move assertions out of system (#19599)

compiler/aliases.nim

@@ -12,6 +12,9 @@
 import
   ast, astalgo, types, trees, intsets
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 type
   TAnalysisResult* = enum
     arNo, arMaybe, arYes

compiler/ast.nim

@@ -13,6 +13,9 @@ import
   lineinfos, hashes, options, ropes, idents, int128, tables
 from strutils import toLowerAscii
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 export int128
 
 type

compiler/astalgo.nim

@@ -15,6 +15,9 @@ import
   ast, hashes, intsets, strutils, options, lineinfos, ropes, idents, rodutils,
   msgs
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 proc hashNode*(p: RootRef): Hash
 proc treeToYaml*(conf: ConfigRef; n: PNode, indent: int = 0, maxRecDepth: int = - 1): Rope
   # Convert a tree into its YAML representation; this is used by the

compiler/bitsets.nim

@@ -10,6 +10,9 @@
 # this unit handles Nim sets; it implements bit sets
 # the code here should be reused in the Nim standard library
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 type
   ElemType = byte
   TBitSet* = seq[ElemType]    # we use byte here to avoid issues with

compiler/btrees.nim

@@ -10,6 +10,9 @@
 ## BTree implementation with few features, but good enough for the
 ## Nim compiler's needs.
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 const
   M = 512    # max children per B-tree node = M-1
              # (must be even and greater than 2)

compiler/ccgutils.nim

@@ -13,6 +13,9 @@ import
   ast, types, hashes, strutils, msgs, wordrecg,
   platform, trees, options, cgendata
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 proc getPragmaStmt*(n: PNode, w: TSpecialWord): PNode =
   case n.kind
   of nkStmtList:

compiler/cgen.nim

@@ -17,6 +17,10 @@ import
   lowerings, tables, sets, ndi, lineinfos, pathutils, transf,
   injectdestructors, astmsgs
 
+
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 when not defined(leanCompiler):
   import spawn, semparallel
 

compiler/cgmeth.nim

@@ -13,6 +13,10 @@ import
   intsets, options, ast, msgs, idents, renderer, types, magicsys,
   sempass2, strutils, modulegraphs, lineinfos
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
+
 proc genConv(n: PNode, d: PType, downcast: bool; conf: ConfigRef): PNode =
   var dest = skipTypes(d, abstractPtrs)
   var source = skipTypes(n.typ, abstractPtrs)

compiler/closureiters.nim

@@ -133,6 +133,9 @@ import
   renderer, magicsys, lowerings, lambdalifting, modulegraphs, lineinfos,
   tables, options
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 type
   Ctx = object
     g: ModuleGraph

compiler/commands.nim

@@ -31,6 +31,9 @@ import
 
 from ast import setUseIc, eqTypeFlags, tfGcSafe, tfNoSideEffect
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 # but some have deps to imported modules. Yay.
 bootSwitch(usedTinyC, hasTinyCBackend, "-d:tinyc")
 bootSwitch(usedFFI, hasFFI, "-d:nimHasLibFFI")

compiler/concepts.nim

@@ -15,6 +15,9 @@ import ast, astalgo, semdata, lookups, lineinfos, idents, msgs, renderer, types,
 
 from magicsys import addSonSkipIntLit
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 const
   logBindings = false
 

compiler/dfa.nim

@@ -32,6 +32,9 @@
 import ast, intsets, lineinfos, renderer
 import std/private/asciitables
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 type
   InstrKind* = enum
     goto, fork, def, use

compiler/enumtostr.nim

@@ -1,6 +1,10 @@
 
 import ast, idents, lineinfos, modulegraphs, magicsys
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
+
 proc genEnumToStrProc*(t: PType; info: TLineInfo; g: ModuleGraph; idgen: IdGenerator): PSym =
   result = newSym(skProc, getIdent(g.cache, "$"), nextSymId idgen, t.owner, info)
 

compiler/errorhandling.nim

@@ -12,6 +12,9 @@
 
 import ast, renderer, options, strutils, types
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 type
   ErrorKind* = enum ## expand as you need.
     RawTypeMismatchError

compiler/extccomp.nim

@@ -16,6 +16,9 @@ import ropes, platform, condsyms, options, msgs, lineinfos, pathutils
 
 import std/[os, strutils, osproc, sha1, streams, sequtils, times, strtabs, json, jsonutils, sugar]
 
