Re-add support for line endings being configurable. (#960)

* Re-add support for line endings being configurable.

closes #935

* Format file

* Update Src/CSharpier.Cli/Options/CaseInsensitiveEnumConverter.cs

Co-authored-by: Lasath Fernando <devel@lasath.org>

---------

Co-authored-by: Lasath Fernando <devel@lasath.org>

Docs/Configuration.md

@@ -5,6 +5,7 @@ hide_table_of_contents: true
 CSharpier has support for a configuration file. You can use any of the following files
 - A ```.csharpierrc``` file in JSON or YAML.
 - A ```.csharpierrc.json``` or ```.csharpierrc.yaml``` file.
+- A ```.editorconfig``` file. See EditorConfig section below.
 
 The configuration file will be resolved starting from the location of the file being formatted, and searching up the file tree until a config file is (or isn’t) found.
 
@@ -14,35 +15,49 @@ JSON
 {
     "printWidth": 100,
     "useTabs": false,
-    "tabWidth": 4
+    "tabWidth": 4,
+    "endOfLine": "auto"
 }
 ```
 YAML
 ```yaml
 printWidth: 100
 useTabs: false
 tabWidth: 4
+endOfLine: auto
 ```
 
 #### Print Width
 Specify at what point the printer will wrap content. This is not a hard limit. Some lines will be shorter or longer.
 
-Default 100
+Default `100`
 #### Use Tabs
 _First available in 0.17.0_
 
 Indent lines with tabs instead of spaces.
 
-Default false
+Default `false`
 #### Tab Width
 _First available in 0.17.0_
 
 Specify the number of spaces used per indentation level.
 
-Default 4
+Default `4`
+
+#### End of Line
+_First available in 0.26.0_
+
+Valid options:
+
+- "auto" - Maintain existing line endings (mixed values within one file are normalised by looking at what's used after the first line)
+- "lf" – Line Feed only (\n), common on Linux and macOS as well as inside git repos
+- "crlf" - Carriage Return + Line Feed characters (\r\n), common on Windows
+
+Default `auto`
+
 
 #### Preprocessor Symbol Sets
-**Removed in 0.25.0**
+_Removed in 0.25.0_
 
 Currently CSharpier only has basic support for understanding how to format code inside of `#if` directives.
 It will attempt to determine which sets of preprocessor symbols are needed for roslyn to parse all the code in each file.
@@ -62,3 +77,22 @@ For example in the following code block, the following symbol sets would be need
 When supplying symbol sets, they will be used for all files being formatted. This will slow down formatting, and determining all symbol sets needed across all files won't be straight forward.
 
 The long term plan is to improve Csharpier's ability to determine the symbol sets itself and to allow specifying them for individual files.
+
+### EditorConfig
+
+CSharpier supports configuration via an `.editorconfig` file. A `.csahrpierrc*` file in the same directory will take priority.
+
+```ini
+[*]
+# Non-configurable behaviors
+charset = utf-8
+insert_final_newline = true
+trim_trailing_whitespace = true
+
+# Configurable behaviors
+# end_of_line = lf - there is no 'auto' with a .editorconfig
+indent_style = space
+indent_size = 4
+max_line_length = 100
+
+```

Src/CSharpier.Cli/EditorConfig/EditorConfigSections.cs

@@ -34,6 +34,11 @@ public PrinterOptions ConvertToPrinterOptions(string filePath)
             printerOptions.TabWidth = resolvedConfiguration.IndentSize ?? printerOptions.TabWidth;
         }
 
+        if (resolvedConfiguration.EndOfLine is { } endOfLine)
+        {
+            printerOptions.EndOfLine = endOfLine;
+        }
+
         return printerOptions;
     }
 
@@ -43,6 +48,7 @@ private class ResolvedConfiguration
         public int? IndentSize { get; }
         public int? TabWidth { get; }
         public int? MaxLineLength { get; }
+        public EndOfLine? EndOfLine { get; }
 
         public ResolvedConfiguration(List<Section> sections)
         {
@@ -81,6 +87,12 @@ public ResolvedConfiguration(List<Section> sections)
                     ? tabWidthValue
                     : this.IndentSize;
             }
+
+            var endOfLine = sections.LastOrDefault(o => o.EndOfLine != null)?.EndOfLine;
+            if (Enum.TryParse(endOfLine, true, out EndOfLine result))
+            {
+                this.EndOfLine = result;
+            }
         }
     }
 }

Src/CSharpier.Cli/EditorConfig/Section.cs

@@ -11,6 +11,7 @@ public class Section
     public string? IndentSize { get; }
     public string? TabWidth { get; }
     public string? MaxLineLength { get; }
+    public string? EndOfLine { get; }
 
     public Section(SectionData section, string directory)
     {
@@ -20,6 +21,7 @@ public Section(SectionData section, string directory)
         this.IndentSize = section.Keys["indent_size"];
         this.TabWidth = section.Keys["tab_width"];
         this.MaxLineLength = section.Keys["max_line_length"];
