FavourNestedFunctions: hook cfg & add docs

Updated Configuration.fs and fsharplint.json to include
FavourNestedFunctions rule. Added docs.

Author: webwarrior-ws

docs/content/how-tos/rule-configuration.md

@@ -122,3 +122,4 @@ The following rules can be specified for linting.
 - [SuggestUseAutoProperty (FL0079)](rules/FL0079.html)
 - [UnnestedFunctionNames (FL0080)](rules/FL0080.html)
 - [NestedFunctionNames (FL0081)](rules/FL0081.html)
+- [FavourNestedFunctions (FL0082)](rules/FL0082.html)

docs/content/how-tos/rules/FL0082.md

@@ -0,0 +1,31 @@
+---
+title: FL0082
+category: how-to
+hide_menu: true
+---
+
+# FavourNestedFunctions (FL0082)
+
+*Introduced in `0.23.0`*
+
+## Cause
+
+Prefer using local (nested) functions over private module-level functions.
+
+## Rationale
+
+With a nested function, one can clearly see from reading the code that there is only one consumer of the function.
+The code being this way becomes more streamlined.
+Code is also more concise because nested functions don't need accessibility modifiers.
+
+## How To Fix
+
+Move private function inside function that uses it.
+
+## Rule Settings
+
+    {
+        "FavourNestedFunctions": {
+            "enabled": false
+        }
+    }

src/FSharpLint.Core/Application/Configuration.fs

@@ -322,7 +322,8 @@ type ConventionsConfig =
       binding:BindingConfig option
       favourReRaise:EnabledConfig option
       favourConsistentThis:RuleConfig<FavourConsistentThis.Config> option
-      suggestUseAutoProperty:EnabledConfig option}
+      suggestUseAutoProperty:EnabledConfig option
+      favourNestedFunctions:EnabledConfig option }
 with
     member this.Flatten() =
         [|
@@ -344,6 +345,7 @@ with
             this.numberOfItems |> Option.map (fun config -> config.Flatten()) |> Option.toArray |> Array.concat
             this.binding |> Option.map (fun config -> config.Flatten()) |> Option.toArray |> Array.concat
             this.suggestUseAutoProperty |> Option.bind (constructRuleIfEnabled SuggestUseAutoProperty.rule) |> Option.toArray
+            this.favourNestedFunctions |> Option.bind (constructRuleIfEnabled FavourNestedFunctions.rule) |> Option.toArray
         |] |> Array.concat
 
 type TypographyConfig =
@@ -463,7 +465,8 @@ type Configuration =
       TrailingNewLineInFile:EnabledConfig option
       NoTabCharacters:EnabledConfig option
       NoPartialFunctions:RuleConfig<NoPartialFunctions.Config> option
-      SuggestUseAutoProperty:EnabledConfig option }
+      SuggestUseAutoProperty:EnabledConfig option
+      FavourNestedFunctions:EnabledConfig option }
 with
     static member Zero = {
         Global = None
@@ -551,6 +554,7 @@ with
         NoTabCharacters = None
         NoPartialFunctions = None
         SuggestUseAutoProperty = None
+        FavourNestedFunctions = None
     }
 
 // fsharplint:enable RecordFieldNames
@@ -701,6 +705,7 @@ let flattenConfig (config:Configuration) =
             config.TrailingNewLineInFile |> Option.bind (constructRuleIfEnabled TrailingNewLineInFile.rule)
             config.NoTabCharacters |> Option.bind (constructRuleIfEnabled NoTabCharacters.rule)
             config.NoPartialFunctions |> Option.bind (constructRuleWithConfig NoPartialFunctions.rule)
+            config.FavourNestedFunctions |> Option.bind (constructRuleIfEnabled FavourNestedFunctions.rule)
         |] |> Array.choose id
 
     if config.NonPublicValuesNames.IsSome &&

src/FSharpLint.Core/fsharplint.json

@@ -323,6 +323,7 @@
             "additionalPartials": []
         }
     },
+    "favourNestedFunctions": { "enabled": false },
     "hints": {
         "add": [
             "not (a =  b) ===> a <> b",