instead of ``alloc`` does this): ``d.s`` is thus initialized to
-``nil`` which the string assignment can handle. One needs to know low level
+binary zero which the string assignment can handle. One needs to know low level
 details like this when mixing garbage collected data with unmanaged memory.
 
 .. XXX finalizers for traced objects
@@ -2512,8 +2512,8 @@ char                            '\\0'
 bool                            false
 ref or pointer type             nil
 procedural type                 nil
-sequence                        nil (*not* ``@[]``)
-string                          nil (*not* "")
+sequence                        ``@[]``
+string                          ``""``
 tuple[x: A, y: B, ...]          (default(A), default(B), ...)
                                 (analogous for objects)
 array[0..., T]                  [default(T), ...]
@@ -4270,7 +4270,7 @@ therefore very useful for type specialization within generic code:
     Table[Key, Value] = object
       keys: seq[Key]
       values: seq[Value]
-      when not (Key is string): # nil value for strings used for optimization
+      when not (Key is string): # empty value for strings used for optimization
         deletedKeys: seq[bool]
 
 
@@ -7434,8 +7434,8 @@ code generation directly, but their presence can be detected by macros.
 Custom pragmas are defined using templates annotated with pragma ``pragma``:
 
 .. code-block:: nim
-  template dbTable(name: string, table_space: string = nil) {.pragma.}
-  template dbKey(name: string = nil, primary_key: bool = false) {.pragma.}
+  template dbTable(name: string, table_space: string = "") {.pragma.}
+  template dbKey(name: string = "", primary_key: bool = false) {.pragma.}
   template dbForeignKey(t: typedesc) {.pragma.}
   template dbIgnore {.pragma.}
 

doc/tut1.rst

@@ -960,11 +960,7 @@ enforced. For example, when reading strings from binary files, they are merely
 a sequence of bytes. The index operation ``s[i]`` means the i-th *char* of
 ``s``, not the i-th *unichar*.
 
-String variables are initialized with a special value, called ``nil``. However,
-most string operations cannot deal with ``nil`` (leading to an exception being
-raised) for performance reasons. It is best to use empty strings ``""``
-rather than ``nil`` as the *empty* value. But ``""`` often creates a string
-object on the heap, so there is a trade-off to be made here.
+String variables are initialized with the empty strings ``""``.
 
 
 Integers
@@ -1309,11 +1305,7 @@ Example:
     x: seq[int] # a reference to a sequence of integers
   x = @[1, 2, 3, 4, 5, 6] # the @ turns the array into a sequence allocated on the heap
 
-Sequence variables are initialized with ``nil``. However, most sequence
-operations cannot deal with ``nil`` (leading to an exception being
-raised) for performance reasons. Thus one should use empty sequences ``@[]``
-rather than ``nil`` as the *empty* value. But ``@[]`` creates a sequence
-object on the heap, so there is a trade-off to be made here.
+Sequence variables are initialized with ``@[]``.
 
 The ``for`` statement can be used with one or two variables when used with a
 sequence. When you use the one variable form, the variable will hold the value
@@ -1355,11 +1347,9 @@ type does not matter.
 .. code-block:: nim
     :test: "nim c $1"
   var
-    fruits:   seq[string]       # reference to a sequence of strings that is initialized with 'nil'
+    fruits:   seq[string]       # reference to a sequence of strings that is initialized with '@[]'
     capitals: array[3, string]  # array of strings with a fixed size
 
-  fruits = @[]                  # creates an empty sequence on the heap that will be referenced by 'fruits'
-
   capitals = ["New York", "London", "Berlin"]   # array 'capitals' allows assignment of only three elements
   fruits.add("Banana")          # sequence 'fruits' is dynamically expandable during runtime
   fruits.add("Mango")
@@ -1691,7 +1681,7 @@ rules apply:
   write(stdout, x(3))   # no error: A.x is called
   write(stdout, x(""))  # no error: B.x is called
 
-  proc x*(a: int): string = nil
+  proc x*(a: int): string = discard
   write(stdout, x(3))   # ambiguous: which `x` is to call?
 
 

examples/httpserver2.nim

@@ -107,7 +107,7 @@ proc executeCgi(server: var TServer, client: Socket, path, query: string,
       dataAvail = recvLine(client, buf)
       if buf.len == 0:
         break
-      var L = toLower(buf)
+      var L = toLowerAscii(buf)
       if L.startsWith("content-length:"):
         var i = len("content-length:")
         while L[i] in Whitespace: inc(i)
@@ -205,7 +205,7 @@ proc acceptRequest(server: var TServer, client: Socket) =
     client.close()
   else:
     when defined(Windows):
-      var ext = splitFile(path).ext.toLower
+      var ext = splitFile(path).ext.toLowerAscii
       if ext == ".exe" or ext == ".cgi":
         # XXX: extract interpreter information here?
         cgi = true

lib/impure/nre.nim

@@ -10,7 +10,7 @@
 from pcre import nil
 import nre.private.util
 import tables
-from strutils import toLower, `%`
+from strutils import `%`
 from math import ceil
 import options
 from unicode import runeLenAt
@@ -326,15 +326,15 @@ proc `$`*(pattern: RegexMatch): string =
 
 proc `==`*(a, b: Regex): bool =
   if not a.isNil and not b.isNil:
-    return a.pattern   == b.pattern and
-           a.pcreObj   == b.pcreObj and
+    return a.pattern == b.pattern and
+           a.pcreObj == b.pcreObj and
            a.pcreExtra == b.pcreExtra
   else:
     return system.`==`(a, b)
 
 proc `==`*(a, b: RegexMatch): bool =
   return a.pattern == b.pattern and
-         a.str     == b.str
+         a.str == b.str
 # }}}
 
