implements experimental new config system based on NimScript

lib/system/nimscript.nim

@@ -0,0 +1,152 @@
+#
+#
+#            Nim's Runtime Library
+#        (c) Copyright 2015 Andreas Rumpf
+#
+#    See the file "copying.txt", included in this
+#    distribution, for details about the copyright.
+#
+
+
+# Nim's configuration system now uses Nim for scripting. This module provides
+# a few things that are required for this to work.
+
+template builtin = discard
+
+proc listDirs*(dir: string): seq[string] = builtin
+proc listFiles*(dir: string): seq[string] = builtin
+
+proc removeDir(dir: string) = builtin
+proc removeFile(dir: string) = builtin
+proc moveFile(src, dest: string) = builtin
+proc createDir(dir: string) = builtin
+proc getOsError: string = builtin
+proc setCurrentDir(dir: string) = builtin
+proc getCurrentDir(): string = builtin
+proc paramStr*(i: int): string = builtin
+proc paramCount*(): int = builtin
+
+proc switch*(key: string, val="") = builtin
+proc getCommand*(): string = builtin
+proc setCommand*(cmd: string) = builtin
+proc cmpIgnoreStyle(a, b: string): int = builtin
+
+proc strip(s: string): string =
+  var i = 0
+  while s[i] in {' ', '\c', '\L'}: inc i
+  result = s.substr(i)
+
+template `--`*(key, val: untyped) = switch(astToStr(key), strip astToStr(val))
+template `--`*(key: untyped) = switch(astToStr(key), "")
+
+type
+  ScriptMode* {.pure.} = enum
+    Silent,
+    Verbose,
+    Whatif
+
+var
+  mode*: ScriptMode ## Set this to influence how mkDir, rmDir, rmFile etc.
+                    ## behave
+
+template checkOsError =
+  let err = getOsError()
+  if err.len > 0: raise newException(OSError, err)
+
+template log(msg: string, body: untyped) =
+  if mode == ScriptMode.Verbose or mode == ScriptMode.Whatif:
+    echo "[NimScript] ", msg
+  if mode != ScriptMode.WhatIf:
+    body
+
+proc rmDir*(dir: string) {.raises: [OSError].} =
+  log "rmDir: " & dir:
+    removeDir dir
+    checkOsError()
+
+proc rmFile*(dir: string) {.raises: [OSError].} =
+  log "rmFile: " & dir:
+    removeFile dir
+    checkOsError()
+
+proc mkDir*(dir: string) {.raises: [OSError].} =
+  log "mkDir: " & dir:
+    createDir dir
+    checkOsError()
+
+proc mvFile*(`from`, to: string) {.raises: [OSError].} =
+  log "mvFile: " & `from` & ", " & to:
+    moveFile `from`, to
+    checkOsError()
+
+proc exec*(command: string, input = "", cache = "") =
+  ## Executes an external process.
+  log "exec: " & command:
+    echo staticExec(command, input, cache)
+
+proc put*(key, value: string) =
+  ## Sets a configuration 'key' like 'gcc.options.always' to its value.
+  builtin
+
+proc get*(key: string): string =
+  ## Retrieves a configuration 'key' like 'gcc.options.always'.
+  builtin
+
+proc exists*(key: string): bool =
+  ## Checks for the existance of a configuration 'key'
+  ## like 'gcc.options.always'.
+  builtin
+
+proc nimcacheDir*(): string =
+  ## Retrieves the location of 'nimcache'.
+  builtin
+
+proc thisDir*(): string =
+  ## Retrieves the location of the current ``nims`` script file.
+  builtin
+
+proc cd*(dir: string) {.raises: [OSError].} =
+  ## Changes the current directory.
+  ##
+  ## The change is permanent for the rest of the execution, since this is just
+  ## a shortcut for `os.setCurrentDir()
+  ## <http://nim-lang.org/os.html#setCurrentDir,string>`_ . Use the `withDir()
+  ## <#withDir>`_ template if you want to perform a temporary change only.
+  setCurrentDir(dir)
+  checkOsError()
+
+template withDir*(dir: string; body: untyped): untyped =
+  ## Changes the current directory temporarily.
+  ##
+  ## If you need a permanent change, use the `cd() <#cd>`_ proc. Usage example:
+  ##
+  ## .. code-block:: nimrod
+  ##   withDir "foo":
+  ##     # inside foo
+  ##   #back to last dir
+  var curDir = getCurrentDir()
+  try:
+    cd(dir)
+    body
+  finally:
+    cd(curDir)
+
+template `==?`(a, b: string): bool = cmpIgnoreStyle(a, b) == 0
+
+proc writeTask(name, desc: string) =
+  if desc.len > 0:
+    var spaces = " "
+    for i in 0 ..< 20 - name.len: spaces.add ' '
+    echo name, spaces, desc
+
+template task*(name: untyped; description: string; body: untyped): untyped =
+  ## Defines a task. Hidden tasks are supported via an empty description.
+  proc `name Task`() = body
+
+  let cmd = getCommand()
+  if cmd.len == 0 or cmd ==? "help" or cmd == "nop":
+    setCommand "nop"
+    writeTask(astToStr(name), description)
+  elif cmd ==? astToStr(name):
+    setCommand "nop"
+    `name Task`()

lib/system/sysio.nim

@@ -182,7 +182,10 @@ proc readAllFile(file: File): string =
 proc readAll(file: File): TaintedString =
   # Separate handling needed because we need to buffer when we
   # don't know the overall length of the File.
-  let len = if file != stdin: rawFileSize(file) else: -1
+  when declared(stdin):
+    let len = if file != stdin: rawFileSize(file) else: -1
+  else:
+    let len = rawFileSize(file)
   if len > 0:
     result = readAllFile(file, len).TaintedString
   else:
@@ -216,9 +219,9 @@ proc writeLine[Ty](f: File, x: varargs[Ty, `$`]) =
   for i in items(x): write(f, i)
   write(f, "\n")
 
-
-proc rawEcho(x: string) {.inline, compilerproc.} = write(stdout, x)
-proc rawEchoNL() {.inline, compilerproc.} = write(stdout, "\n")
+when declared(stdout):
+  proc rawEcho(x: string) {.inline, compilerproc.} = write(stdout, x)
+  proc rawEchoNL() {.inline, compilerproc.} = write(stdout, "\n")
 
 # interface to the C procs: