Add no-breakpoint checker

This adds a checker for calls to ``breakpoint()``
or ``sys.breakpointhook()``.
This closes pylint-dev#3692

ChangeLog

@@ -37,6 +37,10 @@ Release date: TBA
 
   Closes #3878
 
+* Added ``no-breakpoint``: Emitted when breakpoint() or sys.breakpointhook() calls are found
+
+  Closes #3692
+
 
 
 What's New in Pylint 2.9.6?

doc/whatsnew/2.10.rst

@@ -16,6 +16,10 @@ New checkers
 
   Closes #3826
 
+* Added ``no-breakpoint``: Emitted when breakpoint() or sys.breakpointhook() calls are found
+
+  Closes #3692
+
 
 Other Changes
 =============

pylint/checkers/stdlib.py

@@ -55,6 +55,7 @@
 SUBPROCESS_POPEN = "subprocess.Popen"
 SUBPROCESS_RUN = "subprocess.run"
 OPEN_MODULE = "_io"
+BREAKPOINTS = ("builtins.breakpoint", "sys.breakpointhook")
 
 
 DEPRECATED_MODULES = {
@@ -434,6 +435,12 @@ class StdlibChecker(DeprecatedMixin, BaseChecker):
             "Using the system default implicitly can create problems on other operating systems. "
             "See https://www.python.org/dev/peps/pep-0597/",
         ),
+        "W1515": (
+            "Leaving breakpoint() or sys.breakpointhook() in production code is unrecommended",
+            "no-breakpoint",
+            "Calls to breakpoint() and sys.breakpointhook() should be removed from code that "
+            "is not actively being debugged.",
+        ),
     }
 
     def __init__(self, linter=None):
@@ -495,6 +502,7 @@ def _check_shallow_copy_environ(self, node):
         "subprocess-run-check",
         "deprecated-class",
         "unspecified-encoding",
+        "no-breakpoint",
     )
     def visit_call(self, node):
         """Visit a Call node."""
@@ -531,6 +539,8 @@ def visit_call(self, node):
                         self._check_env_function(node, inferred)
                     elif name == SUBPROCESS_RUN:
                         self._check_for_check_kw_in_run(node)
+                    elif name in BREAKPOINTS:
+                        self.add_message("no-breakpoint", node=node)
                 self.check_deprecated_method(node, inferred)
         except astroid.InferenceError:
             return

tests/functional/n/no/no_breakpoint_py37.py

@@ -0,0 +1,6 @@
+# pylint: disable=missing-docstring,no-init
+
+import sys
+
+breakpoint()  # [no-breakpoint]
+sys.breakpointhook()  # [no-breakpoint]

tests/functional/n/no/no_breakpoint_py37.rc

@@ -0,0 +1,2 @@
+[testoptions]
+min_pyver=3.7

tests/functional/n/no/no_breakpoint_py37.txt

@@ -0,0 +1,2 @@
+no-breakpoint:5:0::"Leaving breakpoint() or sys.breakpointhook() in production code is unrecommended"
+no-breakpoint:6:0::"Leaving breakpoint() or sys.breakpointhook() in production code is unrecommended"