 # Creation & Destruction {{{

lib/pure/asyncnet.nim

@@ -201,7 +201,7 @@ when defineSsl:
       flags: set[SocketFlag]) {.async.} =
     let len = bioCtrlPending(socket.bioOut)
     if len > 0:
-      var data = newStringOfCap(len)
+      var data = newString(len)
       let read = bioRead(socket.bioOut, addr data[0], len)
       assert read != 0
       if read < 0:

lib/pure/base64.nim

@@ -52,7 +52,7 @@ template encodeInternal(s: typed, lineLen: int, newLine: string): untyped =
   if numLines > 0: inc(total, (numLines - 1) * newLine.len)
 
   result = newString(total)
-  var 
+  var
     i = 0
     r = 0
     currLine = 0
@@ -76,7 +76,7 @@ template encodeInternal(s: typed, lineLen: int, newLine: string): untyped =
       currLine = 0
 
   if i < s.len-1:
-    let 
+    let
       a = ord(s[i])
       b = ord(s[i+1])
     result[r] = cb64[a shr 2]
@@ -130,11 +130,11 @@ proc decode*(s: string): string =
   # total is an upper bound, as we will skip arbitrary whitespace:
   result = newString(total)
 
-  var 
+  var
     i = 0
     r = 0
   while true:
-    while s[i] in Whitespace: inc(i)
+    while i < s.len and s[i] in Whitespace: inc(i)
     if i < s.len-3:
       let
         a = s[i].decodeByte

lib/pure/collections/critbits.nim

@@ -74,18 +74,19 @@ proc rawInsert[T](c: var CritBitTree[T], key: string): Node[T] =
     var newByte = 0
     block blockX:
       while newbyte < key.len:
-        if it.key[newbyte] != key[newbyte]:
-          newotherbits = it.key[newbyte].ord xor key[newbyte].ord
+        let ch = if newbyte < it.key.len: it.key[newbyte] else: '\0'
+        if ch != key[newbyte]:
+          newotherbits = ch.ord xor key[newbyte].ord
           break blockX
         inc newbyte
-      if it.key[newbyte] != '\0':
+      if newbyte < it.key.len:
         newotherbits = it.key[newbyte].ord
       else:
         return it
     while (newOtherBits and (newOtherBits-1)) != 0:
       newOtherBits = newOtherBits and (newOtherBits-1)
     newOtherBits = newOtherBits xor 255
-    let ch = it.key[newByte]
+    let ch = if newByte < it.key.len: it.key[newByte] else: '\0'
     let dir = (1 + (ord(ch) or newOtherBits)) shr 8
 
     var inner: Node[T]

lib/pure/cookies.nim

@@ -25,16 +25,16 @@ proc parseCookies*(s: string): StringTableRef =
   result = newStringTable(modeCaseInsensitive)
   var i = 0
   while true:
-    while s[i] == ' ' or s[i] == '\t': inc(i)
+    while i < s.len and (s[i] == ' ' or s[i] == '\t'): inc(i)
     var keystart = i
-    while s[i] != '=' and s[i] != '\0': inc(i)
+    while i < s.len and s[i] != '=': inc(i)
     var keyend = i-1
-    if s[i] == '\0': break
+    if i >= s.len: break
     inc(i) # skip '='
     var valstart = i
-    while s[i] != ';' and s[i] != '\0': inc(i)
+    while i < s.len and s[i] != ';': inc(i)
     result[substr(s, keystart, keyend)] = substr(s, valstart, i-1)
-    if s[i] == '\0': break
+    if i >= s.len: break
     inc(i) # skip ';'
 
 proc setCookie*(key, value: string, domain = "", path = "",

lib/pure/encodings.nim

@@ -36,7 +36,7 @@ when defined(windows):
     while i < a.len and j < b.len:
       if a[i] in {'-', '_'}: inc i
       if b[j] in {'-', '_'}: inc j
-      if a[i].toLower != b[j].toLower: return false
+      if i < a.len and j < b.len and a[i].toLowerAscii != b[j].toLowerAscii: return false
       inc i
       inc j
     result = i == a.len and j == b.len

