bugfix(graphql): Keep useful empty lines in description (#13013)

chimurai · fisker · web-flow · commit 794d9d15585e · 2022-06-16T13:33:09.000+08:00
Co-authored-by: fisker Cheung &lt;lionkay@gmail.com&gt;
diff --git a/changelog_unreleased/graphql/13013.md b/changelog_unreleased/graphql/13013.md
@@ -0,0 +1,34 @@
+#### Keep useful empty lines in description (#13013 by @chimurai)
+
+<!-- prettier-ignore -->
+```graphql
+# Input
+"""
+First line
+
+Second Line
+"""
+type Person {
+  name: String
+}
+
+# Prettier 2.7.0
+"""
+First line
+Second Line
+"""
+type Person {
+  name: String
+}
+
+
+# Prettier main
+"""
+First line
+
+Second Line
+"""
+type Person {
+  name: String
+}
+```
diff --git a/src/language-graphql/printer-graphql.js b/src/language-graphql/printer-graphql.js
@@ -130,10 +130,11 @@ function genericPrint(path, options, print) {
           lines[0] = lines[0].trim();
         }
 
-        return join(
-          hardline,
-          ['"""', ...(lines.length > 0 ? lines : []), '"""'].filter(Boolean)
-        );
+        if (lines.every((line) => line === "")) {
+          lines.length = 0;
+        }
+
+        return join(hardline, ['"""', ...lines, '"""']);
       }
       return [
         '"',
diff --git a/tests/format/graphql/string/__snapshots__/jsfmt.spec.js.snap b/tests/format/graphql/string/__snapshots__/jsfmt.spec.js.snap
@@ -32,6 +32,55 @@ type Person {name: String}
 """
 type Person {name: String}
 
+
+"""
+
+
+Empty lines before
+"""
+type Person {name: String}
+
+"""
+Empty lines after
+
+
+"""
+type Person {name: String}
+
+"""
+
+
+Empty lines around
+
+
+"""
+type Person {name: String}
+
+"""
+First line
+
+Second Line
+"""
+type Person {name: String}
+
+"""
+
+
+First line
+
+Second Line
+"""
+type Person {name: String}
+
+"""
+First line
+
+Second Line
+
+
+"""
+type Person {name: String}
+
 =====================================output=====================================
 """
 Customer
@@ -74,6 +123,54 @@ type Person {
   name: String
 }
 
+"""
+Empty lines before
+"""
+type Person {
+  name: String
+}
+
+"""
+Empty lines after
+"""
+type Person {
+  name: String
+}
+
+"""
+Empty lines around
+"""
+type Person {
+  name: String
+}
+
+"""
+First line
+
+Second Line
+"""
+type Person {
+  name: String
+}
+
+"""
+First line
+
+Second Line
+"""
+type Person {
+  name: String
+}
+
+"""
+First line
+
+Second Line
+"""
+type Person {
+  name: String
+}
+
 ================================================================================
 `;
 
diff --git a/tests/format/graphql/string/description.graphql b/tests/format/graphql/string/description.graphql
@@ -23,3 +23,52 @@ type Person {name: String}
   2
 """
 type Person {name: String}
+
+
+"""
+
+
+Empty lines before
+"""
+type Person {name: String}
+
+"""
+Empty lines after
+
+
+"""
+type Person {name: String}
+
+"""
+
+
+Empty lines around
+
+
+"""
+type Person {name: String}
+
+"""
+First line
+
+Second Line
+"""
+type Person {name: String}
+
+"""
+
+
+First line
+
+Second Line
+"""
+type Person {name: String}
+
+"""
+First line
+
+Second Line
+
+
+"""
+type Person {name: String}
