bootstrap the compiler with nimPreviewSlimSystem (#20176)

* bootstrap the compiler with nimPreviewSlimSystem

* threads

compiler/depends.nim

@@ -16,6 +16,10 @@ import modulegraphs
 import std/[os, strutils, parseutils]
 import std/private/globs
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
+
 type
   TGen = object of PPassContext
     module: PSym

compiler/docgen.nim

@@ -23,6 +23,10 @@ from uri import encodeUrl
 from std/private/globs import nativeToUnixPath
 from nodejs import findNodeJs
 
+when defined(nimPreviewSlimSystem):
+  import std/[assertions, syncio]
+
+
 const
   exportSection = skField
   docCmdSkip = "skip"

compiler/jsgen.nim

@@ -37,6 +37,10 @@ import
 
 import json, sets, math, tables, intsets, strutils
 
+when defined(nimPreviewSlimSystem):
+  import std/[assertions, syncio]
+
+
 type
   TJSGen = object of PPassContext
     module: PSym

compiler/nim.cfg

@@ -5,6 +5,7 @@ hint[XDeclaredButNotUsed]:off
 define:booting
 define:nimcore
 define:nimPreviewFloatRoundtrip
+define:nimPreviewSlimSystem
 
 #import:"$projectpath/testability"
 

compiler/packages.nim

@@ -16,6 +16,10 @@
 
 import "." / [options, ast, lineinfos, idents, pathutils, msgs]
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
+
 proc getPackage*(conf: ConfigRef; cache: IdentCache; fileIdx: FileIndex): PSym =
   ## Return a new package symbol.
   ## 

compiler/renderverbatim.nim

@@ -2,6 +2,10 @@ import strutils
 
 import ast, options, msgs
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
+
 const isDebug = false
 when isDebug:
   import renderer

compiler/typesrenderer.nim

@@ -9,6 +9,10 @@
 
 import renderer, strutils, ast, types
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
+
 const defaultParamSeparator* = ","
 
 template mayNormalize(s: string): string =

compiler/vmops.nim

@@ -32,7 +32,7 @@ from system/formatfloat import addFloatRoundtrip, addFloatSprintf
 
 
 when defined(nimPreviewSlimSystem):
-  import std/[syncio, assertions]
+  import std/syncio
 
 
 # There are some useful procs in vmconv.