lib/pure/httpclient.nim

@@ -74,7 +74,7 @@
 ##
 ## .. code-block:: Nim
 ##    import asyncdispatch, httpclient
-##    
+##
 ##    proc onProgressChanged(total, progress, speed: BiggestInt) {.async.} =
 ##      echo("Downloaded ", progress, " of ", total)
 ##      echo("Current rate: ", speed div 1000, "kb/s")
@@ -247,7 +247,7 @@ proc parseChunks(s: Socket, timeout: int): string =
     var i = 0
     if chunkSizeStr == "":
       httpError("Server terminated connection prematurely")
-    while true:
+    while i < chunkSizeStr.len:
       case chunkSizeStr[i]
       of '0'..'9':
         chunkSize = chunkSize shl 4 or (ord(chunkSizeStr[i]) - ord('0'))
@@ -255,8 +255,6 @@ proc parseChunks(s: Socket, timeout: int): string =
         chunkSize = chunkSize shl 4 or (ord(chunkSizeStr[i]) - ord('a') + 10)
       of 'A'..'F':
         chunkSize = chunkSize shl 4 or (ord(chunkSizeStr[i]) - ord('A') + 10)
-      of '\0':
-        break
       of ';':
         # http://tools.ietf.org/html/rfc2616#section-3.6.1
         # We don't care about chunk-extensions.
@@ -938,7 +936,7 @@ proc parseChunks(client: HttpClient | AsyncHttpClient): Future[void]
     var i = 0
     if chunkSizeStr == "":
       httpError("Server terminated connection prematurely")
-    while true:
+    while i < chunkSizeStr.len:
       case chunkSizeStr[i]
       of '0'..'9':
         chunkSize = chunkSize shl 4 or (ord(chunkSizeStr[i]) - ord('0'))
@@ -946,8 +944,6 @@ proc parseChunks(client: HttpClient | AsyncHttpClient): Future[void]
         chunkSize = chunkSize shl 4 or (ord(chunkSizeStr[i]) - ord('a') + 10)
       of 'A'..'F':
         chunkSize = chunkSize shl 4 or (ord(chunkSizeStr[i]) - ord('A') + 10)
-      of '\0':
-        break
       of ';':
         # http://tools.ietf.org/html/rfc2616#section-3.6.1
         # We don't care about chunk-extensions.

lib/pure/httpcore.nim

@@ -190,11 +190,11 @@ proc len*(headers: HttpHeaders): int = return headers.table.len
 proc parseList(line: string, list: var seq[string], start: int): int =
   var i = 0
   var current = ""
-  while line[start + i] notin {'\c', '\l', '\0'}:
+  while start+i < line.len and line[start + i] notin {'\c', '\l'}:
     i += line.skipWhitespace(start + i)
     i += line.parseUntil(current, {'\c', '\l', ','}, start + i)
     list.add(current)
-    if line[start + i] == ',':
+    if start+i < line.len and line[start + i] == ',':
       i.inc # Skip ,
     current.setLen(0)
 

lib/pure/httpserver.nim

@@ -126,7 +126,7 @@ when false:
       var dataAvail = false
       while dataAvail:
         dataAvail = recvLine(client, buf) # TODO: This is incorrect.
-        var L = toLower(buf.string)
+        var L = toLowerAscii(buf.string)
         if L.startsWith("content-length:"):
           var i = len("content-length:")
           while L[i] in Whitespace: inc(i)
@@ -199,7 +199,7 @@ when false:
       notFound(client)
     else:
       when defined(Windows):
-        var ext = splitFile(path).ext.toLower
+        var ext = splitFile(path).ext.toLowerAscii
         if ext == ".exe" or ext == ".cgi":
           # XXX: extract interpreter information here?
           cgi = true
@@ -303,7 +303,7 @@ proc next*(s: var Server) =
   if s.reqMethod == "POST":
     # Check for Expect header
     if s.headers.hasKey("Expect"):
-      if s.headers["Expect"].toLower == "100-continue":
+      if s.headers["Expect"].toLowerAscii == "100-continue":
         s.client.sendStatus("100 Continue")
       else:
         s.client.sendStatus("417 Expectation Failed")
@@ -427,7 +427,7 @@ proc nextAsync(s: PAsyncHTTPServer) =
   if s.reqMethod == "POST":
     # Check for Expect header
     if s.headers.hasKey("Expect"):
-      if s.headers["Expect"].toLower == "100-continue":
+      if s.headers["Expect"].toLowerAscii == "100-continue":
         s.client.sendStatus("100 Continue")
       else:
         s.client.sendStatus("417 Expectation Failed")

lib/pure/logging.nim

@@ -126,7 +126,7 @@ proc substituteLog*(frmt: string, level: Level, args: varargs[string, `$`]): str
       var v = ""
       let app = when defined(js): "" else: getAppFilename()
       while frmt[i] in IdentChars:
-        v.add(toLower(frmt[i]))
+        v.add(toLowerAscii(frmt[i]))
         inc(i)
       case v
       of "date": result.add(getDateStr())

