Fix HashJoin hanging for non-autoStarted iterators

comunica · Jun 14, 2024 · 8ec9c78 · 8ec9c78
1 parent 36d70cb
commit 8ec9c78
Showing 1 changed file with 16 additions and 15 deletions.
diff --git a/join/HashJoin.js b/join/HashJoin.js
@@ -23,30 +23,27 @@ class HashJoin extends AsyncIterator
         this.left.on('error', (error) => this.destroy(error));
         this.right.on('error', (error) => this.destroy(error));
 
-        if (this.left.readable || this.right.readable)
-        {
-            this.readable = true;
-        }
+        this.readable = false;
 
         this.left.on('end', allowJoining.bind(this));
 
         function allowJoining ()
         {
-            if (this.leftMap.size <= 0)
-                return this.close();
             this.readable = true;
             this.right.on('readable', () => this.readable = true);
             this.right.on('end', () => { if (!this.hasResults()) this._end(); });
         }
 
         this.on('newListener', (eventName) =>
         {
-            if (eventName === 'data' && !this.addedDataListener)
+            if (eventName === 'data')
             {
-                this.addedDataListener = true;
-                this._addDataListener();
+                this._addDataListenerIfNeeded();
             }
-        })
+        });
+        if (this.left.readable)
+            this._addDataListenerIfNeeded();
+        this.left.on('readable', () => this._addDataListenerIfNeeded());
     }
 
     hasResults ()
@@ -63,11 +60,7 @@ class HashJoin extends AsyncIterator
 
     read ()
     {
-        if (!this.addedDataListener)
-        {
-            this.addedDataListener = true;
-            this._addDataListener();
-        }
+        this._addDataListenerIfNeeded();
 
         while(true) {
             if (this.ended || !this.readable)
@@ -98,6 +91,14 @@ class HashJoin extends AsyncIterator
         }
     }
 
+    _addDataListenerIfNeeded() {
+        if (!this.addedDataListener)
+        {
+            this.addedDataListener = true;
+            this._addDataListener();
+        }
+    }
+
     _addDataListener()
     {
         this.left.on('data', addItem.bind(this));