bpo-39912: Raise appropriate exceptions in filterwarnings() and simplefilter() (GH-18878)

1 files changed, 18 insertions, 12 deletions

diff --git a/Lib/warnings.py b/Lib/warnings.py
index 924f872172d..b8ff078569d 100644
--- a/Lib/warnings.py
+++ b/Lib/warnings.py
@@ -139,14 +139,18 @@ def filterwarnings(action, message="", category=Warning, module="", lineno=0,
     'lineno' -- an integer line number, 0 matches all warnings
     'append' -- if true, append to the list of filters
     """
-    assert action in ("error", "ignore", "always", "default", "module",
-                      "once"), "invalid action: %r" % (action,)
-    assert isinstance(message, str), "message must be a string"
-    assert isinstance(category, type), "category must be a class"
-    assert issubclass(category, Warning), "category must be a Warning subclass"
-    assert isinstance(module, str), "module must be a string"
-    assert isinstance(lineno, int) and lineno >= 0, \
-           "lineno must be an int >= 0"
+    if action not in {"error", "ignore", "always", "default", "module", "once"}:
+        raise ValueError(f"invalid action: {action!r}")
+    if not isinstance(message, str):
+        raise TypeError("message must be a string")
+    if not isinstance(category, type) or not issubclass(category, Warning):
+        raise TypeError("category must be a Warning subclass")
+    if not isinstance(module, str):
+        raise TypeError("module must be a string")
+    if not isinstance(lineno, int):
+        raise TypeError("lineno must be an int")
+    if lineno < 0:
+        raise ValueError("lineno must be an int >= 0")
 
     if message or module:
         import re
@@ -172,10 +176,12 @@ def simplefilter(action, category=Warning, lineno=0, append=False):
     'lineno' -- an integer line number, 0 matches all warnings
     'append' -- if true, append to the list of filters
     """
-    assert action in ("error", "ignore", "always", "default", "module",
-                      "once"), "invalid action: %r" % (action,)
-    assert isinstance(lineno, int) and lineno >= 0, \
-           "lineno must be an int >= 0"
+    if action not in {"error", "ignore", "always", "default", "module", "once"}:
+        raise ValueError(f"invalid action: {action!r}")
+    if not isinstance(lineno, int):
+        raise TypeError("lineno must be an int")
+    if lineno < 0:
+        raise ValueError("lineno must be an int >= 0")
     _add_filter(action, None, category, None, lineno, append=append)
 
 def _add_filter(*item, append):