lib/pure/matchers.nim

@@ -29,21 +29,21 @@ proc validEmailAddress*(s: string): bool {.noSideEffect,
     chars = Letters + Digits + {'!','#','$','%','&',
       '\'','*','+','/','=','?','^','_','`','{','}','|','~','-','.'}
   var i = 0
-  if s[i] notin chars or s[i] == '.': return false
-  while s[i] in chars:
-    if s[i] == '.' and s[i+1] == '.': return false
+  if i >= s.len or s[i] notin chars or s[i] == '.': return false
+  while i < s.len and s[i] in chars:
+    if i+1 < s.len and s[i] == '.' and s[i+1] == '.': return false
     inc(i)
-  if s[i] != '@': return false
+  if i >= s.len or s[i] != '@': return false
   var j = len(s)-1
-  if s[j] notin Letters: return false
+  if j >= 0 and s[j] notin Letters: return false
   while j >= i and s[j] in Letters: dec(j)
   inc(i) # skip '@'
-  while s[i] in {'0'..'9', 'a'..'z', '-', '.'}: inc(i)
-  if s[i] != '\0': return false
+  while i < s.len and s[i] in {'0'..'9', 'a'..'z', '-', '.'}: inc(i)
+  if i != s.len: return false
 
   var x = substr(s, j+1)
   if len(x) == 2 and x[0] in Letters and x[1] in Letters: return true
-  case toLower(x)
+  case toLowerAscii(x)
   of "com", "org", "net", "gov", "mil", "biz", "info", "mobi", "name",
      "aero", "jobs", "museum": return true
   else: return false

lib/pure/os.nim

@@ -1060,18 +1060,17 @@ proc parseCmdLine*(c: string): seq[string] {.
   while true:
     setLen(a, 0)
     # eat all delimiting whitespace
-    while c[i] == ' ' or c[i] == '\t' or c[i] == '\l' or c[i] == '\r' : inc(i)
+    while i < c.len and c[i] in {' ', '\t', '\l', '\r'}: inc(i)
+    if i >= c.len: break
     when defined(windows):
       # parse a single argument according to the above rules:
-      if c[i] == '\0': break
       var inQuote = false
-      while true:
+      while i < c.len:
         case c[i]
-        of '\0': break
         of '\\':
           var j = i
-          while c[j] == '\\': inc(j)
-          if c[j] == '"':
+          while j < c.len and c[j] == '\\': inc(j)
+          if j < c.len and c[j] == '"':
             for k in 1..(j-i) div 2: a.add('\\')
             if (j-i) mod 2 == 0:
               i = j
@@ -1084,7 +1083,7 @@ proc parseCmdLine*(c: string): seq[string] {.
         of '"':
           inc(i)
           if not inQuote: inQuote = true
-          elif c[i] == '"':
+          elif i < c.len and c[i] == '"':
             a.add(c[i])
             inc(i)
           else:
@@ -1102,13 +1101,12 @@ proc parseCmdLine*(c: string): seq[string] {.
       of '\'', '\"':
         var delim = c[i]
         inc(i) # skip ' or "
-        while c[i] != '\0' and c[i] != delim:
+        while i < c.len and c[i] != delim:
           add a, c[i]
           inc(i)
-        if c[i] != '\0': inc(i)
-      of '\0': break
+        if i < c.len: inc(i)
       else:
-        while c[i] > ' ':
+        while i < c.len and c[i] > ' ':
           add(a, c[i])
           inc(i)
     add(result, a)

lib/pure/ospaths.nim

@@ -196,7 +196,7 @@ proc joinPath*(head, tail: string): string {.
     else:
       result = head & tail
   else:
-    if tail[0] in {DirSep, AltSep}:
+    if tail.len > 0 and tail[0] in {DirSep, AltSep}:
       result = head & tail
     else:
       result = head & DirSep & tail
@@ -477,7 +477,7 @@ proc unixToNativePath*(path: string, drive=""): string {.
 
     var i = start
     while i < len(path): # ../../../ --> ::::
-      if path[i] == '.' and path[i+1] == '.' and path[i+2] == '/':
+      if i+2 < path.len and path[i] == '.' and path[i+1] == '.' and path[i+2] == '/':
         # parent directory
         when defined(macos):
           if result[high(result)] == ':':

