!10074 Fix a testcase error when shuffle is above cache

From: @lixiachen
Reviewed-by: @liucunwei,@pandoublefeng
Signed-off-by: @liucunwei,@liucunwei

mindspore/ccsrc/minddata/dataset/engine/datasetops/cache_merge_op.cc

@@ -275,24 +275,14 @@ Status CacheMergeOp::Accept(NodePass *p, bool *modified) {
 }
 
 Status CacheMergeOp::EoeReceived(int32_t worker_id) {
-  // If we are in a repeat path, send the eoe up.
-  // Otherwise ignore it.
-  if (op_total_repeats_ != 1) {
-    return DatasetOp::EoeReceived(worker_id);
-  }
-  return Status::OK();
+  // Send the eoe up.
+  MS_LOG(DEBUG) << "Cache merge sending eoe";
+  return DatasetOp::EoeReceived(worker_id);
 }
 
 // Base-class override for handling cases when an eof is received.
 Status CacheMergeOp::EofReceived(int32_t worker_id) {
-  // If we are not in a repeated path, then the merge op gets a eof by itself, without first
-  // getting an eoe.  However, the logic demands that all epochs close with an eoe first before eof.
-  // Thus, generate an eoe first, before flowing up the eof in the non-repeated case. Base class
-  // provides that for us.
-  if (op_total_repeats_ == 1) {
-    MS_LOG(DEBUG) << "Cache merge sending eoe";
-    RETURN_IF_NOT_OK(DatasetOp::EoeReceived(worker_id));
-  }
+  // Send the eof up.
   MS_LOG(DEBUG) << "Cache merge sending eof";
   return DatasetOp::EofReceived(worker_id);
 }

mindspore/dataset/engine/cache_client.py

@@ -23,7 +23,10 @@ from ..core.validator_helpers import type_check, check_uint32, check_uint64, che
 
 class DatasetCache:
     """
-    A client to interface with tensor caching service
+    A client to interface with tensor caching service.
+
+    For details, please check `Chinese tutorial <https://www.mindspore.cn/tutorial/training/zh-CN/master/advanced_use/enable_cache.html>`_,
+    `Chinese programming guide <https://www.mindspore.cn/doc/programming_guide/zh-CN/master/cache.html?highlight=datasetcache>`_.
 
     Args:
         session_id (int): A user assigned session id for the current pipeline.
@@ -34,9 +37,6 @@ class DatasetCache:
         num_connections (int, optional): Number of tcp/ip connections (default=12).
         prefetch_size (int, optional): Prefetch size (default=20).
 
-    Tutorials:
-        https://www.mindspore.cn/doc/programming_guide/zh-CN/master/cache.html?highlight=datasetcache
-        https://www.mindspore.cn/tutorial/training/zh-CN/master/advanced_use/enable_cache.html
     """
 
     def __init__(self, session_id, size=0, spilling=False, hostname=None, port=None, num_connections=None,

tests/ut/python/dataset/test_cache_map.py

@@ -1857,6 +1857,40 @@ def test_cache_map_cifar3():
     logger.info("test_cache_map_cifar3 Ended.\n")
 
 
+@pytest.mark.skipif(os.environ.get('RUN_CACHE_TEST') != 'TRUE', reason="Require to bring up cache server")
+def test_cache_map_cifar4():
+    """
+    Test mappable cifar10 leaf with cache op right over the leaf, and shuffle op over the cache op
+
+       shuffle
+         |
+       cache
+         |
+      Cifar10
+    """
+
+    logger.info("Test cache map cifar4")
+    if "SESSION_ID" in os.environ:
+        session_id = int(os.environ['SESSION_ID'])
+    else:
+        raise RuntimeError("Testcase requires SESSION_ID environment variable")
+
+    some_cache = ds.DatasetCache(session_id=session_id, size=0, spilling=True)
+    ds1 = ds.Cifar10Dataset(CIFAR10_DATA_DIR, num_samples=10, cache=some_cache)
+    ds1 = ds1.shuffle(10)
+
+    num_epoch = 1
+    iter1 = ds1.create_dict_iterator(num_epochs=num_epoch)
+
+    epoch_count = 0
+    for _ in range(num_epoch):
+        assert sum([1 for _ in iter1]) == 10
+        epoch_count += 1
+    assert epoch_count == num_epoch
+
+    logger.info("test_cache_map_cifar4 Ended.\n")
+
+
 @pytest.mark.skipif(os.environ.get('RUN_CACHE_TEST') != 'TRUE', reason="Require to bring up cache server")
 def test_cache_map_voc1():
     """