From 6546d1f7257d986c2598dd2ebd2bbd8d04285585 Mon Sep 17 00:00:00 2001
From: Florian Dahlitz <f2dahlitz@freenet.de>
Date: Mon, 25 May 2020 13:53:56 +0200
Subject: [PATCH] Prevent pytest from printing ConftestImportFailure traceback

---
 changelog/6956.bugfix.rst |  1 +
 src/_pytest/nodes.py      |  3 +++
 testing/python/collect.py |  9 +++------
 testing/test_reports.py   | 12 ++++++++++++
 4 files changed, 19 insertions(+), 6 deletions(-)
 create mode 100644 changelog/6956.bugfix.rst

diff --git a/changelog/6956.bugfix.rst b/changelog/6956.bugfix.rst
new file mode 100644
index 000000000..a88ef94b6
--- /dev/null
+++ b/changelog/6956.bugfix.rst
@@ -0,0 +1 @@
+Prevent pytest from printing ConftestImportFailure traceback to stdout.
diff --git a/src/_pytest/nodes.py b/src/_pytest/nodes.py
index 2f5f9bdb8..4c2a0a3a7 100644
--- a/src/_pytest/nodes.py
+++ b/src/_pytest/nodes.py
@@ -19,6 +19,7 @@ from _pytest._code.code import ReprExceptionInfo
 from _pytest.compat import cached_property
 from _pytest.compat import TYPE_CHECKING
 from _pytest.config import Config
+from _pytest.config import ConftestImportFailure
 from _pytest.config import PytestPluginManager
 from _pytest.deprecated import NODE_USE_FROM_PARENT
 from _pytest.fixtures import FixtureDef
@@ -340,6 +341,8 @@ class Node(metaclass=NodeMeta):
             return excinfo.value.formatrepr()
         if self.config.getoption("fulltrace", False):
             style = "long"
+        if excinfo.type is ConftestImportFailure:  # type: ignore
+            excinfo = ExceptionInfo.from_exc_info(excinfo.value.excinfo)  # type: ignore
         else:
             tb = _pytest._code.Traceback([excinfo.traceback[-1]])
             self._prunetraceback(excinfo)
diff --git a/testing/python/collect.py b/testing/python/collect.py
index 2807cacc9..cbc798ad8 100644
--- a/testing/python/collect.py
+++ b/testing/python/collect.py
@@ -1251,7 +1251,7 @@ def test_syntax_error_with_non_ascii_chars(testdir):
     result.stdout.fnmatch_lines(["*ERROR collecting*", "*SyntaxError*", "*1 error in*"])
 
 
-def test_collecterror_with_fulltrace(testdir):
+def test_collect_error_with_fulltrace(testdir):
     testdir.makepyfile("assert 0")
     result = testdir.runpytest("--fulltrace")
     result.stdout.fnmatch_lines(
@@ -1259,15 +1259,12 @@ def test_collecterror_with_fulltrace(testdir):
             "collected 0 items / 1 error",
             "",
             "*= ERRORS =*",
-            "*_ ERROR collecting test_collecterror_with_fulltrace.py _*",
-            "",
-            "*/_pytest/python.py:*: ",
-            "_ _ _ _ _ _ _ _ *",
+            "*_ ERROR collecting test_collect_error_with_fulltrace.py _*",
             "",
             ">   assert 0",
             "E   assert 0",
             "",
-            "test_collecterror_with_fulltrace.py:1: AssertionError",
+            "test_collect_error_with_fulltrace.py:1: AssertionError",
             "*! Interrupted: 1 error during collection !*",
         ]
     )
diff --git a/testing/test_reports.py b/testing/test_reports.py
index 13f593215..64d86e953 100644
--- a/testing/test_reports.py
+++ b/testing/test_reports.py
@@ -396,6 +396,18 @@ class TestReportSerialization:
         # for same reasons as previous test, ensure we don't blow up here
         loaded_report.longrepr.toterminal(tw_mock)
 
+    def test_report_prevent_ConftestImportFailure_hiding_exception(self, testdir):
+        sub_dir = testdir.tmpdir.join("ns").ensure_dir()
+        sub_dir.join("conftest").new(ext=".py").write("import unknown")
+
+        result = testdir.runpytest_subprocess(".")
+        result.stdout.fnmatch_lines(
+            ["E   ModuleNotFoundError: No module named 'unknown'"]
+        )
+        result.stdout.no_fnmatch_line(
+            "ERROR  - _pytest.config.ConftestImportFailure: ModuleNotFoundError:*"
+        )
+
 
 class TestHooks:
     """Test that the hooks are working correctly for plugins"""