lib/pure/pegs.nim

@@ -534,15 +534,15 @@ proc rawMatch*(s: string, p: Peg, start: int, c: var Captures): int {.
   case p.kind
   of pkEmpty: result = 0 # match of length 0
   of pkAny:
-    if s[start] != '\0': result = 1
+    if start < s.len: result = 1
     else: result = -1
   of pkAnyRune:
-    if s[start] != '\0':
+    if start < s.len:
       result = runeLenAt(s, start)
     else:
       result = -1
   of pkLetter:
-    if s[start] != '\0':
+    if start < s.len:
       var a: Rune
       result = start
       fastRuneAt(s, result, a)
@@ -551,7 +551,7 @@ proc rawMatch*(s: string, p: Peg, start: int, c: var Captures): int {.
     else:
       result = -1
   of pkLower:
-    if s[start] != '\0':
+    if start < s.len:
       var a: Rune
       result = start
       fastRuneAt(s, result, a)
@@ -560,7 +560,7 @@ proc rawMatch*(s: string, p: Peg, start: int, c: var Captures): int {.
     else:
       result = -1
   of pkUpper:
-    if s[start] != '\0':
+    if start < s.len:
       var a: Rune
       result = start
       fastRuneAt(s, result, a)
@@ -569,7 +569,7 @@ proc rawMatch*(s: string, p: Peg, start: int, c: var Captures): int {.
     else:
       result = -1
   of pkTitle:
-    if s[start] != '\0':
+    if start < s.len:
       var a: Rune
       result = start
       fastRuneAt(s, result, a)
@@ -578,7 +578,7 @@ proc rawMatch*(s: string, p: Peg, start: int, c: var Captures): int {.
     else:
       result = -1
   of pkWhitespace:
-    if s[start] != '\0':
+    if start < s.len:
       var a: Rune
       result = start
       fastRuneAt(s, result, a)
@@ -589,15 +589,15 @@ proc rawMatch*(s: string, p: Peg, start: int, c: var Captures): int {.
   of pkGreedyAny:
     result = len(s) - start
   of pkNewLine:
-    if s[start] == '\L': result = 1
-    elif s[start] == '\C':
-      if s[start+1] == '\L': result = 2
+    if start < s.len and s[start] == '\L': result = 1
+    elif start < s.len and s[start] == '\C':
+      if start+1 < s.len and s[start+1] == '\L': result = 2
       else: result = 1
     else: result = -1
   of pkTerminal:
     result = len(p.term)
     for i in 0..result-1:
-      if p.term[i] != s[start+i]:
+      if start+i >= s.len or p.term[i] != s[start+i]:
         result = -1
         break
   of pkTerminalIgnoreCase:
@@ -606,6 +606,9 @@ proc rawMatch*(s: string, p: Peg, start: int, c: var Captures): int {.
       a, b: Rune
     result = start
     while i < len(p.term):
+      if result >= s.len:
+        result = -1
+        break
       fastRuneAt(p.term, i, a)
       fastRuneAt(s, result, b)
       if toLower(a) != toLower(b):
@@ -621,18 +624,23 @@ proc rawMatch*(s: string, p: Peg, start: int, c: var Captures): int {.
       while true:
         fastRuneAt(p.term, i, a)
         if a != Rune('_'): break
-      while true:
+      while result < s.len:
         fastRuneAt(s, result, b)
         if b != Rune('_'): break
-      if toLower(a) != toLower(b):
+      if result >= s.len:
+        if i >= p.term.len: break
+        else:
+          result = -1
+          break
+      elif toLower(a) != toLower(b):
         result = -1
         break
     dec(result, start)
   of pkChar:
-    if p.ch == s[start]: result = 1
+    if start < s.len and p.ch == s[start]: result = 1
     else: result = -1
   of pkCharChoice:
-    if contains(p.charChoice[], s[start]): result = 1
+    if start < s.len and contains(p.charChoice[], s[start]): result = 1
     else: result = -1
   of pkNonTerminal:
     var oldMl = c.ml
@@ -695,10 +703,10 @@ proc rawMatch*(s: string, p: Peg, start: int, c: var Captures): int {.
   of pkGreedyRepChar:
     result = 0
     var ch = p.ch
-    while ch == s[start+result]: inc(result)
+    while start+result < s.len and ch == s[start+result]: inc(result)
   of pkGreedyRepSet:
     result = 0
-    while contains(p.charChoice[], s[start+result]): inc(result)
+    while start+result < s.len and contains(p.charChoice[], s[start+result]): inc(result)
   of pkOption:
     result = max(0, rawMatch(s, p.sons[0], start, c))
   of pkAndPredicate:

lib/pure/strutils.nim

@@ -1126,7 +1126,7 @@ proc unindent*(s: string, count: Natural, padding: string = " "): string
     var indentCount = 0
     for j in 0..<count.int:
       indentCount.inc
-      if line[j .. j + padding.len-1] != padding:
+      if j + padding.len-1 >= line.len or line[j .. j + padding.len-1] != padding:
         indentCount = j
         break
     result.add(line[indentCount*padding.len .. ^1])

lib/pure/times.nim

@@ -1318,24 +1318,23 @@ proc format*(dt: DateTime, f: string): string {.tags: [].}=
   result = ""
   var i = 0
   var currentF = ""
-  while true:
+  while i < f.len:
     case f[i]
-    of ' ', '-', '/', ':', '\'', '\0', '(', ')', '[', ']', ',':
+    of ' ', '-', '/', ':', '\'', '(', ')', '[', ']', ',':
       formatToken(dt, currentF, result)
 
       currentF = ""
-      if f[i] == '\0': break
 
       if f[i] == '\'':
         inc(i) # Skip '
-        while f[i] != '\'' and f.len-1 > i:
+        while i < f.len-1 and f[i] != '\'':
           result.add(f[i])
           inc(i)
       else: result.add(f[i])
 
