Add number of items based record multiline formatter (fsprojects#1169)

* Add new multiline formatter for arrays and lists

Add associated types (Size; MultilineFormatterType) and
isSmallExpression for choosing a formatter based on Size
given.

* Add EditorConfig parsing code

* Add tests

* Run formatter

* Remove quotes around string-enumeration

* Add documentation

* Rename LogicalSize.fs to LogicalSizeTests.fs

* Add logically sized record multiline formatter

* Remove spurious file

* Add tests for MultilineBlockBracketsOnSameColumn

* Fix typo in docs

* Run formatter

* Add config parsing tests

* Run formatter

* Add many more tests; some ignored due to open issues

* Run formatter

* Nitpicks

Co-authored-by: nojaf <[email protected]>

docs/Documentation.md

@@ -472,8 +472,9 @@ let WebApp =
 
 ### fsharp_max_record_width
 
-Control the maximum width for which records should be in one line.
-Default = 40.
+Control the maximum width for which records should be in one line. Default = 40.
+Requires `fsharp_record_multiline_formatter` to be `character_width` to take
+effect.
 
 `defaultConfig`
 
@@ -496,6 +497,99 @@ let myInstance =
       Length = 90 }
 ```
 
+### fsharp_max_record_number_of_items
+
+Control the maximum number of fields for which records should be in one line.
+Default = 1. Requires `fsharp_array_or_list_multiline_formatter` to be
+`number_of_items` to take effect.
+
+`defaultConfig`
+
+```fsharp
+type R = { x: int }
+
+type S = { x: int; y: string }
+
+type T = { x: int; y: string; z: float }
+
+let myRecord = { r = 3 }
+
+let myRecord' = { r with x = 3 }
+
+let myRecord'' = { r with x = 3; y = "hello" }
+
+let myRecord''' = { r with x = 3; y = "hello"; z = 0.0 }
+```
+
+`{ defaultConfig with MaxRecordSize = 2; RecordMultilineFormatter =
+MultilineFormatterType.NumberOfItems }`
+
+```fsharp
+type R = { x: int }
+
+type S = { x: int; y: string }
+
+type T =
+    { x: int
+      y: string
+      z: float }
+
+let myRecord = { r = 3 }
+
+let myRecord' = { r with x = 3 }
+
+let myRecord'' = { r with x = 3; y = "hello" }
+
+let myRecord''' =
+    { r with
+          x = 3
+          y = "hello"
+          z = 0.0 }
+```
+
+### fsharp_record_multiline_formatter
+
+Split records expressions/statements into multiple lines based on the given
+condition. `character_width` uses character count of the expression, controlled
+by `fsharp_max_record_width`. `number_of_items` uses the number of fields in the
+record, controlled by `fsharp_max_record_number_of_items`. Default =
+`character_width`. Note that in either case, record expressions/statements are
+still governed by `max_line_length`.
+
+`defaultConfig`
+
+```fsharp
+type R = { x: int }
+
+type S = { x: int; y: string }
+
+let myRecord = { r = 3 }
+
+let myRecord' = { r with x = 3 }
+
+let myRecord'' = { r with x = 3; y = "hello" }
+```
+
+`{ defaultConfig with RecordMultilineFormatter =
+MultilineFormatterType.NumberOfItems }`
+
+```fsharp
+type R = { x: int }
+
+type S =
+    { x: int
+      y: string }
+
+let myRecord = { x = 3 }
+
+let myRecord' = { r with x = 3 }
+
+let myRecord'' =
+    { r with
+          x = 3
+          y = "hello" }
+```
+
 ### fsharp_max_array_or_list_width
 
 Control the maximum width for which lists and arrays can be in one line. Default

src/Fantomas.Tests/Fantomas.Tests.fsproj

@@ -74,7 +74,8 @@
     <Compile Include="InterpolatedStringTests.fs" />
     <Compile Include="DotGetTests.fs" />
     <Compile Include="HashDirectiveTests.fs" />
-    <Compile Include="NumberOfItemsTests.fs" />
+    <Compile Include="NumberOfItemsListOrArrayTests.fs" />
+    <Compile Include="NumberOfItemsRecordTests.fs" />
     <Compile Include="SynExprNewTests.fs" />
   </ItemGroup>
   <ItemGroup>

src/Fantomas.Tests/FormatConfigEditorConfigurationFileTests.fs

@@ -204,7 +204,7 @@ let ``print default editorconfig settings`` () =
     |> printfn "%s"
 
 [<Test>]
-let ``number_of_items parsing tests`` () =
+let ``list and array number_of_items parsing tests`` () =
     let editorConfig = """
 [*.fs]
 fsharp_array_or_list_multiline_formatter = number_of_items
@@ -225,7 +225,7 @@ fsharp_max_array_or_list_number_of_items = 4
     == NumberOfItems
 
 [<Test>]
-let ``character_width parsing test with single option`` () =
+let ``list and array character_width parsing test with single option`` () =
     let editorConfig = """
 [*.fs]
 fsharp_max_array_or_list_width = 123
@@ -240,3 +240,40 @@ fsharp_max_array_or_list_width = 123
         EditorConfig.readConfiguration fsharpFile.FSharpFile
 
     config.MaxArrayOrListWidth == 123
+
+[<Test>]
+let ``record number_of_items parsing tests`` () =
+    let editorConfig = """
+[*.fs]
+fsharp_record_multiline_formatter = number_of_items
+fsharp_max_record_number_of_items = 4
+"""
+
+    use configFixture =
+        new ConfigurationFile(defaultConfig, content = editorConfig)
+
+    use fsharpFile = new FSharpFile()
+
+    let config =
+        EditorConfig.readConfiguration fsharpFile.FSharpFile
+
+    config.MaxRecordNumberOfItems == 4
+
+    config.RecordMultilineFormatter == NumberOfItems
+
+[<Test>]
+let ``record character_width parsing test with single option`` () =
+    let editorConfig = """
+[*.fs]
+fsharp_max_record_width = 123
+"""
+
+    use configFixture =
+        new ConfigurationFile(defaultConfig, content = editorConfig)
+
+    use fsharpFile = new FSharpFile()
+
+    let config =
+        EditorConfig.readConfiguration fsharpFile.FSharpFile
+
+    config.MaxRecordWidth == 123

src/Fantomas.Tests/NumberOfItemsTests.fs → src/Fantomas.Tests/NumberOfItemsListOrArrayTests.fs

@@ -1,4 +1,4 @@
-module Fantomas.Tests.NumberOfItemsTests
+module Fantomas.Tests.NumberOfItemsListOrArrayTests
 
 open NUnit.Framework
 open FsUnit
@@ -284,7 +284,7 @@ let ``long expressions with number of items set to 3 will get split due to max l
 """
 
 [<Test>]
-let ``character width with explicit width lists are formatted properly`` () =
+let ``character width with explicit width sized lists are formatted properly`` () =
     formatSourceString false """
 let x = [ a; b; c ]
 let y = [ longValueThatIsALotOfCharactersSoooooLong; longValueThatIsALotOfCharactersSoooooLong ]