fixes #20397; fixes stylecheck regression (#20398)

* fixes  #20397; fixes stylecheck

* add testcase

compiler/linter.nim

@@ -93,6 +93,7 @@ proc nep1CheckDefImpl(conf: ConfigRef; info: TLineInfo; s: PSym; k: TSymKind) =
 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
+     {optStyleHint, optStyleError} * ctx.config.globalOptions != {} and # check only if hint/error is enabled
      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

tests/stylecheck/t20397.nim

@@ -0,0 +1,4 @@
+{.hintAsError[Name]:on.}
+var a_b = 1
+discard a_b
+{.hintAsError[Name]:off.}

tests/stylecheck/t20397_1.nim

@@ -0,0 +1,8 @@
+discard """
+  matrix: "--styleCheck:off"
+"""
+
+{.hintAsError[Name]:on.}
+var a_b = 1
+discard a_b
+{.hintAsError[Name]:off.}

tests/stylecheck/t20397_2.nim

@@ -0,0 +1,7 @@
+discard """
+  errormsg: "'a_b' should be: 'aB'"
+  matrix: "--styleCheck:error"
+"""
+
+var a_b = 1
+discard a_b