Initial JSON parser and renderer. Not very pretty 😅

examples/Console/Json/Json.csproj

@@ -0,0 +1,15 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+ <PropertyGroup>
+ <OutputType>Exe</OutputType>
+ <TargetFramework>net7.0</TargetFramework>
+ <ExampleTitle>Json</ExampleTitle>
+ <ExampleDescription>Displays the capabilities of the current console.</ExampleDescription>
+ <ExampleGroup>Misc</ExampleGroup>
+ </PropertyGroup>
+
+ <ItemGroup>
+ <ProjectReference Include="..\..\Shared\Shared.csproj" />
+ </ItemGroup>
+
+</Project>

examples/Console/Json/Program.cs

@@ -0,0 +1,20 @@
+using Spectre.Console;
+
+namespace Info;
+
+public static class Program
+{
+ public static void Main()
+ {
+ var json = new JsonText("{ \"hello\": 32, \"World\": { \"foo\": 21, \"bar\": 255 } }");
+ AnsiConsole.Write(
+ new Panel(new Padder(json, new Padding(2, 1)))
+ {
+ Width = 35,
+ }
+ .Header("Some JSON in a panel")
+ .Collapse()
+ .RoundedBorder()
+ .BorderColor(Color.Yellow));
+ }
+}

examples/Examples.sln

@@ -79,6 +79,8 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Spectre.Console.Cli", "..\s
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Layout", "Console\Layout\Layout.csproj", "{A9FDE73A-8452-4CA3-B366-3F900597E132}"
 EndProject
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Json", "Console\Json\Json.csproj", "{ABE3E734-0756-4D5A-B28A-E6E526D9927D}"
+EndProject
 Global
  GlobalSection(SolutionConfigurationPlatforms) = preSolution
  Debug|Any CPU = Debug|Any CPU
@@ -521,6 +523,18 @@ Global
  {A9FDE73A-8452-4CA3-B366-3F900597E132}.Release|x64.Build.0 = Release|Any CPU
  {A9FDE73A-8452-4CA3-B366-3F900597E132}.Release|x86.ActiveCfg = Release|Any CPU
  {A9FDE73A-8452-4CA3-B366-3F900597E132}.Release|x86.Build.0 = Release|Any CPU
+ {ABE3E734-0756-4D5A-B28A-E6E526D9927D}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+ {ABE3E734-0756-4D5A-B28A-E6E526D9927D}.Debug|Any CPU.Build.0 = Debug|Any CPU
+ {ABE3E734-0756-4D5A-B28A-E6E526D9927D}.Debug|x64.ActiveCfg = Debug|Any CPU
+ {ABE3E734-0756-4D5A-B28A-E6E526D9927D}.Debug|x64.Build.0 = Debug|Any CPU
+ {ABE3E734-0756-4D5A-B28A-E6E526D9927D}.Debug|x86.ActiveCfg = Debug|Any CPU
+ {ABE3E734-0756-4D5A-B28A-E6E526D9927D}.Debug|x86.Build.0 = Debug|Any CPU
+ {ABE3E734-0756-4D5A-B28A-E6E526D9927D}.Release|Any CPU.ActiveCfg = Release|Any CPU
+ {ABE3E734-0756-4D5A-B28A-E6E526D9927D}.Release|Any CPU.Build.0 = Release|Any CPU
+ {ABE3E734-0756-4D5A-B28A-E6E526D9927D}.Release|x64.ActiveCfg = Release|Any CPU
+ {ABE3E734-0756-4D5A-B28A-E6E526D9927D}.Release|x64.Build.0 = Release|Any CPU
+ {ABE3E734-0756-4D5A-B28A-E6E526D9927D}.Release|x86.ActiveCfg = Release|Any CPU
+ {ABE3E734-0756-4D5A-B28A-E6E526D9927D}.Release|x86.Build.0 = Release|Any CPU
  EndGlobalSection
  GlobalSection(SolutionProperties) = preSolution
  HideSolutionNode = FALSE