     else:
       # Check if the letter being added matches previous accumulated buffer.
-      if currentF.len < 1 or currentF[high(currentF)] == f[i]:
+      if currentF.len == 0 or currentF[high(currentF)] == f[i]:
         currentF.add(f[i])
       else:
         formatToken(dt, currentF, result)
@@ -1343,6 +1342,7 @@ proc format*(dt: DateTime, f: string): string {.tags: [].}=
         currentF = ""
 
     inc(i)
+  formatToken(dt, currentF, result)
 
 proc `$`*(dt: DateTime): string {.tags: [], raises: [], benign.} =
   ## Converts a `DateTime` object to a string representation.
@@ -1439,58 +1439,58 @@ proc parseToken(dt: var DateTime; token, value: string; j: var int) =
     dt.month = month.Month
   of "MMM":
     case value[j..j+2].toLowerAscii():
-    of "jan": dt.month =  mJan
-    of "feb": dt.month =  mFeb
-    of "mar": dt.month =  mMar
-    of "apr": dt.month =  mApr
-    of "may": dt.month =  mMay
-    of "jun": dt.month =  mJun
-    of "jul": dt.month =  mJul
-    of "aug": dt.month =  mAug
-    of "sep": dt.month =  mSep
-    of "oct": dt.month =  mOct
-    of "nov": dt.month =  mNov
-    of "dec": dt.month =  mDec
+    of "jan": dt.month = mJan
+    of "feb": dt.month = mFeb
+    of "mar": dt.month = mMar
+    of "apr": dt.month = mApr
+    of "may": dt.month = mMay
+    of "jun": dt.month = mJun
+    of "jul": dt.month = mJul
+    of "aug": dt.month = mAug
+    of "sep": dt.month = mSep
+    of "oct": dt.month = mOct
+    of "nov": dt.month = mNov
+    of "dec": dt.month = mDec
     else:
       raise newException(ValueError,
         "Couldn't parse month (MMM), got: " & value)
     j += 3
   of "MMMM":
     if value.len >= j+7 and value[j..j+6].cmpIgnoreCase("january") == 0:
-      dt.month =  mJan
+      dt.month = mJan
       j += 7
     elif value.len >= j+8 and value[j..j+7].cmpIgnoreCase("february") == 0:
-      dt.month =  mFeb
+      dt.month = mFeb
       j += 8
     elif value.len >= j+5 and value[j..j+4].cmpIgnoreCase("march") == 0:
-      dt.month =  mMar
+      dt.month = mMar
       j += 5
     elif value.len >= j+5 and value[j..j+4].cmpIgnoreCase("april") == 0:
-      dt.month =  mApr
+      dt.month = mApr
       j += 5
     elif value.len >= j+3 and value[j..j+2].cmpIgnoreCase("may") == 0:
-      dt.month =  mMay
+      dt.month = mMay
       j += 3
     elif value.len >= j+4 and value[j..j+3].cmpIgnoreCase("june") == 0:
-      dt.month =  mJun
+      dt.month = mJun
       j += 4
     elif value.len >= j+4 and value[j..j+3].cmpIgnoreCase("july") == 0:
-      dt.month =  mJul
+      dt.month = mJul
       j += 4
     elif value.len >= j+6 and value[j..j+5].cmpIgnoreCase("august") == 0:
-      dt.month =  mAug
+      dt.month = mAug
       j += 6
     elif value.len >= j+9 and value[j..j+8].cmpIgnoreCase("september") == 0:
-      dt.month =  mSep
+      dt.month = mSep
       j += 9
     elif value.len >= j+7 and value[j..j+6].cmpIgnoreCase("october") == 0:
-      dt.month =  mOct
+      dt.month = mOct
       j += 7
     elif value.len >= j+8 and value[j..j+7].cmpIgnoreCase("november") == 0:
-      dt.month =  mNov
+      dt.month = mNov
       j += 8
     elif value.len >= j+8 and value[j..j+7].cmpIgnoreCase("december") == 0:
-      dt.month =  mDec
+      dt.month = mDec
       j += 8
     else:
       raise newException(ValueError,
@@ -1521,44 +1521,47 @@ proc parseToken(dt: var DateTime; token, value: string; j: var int) =
     j += 4
   of "z":
     dt.isDst = false
-    if value[j] == '+':
+    let ch = if j < value.len: value[j] else: '\0'
+    if ch == '+':
       dt.utcOffset = 0 - parseInt($value[j+1]) * secondsInHour
-    elif value[j] == '-':
+    elif ch == '-':
       dt.utcOffset = parseInt($value[j+1]) * secondsInHour
-    elif value[j] == 'Z':
+    elif ch == 'Z':
       dt.utcOffset = 0
       j += 1
       return
     else:
       raise newException(ValueError,
-        "Couldn't parse timezone offset (z), got: " & value[j])
+        "Couldn't parse timezone offset (z), got: " & ch)
     j += 2
   of "zz":
     dt.isDst = false
-    if value[j] == '+':
+    let ch = if j < value.len: value[j] else: '\0'
+    if ch == '+':
       dt.utcOffset = 0 - value[j+1..j+2].parseInt() * secondsInHour
-    elif value[j] == '-':
+    elif ch == '-':
       dt.utcOffset = value[j+1..j+2].parseInt() * secondsInHour
-    elif value[j] == 'Z':
+    elif ch == 'Z':
       dt.utcOffset = 0
       j += 1
       return
     else:
       raise newException(ValueError,
-        "Couldn't parse timezone offset (zz), got: " & value[j])
+        "Couldn't parse timezone offset (zz), got: " & ch)
     j += 3
   of "zzz":
     dt.isDst = false
     var factor = 0
-    if value[j] == '+': factor = -1
-    elif value[j] == '-': factor = 1
-    elif value[j] == 'Z':
+    let ch = if j < value.len: value[j] else: '\0'
+    if ch == '+': factor = -1
+    elif ch == '-': factor = 1
+    elif ch == 'Z':
       dt.utcOffset = 0
       j += 1
       return
     else:
       raise newException(ValueError,
-        "Couldn't parse timezone offset (zzz), got: " & value[j])
+        "Couldn't parse timezone offset (zzz), got: " & ch)
     dt.utcOffset = factor * value[j+1..j+2].parseInt() * secondsInHour
     j += 4
     dt.utcOffset += factor * value[j..j+1].parseInt() * 60
@@ -1620,20 +1623,18 @@ proc parse*(value, layout: string, zone: Timezone = local()): DateTime =
   dt.nanosecond = 0
   dt.isDst = true # using this is flag for checking whether a timezone has \
       # been read (because DST is always false when a tz is parsed)
-  while true:
+  while i < layout.len:
     case layout[i]
-    of ' ', '-', '/', ':', '\'', '\0', '(', ')', '[', ']', ',':
+    of ' ', '-', '/', ':', '\'', '(', ')', '[', ']', ',':
       if token.len > 0:
         parseToken(dt, token, value, j)
       # Reset token
       token = ""
-      # Break if at end of line
-      if layout[i] == '\0': break
       # Skip separator and everything between single quotes
       # These are literals in both the layout and the value string
       if layout[i] == '\'':
         inc(i)
-        while layout[i] != '\'' and layout.len-1 > i:
+        while i < layout.len-1 and layout[i] != '\'':
           inc(i)
           inc(j)
         inc(i)
@@ -1642,13 +1643,15 @@ proc parse*(value, layout: string, zone: Timezone = local()): DateTime =
         inc(j)
     else:
       # Check if the letter being added matches previous accumulated buffer.
-      if token.len < 1 or token[high(token)] == layout[i]:
+      if token.len == 0 or token[high(token)] == layout[i]:
         token.add(layout[i])
         inc(i)
       else:
         parseToken(dt, token, value, j)
         token = ""
 
