Add better schema formatting options

src/HotChocolate/Fusion/src/Fusion.Execution.Types/Serialization/SchemaFormatter.cs

@@ -12,7 +12,7 @@ public static class SchemaFormatter
         new()
         {
             Indented = true,
-            MaxDirectivesPerLine = 0
+            PrintWidth = 80
         };
 
     public static string FormatAsString(

src/HotChocolate/Fusion/src/Fusion.Language/ISyntaxWriter.cs

@@ -5,6 +5,11 @@ namespace HotChocolate.Fusion.Language;
 /// </summary>
 internal interface ISyntaxWriter
 {
+    /// <summary>
+    /// Gets the current column position in the output.
+    /// </summary>
+    int Column { get; }
+
     /// <summary>
     /// Increase writer indentation.
     /// </summary>

src/HotChocolate/Fusion/src/Fusion.Language/StringSyntaxWriter.cs

@@ -8,8 +8,12 @@ internal class StringSyntaxWriter(StringSyntaxWriterOptions? options = null) : I
         ?? new StringSyntaxWriterOptions();
 
     private int _indent;
+    private int _column;
     private readonly StringBuilder _stringBuilder = new();
 
+    /// <inheritdoc />
+    public int Column => _column;
+
     public void Indent()
     {
         _indent++;
@@ -26,18 +30,40 @@ public void Unindent()
     public void Write(char c)
     {
         _stringBuilder.Append(c);
+
+        if (c == '\n')
+        {
+            _column = 0;
+        }
+        else
+        {
+            _column++;
+        }
     }
 
     public void Write(string s)
     {
         _stringBuilder.Append(s);
+
+        var lastNewLine = s.LastIndexOf('\n');
+
+        if (lastNewLine >= 0)
+        {
+            _column = s.Length - lastNewLine - 1;
+        }
+        else
+        {
+            _column += s.Length;
+        }
     }
 
     public void WriteIndent(bool condition = true)
     {
         if (condition && _indent > 0)
         {
-            _stringBuilder.Append(' ', _options.IndentSize * _indent);
+            var spaces = _options.IndentSize * _indent;
+            _stringBuilder.Append(' ', spaces);
+            _column += spaces;
         }
     }
 
@@ -46,6 +72,7 @@ public void WriteLine(bool condition = true)
         if (condition)
         {
             _stringBuilder.Append(_options.NewLine);
+            _column = 0;
         }
     }
 
@@ -54,12 +81,14 @@ public void WriteSpace(bool condition = true)
         if (condition)
         {
             _stringBuilder.Append(' ');
+            _column++;
         }
     }
 
     public void Clear()
     {
         _stringBuilder.Clear();
+        _column = 0;
     }
 
     public override string ToString()

src/HotChocolate/Fusion/test/Fusion.Composition.ApolloFederation.Tests/__snapshots__/FederationSchemaTransformerTests.Transform_CompositeKey.md

@@ -0,0 +1,46 @@
+# Transform_CompositeKey
+
+## Apollo Federation SDL
+
+```graphql
+schema @link(url: "https://specs.apollo.dev/federation/v2.6", import: ["@key"]) {
+  query: Query
+}
+type Product @key(fields: "sku package") {
+  sku: String!
+  package: String!
+  name: String
+}
+type Query {
+  products: [Product]
+  _service: _Service!
+  _entities(representations: [_Any!]!): [_Entity]!
+}
+type _Service { sdl: String! }
+union _Entity = Product
+scalar FieldSet
+scalar _Any
+directive @key(fields: FieldSet! resolvable: Boolean = true) repeatable on OBJECT | INTERFACE
+directive @link(url: String! import: [String!]) repeatable on SCHEMA
+```
+
+## Transformed SDL
+
+```graphql
+schema {
+  query: Query
+}
+
+type Query {
+  productBySkuAndPackage(package: String!, sku: String!): Product
+    @internal
+    @lookup
+  products: [Product]
+}
+
+type Product @key(fields: "sku package") {
+  name: String
+  package: String!
+  sku: String!
+}
+```

src/HotChocolate/Fusion/test/Fusion.Composition.ApolloFederation.Tests/__snapshots__/FederationSchemaTransformerTests.Transform_ExternalDirective.md

@@ -0,0 +1,42 @@
+# Transform_ExternalDirective
+
+## Apollo Federation SDL
+
+```graphql
+schema @link(url: "https://specs.apollo.dev/federation/v2.6", import: ["@key", "@external"]) {
+  query: Query
+}
+type Product @key(fields: "id") {
+  id: ID!
+  price: Float @external
+}
+type Query {
+  products: [Product]
+  _service: _Service!
+  _entities(representations: [_Any!]!): [_Entity]!
+}
+type _Service { sdl: String! }
+union _Entity = Product
+scalar FieldSet
+scalar _Any
+directive @key(fields: FieldSet! resolvable: Boolean = true) repeatable on OBJECT | INTERFACE
+directive @external on FIELD_DEFINITION
+directive @link(url: String! import: [String!]) repeatable on SCHEMA
+```
+
+## Transformed SDL
+
+```graphql
+schema {
+  query: Query
+}
+
+type Query {
+  productById(id: ID!): Product @internal @lookup
+  products: [Product]
+}
+
+type Product @key(fields: "id") {
+  id: ID!
+}
+```

src/HotChocolate/Fusion/test/Fusion.Composition.ApolloFederation.Tests/__snapshots__/FederationSchemaTransformerTests.Transform_FullIntegration.md

