make koch and tools work with nimPreviewSlimSystem (#20459)

koch.nim

@@ -34,6 +34,9 @@ import std/[os, strutils, parseopt, osproc]
   # If this fails with: `Error: cannot open file: std/os`, see
   # https://github.com/nim-lang/Nim/pull/14291 for explanation + how to fix.
 
+when defined(nimPreviewSlimSystem):
+  import std/[assertions, syncio]
+
 import tools / kochdocs
 import tools / deps
 

lib/std/private/gitutils.nim

@@ -6,6 +6,9 @@ internal API for now, API subject to change
 
 import std/[os, osproc, strutils, tempfiles]
 
+when defined(nimPreviewSlimSystem):
+  import std/[assertions, syncio]
+
 const commitHead* = "HEAD"
 
 template retryCall*(maxRetry = 3, backoffDuration = 1.0, call: untyped): bool =

tests/tools/compile/tkoch.nim

@@ -0,0 +1,5 @@
+discard """
+  action: compile
+"""
+
+include koch

tests/tools/config.nims

@@ -0,0 +1 @@
+--d:nimPreviewSlimSystem

tests/tools/tnimgrep.nim

@@ -8,7 +8,9 @@ discard """
 """
 ## Authors: quantimnot, a-mr
 
-import osproc, os, streams, unittest, strutils
+import std/[osproc, os, streams, unittest, strutils]
+
+import std/syncio
 
 #=======
 # setup

tools/deps.nim

@@ -1,6 +1,9 @@
-import os, uri, strformat, strutils
+import std/[os, uri, strformat, strutils]
 import std/private/gitutils
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 proc exec(cmd: string) =
   echo "deps.cmd: " & cmd
   let status = execShellCmd(cmd)

tools/detect/detect.nim

@@ -12,7 +12,10 @@
 # The second one is more portable, and less semantically correct. It only works
 # when there's a backing C compiler available as well, preventing standalone
 # compilation.
-import os, strutils
+import std/[os, strutils]
+
+when defined(nimPreviewSlimSystem):
+  import std/syncio
 
 when defined(openbsd) or defined(freebsd) or defined(netbsd):
   const

tools/kochdocs.nim

@@ -1,6 +1,10 @@
 ## Part of 'koch' responsible for the documentation generation.
 
-import os, strutils, osproc, sets, pathnorm, sequtils
+import std/[os, strutils, osproc, sets, pathnorm, sequtils]
+
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 # XXX: Remove this feature check once the csources supports it.
 when defined(nimHasCastPragmaBlocks):
   import std/pegs