+  if i >= layout.len and token.len > 0:
+    parseToken(dt, token, value, j)
   if dt.isDst:
     # No timezone parsed - assume timezone is `zone`
     result = initDateTime(zone.zoneInfoFromTz(dt.toAdjTime), zone)

lib/pure/xmldom.nim

@@ -232,10 +232,10 @@ proc createAttributeNS*(doc: PDocument, namespaceURI: string, qualifiedName: str
     raise newException(EInvalidCharacterErr, "Invalid character")
   # Exceptions
   if qualifiedName.contains(':'):
-    let qfnamespaces = qualifiedName.toLower().split(':')
+    let qfnamespaces = qualifiedName.toLowerAscii().split(':')
     if isNil(namespaceURI):
       raise newException(ENamespaceErr, "When qualifiedName contains a prefix namespaceURI cannot be nil")
-    elif qfnamespaces[0] == "xml" and 
+    elif qfnamespaces[0] == "xml" and
         namespaceURI != "http://www.w3.org/XML/1998/namespace" and
         qfnamespaces[1] notin stdattrnames:
       raise newException(ENamespaceErr,
@@ -311,10 +311,10 @@ proc createElement*(doc: PDocument, tagName: string): PElement =
 proc createElementNS*(doc: PDocument, namespaceURI: string, qualifiedName: string): PElement =
   ## Creates an element of the given qualified name and namespace URI.
   if qualifiedName.contains(':'):
-    let qfnamespaces = qualifiedName.toLower().split(':')
+    let qfnamespaces = qualifiedName.toLowerAscii().split(':')
     if isNil(namespaceURI):
       raise newException(ENamespaceErr, "When qualifiedName contains a prefix namespaceURI cannot be nil")
-    elif qfnamespaces[0] == "xml" and 
+    elif qfnamespaces[0] == "xml" and
         namespaceURI != "http://www.w3.org/XML/1998/namespace" and
         qfnamespaces[1] notin stdattrnames:
       raise newException(ENamespaceErr,
@@ -533,13 +533,13 @@ proc `prefix=`*(n: PNode, value: string) =
 
