Fix PullMerge() failure

common/changes/@itwin/core-backend/affank-fix-pullmerge_2025-06-27-11-56.json

@@ -0,0 +1,10 @@
+{
+  "changes": [
+    {
+      "packageName": "@itwin/core-backend",
+      "comment": "Fix issue related to pullMerge() failure",
+      "type": "none"
+    }
+  ],
+  "packageName": "@itwin/core-backend"
+}

core/backend/src/SqliteChangesetReader.ts

@@ -10,6 +10,9 @@ import { ECDb } from "./ECDb";
 import { IModelDb } from "./IModelDb";
 import { IModelNative } from "./internal/NativePlatform";
 import { _nativeDb } from "./internal/Symbols";
+import * as fs from "fs";
+import { EOL } from "os";
+import { createHash } from "crypto";
 
 /** Changed value type
  * @beta
@@ -417,4 +420,89 @@ export class SqliteChangesetReader implements Disposable {
   public [Symbol.dispose](): void {
     this.close();
   }
+
+  /**
+   * Export changeset as JSON file.
+   * @param fileName name of the file to which changeset will be exported.
+   * @param options options for export
+   * @param options.excludeFilter function to filter out changes that should not be exported.
+   * @param options.replaceBlobWithHash if true then binary values will be replaced with sha1 hash of the value.
+   * @param options.indent if true then output will be indented.
+   * @note This function will write to file in current working directory.
+   * @beta
+   */
+  public exportAsJson(
+    fileName: string,
+    options?: {
+      readonly excludeFilter?: (tableName: string, op: SqliteChangeOp, isIndirect: boolean) => boolean,
+      readonly replaceBlobWithHash?: true,
+      readonly indent?: true }): void {
+    const replaceUint8ArrayWithSha1 = (val: unknown) => {
+      if (options?.replaceBlobWithHash && val instanceof Uint8Array) {
+        const hash = createHash("sha1");
+        hash.update(val);
+        return hash.digest("hex");
+      }
+      return val;
+    };
+
+    const indentText = (text: string, indentSize: number) => {
+      const lines = text.split(/\r?\n/);
+      const prefix = "".padEnd(indentSize, " ");
+      let out = "";
+      lines.forEach((line) => {
+        out += `${prefix}${line}${EOL}`;
+      });
+      return out;
+    }
+
+    const stream = fs.createWriteStream(fileName, { flags: "w+" });
+    stream.on('error', (err) => {
+      console.error(`Failed to write to file ${fileName}:`, err);
+      stream.end(); // Ensure the stream is closed on error
+      throw err; // Rethrow the error to notify the caller
+    });
+    stream.write("[");
+    stream.write(EOL);
+    let nChange = 0;
+    while (this.step()) {
+      if (options?.excludeFilter && options.excludeFilter(this.tableName, this.op, this.isIndirect)) {
+        continue;
+      }
+      const values = [];
+      for (let i = 0; i < this.columnCount; ++i) {
+        const newValue = this.op === "Inserted" || this.op === "Updated" ?
+          replaceUint8ArrayWithSha1(this.getChangeValue(i, "New")) : undefined;
+        const oldValue = this.op === "Deleted" || this.op === "Updated" ?
+          replaceUint8ArrayWithSha1(this.getChangeValue(i, "Old")) : undefined;
+
+        values.push({
+          newValue,
+          oldValue,
+        });
+      }
+      const row = {
+        table: this.tableName,
+        op: this.op,
+        indirect: this.isIndirect,
+        values,
+      };
+
+      if (nChange > 0) {
+        stream.write("  ,");
+        stream.write(EOL);
+      }
+
+      if (options?.indent) {
+        stream.write(indentText(JSON.stringify(row, undefined, 2), 2));
+      } else {
+        stream.write(JSON.stringify(row));
+      }
+
+      nChange++;
+    }
+    stream.write("]");
+    stream.write(EOL);
+    stream.end();
+  }
 }

core/backend/src/test/standalone/ApplyChangeset.test.ts

@@ -0,0 +1,54 @@
+/*---------------------------------------------------------------------------------------------
+* Copyright (c) Bentley Systems, Incorporated. All rights reserved.
+* See LICENSE.md in the project root for license terms and full copyright notice.
+*--------------------------------------------------------------------------------------------*/
+
+import * as chai from "chai";
+import * as chaiAsPromised from "chai-as-promised";
+import { HubWrappers, KnownTestLocations } from "..";
+import { ChannelControl, IModelHost } from "../../core-backend";
+import { HubMock } from "../../internal/HubMock";
+import { Suite } from "mocha";
+chai.use(chaiAsPromised);
+
+describe("apply changesets", function (this: Suite) {
+  before(async () => {
+    await IModelHost.startup();
+  });
+  it("Apply changeset with no local changes, should not create new local changes", async () => {
+    HubMock.startup("PullMergeMethod", KnownTestLocations.outputDir);
+
+    const iModelId = await HubMock.createNewIModel({ accessToken: "user1", iTwinId: HubMock.iTwinId, iModelName: "Test", description: "TestSubject" });
+
+    const b1 = await HubWrappers.downloadAndOpenBriefcase({ accessToken: "user1", iTwinId: HubMock.iTwinId, iModelId, noLock: true });
+    b1.channels.addAllowedChannel(ChannelControl.sharedChannelName);
+    b1.saveChanges();
+    const b2 = await HubWrappers.downloadAndOpenBriefcase({ accessToken: "user2", iTwinId: HubMock.iTwinId, iModelId, noLock: true });
+    b2.channels.addAllowedChannel(ChannelControl.sharedChannelName);
+    b2.saveChanges();
+
+    const schema = `<?xml version="1.0" encoding="UTF-8"?>
+    <ECSchema schemaName="TestDomain" alias="ts" version="01.00" xmlns="http://www.bentley.com/schemas/Bentley.ECXML.3.1">
+        <ECSchemaReference name="BisCore" version="01.00" alias="bis"/>
+        <ECEntityClass typeName="Test2dElement">
+            <BaseClass>bis:GraphicalElement2d</BaseClass>
+            <ECProperty propertyName="s" typeName="string"/>
+        </ECEntityClass>
+        <ECEntityClass typeName="Test3dElement">
+            <BaseClass>Test2dElement</BaseClass>
+            <ECProperty propertyName="k" typeName="string"/>
+        </ECEntityClass>
+    </ECSchema>`;
+
+    await b1.importSchemaStrings([schema]);
+    b1.saveChanges("b1");
+    await b1.pushChanges({ description: "b1" });
+    await b2.pullChanges();
+    chai.expect(b2.txns.hasPendingTxns).to.be.false;
+
+    b1.close();
+    b2.close();
+
+    HubMock.shutdown();
+  });
+});