+        this.EndOfLine = section.Keys["end_of_line"];
     }
 
     public bool IsMatch(string fileName)

Src/CSharpier.Cli/Options/CaseInsensitiveEnumConverter.cs

@@ -0,0 +1,36 @@
+namespace CSharpier.Cli.Options;
+
+using System.Text.Json;
+using System.Text.Json.Serialization;
+
+internal class CaseInsensitiveEnumConverter<TEnum> : JsonConverter<TEnum>
+    where TEnum : struct
+{
+    public override TEnum Read(
+        ref Utf8JsonReader reader,
+        Type typeToConvert,
+        JsonSerializerOptions options
+    )
+    {
+        if (reader.TokenType != JsonTokenType.String)
+        {
+            throw new JsonException(
+                $"Expected a string for enum parsing, but got {reader.TokenType}."
+            );
+        }
+
+        var enumText = reader.GetString();
+        if (Enum.TryParse(enumText, ignoreCase: true, out TEnum result))
+        {
+            return result;
+        }
+
+        throw new JsonException($"Unable to parse '{enumText}' to enum of type {typeof(TEnum)}.");
+    }
+
+    public override void Write(Utf8JsonWriter writer, TEnum value, JsonSerializerOptions options)
+    {
+        var enumText = value.ToString();
+        writer.WriteStringValue(enumText);
+    }
+}

Src/CSharpier.Cli/Options/ConfigurationFileOptions.cs

@@ -2,16 +2,20 @@ namespace CSharpier.Cli.Options;
 
 using System.IO.Abstractions;
 using System.Text.Json;
+using System.Text.Json.Serialization;
 using Microsoft.Extensions.Logging;
 using YamlDotNet.Serialization;
 using YamlDotNet.Serialization.NamingConventions;
 
-public class ConfigurationFileOptions
+internal class ConfigurationFileOptions
 {
     public int PrintWidth { get; init; } = 100;
     public int TabWidth { get; init; } = 4;
     public bool UseTabs { get; init; }
 
+    [JsonConverter(typeof(CaseInsensitiveEnumConverter<EndOfLine>))]
+    public EndOfLine EndOfLine { get; init; }
+
     private static readonly string[] validExtensions = { ".csharpierrc", ".json", ".yml", ".yaml" };
 
     internal static PrinterOptions CreatePrinterOptionsFromPath(
@@ -34,7 +38,7 @@ ConfigurationFileOptions configurationFileOptions
             TabWidth = configurationFileOptions.TabWidth,
             UseTabs = configurationFileOptions.UseTabs,
             Width = configurationFileOptions.PrintWidth,
-            EndOfLine = EndOfLine.Auto
+            EndOfLine = configurationFileOptions.EndOfLine
         };
     }
 

Src/CSharpier.Tests/OptionsProviderTests.cs

@@ -50,13 +50,14 @@ public async Task Should_Return_Json_Extension_Options()
             "c:/test/.csharpierrc.json",
             @"{ 
     ""printWidth"": 10, 
-    ""preprocessorSymbolSets"": [""1,2"", ""3""]
+    ""endOfLine"": ""crlf""
 }"
         );
 
         var result = await context.CreateProviderAndGetOptionsFor("c:/test", "c:/test/test.cs");
 
         result.Width.Should().Be(10);
+        result.EndOfLine.Should().Be(EndOfLine.CRLF);
     }
 
     [TestCase("yaml")]
@@ -68,15 +69,14 @@ public async Task Should_Return_Yaml_Extension_Options(string extension)
             $"c:/test/.csharpierrc.{extension}",
             @"
 printWidth: 10
-preprocessorSymbolSets: 
-  - 1,2
-  - 3
+endOfLine: crlf
 "
         );
 
         var result = await context.CreateProviderAndGetOptionsFor("c:/test", "c:/test/test.cs");
 
         result.Width.Should().Be(10);
+        result.EndOfLine.Should().Be(EndOfLine.CRLF);
     }
 
     [TestCase("{ \"printWidth\": 10 }")]
@@ -203,6 +203,7 @@ public async Task Should_Support_EditorConfig_Basic()
 indent_style = space
 indent_size = 2
 max_line_length = 10
+end_of_line = crlf
 "
         );
 
@@ -211,6 +212,7 @@ public async Task Should_Support_EditorConfig_Basic()
         result.UseTabs.Should().BeFalse();
         result.TabWidth.Should().Be(2);
         result.Width.Should().Be(10);
+        result.EndOfLine.Should().Be(EndOfLine.CRLF);
     }
 
     [TestCase("tab_width")]
@@ -459,6 +461,7 @@ private static void ShouldHaveDefaultOptions(PrinterOptions printerOptions)
         printerOptions.Width.Should().Be(100);
         printerOptions.TabWidth.Should().Be(4);
         printerOptions.UseTabs.Should().BeFalse();
+        printerOptions.EndOfLine.Should().Be(EndOfLine.Auto);
     }
 
     private class TestContext

Src/CSharpier/PrinterOptions.cs

@@ -7,7 +7,7 @@ internal class PrinterOptions
     public bool UseTabs { get; set; }
     public int TabWidth { get; set; } = 4;
     public int Width { get; set; } = 100;
-    public EndOfLine EndOfLine { get; init; } = EndOfLine.Auto;
+    public EndOfLine EndOfLine { get; set; } = EndOfLine.Auto;
     public bool TrimInitialLines { get; init; } = true;
 
     public const int WidthUsedByTests = 100;