🦺 Parse tree

Author: aexol

src/TreeOperations/merge.ts

@@ -32,7 +32,9 @@ export const mergeTrees = (tree1: ParserTree, tree2: ParserTree) => {
   const errors: Array<{ conflictingNode: string; conflictingField: string }> = [];
   // merge nodes
   tree1.nodes.forEach((t1n) => {
-    const matchingNode = tree2.nodes.find((t2n) => t2n.name === t1n.name && t1n.data.type === t2n.data.type);
+    const matchingNode = tree2.nodes
+      .filter((t) => t.data.type !== TypeSystemDefinition.SchemaDefinition)
+      .find((t2n) => t2n.name === t1n.name && t1n.data.type === t2n.data.type);
     if (matchingNode) {
       if (isExtensionNode(matchingNode.data.type)) {
         t1n.args.forEach((t1nA) => {

src/__tests__/TreeOperations/merge.spec.ts

@@ -189,4 +189,44 @@ describe('Merging GraphQL Schemas', () => {
       `,
     );
   });
+  it('Should merge schemas but maintain original schema node', () => {
+    const baseSchema = `
+    type DDD{
+        firstName: String
+        health: String
+    }
+    schema{
+        query: DDD
+    }
+    `;
+
+    const mergingSchema = `
+    type Query{
+        lastName: String
+    }
+    type Mutation{
+        ddd: String
+    }
+    `;
+    const t1 = mergeSDLs(baseSchema, mergingSchema);
+    if (t1.__typename === 'error') throw new Error('Invalid parse');
+    expectTrimmedEqual(
+      t1.sdl,
+      `
+      type DDD{
+          firstName: String
+          health: String
+      }
+      schema{
+          query: DDD
+      }
+      type Query{
+        lastName: String
+    }
+    type Mutation{
+        ddd: String
+    }
+      `,
+    );
+  });
 });