nimble install: add --noRebuild option (#966)

* Add --noRebuild option for install

* Add --noRebuild test in tmisctests.nim

src/nimble.nim

@@ -191,14 +191,21 @@ proc buildFromDir(pkgInfo: PackageInfo, paths: HashSet[string],
       if bin.extractFilename().changeFileExt("") != binToBuild:
         continue
 
+    let outputDir = pkgInfo.getOutputDir("")
+    if dirExists(outputDir):
+      if fileExists(outputDir / bin):
+        if not pkgInfo.needsRebuild(outputDir / bin, realDir, options):
+          display("Skipping", "$1/$2 (up-to-date)" %
+                  [pkginfo.basicInfo.name, bin], priority = HighPriority)
+          binariesBuilt.inc()
+          continue
+    else:
+      createDir(outputDir)
+
     let outputOpt = "-o:" & pkgInfo.getOutputDir(bin).quoteShell
     display("Building", "$1/$2 using $3 backend" %
             [pkginfo.basicInfo.name, bin, pkgInfo.backend], priority = HighPriority)
 
-    let outputDir = pkgInfo.getOutputDir("")
-    if not dirExists(outputDir):
-      createDir(outputDir)
-
     let input = realDir / src.changeFileExt("nim")
     # `quoteShell` would be more robust than `\"` (and avoid quoting when
     # un-necessary) but would require changing `extractBin`

src/nimblepkg/options.nim

@@ -68,6 +68,7 @@ type
       passNimFlags*: seq[string]
       devActions*: seq[DevelopAction]
       path*: string
+      noRebuild*: bool
       withDependencies*: bool
         ## Whether to put in develop mode also the dependencies of the packages
         ## listed in the develop command.
@@ -99,6 +100,7 @@ Commands:
   install      [pkgname, ...]     Installs a list of packages.
                [-d, --depsOnly]   Install only dependencies.
                [-p, --passNim]    Forward specified flag to compiler.
+               [--noRebuild]      Don't rebuild binaries if they're up-to-date.
   develop      [pkgname, ...]     Clones a list of packages for development.
                                   Adds them to a develop file if specified or
                                   to `nimble.develop` if not specified and
@@ -499,6 +501,8 @@ proc parseFlag*(flag, val: string, result: var Options, kind = cmdLongOption) =
     case f
     of "depsonly", "d":
       result.depsOnly = true
+    of "norebuild":
+      result.action.noRebuild = true
     of "passnim", "p":
       result.action.passNimFlags.add(val)
     else:

src/nimblepkg/packageinfo.nim

@@ -3,7 +3,7 @@
 
 # Stdlib imports
 import system except TResult
-import hashes, json, strutils, os, sets, tables, httpclient, strformat
+import hashes, json, strutils, os, sets, tables, times, httpclient, strformat
 from net import SslError
 
 # Local imports
@@ -494,6 +494,22 @@ proc iterInstallFiles*(realDir: string, pkgInfo: PackageInfo,
 
         action(file)
 
+proc needsRebuild*(pkgInfo: PackageInfo, bin: string, dir: string, options: Options): bool =
+  if options.action.typ != actionInstall:
+    return true
+  if not options.action.noRebuild:
+    return true
+
+  let binTimestamp = getFileInfo(bin).lastWriteTime
+  var rebuild = false
+  iterFilesWithExt(dir, pkgInfo,
+    proc (file: string) =
+      let srcTimestamp = getFileInfo(file).lastWriteTime
+      if binTimestamp < srcTimestamp:
+        rebuild = true
+  )
+  return rebuild
+
 proc getCacheDir*(pkgInfo: PackageBasicInfo): string =
   &"{pkgInfo.name}-{pkgInfo.version}-{$pkgInfo.checksum}"
 
@@ -515,7 +531,7 @@ proc getNameAndVersion*(pkgInfo: PackageInfo): string =
   &"{pkgInfo.basicInfo.name}@{pkgInfo.basicInfo.version}"
 
 when isMainModule:
-  import unittest 
+  import unittest
 
   test "toValidPackageName":
     check toValidPackageName("foo__bar") == "foo_bar"

tests/tmisctests.nim

@@ -50,6 +50,14 @@ suite "misc tests":
       let (_, exitCode) = execNimble("install", "--passNim:-d:passNimIsWorking")
       check exitCode == QuitSuccess
 
+  test "install with --noRebuild flag":
+    cd "run":
+      check execNimbleYes("build").exitCode == QuitSuccess
+
+      let (output, exitCode) = execNimbleYes("install", "--noRebuild")
+      check exitCode == QuitSuccess
+      check output.contains("Skipping")
+
   test "NimbleVersion is defined":
     cd "nimbleVersionDefine":
       let (output, exitCode) = execNimble("c", "-r", "src/nimbleVersionDefine.nim")