New @graphql-inspector/compare-changes package for comparing diff changes (#2939)

Author: jdolle

.changeset/@graphql-inspector_action-2939-dependencies.md

@@ -0,0 +1,6 @@
+---
+'@graphql-inspector/action': patch
+---
+dependencies updates:
+  - Updated dependency [`js-yaml@4.1.1` ↗︎](https://www.npmjs.com/package/js-yaml/v/4.1.1) (from
+    `4.1.0`, in `dependencies`)

.changeset/giant-bulldogs-film.md

@@ -0,0 +1,6 @@
+---
+'@graphql-inspector/compare-changes': minor
+---
+
+Initial release. Exposes a utility function for checking equivalency of changes output from the
+"@graphql-inspector/core" diff function.

packages/compare-changes/CHANGELOG.md

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+# GraphQL Change Comparison Utility
+
+This package allows comparing two changes (output from `@graphql-inspector/core`'s `diff`) for determining if they would result in the same output.
+
+## Usage
+
+```typescript
+import { buildSchema } from 'graphql';
+import { diff } from '@graphql-inspector/diff';
+import { isChangeEqual } from '@graphql-inspector/compare-changes';
+
+const before = buildSchema(/* existing SDL */);
+const after = buildSchema(/* new SDL */);
+const changes = diff(before, after);
+
+const hasChange = changes.some((c) => isChangeEqual(c, existingChange));
+```