+when defined(nimPreviewSlimSystem):
+  import std/syncio
+
 type
   TInfoCCProp* = enum         # properties of the C compiler:
     hasSwitchRange,           # CC allows ranges in switch statements (GNU C)

compiler/gorgeimpl.nim

@@ -12,6 +12,9 @@
 import msgs, std / sha1, os, osproc, streams, options,
   lineinfos, pathutils
 
+when defined(nimPreviewSlimSystem):
+  import std/syncio
+
 proc readOutput(p: Process): (string, int) =
   result[0] = ""
   var output = p.outputStream

compiler/guards.nim

@@ -12,6 +12,9 @@
 import ast, astalgo, msgs, magicsys, nimsets, trees, types, renderer, idents,
   saturate, modulegraphs, options, lineinfos, int128
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 const
   someEq = {mEqI, mEqF64, mEqEnum, mEqCh, mEqB, mEqRef, mEqProc,
     mEqStr, mEqSet, mEqCString}

compiler/hlo.nim

@@ -9,6 +9,9 @@
 
 # This include implements the high level optimization pass.
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 proc hlo(c: PContext, n: PNode): PNode
 
 proc evalPattern(c: PContext, n, orig: PNode): PNode =

compiler/ic/bitabs.nim

@@ -3,6 +3,9 @@
 
 import hashes, rodfiles
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 type
   LitId* = distinct uint32
 

compiler/ic/cbackend.nim

@@ -20,6 +20,9 @@
 
 import std/packedsets, algorithm, tables
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 import ".."/[ast, options, lineinfos, modulegraphs, cgendata, cgen,
   pathutils, extccomp, msgs]
 

compiler/ic/dce.nim

@@ -10,6 +10,10 @@
 ## Dead code elimination (=DCE) for IC.
 
 import std/[intsets, tables]
+
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 import ".." / [ast, options, lineinfos, types]
 
 import packed_ast, ic, bitabs

compiler/ic/ic.nim

@@ -14,6 +14,9 @@ import ".." / [ast, idents, lineinfos, msgs, ropes, options,
 #import ".." / [renderer, astalgo]
 from os import removeFile, isAbsolute
 
+when defined(nimPreviewSlimSystem):
+  import std/[syncio, assertions]
+
 type
   PackedConfig* = object
     backend: TBackend

compiler/ic/integrity.nim

@@ -11,6 +11,10 @@
 ## The set must cover a complete Nim project.
 
 import sets
+
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 import ".." / [ast, modulegraphs]
 import packed_ast, bitabs, ic
 

compiler/ic/navigator.nim

@@ -16,6 +16,9 @@ import sets
 from os import nil
 from std/private/miscdollars import toLocation
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 import ".." / [ast, modulegraphs, msgs, options]
 import packed_ast, bitabs, ic
 

compiler/ic/packed_ast.nim

@@ -16,6 +16,9 @@ import hashes, tables, strtabs
 import bitabs
 import ".." / [ast, options]
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 type
   SymId* = distinct int32
   ModuleId* = distinct int32

compiler/ic/replayer.nim

@@ -16,6 +16,9 @@ import ".." / [ast, modulegraphs, trees, extccomp, btrees,
 
 import tables
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 import packed_ast, ic, bitabs
 
 proc replayStateChanges*(module: PSym; g: ModuleGraph) =

compiler/ic/rodfiles.nim

@@ -16,6 +16,9 @@
 
 from typetraits import supportsCopyMem
 
+when defined(nimPreviewSlimSystem):
+  import std/[syncio, assertions]
+
 ## Overview
 ## ========
 ## `RodFile` represents a Rod File (versioned binary format), and the