@@ -0,0 +1,82 @@
+# Transform_FullIntegration
+
+## Apollo Federation SDL
+
+```graphql
+schema @link(url: "https://specs.apollo.dev/federation/v2.6", import: ["@key", "@requires", "@provides", "@external"]) {
+  query: Query
+}
+type Product @key(fields: "id") @key(fields: "sku package") {
+  id: ID!
+  sku: String!
+  package: String!
+  name: String
+  price: Float
+  weight: Float
+  inStock: Boolean
+  createdBy: User @provides(fields: "totalProductsCreated")
+}
+type User @key(fields: "id") {
+  id: ID!
+  username: String @external
+  totalProductsCreated: Int
+}
+type Review {
+  body: String
+  author: User
+}
+type Query {
+  product(id: ID!): Product
+  reviews: [Review]
+  _service: _Service!
+  _entities(representations: [_Any!]!): [_Entity]!
+}
+type _Service { sdl: String! }
+union _Entity = Product | User
+scalar FieldSet
+scalar _Any
+directive @key(fields: FieldSet! resolvable: Boolean = true) repeatable on OBJECT | INTERFACE
+directive @requires(fields: FieldSet!) on FIELD_DEFINITION
+directive @provides(fields: FieldSet!) on FIELD_DEFINITION
+directive @external on FIELD_DEFINITION
+directive @link(url: String! import: [String!]) repeatable on SCHEMA
+```
+
+## Transformed SDL
+
+```graphql
+schema {
+  query: Query
+}
+
+type Query {
+  product(id: ID!): Product
+  productById(id: ID!): Product @internal @lookup
+  productBySkuAndPackage(package: String!, sku: String!): Product
+    @internal
+    @lookup
+  reviews: [Review]
+  userById(id: ID!): User @internal @lookup
+}
+
+type Product @key(fields: "id") @key(fields: "sku package") {
+  createdBy: User @provides(fields: "totalProductsCreated")
+  id: ID!
+  inStock: Boolean
+  name: String
+  package: String!
+  price: Float
+  sku: String!
+  weight: Float
+}
+
+type Review {
+  author: User
+  body: String
+}
+
+type User @key(fields: "id") {
+  id: ID!
+  totalProductsCreated: Int
+}
+```

src/HotChocolate/Fusion/test/Fusion.Composition.ApolloFederation.Tests/__snapshots__/FederationSchemaTransformerTests.Transform_KeyResolvableArgument.md

@@ -0,0 +1,42 @@
+# Transform_KeyResolvableArgument
+
+## Apollo Federation SDL
+
+```graphql
+schema @link(url: "https://specs.apollo.dev/federation/v2.6", import: ["@key"]) {
+  query: Query
+}
+type Product @key(fields: "id", resolvable: true) {
+  id: ID!
+  name: String
+}
+type Query {
+  products: [Product]
+  _service: _Service!
+  _entities(representations: [_Any!]!): [_Entity]!
+}
+type _Service { sdl: String! }
+union _Entity = Product
+scalar FieldSet
+scalar _Any
+directive @key(fields: FieldSet! resolvable: Boolean = true) repeatable on OBJECT | INTERFACE
+directive @link(url: String! import: [String!]) repeatable on SCHEMA
+```
+
+## Transformed SDL
+
+```graphql
+schema {
+  query: Query
+}
+
+type Query {
+  productById(id: ID!): Product @internal @lookup
+  products: [Product]
+}
+
+type Product @key(fields: "id") {
+  id: ID!
+  name: String
+}
+```

src/HotChocolate/Fusion/test/Fusion.Composition.ApolloFederation.Tests/__snapshots__/FederationSchemaTransformerTests.Transform_MultipleKeys.md

@@ -0,0 +1,49 @@
+# Transform_MultipleKeys
+
+## Apollo Federation SDL
+
+```graphql
+schema @link(url: "https://specs.apollo.dev/federation/v2.6", import: ["@key"]) {
+  query: Query
+}
+type Product @key(fields: "id") @key(fields: "sku package") {
+  id: ID!
+  sku: String!
+  package: String!
+  name: String
+}
+type Query {
+  products: [Product]
+  _service: _Service!
+  _entities(representations: [_Any!]!): [_Entity]!
+}
+type _Service { sdl: String! }
+union _Entity = Product
+scalar FieldSet
+scalar _Any
+directive @key(fields: FieldSet! resolvable: Boolean = true) repeatable on OBJECT | INTERFACE
+directive @link(url: String! import: [String!]) repeatable on SCHEMA
+```
+
+## Transformed SDL
+
+```graphql
+schema {
+  query: Query
+}
+
+type Query {
+  productById(id: ID!): Product @internal @lookup
+  productBySkuAndPackage(package: String!, sku: String!): Product
+    @internal
+    @lookup
+  products: [Product]
+}
+
+type Product @key(fields: "id") @key(fields: "sku package") {
+  id: ID!
+  name: String
+  package: String!
+  sku: String!
+}
+```