nixpkgs/pkgs/by-name/ni/nim_builder/nim_builder.nim
2023-11-28 16:48:10 +02:00

180 lines
5.6 KiB
Nim

# SPDX-FileCopyrightText: 2021 Nixpkgs/NixOS contributors
## Custom Nim builder for Nixpkgs.
import std/[os, osproc, parseutils, sequtils, streams, strutils]
proc findNimbleFile(): string =
## Copied from Nimble.
## Copyright (c) 2015, Dominik Picheta
## BSD3
let dir = getCurrentDir()
result = ""
var hits = 0
for kind, path in walkDir(dir):
if kind in {pcFile, pcLinkToFile}:
let ext = path.splitFile.ext
if ext == ".nimble":
result = path
inc hits
if hits >= 2:
quit("Only one .nimble file should be present in " & dir)
elif hits == 0:
quit("Could not find a file with a .nimble extension in " & dir)
proc getEnvBool(key: string; default = false): bool =
## Parse a boolean environmental variable.
let val = getEnv(key)
if val == "": default
else: parseBool(val)
proc getNimbleFilePath(): string =
## Get the Nimble file for the current package.
if existsEnv"nimbleFile":
getEnv"nimbleFile"
else:
findNimbleFile()
proc getNimbleValue(filePath, key: string; default = ""): string =
## Extract a string value from the Nimble file at ``filePath``.
var
fs = newFileStream(filePath, fmRead)
line: string
if fs.isNil:
quit("could not open " & filePath)
while fs.readline(line):
if line.startsWith(key):
var i = key.len
i.inc skipWhile(line, Whitespace, i)
if line[i] == '=':
inc i
i.inc skipWhile(line, Whitespace, i)
discard parseUntil(line, result, Newlines, i)
if result.len > 0 and result[0] == '"':
result = result.unescape
return
default
proc getNimbleValues(filePath, key: string): seq[string] =
## Extract a string sequence from the Nimble file at ``filePath``.
var gunk = getNimbleValue(filePath, key)
result = gunk.strip(chars = {'@', '[', ']'}).split(',')
if result == @[""]: reset result
apply(result) do (s: var string):
s = s.strip()
if s.len > 0 and s[0] == '"':
s = s.unescape()
proc getOutputDir(name: string): string =
## Return the output directory for output `name`.
## If `name` is not a valid output then the first output
## is returned as a default.
let outputs = splitWhitespace getEnv("outputs")
doAssert(outputs.len > 0)
if outputs.contains name:
result = getEnv(name)
if result == "":
result = getEnv("out")
if result == "":
result = getEnv(outputs[0], "/dev/null")
proc configurePhase*() =
## Generate "config.nims" which will be read by the Nim
## compiler during later phases.
const configFilePath = "config.nims"
echo "generating ", configFilePath
let
nf = getNimbleFilePath()
mode =
if fileExists configFilePath: fmAppend
else: fmWrite
var cfg = newFileStream(configFilePath, mode)
proc switch(key, val: string) =
cfg.writeLine("switch(", key.escape, ",", val.escape, ")")
switch("backend", nf.getNimbleValue("backend", "c"))
switch("nimcache", getEnv("NIX_BUILD_TOP", ".") / "nimcache")
if getEnvBool("nimRelease", true):
switch("define", "release")
for def in getEnv("nimDefines").split:
if def != "":
switch("define", def)
for input in getEnv("NIX_NIM_BUILD_INPUTS").split:
if input != "":
for nimbleFile in walkFiles(input / "*.nimble"):
let inputSrc = normalizedPath(
input / nimbleFile.getNimbleValue("srcDir", "."))
echo "found nimble input ", inputSrc
switch("path", inputSrc)
close(cfg)
proc buildPhase*() =
## Build the programs listed in the Nimble file and
## optionally some documentation.
var cmds: seq[string]
proc before(idx: int) =
echo "build job ", idx, ": ", cmds[idx]
let
nf = getNimbleFilePath()
bins = nf.getNimbleValues("bin")
srcDir = nf.getNimbleValue("srcDir", ".")
binDir = getOutputDir("bin") / "bin"
if bins != @[]:
for bin in bins:
cmds.add("nim compile $# --parallelBuild:$# --outdir:$# $#" %
[getenv("nimFlags"), getenv("NIX_BUILD_CORES","1"), binDir, normalizedPath(srcDir / bin)])
if getEnvBool"nimDoc":
echo "generating documentation"
let docDir = getOutputDir("doc") / "doc"
for path in walkFiles(srcDir / "*.nim"):
cmds.add("nim doc --outdir:$# $#" % [docDir, path])
if cmds.len > 0:
let err = execProcesses(
cmds, n = 1,
beforeRunEvent = before)
if err != 0: quit("build phase failed", err)
proc installPhase*() =
## Install the Nim sources if ``nimCopySources`` is
## set in the environment.
if getEnvBool"nimCopySources":
let
nf = getNimbleFilePath()
srcDir = nf.getNimbleValue("srcDir", ".")
devDir = getOutputDir "dev"
echo "Install ", srcDir, " to ", devDir
copyDir(normalizedPath(srcDir), normalizedPath(devDir / srcDir))
copyFile(nf, devDir / nf.extractFilename)
proc checkPhase*() =
## Build and run the tests in ``tests``.
var cmds: seq[string]
proc before(idx: int) =
echo "check job ", idx, ": ", cmds[idx]
for path in walkPattern("tests/t*.nim"):
cmds.add("nim r $# $#" % [getenv("nimFlags"), path])
let err = execProcesses(
cmds, n = 1,
beforeRunEvent = before)
if err != 0: quit("check phase failed", err)
when isMainModule:
import std/parseopt
var phase: string
for kind, key, val in getopt():
case kind
of cmdLongOption:
case key.toLowerAscii
of "phase":
if phase != "": quit("only a single phase may be specified")
phase = val
else: quit("unhandled argument " & key)
of cmdEnd: discard
else: quit("unhandled argument " & key)
case phase
of "configure": configurePhase()
of "build": buildPhase()
of "install": installPhase()
of "check": checkPhase()
else: quit("unhandled phase " & phase)