findBreakingChanges: add check for removing repeatable from directive

Code is taken from #1541

Author: IvanGoncharov

src/utilities/__tests__/findBreakingChanges-test.js

@@ -645,6 +645,8 @@ describe('findBreakingChanges', () => {
 
       directive @NonNullDirectiveAdded on FIELD_DEFINITION
 
+      directive @DirectiveThatWasRepeatable repeatable on FIELD_DEFINITION
+
       directive @DirectiveName on FIELD_DEFINITION | QUERY
 
       type ArgThatChanges {
@@ -679,6 +681,8 @@ describe('findBreakingChanges', () => {
 
       directive @NonNullDirectiveAdded(arg1: Boolean!) on FIELD_DEFINITION
 
+      directive @DirectiveThatWasRepeatable on FIELD_DEFINITION
+
       directive @DirectiveName on FIELD_DEFINITION
 
       type ArgThatChanges {
@@ -761,6 +765,11 @@ describe('findBreakingChanges', () => {
         description:
           'A required arg arg1 on directive NonNullDirectiveAdded was added.',
       },
+      {
+        type: BreakingChangeType.DIRECTIVE_REPEATABLE_REMOVED,
+        description:
+          'Repeatable flag was removed from DirectiveThatWasRepeatable.',
+      },
       {
         type: BreakingChangeType.DIRECTIVE_LOCATION_REMOVED,
         description: 'QUERY was removed from DirectiveName.',
@@ -840,6 +849,23 @@ describe('findBreakingChanges', () => {
     ]);
   });
 
+  it('should detect removal of repeatable flag', () => {
+    const oldSchema = buildSchema(`
+      directive @DirectiveName repeatable on OBJECT
+    `);
+
+    const newSchema = buildSchema(`
+      directive @DirectiveName on OBJECT
+    `);
+
+    expect(findBreakingChanges(oldSchema, newSchema)).to.deep.equal([
+      {
+        type: BreakingChangeType.DIRECTIVE_REPEATABLE_REMOVED,
+        description: 'Repeatable flag was removed from DirectiveName.',
+      },
+    ]);
+  });
+
   it('should detect locations removed from a directive', () => {
     const oldSchema = buildSchema(`
       directive @DirectiveName on FIELD_DEFINITION | QUERY

src/utilities/findBreakingChanges.d.ts

@@ -20,6 +20,7 @@ type _BreakingChangeType = {
   DIRECTIVE_REMOVED: 'DIRECTIVE_REMOVED';
   DIRECTIVE_ARG_REMOVED: 'DIRECTIVE_ARG_REMOVED';
   REQUIRED_DIRECTIVE_ARG_ADDED: 'REQUIRED_DIRECTIVE_ARG_ADDED';
+  DIRECTIVE_REPEATABLE_REMOVED: 'DIRECTIVE_REPEATABLE_REMOVED';
   DIRECTIVE_LOCATION_REMOVED: 'DIRECTIVE_LOCATION_REMOVED';
 };
 

src/utilities/findBreakingChanges.js

@@ -51,6 +51,7 @@ export const BreakingChangeType = Object.freeze({
   DIRECTIVE_REMOVED: 'DIRECTIVE_REMOVED',
   DIRECTIVE_ARG_REMOVED: 'DIRECTIVE_ARG_REMOVED',
   REQUIRED_DIRECTIVE_ARG_ADDED: 'REQUIRED_DIRECTIVE_ARG_ADDED',
+  DIRECTIVE_REPEATABLE_REMOVED: 'DIRECTIVE_REPEATABLE_REMOVED',
   DIRECTIVE_LOCATION_REMOVED: 'DIRECTIVE_LOCATION_REMOVED',
 });
 
@@ -148,6 +149,13 @@ function findDirectiveChanges(
       });
     }
 
+    if (oldDirective.isRepeatable && !newDirective.isRepeatable) {
+      schemaChanges.push({
+        type: BreakingChangeType.DIRECTIVE_REPEATABLE_REMOVED,
+        description: `Repeatable flag was removed from ${oldDirective.name}.`,
+      });
+    }
+
     for (const location of oldDirective.locations) {
       if (newDirective.locations.indexOf(location) === -1) {
         schemaChanges.push({