src/Spectre.Console/Extensions/CharExtensions.cs

@@ -14,4 +14,14 @@ public static int GetCellWidth(this char character)
  {
  return Cell.GetCellLength(character);
  }
+
+ internal static bool IsDigit(this char character)
+ {
+ return character >= '0' && character <= '9';
+ }
+
+ internal static bool IsDigitLargerThanZero(this char character)
+ {
+ return character >= '1' && character <= '9';
+ }
 }

src/Spectre.Console/Internal/Text/StringBuffer.cs

@@ -23,11 +23,22 @@ public void Dispose()
  _reader.Dispose();
  }
 
+ public char Expect(char character)
+ {
+ var read = Read();
+ if (read != character)
+ {
+ throw new InvalidOperationException($"Expected '{character}', but found '{read}'");
+ }
+
+ return read;
+ }
+
  public char Peek()
  {
  if (Eof)
  {
- throw new InvalidOperationException("Tried to peek past the end of the text.");
+ return '\0';
  }
 
  return (char)_reader.Peek();
@@ -37,7 +48,7 @@ public char Read()
  {
  if (Eof)
  {
- throw new InvalidOperationException("Tried to read past the end of the text.");
+ return '\0';
  }
 
  Position++;

src/Spectre.Console/Widgets/Json/JsonParser.cs

@@ -0,0 +1,72 @@
+namespace Spectre.Console;
+
+internal static class JsonParser
+{
+ public static JsonSyntax Parse(List<JsonToken> tokens)
+ {
+ var reader = new JsonTokenReader(tokens);
+ return Parse(reader);
+ }
+
+ private static JsonSyntax Parse(JsonTokenReader reader)
+ {
+ var current = reader.Peek();
+ if (current?.Type != JsonTokenType.LeftBrace)
+ {
+ throw new InvalidOperationException("Invalid JSON");
+ }
+
+ return ParseObject(reader);
+ }
+
+ private static JsonSyntax ParseObject(JsonTokenReader reader)
+ {
+ reader.Consume(JsonTokenType.LeftBrace);
+
+ var result = new JsonObject();
+
+ if (reader.Peek()?.Type != JsonTokenType.RightBrace)
+ {
+ while (true)
+ {
+ var name = reader.Consume(JsonTokenType.String);
+ reader.Consume(JsonTokenType.Colon);
+ var value = ParseValue(reader);
+
+ result.Properties.Add(new JsonProperty(name.Lexeme, value));
+
+ if (reader.Peek()?.Type != JsonTokenType.Comma)
+ {
+ break;
+ }
+
+ reader.Consume(JsonTokenType.Comma);
+ }
+ }
+
+ reader.Consume(JsonTokenType.RightBrace);
+ return result;
+ }
+
+ private static JsonSyntax ParseValue(JsonTokenReader reader)
+ {
+ var current = reader.Peek();
+ if (current == null)
+ {
+ throw new InvalidOperationException("Could not parse value");
+ }
+
+ if (current.Type == JsonTokenType.LeftBrace)
+ {
+ return ParseObject(reader);
+ }
+
+ if (current.Type == JsonTokenType.Number)
+ {
+ reader.Consume(JsonTokenType.Number);
+ return new JsonNumber(current.Lexeme);
+ }
+
+ throw new InvalidOperationException("Unknown value token");
+ }
+}

