Add the logic to finish or abort merges

Author: pvigier

src/renderer/components/index-viewer.tsx

@@ -187,10 +187,14 @@ export class IndexViewer extends React.PureComponent<IndexViewerProps, IndexView
       const message = this.state.description ? 
         `${this.state.summary}\n\n${this.state.description}` :
         this.state.summary;
-      if (this.state.amend) {
-        await this.props.repo.amend(message);
+      if (this.props.repoState === RepoState.Merge) {
+        await this.props.repo.finishMerge(message);
       } else {
-        await this.props.repo.commit(message);
+        if (this.state.amend) {
+          await this.props.repo.amend(message);
+        } else {
+          await this.props.repo.commit(message);
+        }
       }
       // Close path viewer if it is open
       this.props.onPatchSelect(null, PatchType.Committed);
@@ -224,7 +228,9 @@ export class IndexViewer extends React.PureComponent<IndexViewerProps, IndexView
             disabled={this.state.unstagedPatches.length === 0}>
             Commit and merge
           </button>
-          <button className='red-button' type='submit'>
+          <button className='red-button'
+            type='button'
+            onClick={() => this.props.repo.abortMerge()}>
             Abort merge
           </button>
         </>

src/renderer/helpers/repo-wrapper.ts

@@ -563,6 +563,31 @@ export class RepoWrapper {
     }
   }
 
+  async finishMerge(message: string) {
+    try {
+      const author = this.getSignature();
+      const index = await this.repo.index();
+      const oid = await index.writeTree();
+      const mergeHeads = await this.getMergeHeads();
+      if (this.headCommit === null) {
+        throw new Error('Head not valid');
+      }
+      if (mergeHeads.length === 0) {
+        throw new Error('No merge head found');
+      }
+      await this.repo.createCommit('HEAD', author, author, message, oid, [this.headCommit, ...mergeHeads]);
+      await this.repo.stateCleanup();
+    } catch (e) {
+      this.onNotification(`Unable to merge: ${e.message}`, NotificationType.Error);
+    }
+  }
+
+  async abortMerge() {
+    if (this.repo.isMerging() && this.headCommit) {
+      await this.reset(this.headCommit, Git.Reset.TYPE.HARD);
+    }
+  }
+
   async fetchAll() {
     try {
       await this.repo.fetchAll(RepoWrapper.getCredentialsCallback());