compiler/idents.nim

@@ -14,6 +14,9 @@
 import
   hashes, wordrecg
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 type
   PIdent* = ref TIdent
   TIdent*{.acyclic.} = object

compiler/importer.nim

@@ -15,6 +15,9 @@ import
   modulegraphs, wordrecg, tables
 from strutils import `%`
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 proc readExceptSet*(c: PContext, n: PNode): IntSet =
   assert n.kind in {nkImportExceptStmt, nkExportExceptStmt}
   result = initIntSet()

compiler/injectdestructors.nim

@@ -19,6 +19,9 @@ import
   lineinfos, parampatterns, sighashes, liftdestructors, optimizer,
   varpartitions
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 from trees import exprStructuralEquivalent, getRoot
 
 type

compiler/int128.nim

@@ -5,6 +5,9 @@
 
 from math import trunc
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 type
   Int128* = object
     udata: array[4, uint32]

compiler/isolation_check.nim

@@ -13,6 +13,9 @@
 import
   ast, types, renderer, intsets
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 proc canAlias(arg, ret: PType; marker: var IntSet): bool
 
 proc canAliasN(arg: PType; n: PNode; marker: var IntSet): bool =

compiler/lambdalifting.nim

@@ -14,6 +14,9 @@ import
   idents, renderer, types, magicsys, lowerings, tables, modulegraphs, lineinfos,
   transf, liftdestructors, typeallowed
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 discard """
   The basic approach is that captured vars need to be put on the heap and
   that the calling chain needs to be explicitly modelled. Things to consider:

compiler/lexer.nim

@@ -19,6 +19,9 @@ import
   hashes, options, msgs, strutils, platform, idents, nimlexbase, llstream,
   wordrecg, lineinfos, pathutils, parseutils
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 const
   MaxLineLength* = 80         # lines longer than this lead to a warning
   numChars*: set[char] = {'0'..'9', 'a'..'z', 'A'..'Z'}

compiler/liftdestructors.nim

@@ -15,6 +15,9 @@ import modulegraphs, lineinfos, idents, ast, renderer, semdata,
 
 from trees import isCaseObj
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 type
   TLiftCtx = object
     g: ModuleGraph

compiler/llstream.nim

@@ -12,6 +12,9 @@
 import
   pathutils
 
+when defined(nimPreviewSlimSystem):
+  import std/syncio
+
 # support `useGnuReadline`, `useLinenoise` for backwards compatibility
 const hasRstdin = (defined(nimUseLinenoise) or defined(useLinenoise) or defined(useGnuReadline)) and
   not defined(windows)

compiler/lookups.nim

@@ -9,6 +9,10 @@
 
 # This module implements lookup helpers.
 import std/[algorithm, strutils]
+
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 import
   intsets, ast, astalgo, idents, semdata, types, msgs, options,
   renderer, nimfix/prettybase, lineinfos, modulegraphs, astmsgs

compiler/lowerings.nim

@@ -15,6 +15,9 @@ const
 import ast, astalgo, types, idents, magicsys, msgs, options, modulegraphs,
   lineinfos
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 proc newDeref*(n: PNode): PNode {.inline.} =
   result = newNodeIT(nkHiddenDeref, n.info, n.typ[0])
   result.add n

compiler/main.nim

@@ -22,6 +22,10 @@ import
   modules,
   modulegraphs, lineinfos, pathutils, vmprofiler
 
+
+when defined(nimPreviewSlimSystem):
+  import std/[syncio, assertions]
+
 import ic / [cbackend, integrity, navigator]
 from ic / ic import rodViewer
 

compiler/modulegraphs.nim

@@ -15,6 +15,9 @@ import intsets, tables, hashes, md5_old
 import ast, astalgo, options, lineinfos,idents, btrees, ropes, msgs, pathutils
 import ic / [packed_ast, ic]
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 type
   SigHash* = distinct MD5Digest
 

compiler/modules.nim

@@ -14,6 +14,9 @@ import
   idents, lexer, passes, syntaxes, llstream, modulegraphs,
   lineinfos, pathutils, tables
 
