diff --git a/spacy/tests/test_cli_app.py b/spacy/tests/test_cli_app.py
index 873a3ff66..1ed51cd1f 100644
--- a/spacy/tests/test_cli_app.py
+++ b/spacy/tests/test_cli_app.py
@@ -1,8 +1,12 @@
 import os
 from pathlib import Path
+import pytest
 from typer.testing import CliRunner
 
+import spacy
 from spacy.cli._util import app
+from spacy.language import Language
+from spacy.tokens import DocBin
 from .util import make_tempdir
 
 
@@ -31,3 +35,178 @@ def test_convert_auto_conflict():
         assert "All input files must be same type" in result.stdout
         out_files = os.listdir(d_out)
         assert len(out_files) == 0
+
+
+NOOP_CONFIG = """
+[paths]
+train = null
+dev = null
+vectors = null
+init_tok2vec = null
+
+[system]
+seed = 0
+gpu_allocator = null
+
+[nlp]
+lang = "xx"
+pipeline = ["noop", "noop2"]
+disabled = []
+before_creation = null
+after_creation = null
+after_pipeline_creation = null
+batch_size = 1000
+tokenizer = {"@tokenizers":"spacy.Tokenizer.v1"}
+
+[components]
+
+[components.noop]
+factory = "noop"
+
+[components.noop2]
+factory = "noop2"
+
+[corpora]
+
+[corpora.dev]
+@readers = "spacy.Corpus.v1"
+path = ${paths.dev}
+gold_preproc = false
+max_length = 0
+limit = 0
+augmenter = null
+
+[corpora.train]
+@readers = "spacy.Corpus.v1"
+path = ${paths.train}
+gold_preproc = false
+max_length = 0
+limit = 0
+augmenter = null
+
+[training]
+seed = ${system.seed}
+gpu_allocator = ${system.gpu_allocator}
+dropout = 0.1
+accumulate_gradient = 1
+patience = 1600
+max_epochs = 0
+max_steps = 20000
+eval_frequency = 200
+frozen_components = []
+annotating_components = []
+dev_corpus = "corpora.dev"
+
+train_corpus = "corpora.train"
+before_to_disk = null
+before_update = null
+
+[training.batcher]
+@batchers = "spacy.batch_by_words.v1"
+discard_oversize = false
+tolerance = 0.2
+get_length = null
+
+[training.batcher.size]
+@schedules = "compounding.v1"
+start = 100
+stop = 1000
+compound = 1.001
+t = 0.0
+
+[training.logger]
+@loggers = "spacy.ConsoleLogger.v1"
+progress_bar = false
+
+[training.optimizer]
+@optimizers = "Adam.v1"
+beta1 = 0.9
+beta2 = 0.999
+L2_is_weight_decay = true
+L2 = 0.01
+grad_clip = 1.0
+use_averages = false
+eps = 0.00000001
+learn_rate = 0.001
+
+[training.score_weights]
+
+[pretraining]
+
+[initialize]
+vectors = ${paths.vectors}
+init_tok2vec = ${paths.init_tok2vec}
+vocab_data = null
+lookups = null
+before_init = null
+after_init = null
+
+[initialize.components]
+
+[initialize.tokenizer]
+"""
+
+
+@pytest.fixture
+def data_paths():
+    nlp = spacy.blank("xx")
+    doc = nlp("ok")
+    with make_tempdir() as tdir:
+        db = DocBin()
+        # debug data will *fail* if there aren't enough docs
+        for ii in range(100):
+            db.add(doc)
+        fpath = tdir / "data.spacy"
+        db.to_disk(fpath)
+
+        args = [
+            "--paths.train",
+            str(fpath),
+            "--paths.dev",
+            str(fpath),
+        ]
+        yield args
+
+
+@pytest.fixture
+def code_paths():
+    noop_base = """
+from spacy.language import Language
+
+@Language.component("{}")
+def noop(doc):
+    return doc
+"""
+
+    with make_tempdir() as temp_d:
+        # write code files to load
+        paths = []
+        for ff in ["noop", "noop2"]:
+            pyfile = temp_d / f"{ff}.py"
+            pyfile.write_text(noop_base.format(ff))
+            paths.append(pyfile)
+
+        args = ["--code", ",".join([str(pp) for pp in paths])]
+        yield args
+
+
+@pytest.fixture
+def noop_config():
+    with make_tempdir() as temp_d:
+        cfg = temp_d / "config.cfg"
+        cfg.write_text(NOOP_CONFIG)
+
+        yield cfg
+
+
+def test_multi_code_debug_data(code_paths, data_paths, noop_config):
+    # check that it fails without the code arg
+    result = CliRunner().invoke(app, ["debug", "data", str(noop_config), *data_paths])
+    assert result.exit_code == 1
+
+    # check that it succeeds with the code arg
+    code_arg = ["--code", ",".join([str(pp) for pp in code_paths])]
+    result = CliRunner().invoke(
+        app, ["debug", "data", str(noop_config), *data_paths, *code_paths]
+    )
+    assert result.exit_code == 0