   if isNil(n.fNamespaceURI):
     raise newException(ENamespaceErr, "namespaceURI cannot be nil")
-  elif value.toLower() == "xml" and n.fNamespaceURI != "http://www.w3.org/XML/1998/namespace":
+  elif value.toLowerAscii() == "xml" and n.fNamespaceURI != "http://www.w3.org/XML/1998/namespace":
     raise newException(ENamespaceErr,
       "When the namespace prefix is \"xml\" namespaceURI has to be \"http://www.w3.org/XML/1998/namespace\"")
-  elif value.toLower() == "xmlns" and n.fNamespaceURI != "http://www.w3.org/2000/xmlns/":
+  elif value.toLowerAscii() == "xmlns" and n.fNamespaceURI != "http://www.w3.org/2000/xmlns/":
     raise newException(ENamespaceErr,
       "When the namespace prefix is \"xmlns\" namespaceURI has to be \"http://www.w3.org/2000/xmlns/\"")
-  elif value.toLower() == "xmlns" and n.fNodeType == AttributeNode:
+  elif value.toLowerAscii() == "xmlns" and n.fNodeType == AttributeNode:
     raise newException(ENamespaceErr, "An AttributeNode cannot have a prefix of \"xmlns\"")
 
   n.fNodeName = value & ":" & n.fLocalName

tests/async/tlambda.nim

@@ -1,7 +1,7 @@
 
 # bug 2007
 
-import asyncdispatch, asyncnet, logging, json, uri, strutils, future
+import asyncdispatch, asyncnet, logging, json, uri, strutils, sugar
 
 type
   Builder = ref object
@@ -27,7 +27,7 @@ proc newBuild*(onProgress: ProgressCB): Build =
   result.onProgress = onProgress
 
 proc start(build: Build, repo, hash: string) {.async.} =
-  let path = repo.parseUri().path.toLower()
+  let path = repo.parseUri().path.toLowerAscii()
 
 proc onProgress(builder: Builder, message: string) {.async.} =
   debug($message)

tests/concepts/tstackconcept.nim

@@ -31,7 +31,7 @@ type
     s.pop() is T
 
     type ValueType = T
-    const ValueTypeName = T.name.toUpper
+    const ValueTypeName = T.name.toUpperAscii
 
 proc genericAlgorithm[T](s: var Stack[T], y: T) =
   static:

tests/manyloc/keineschweine/dependencies/nake/nakefile.nim

@@ -7,7 +7,7 @@ task "install", "compile and install nake binary":
     for index, dir in pairs(path):
       echo "  ", index, ". ", dir
     echo "Where to install nake binary? (quit with ^C or quit or exit)"
-    let ans = stdin.readLine().toLower
+    let ans = stdin.readLine().toLowerAscii
     var index = 0
     case ans
     of "q", "quit", "x", "exit":

tests/manyloc/keineschweine/lib/sg_assets.nim

@@ -562,7 +562,7 @@ proc importItem(data: PJsonNode; errors: var seq[string]): PItemRecord =
 
   result.useSound = importSound(data[2], errors, "useSound")
 
-  case data[1].str.toLower
+  case data[1].str.toLowerAscii
   of "projectile":
     result.kind = Projectile
     if data[2]["bullet"].kind == JString:

tests/manyloc/nake/nakefile.nim

@@ -88,7 +88,7 @@ task "download", "download game assets":
   if existsFile(path):
     echo "The file already exists\n",
       "[R]emove  [M]ove  [Q]uit  [S]kip    Source: ", GameAssets
-    case stdin.readLine.toLower
+    case stdin.readLine.toLowerAscii
     of "r":
       removeFile path
     of "m":
@@ -120,7 +120,7 @@ task "download", "download game assets":
 
   echo "Download binary libs? Only libs for linux are available currently, enjoy the irony.\n",
     "[Y]es [N]o   Source: ", BinLibs
-  case stdin.readline.toLower
+  case stdin.readline.toLowerAscii
   of "y", "yes":
     discard ## o_O
   else:

tests/method/tsimmeth.nim

@@ -6,7 +6,7 @@ discard """
 
 import strutils
 
-var x = "hello world!".toLower.toUpper
+var x = "hello world!".toLowerAscii.toUpperAscii
 x.echo()
 #OUT HELLO WORLD!
 

tests/misc/tmemoization.nim

@@ -8,7 +8,7 @@ import strutils
 proc foo(s: static[string]): string =
   static: echo s
 
-  const R = s.toUpper
+  const R = s.toUpperAscii
   return R
 
 echo foo("test 1")

tests/stdlib/twchartoutf8.nim

@@ -30,7 +30,6 @@ else:
     result = newString(size)
     let res = WideCharToMultiByte(CP_UTF8, 0'i32, cast[LPWCSTR](addr(wc[0])), wclen,
       cstring(result), size, cstring(nil), LPBOOL(nil))
-    result[size] = chr(0)
     doAssert size == res
 
   proc testCP(wc: WideCString, lo, hi: int) =