+when defined(nimPreviewSlimSystem):
+  import std/[syncio, assertions]
+
 import ic / replayer
 
 proc resetSystemArtifacts*(g: ModuleGraph) =

compiler/msgs.nim

@@ -12,6 +12,10 @@ import
   std/private/miscdollars,
   options, ropes, lineinfos, pathutils, strutils2
 
+when defined(nimPreviewSlimSystem):
+  import std/[syncio, assertions]
+
+
 type InstantiationInfo* = typeof(instantiationInfo())
 template instLoc*(): InstantiationInfo = instantiationInfo(-2, fullPaths = true)
 

compiler/ndi.nim

@@ -12,6 +12,9 @@
 
 import ast, msgs, ropes, options, pathutils
 
+when defined(nimPreviewSlimSystem):
+  import std/[syncio, assertions]
+
 type
   NdiFile* = object
     enabled: bool

compiler/nilcheck.nim

@@ -10,6 +10,9 @@
 import ast, renderer, intsets, tables, msgs, options, lineinfos, strformat, idents, treetab, hashes
 import sequtils, strutils, sets
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 # IMPORTANT: notes not up to date, i'll update this comment again
 #
 # notes:

compiler/nim.nim

@@ -8,6 +8,10 @@
 #
 
 import std/[os, strutils, parseopt]
+
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 when defined(windows) and not defined(nimKochBootstrap):
   # remove workaround pending bootstrap >= 1.5.1
   # refs https://github.com/nim-lang/Nim/issues/18334#issuecomment-867114536

compiler/nimblecmd.nim

@@ -12,6 +12,9 @@
 import parseutils, strutils, os, options, msgs, sequtils, lineinfos, pathutils,
   std/sha1, tables
 
+when defined(nimPreviewSlimSystem):
+  import std/[syncio, assertions]
+
 proc addPath*(conf: ConfigRef; path: AbsoluteDir, info: TLineInfo) =
   if not conf.searchPaths.contains(path):
     conf.searchPaths.insert(path, 0)

compiler/nimconf.nim

@@ -13,6 +13,9 @@ import
   llstream, commands, os, strutils, msgs, lexer, ast,
   options, idents, wordrecg, strtabs, lineinfos, pathutils, scriptconfig
 
+when defined(nimPreviewSlimSystem):
+  import std/syncio
+
 # ---------------- configuration file parser -----------------------------
 # we use Nim's lexer here to save space and work
 

compiler/nimlexbase.nim

@@ -15,6 +15,9 @@
 import
   llstream, strutils
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 const
   Lrz* = ' '
   Apo* = '\''

compiler/nimpaths.nim

@@ -19,6 +19,10 @@ Unstable API
 
 import os, strutils
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
+
 const
   docCss* = "$nimr/doc/nimdoc.css"
   docHackNim* = "$nimr/tools/dochack/dochack.nim"

compiler/nimsets.nim

@@ -12,6 +12,9 @@
 import
   ast, astalgo, lineinfos, bitsets, types, options
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 proc inSet*(s: PNode, elem: PNode): bool =
   assert s.kind == nkCurly
   if s.kind != nkCurly:

compiler/options.nim

@@ -14,6 +14,11 @@ import
 from terminal import isatty
 from times import utc, fromUnix, local, getTime, format, DateTime
 from std/private/globs import nativeToUnixPath
+
+when defined(nimPreviewSlimSystem):
+  import std/[syncio, assertions]
+
+
 const
   hasTinyCBackend* = defined(tinyc)
   useEffectSystem* = true

compiler/parser.nim

@@ -36,6 +36,9 @@ import
 when defined(nimpretty):
   import layouter
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 type
   Parser* = object            # A Parser object represents a file that
                               # is being parsed

compiler/passes.nim

@@ -16,6 +16,9 @@ import
   syntaxes, modulegraphs, reorder,
   lineinfos, pathutils
 
