Various debugger improvements

- disables globals
- can opt out of filtering frames
- can limit number of frames

jax/_src/debugger/core.py

@@ -80,7 +80,7 @@ def from_frameinfo(cls, frame_info) -> DebuggerFrame:
     return DebuggerFrame(
         filename=frame_info.filename,
         locals=frame_info.frame.f_locals,
-        globals=frame_info.frame.f_globals,
+        globals={},
         code_context=frame_info.code_context,
         source=source,
         lineno=frame_info.lineno,
@@ -113,19 +113,45 @@ def register_debugger(name: str, debugger: Debugger, priority: int) -> None:
 debug_lock = threading.Lock()
 
 
-def breakpoint(*, ordered: bool = False, backend=None, **kwargs):  # pylint: disable=redefined-builtin
-  """Enters a breakpoint at a point in a program."""
+def breakpoint(*, backend: Optional[str] = None, filter_frames: bool = True,
+               num_frames: Optional[int] = None, ordered: bool = False,
+               **kwargs):  # pylint: disable=redefined-builtin
+  """Enters a breakpoint at a point in a program.
+
+  Args:
+    backend: The debugger backend to use. By default, picks the highest priority
+      debugger and in the absence of other registered debuggers, falls back to
+      the CLI debugger.
+    filter_frames: Whether or not to filter out JAX-internal stack frames from
+      the traceback. Since some libraries, like Flax, also make user of JAX's
+      stack frame filtering system, this option can also affect whether stack
+      frames from libraries are filtered.
+    num_frames: The number of frames above the current stack frame to make
+      available for inspection in the interactive debugger.
+    ordered: A keyword only argument used to indicate whether or not the
+      staged out computation will enforce ordering of this ``debug_print``
+      with respect to other ordered ``debug_print`` calls.
+
+  Returns:
+    None.
+  """
   frame_infos = inspect.stack()
-  # Filter out internal frames
-  frame_infos = [
-      frame_info for frame_info in frame_infos
-      if traceback_util.include_frame(frame_info.frame)
-  ]
-  frames = [
-      DebuggerFrame.from_frameinfo(frame_info) for frame_info in frame_infos
-  ]
   # Throw out first frame corresponding to this function
-  frames = frames[1:]
+  frame_infos = frame_infos[1:]
+  if num_frames is not None:
+    frame_infos = frame_infos[:num_frames]
+  # Filter out internal frames
+  if filter_frames:
+    frames = [
+        DebuggerFrame.from_frameinfo(frame_info)
+        for frame_info in frame_infos
+        if traceback_util.include_frame(frame_info.frame)
+    ]
+  else:
+    frames = [
+        DebuggerFrame.from_frameinfo(frame_info)
+        for frame_info in frame_infos
+    ]
   flat_args, frames_tree = tree_util.tree_flatten(frames)
 
   def _breakpoint_callback(*flat_args):

tests/debugger_test.py

@@ -59,6 +59,8 @@ def tearDownModule():
 if jaxlib.version < (0, 3, 15):
   disabled_backends.append("tpu")
 
+foo = 2
+
 class CliDebuggerTest(jtu.JaxTestCase):
 
   @jtu.skip_on_devices(*disabled_backends)
@@ -321,8 +323,6 @@ def g(x):
       \(jdb\) """.format(re.escape(repr(arr))))
       g(jnp.arange(8, dtype=jnp.int32))
       jax.effects_barrier()
-      print(stdout.getvalue())
-      print(expected)
       self.assertRegex(stdout.getvalue(), expected)
 
   @jtu.skip_on_devices(*disabled_backends)
@@ -344,10 +344,70 @@ def f(x):
     \(jdb\) """)
     f(2.)
     jax.effects_barrier()
-    print(stdout.getvalue())
-    print(expected)
     self.assertRegex(stdout.getvalue(), expected)
 
 
+  @jtu.skip_on_devices(*disabled_backends)
+  def test_debugger_accesses_globals(self):
+    stdin, stdout = make_fake_stdin_stdout(["p foo", "c"])
+
+    @jax.jit
+    def g():
+      debugger.breakpoint(stdin=stdin, stdout=stdout, backend="cli")
+
+    expected = _format_multiline(r"""
+    Entering jdb:
+    \(jdb\) \*\*\* NameError: name 'foo' is not defined
+    \(jdb\) """)
+    g()
+    jax.effects_barrier()
+    self.assertRegex(stdout.getvalue(), expected)
+
+  @jtu.skip_on_devices(*disabled_backends)
+  def test_can_limit_num_frames(self):
+    stdin, stdout = make_fake_stdin_stdout(["u", "p x", "c"])
+
+    def g():
+      debugger.breakpoint(stdin=stdin, stdout=stdout, backend="cli",
+                          num_frames=2)
+
+    @jax.jit
+    def f():
+      x = 2
+      g()
+      return x
+
+    _ = f()
+    expected = _format_multiline(r"""
+    Entering jdb:
+    \(jdb\) .*
+    .*
+    .*
+    .*
+    .*
+    .*
+    .*
+    \(jdb\) 2
+    \(jdb\) """)
+    jax.effects_barrier()
+    self.assertRegex(stdout.getvalue(), expected)
+
+    stdin, stdout = make_fake_stdin_stdout(["u", "u", "c"])
+
+    def g2():
+      debugger.breakpoint(stdin=stdin, stdout=stdout, backend="cli",
+                          num_frames=2)
+
+    @jax.jit
+    def f2():
+      x = 2
+      g2()
+      return x
+
+    expected = ".*At topmost frame.*"
+    _ = f2()
+    jax.effects_barrier()
+    self.assertRegex(stdout.getvalue(), expected)
+
 if __name__ == '__main__':
   absltest.main(testLoader=jtu.JaxTestLoader())