add tests, fix exceptiongroup dependency, add doc requirement in another place

IPython/core/tests/test_exceptiongroup_tb.py

@@ -0,0 +1,109 b''
+import unittest
+import re
+from IPython.utils.capture import capture_output
+import sys
+import pytest
+from tempfile import TemporaryDirectory
+from IPython.testing import tools as tt
+
+def _exceptiongroup_common(
+    outer_chain: str,
+    inner_chain: str,
+    native: bool,
+) -> None:
+    pre_raise = "exceptiongroup." if not native else ""
+    pre_catch = pre_raise if sys.version_info < (3, 11) else ""
+    filestr = f"""
+    {"import exceptiongroup" if not native else ""}
+    import pytest
+
+    def f(): raise ValueError("From f()")
+    def g(): raise BaseException("From g()")
+
+    def inner(inner_chain):
+        excs = []
+        for callback in [f, g]:
+            try:
+                callback()
+            except BaseException as err:
+                excs.append(err)
+        if excs:
+            if inner_chain == "none":
+                raise {pre_raise}BaseExceptionGroup("Oops", excs)
+            try:
+                raise SyntaxError()
+            except SyntaxError as e:
+                if inner_chain == "from":
+                    raise {pre_raise}BaseExceptionGroup("Oops", excs) from e
+                else:
+                    raise {pre_raise}BaseExceptionGroup("Oops", excs)
+
+    def outer(outer_chain, inner_chain):
+        try:
+            inner(inner_chain)
+        except {pre_catch}BaseExceptionGroup as e:
+            if outer_chain == "none":
+                raise
+            if outer_chain == "from":
+                raise IndexError() from e
+            else:
+                raise IndexError
+
+
+    outer("{outer_chain}", "{inner_chain}")
+    """
+    with capture_output() as cap:
+        ip.run_cell(filestr)
+
+    match_lines = []
+    if inner_chain == "another":
+        match_lines += [
+            "During handling of the above exception, another exception occurred:",
+        ]
+    elif inner_chain == 'from':
+        match_lines += [
+            "The above exception was the direct cause of the following exception:",
+        ]
+
+    match_lines += [
+        "  + Exception Group Traceback (most recent call last):",
+        f"  | {pre_catch}BaseExceptionGroup: Oops (2 sub-exceptions)",
+        "    | ValueError: From f()",
+        "    | BaseException: From g()",
+    ]
+
+    if outer_chain == "another":
+        match_lines += [
+            "During handling of the above exception, another exception occurred:",
+            "IndexError",
+        ]
+    elif outer_chain == "from":
+        match_lines += [
+            "The above exception was the direct cause of the following exception:",
+            "IndexError",
+        ]
+
+    error_lines = cap.stderr.split("\n")
+
+    err_index = match_index = 0
+    for expected in match_lines:
+        for i,actual in enumerate(error_lines):
+            if actual == expected:
+                error_lines = error_lines[i+1:]
+                break
+        else:
+            assert False, f'{expected} not found in cap.stderr'
+
[e-mail](
+        sys.version_info < (3, 11), reason="Native ExceptionGroup not implemented"
+        )
[e-mail]("outer_chain", ["none", "from", "another"])
[e-mail]("inner_chain", ["none", "from", "another"])
+def test_native_exceptiongroup(outer_chain, inner_chain) -> None:
+    _exceptiongroup_common(outer_chain, inner_chain, native=True)
+
[e-mail]("outer_chain", ["none", "from", "another"])
[e-mail]("inner_chain", ["none", "from", "another"])
+def test_native_exceptiongroup(outer_chain, inner_chain) -> None:
+    pytest.importorskip("exceptiongroup")
+    _exceptiongroup_common(outer_chain, inner_chain, native=False)

docs/environment.yml

@@ -8,6 +8,7 b' dependencies:'
   - sphinx>=4.2
   - sphinx_rtd_theme
   - numpy
+  - exceptiongroup
   - testpath
   - matplotlib
   - pip

setup.cfg

@@ -33,7 +33,7 b' install_requires ='
     backcall
     colorama; sys_platform == "win32"
     decorator
-    exceptiongroup; python_version<'3.10'
+    exceptiongroup; python_version<'3.11'
     jedi>=0.16
     matplotlib-inline
     pexpect>4.3; sys_platform != "win32"