+when defined(nimPreviewSlimSystem):
+  import std/syncio
+
 type
   TPassData* = tuple[input: PNode, closeOutput: PNode]
 

compiler/pathutils.nim

@@ -13,7 +13,7 @@
 import os, pathnorm
 
 when defined(nimPreviewSlimSystem):
-  import std/syncio
+  import std/[syncio, assertions]
 
 type
   AbsoluteFile* = distinct string

compiler/patterns.nim

@@ -13,6 +13,9 @@
 import
   ast, types, semdata, sigmatch, idents, aliases, parampatterns, trees
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 type
   TPatternContext = object
     owner: PSym

compiler/platform.nim

@@ -16,6 +16,10 @@
 import
   strutils
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
+
 type
   TSystemOS* = enum # Also add OS in initialization section and alias
                     # conditionals to condsyms (end of module).

compiler/pragmas.nim

@@ -14,6 +14,9 @@ import
   wordrecg, ropes, options, strutils, extccomp, math, magicsys, trees,
   types, lookups, lineinfos, pathutils, linter
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 from ic / ic import addCompilerProc
 
 const

compiler/renderer.nim

@@ -17,6 +17,9 @@ when defined(nimHasUsed):
 import
   lexer, options, idents, strutils, ast, msgs, lineinfos
 
+when defined(nimPreviewSlimSystem):
+  import std/[syncio, assertions]
+
 type
   TRenderFlag* = enum
     renderNone, renderNoBody, renderNoComments, renderDocComments,

compiler/reorder.nim

@@ -4,6 +4,9 @@ import
   msgs, modulegraphs, syntaxes, options, modulepaths,
   lineinfos
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 type
   DepN = ref object
     pnode: PNode

compiler/rodutils.nim

@@ -10,6 +10,9 @@
 ## Serialization utilities for the compiler.
 import strutils, math
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 # bcc on windows doesn't have C99 functions
 when defined(windows) and defined(bcc):
   {.emit: """#if defined(_MSC_VER) && _MSC_VER < 1900

compiler/ropes.nim

@@ -60,6 +60,10 @@ import
 
 from pathutils import AbsoluteFile
 
+when defined(nimPreviewSlimSystem):
+  import std/[assertions, syncio]
+
+
 type
   FormatStr* = string  # later we may change it to CString for better
                        # performance of the code generator (assignments

compiler/scriptconfig.nim

@@ -16,6 +16,9 @@ import
   os, times, osproc, wordrecg, strtabs, modulegraphs,
   pathutils
 
+when defined(nimPreviewSlimSystem):
+  import std/syncio
+
 # we support 'cmpIgnoreStyle' natively for efficiency:
 from strutils import cmpIgnoreStyle, contains
 

compiler/semdata.nim

@@ -11,6 +11,9 @@
 
 import tables
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 import
   intsets, options, ast, astalgo, msgs, idents, renderer,
   magicsys, vmdef, modulegraphs, lineinfos, sets, pathutils

compiler/semfold.nim

@@ -17,6 +17,9 @@ import
 
 from system/memory import nimCStrLen
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 proc errorType*(g: ModuleGraph): PType =
   ## creates a type representing an error state
   result = newType(tyError, nextTypeId(g.idgen), g.owners[^1])

compiler/sempass2.nim

@@ -12,6 +12,9 @@ import
   wordrecg, strutils, options, guards, lineinfos, semfold, semdata,
   modulegraphs, varpartitions, typeallowed, nilcheck, errorhandling, tables
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 when defined(useDfa):
   import dfa
 

compiler/semtypinst.nim

@@ -14,6 +14,9 @@ import ast, astalgo, msgs, types, magicsys, semdata, renderer, options,
 
 from concepts import makeTypeDesc
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 const tfInstClearedFlags = {tfHasMeta, tfUnresolved}
 
 proc checkPartialConstructedType(conf: ConfigRef; info: TLineInfo, t: PType) =

compiler/sighashes.nim

@@ -13,6 +13,10 @@ import ast, tables, ropes, md5_old, modulegraphs
 from hashes import Hash
 import types
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
+
 proc `&=`(c: var MD5Context, s: string) = md5Update(c, s, s.len)
 proc `&=`(c: var MD5Context, ch: char) =
   # XXX suspicious code here; relies on ch being zero terminated?

