From 570c3180b95801fdd43d0730d5825c1facec817f Mon Sep 17 00:00:00 2001
From: Trevor Scheer <trevor.scheer@gmail.com>
Date: Sat, 26 Mar 2022 08:59:04 -0700
Subject: [PATCH] [graphql] Add support for printing `SchemaExtension` nodes
 (#12519)

* Add support for printing SchemaExtension nodes

* Add changelog entry

* Lint

* Update 12519.md

Co-authored-by: fisker Cheung <lionkay@gmail.com>
---
 changelog_unreleased/graphql/12519.md         | 17 ++++++++++++++
 src/language-graphql/printer-graphql.js       | 23 +++++++++++++++++++
 .../__snapshots__/jsfmt.spec.js.snap          |  8 +++++++
 .../kitchen-sink/schema_kitchen_sink.graphql  |  4 ++++
 .../schema/__snapshots__/jsfmt.spec.js.snap   | 15 ++++++++++++
 tests/format/graphql/schema/schema.graphql    |  7 ++++++
 6 files changed, 74 insertions(+)
 create mode 100644 changelog_unreleased/graphql/12519.md

diff --git a/changelog_unreleased/graphql/12519.md b/changelog_unreleased/graphql/12519.md
new file mode 100644
index 000000000..16e13ba3f
--- /dev/null
+++ b/changelog_unreleased/graphql/12519.md
@@ -0,0 +1,17 @@
+#### Add support for printing SchemaExtension nodes (#12519 by @trevor-scheer)
+
+<!-- prettier-ignore -->
+```graphql
+# Input
+extend schema { subscription: Subscription }
+extend schema @directive
+
+# Prettier stable
+N/A - throws error
+
+# Prettier main
+extend schema {
+  subscription: Subscription
+}
+extend schema @directive
+```
diff --git a/src/language-graphql/printer-graphql.js b/src/language-graphql/printer-graphql.js
index 883927577..a2043a5bc 100644
--- a/src/language-graphql/printer-graphql.js
+++ b/src/language-graphql/printer-graphql.js
@@ -402,6 +402,29 @@ function genericPrint(path, options, print) {
       ];
     }
 
+    case "SchemaExtension": {
+      return [
+        "extend schema",
+        printDirectives(path, print, node),
+        ...(node.operationTypes.length > 0
+          ? [
+              " {",
+              indent([
+                hardline,
+                join(
+                  hardline,
+                  path.call(
+                    (opsPath) => printSequence(opsPath, options, print),
+                    "operationTypes"
+                  )
+                ),
+              ]),
+              hardline,
+              "}",
+            ]
+          : []),
+      ];
+    }
     case "SchemaDefinition": {
       return [
         print("description"),
diff --git a/tests/format/graphql/kitchen-sink/__snapshots__/jsfmt.spec.js.snap b/tests/format/graphql/kitchen-sink/__snapshots__/jsfmt.spec.js.snap
index c930d15b2..bc9c3d3e3 100644
--- a/tests/format/graphql/kitchen-sink/__snapshots__/jsfmt.spec.js.snap
+++ b/tests/format/graphql/kitchen-sink/__snapshots__/jsfmt.spec.js.snap
@@ -149,6 +149,10 @@ schema {
   mutation: MutationType
 }
 
+extend schema @directive {
+  subscription: Subscription
+}
+
 """
 This is a description
 of the \`Foo\` type.
@@ -271,6 +275,10 @@ schema {
   mutation: MutationType
 }
 
+extend schema @directive {
+  subscription: Subscription
+}
+
 """
 This is a description
 of the \`Foo\` type.
diff --git a/tests/format/graphql/kitchen-sink/schema_kitchen_sink.graphql b/tests/format/graphql/kitchen-sink/schema_kitchen_sink.graphql
index 0c72dcca2..e4a5327bf 100644
--- a/tests/format/graphql/kitchen-sink/schema_kitchen_sink.graphql
+++ b/tests/format/graphql/kitchen-sink/schema_kitchen_sink.graphql
@@ -8,6 +8,10 @@ schema {
   mutation: MutationType
 }
 
+extend schema @directive {
+  subscription: Subscription
+}
+
 """
 This is a description
 of the `Foo` type.
diff --git a/tests/format/graphql/schema/__snapshots__/jsfmt.spec.js.snap b/tests/format/graphql/schema/__snapshots__/jsfmt.spec.js.snap
index 250af029e..280b7dafd 100644
--- a/tests/format/graphql/schema/__snapshots__/jsfmt.spec.js.snap
+++ b/tests/format/graphql/schema/__snapshots__/jsfmt.spec.js.snap
@@ -13,6 +13,13 @@ schema {
   subscription: Subscription
 }
 
+extend schema { subscription: Subscription }
+
+# \`SchemaExtension\`s don't require any operation types and doesn't print
+# curlies in their abscence.
+extend schema
+  @directive
+
 =====================================output=====================================
 """
 Schema definition description
@@ -23,5 +30,13 @@ schema {
   subscription: Subscription
 }
 
+extend schema {
+  subscription: Subscription
+}
+
+# \`SchemaExtension\`s don't require any operation types and doesn't print
+# curlies in their abscence.
+extend schema @directive
+
 ================================================================================
 `;
diff --git a/tests/format/graphql/schema/schema.graphql b/tests/format/graphql/schema/schema.graphql
index 4ffc3dcfe..f426bfad4 100644
--- a/tests/format/graphql/schema/schema.graphql
+++ b/tests/format/graphql/schema/schema.graphql
@@ -4,3 +4,10 @@ schema {
   mutation: Mutation
   subscription: Subscription
 }
+
+extend schema { subscription: Subscription }
+
+# `SchemaExtension`s don't require any operation types and doesn't print
+# curlies in their abscence.
+extend schema
+  @directive