src/Spectre.Console/Widgets/Json/JsonText.cs

@@ -0,0 +1,94 @@
+namespace Spectre.Console;
+
+public sealed class JsonText : JustInTimeRenderable
+{
+ private readonly JsonSyntax _syntax;
+
+ public JsonText(string json)
+ {
+ var tokens = JsonTokenizer.Tokenize(json);
+ _syntax = JsonParser.Parse(tokens);
+ }
+
+ protected override IRenderable Build()
+ {
+ var paragraph = new Paragraph();
+ _syntax.Accept(JsonParagraphCreator.Shared, new JsonContext(paragraph, new JsonTextStyles()));
+ return paragraph;
+ }
+
+ private sealed class JsonParagraphCreator : JsonSyntaxVisitor<JsonContext>
+ {
+ public static JsonParagraphCreator Shared { get; } = new JsonParagraphCreator();
+
+ public override void VisitNumber(JsonNumber syntax, JsonContext context)
+ {
+ context.Paragraph.Append(syntax.Lexeme, new Style(Color.Red));
+ }
+
+ public override void VisitObject(JsonObject syntax, JsonContext context)
+ {
+ context.Paragraph.Append("{");
+ context.Paragraph.Append("\n");
+ context.IncreaseIndentation();
+
+ foreach (var (_, _, last, property) in syntax.Properties.Enumerate())
+ {
+ context.InsertIndentation();
+ property.Accept(this, context);
+
+ if (!last)
+ {
+ context.Paragraph.Append(",", new Style(Color.Green));
+ }
+
+ context.Paragraph.Append("\n");
+ }
+
+ context.DecreaseIndentation();
+ context.InsertIndentation();
+ context.Paragraph.Append("}");
+ }
+
+ public override void VisitProperty(JsonProperty syntax, JsonContext context)
+ {
+ context.Paragraph.Append(syntax.Name, new Style(Color.Blue));
+ context.Paragraph.Append(":", new Style(Color.Yellow));
+ context.Paragraph.Append(" ");
+
+ syntax.Value.Accept(this, context);
+ }
+ }
+}
+
+internal sealed class JsonContext
+{
+ public Paragraph Paragraph { get; }
+ public int Indentation { get; private set; }
+ public JsonTextStyles Styling { get; }
+
+ public JsonContext(Paragraph paragraph, JsonTextStyles styling)
+ {
+ Paragraph = paragraph;
+ Styling = styling;
+ }
+
+ public void IncreaseIndentation()
+ {
+ Indentation++;
+ }
+
+ public void DecreaseIndentation()
+ {
+ Indentation = Math.Max(0, Indentation - 1);
+ }
+
+ public void InsertIndentation()
+ {
+ Paragraph.Append(new string(' ', Indentation * 3));
+ }
+}
+
+internal sealed class JsonTextStyles
+{
+}

src/Spectre.Console/Widgets/Json/JsonToken.cs

@@ -0,0 +1,13 @@
+namespace Spectre.Console;
+
+internal sealed class JsonToken
+{
+ public JsonTokenType Type { get; }
+ public string Lexeme { get; }
+
+ public JsonToken(JsonTokenType type, string lexeme)
+ {
+ Type = type;
+ Lexeme = lexeme ?? throw new ArgumentNullException(nameof(lexeme));
+ }
+}

src/Spectre.Console/Widgets/Json/JsonTokenReader.cs

@@ -0,0 +1,50 @@
+namespace Spectre.Console;
+
+internal sealed class JsonTokenReader
+{
+ private readonly List<JsonToken> _reader;
+ private readonly int _length;
+
+ public int Position { get; private set; }
+ public bool Eof => Position >= _length;
+
+ public JsonTokenReader(List<JsonToken> tokens)
+ {
+ _reader = tokens;
+ _length = tokens.Count;
+
+ Position = 0;
+ }
+
+ public JsonToken Consume(JsonTokenType type)
+ {
+ var read = Read();
+ if (read?.Type != type)
+ {
+ throw new InvalidOperationException($"Expected '{type}' token");
+ }
+
+ return read;
+ }
+
+ public JsonToken? Peek()
+ {
+ if (Eof)
+ {
+ return null;
+ }
+
+ return _reader[Position];
+ }
+
+ public JsonToken? Read()
+ {
+ if (Eof)
+ {
+ return null;
+ }
+
+ Position++;
+ return _reader[Position - 1];
+ }
+}

src/Spectre.Console/Widgets/Json/JsonTokenType.cs

@@ -0,0 +1,15 @@
+namespace Spectre.Console;
+
+internal enum JsonTokenType
+{
+ LeftBrace,
+ RightBrace,
+ LeftBracket,
+ RightBracket,
+ Colon,
+ Comma,
+ String,
+ Number,
+ Boolean,
+ Null,
+}