compiler/sigmatch.nim

@@ -15,6 +15,9 @@ import
   magicsys, idents, lexer, options, parampatterns, strutils, trees,
   linter, lineinfos, lowerings, modulegraphs, concepts
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 type
   MismatchKind* = enum
     kUnknown, kAlreadyGiven, kUnknownNamedParam, kTypeMismatch, kVarNeeded,

compiler/syntaxes.nim

@@ -13,6 +13,9 @@ import
   strutils, llstream, ast, idents, lexer, options, msgs, parser,
   filters, filter_tmpl, renderer, lineinfos, pathutils
 
+when defined(nimPreviewSlimSystem):
+  import std/[syncio, assertions]
+
 export Parser, parseAll, parseTopLevelStmt, closeParser
 
 type

compiler/transf.nim

@@ -24,6 +24,9 @@ import
   lowerings, liftlocals,
   modulegraphs, lineinfos
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 proc transformBody*(g: ModuleGraph; idgen: IdGenerator, prc: PSym, cache: bool): PNode
 
 import closureiters, lambdalifting

compiler/treetab.nim

@@ -12,6 +12,9 @@
 import
   hashes, ast, astalgo, types
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 proc hashTree*(n: PNode): Hash =
   if n.isNil:
     return

compiler/typeallowed.nim

@@ -13,6 +13,9 @@
 import
   intsets, ast, renderer, options, semdata, types
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 type
   TTypeAllowedFlag* = enum
     taField,

compiler/types.nim

@@ -13,6 +13,9 @@ import
   intsets, ast, astalgo, trees, msgs, strutils, platform, renderer, options,
   lineinfos, int128, modulegraphs, astmsgs
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 type
   TPreferedDesc* = enum
     preferName, # default

compiler/varpartitions.nim

@@ -32,6 +32,9 @@ import ast, types, lineinfos, options, msgs, renderer, typeallowed, modulegraphs
 from trees import getMagic, isNoSideEffectPragma, stupidStmtListExpr
 from isolation_check import canAlias
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 type
   AbstractTime = distinct int
 

compiler/vmdeps.nim

@@ -10,6 +10,9 @@
 import ast, types, msgs, os, options, idents, lineinfos
 from pathutils import AbsoluteFile
 
+when defined(nimPreviewSlimSystem):
+  import std/syncio
+
 proc opSlurp*(file: string, info: TLineInfo, module: PSym; conf: ConfigRef): string =
   try:
     var filename = parentDir(toFullPath(conf, info)) / file

compiler/vmgen.nim

@@ -29,6 +29,9 @@
 
 import tables
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 import
   strutils, ast, types, msgs, renderer, vmdef,
   intsets, magicsys, options, lowerings, lineinfos, transf, astmsgs

compiler/vmhooks.nim

@@ -9,6 +9,9 @@
 
 import pathutils
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 template setX(k, field) {.dirty.} =
   a.slots[a.ra].ensureKind(k)
   a.slots[a.ra].field = v

compiler/vmmarshal.nim

@@ -12,6 +12,9 @@
 import streams, json, intsets, tables, ast, astalgo, idents, types, msgs,
   options, lineinfos
 
+when defined(nimPreviewSlimSystem):
+  import std/assertions
+
 proc ptrToInt(x: PNode): int {.inline.} =
   result = cast[int](x) # don't skip alignment
 

compiler/vmops.nim

@@ -31,6 +31,10 @@ from std/osproc import nil
 from system/formatfloat import addFloatRoundtrip, addFloatSprintf
 
 
+when defined(nimPreviewSlimSystem):
+  import std/[syncio, assertions]
+
+
 # There are some useful procs in vmconv.
 import vmconv, vmmarshal