Change styleCheck to ignore foreign packages (#19822)

* Change `styleCheck` to ignore foreign packages

* Symbols from foreign packages are now ignored.
* Fixed `styleCheck` violations in `compiler` package.
* Added symbol ownership to custom annotation pragmas.
* Minor refactors to cleanup style check callsites.
* Minor internal documentation of reasons why a symbol isn't checked.

Style violations were fixed in the compiler after thet were exposed by
the changes. The compiler wouldn't compile otherwise.

Symbol ownership for custom pragma annotations is needed for checking
the annotation's style. A NPE was raised otherwise.

Fixes #10201
See also nim-lang/RFCs#456

* Fix a misunderstanding about excluding field style checks

I had refactored the callsites of `styleCheckUse` to apply the DRY
principle, but I misunderstood the field access handling in a template
as a general case. This corrects it.

* Fix some `styleCheck` violations in `compiler/evalffi`

The violations were exposed in CI when the compiler was built with
libffi.

* Removed some uneeded transitionary code

* Add changelog entry

Co-authored-by: quantimnot <quantimnot@users.noreply.github.com>

compiler/linter.nim

@@ -12,7 +12,8 @@
 import std/strutils
 from std/sugar import dup
 
-import options, ast, msgs, idents, lineinfos, wordrecg, astmsgs
+import options, ast, msgs, idents, lineinfos, wordrecg, astmsgs, semdata, packages
+export packages
 
 const
   Letters* = {'a'..'z', 'A'..'Z', '0'..'9', '\x80'..'\xFF', '_'}
@@ -85,24 +86,32 @@ proc differ*(line: string, a, b: int, x: string): string =
       result = y
 
 proc nep1CheckDefImpl(conf: ConfigRef; info: TLineInfo; s: PSym; k: TSymKind) =
-  # operators stay as they are:
-  if k in {skResult, skTemp} or s.name.s[0] notin Letters: return
-  if k in {skType, skGenericParam} and sfAnon in s.flags: return
-  if s.typ != nil and s.typ.kind == tyTypeDesc: return
-  if {sfImportc, sfExportc} * s.flags != {}: return
-  if optStyleCheck notin s.options: return
   let beau = beautifyName(s.name.s, k)
   if s.name.s != beau:
     lintReport(conf, info, beau, s.name.s)
 
-template styleCheckDef*(conf: ConfigRef; info: TLineInfo; s: PSym; k: TSymKind) =
-  if {optStyleHint, optStyleError} * conf.globalOptions != {} and optStyleUsages notin conf.globalOptions:
-    nep1CheckDefImpl(conf, info, s, k)
+template styleCheckDef*(ctx: PContext; info: TLineInfo; sym: PSym; k: TSymKind) =
+  ## Check symbol definitions adhere to NEP1 style rules.
+  if optStyleCheck in ctx.config.options and # ignore if styleChecks are off
+     hintName in ctx.config.notes and # ignore if name checks are not requested
+     ctx.config.belongsToProjectPackage(ctx.module) and # ignore foreign packages
+     optStyleUsages notin ctx.config.globalOptions and # ignore if requested to only check name usage
+     sym.kind != skResult and # ignore `result`
+     sym.kind != skTemp and # ignore temporary variables created by the compiler
+     sym.name.s[0] in Letters and # ignore operators TODO: what about unicode symbols???
+     k notin {skType, skGenericParam} and # ignore types and generic params
+     (sym.typ == nil or sym.typ.kind != tyTypeDesc) and # ignore `typedesc`
+     {sfImportc, sfExportc} * sym.flags == {} and # ignore FFI
+     sfAnon notin sym.flags: # ignore if created by compiler
+    nep1CheckDefImpl(ctx.config, info, sym, k)
 
-template styleCheckDef*(conf: ConfigRef; info: TLineInfo; s: PSym) =
-  styleCheckDef(conf, info, s, s.kind)
-template styleCheckDef*(conf: ConfigRef; s: PSym) =
-  styleCheckDef(conf, s.info, s, s.kind)
+template styleCheckDef*(ctx: PContext; info: TLineInfo; s: PSym) =
+  ## Check symbol definitions adhere to NEP1 style rules.
+  styleCheckDef(ctx, info, s, s.kind)
+
+template styleCheckDef*(ctx: PContext; s: PSym) =
+  ## Check symbol definitions adhere to NEP1 style rules.
+  styleCheckDef(ctx, s.info, s, s.kind)
 
 proc differs(conf: ConfigRef; info: TLineInfo; newName: string): string =
   let line = sourceLine(conf, info)
@@ -116,23 +125,27 @@ proc differs(conf: ConfigRef; info: TLineInfo; newName: string): string =
   let last = first+identLen(line, first)-1
   result = differ(line, first, last, newName)
 
-proc styleCheckUse*(conf: ConfigRef; info: TLineInfo; s: PSym) =
-  if info.fileIndex.int < 0: return
-  # we simply convert it to what it looks like in the definition
-  # for consistency
-
-  # operators stay as they are:
-  if s.kind == skTemp or s.name.s[0] notin Letters or sfAnon in s.flags:
-    return
-
+proc styleCheckUseImpl(conf: ConfigRef; info: TLineInfo; s: PSym) =
   let newName = s.name.s
   let badName = differs(conf, info, newName)
   if badName.len > 0:
-    # special rules for historical reasons
-    let forceHint = badName == "nnkArgList" and newName == "nnkArglist" or badName == "nnkArglist" and newName == "nnkArgList"
-    lintReport(conf, info, newName, badName, forceHint = forceHint, extraMsg = "".dup(addDeclaredLoc(conf, s)))
+    lintReport(conf, info, newName, badName, "".dup(addDeclaredLoc(conf, s)))
 
-proc checkPragmaUse*(conf: ConfigRef; info: TLineInfo; w: TSpecialWord; pragmaName: string) =
+template styleCheckUse*(ctx: PContext; info: TLineInfo; sym: PSym) =
+  ## Check symbol uses match their definition's style.
+  if {optStyleHint, optStyleError} * ctx.config.globalOptions != {} and # ignore if styleChecks are off
+     hintName in ctx.config.notes and # ignore if name checks are not requested
+     ctx.config.belongsToProjectPackage(ctx.module) and # ignore foreign packages
+     sym.kind != skTemp and # ignore temporary variables created by the compiler
+     sym.name.s[0] in Letters and # ignore operators TODO: what about unicode symbols???
+     sfAnon notin sym.flags: # ignore temporary variables created by the compiler
+    styleCheckUseImpl(ctx.config, info, sym)
+
+proc checkPragmaUseImpl(conf: ConfigRef; info: TLineInfo; w: TSpecialWord; pragmaName: string) =
   let wanted = $w
   if pragmaName != wanted:
     lintReport(conf, info, wanted, pragmaName)
+
+template checkPragmaUse*(conf: ConfigRef; info: TLineInfo; w: TSpecialWord; pragmaName: string) =
+  if {optStyleHint, optStyleError} * conf.globalOptions != {}:
+    checkPragmaUseImpl(conf, info, w, pragmaName)