bpo-46458: emit code for else of a try block immediately after the try body (GH-30751)

diff --git a/Lib/test/test_dis.py b/Lib/test/test_dis.py
index 72590649ea80c54cb98980fed67ee1231553819b..3e415a9605927b92aedce8a44fcbf73b57feb6b3 100644 (file)
--- a/Lib/test/test_dis.py
+++ b/Lib/test/test_dis.py
@@ -1172,75 +1172,67 @@ expected_opinfo_jumpy = [
   Instruction(opname='LOAD_CONST', opcode=100, arg=7, argval=0, argrepr='0', offset=110, starts_line=None, is_jump_target=False, positions=None),
   Instruction(opname='BINARY_OP', opcode=122, arg=11, argval=11, argrepr='/', offset=112, starts_line=None, is_jump_target=False, positions=None),
   Instruction(opname='POP_TOP', opcode=1, arg=None, argval=None, argrepr='', offset=114, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='JUMP_FORWARD', opcode=110, arg=14, argval=146, argrepr='to 146', offset=116, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='PUSH_EXC_INFO', opcode=35, arg=None, argval=None, argrepr='', offset=118, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='LOAD_GLOBAL', opcode=116, arg=2, argval='ZeroDivisionError', argrepr='ZeroDivisionError', offset=120, starts_line=22, is_jump_target=False, positions=None),
-  Instruction(opname='JUMP_IF_NOT_EXC_MATCH', opcode=121, arg=69, argval=138, argrepr='to 138', offset=122, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='POP_TOP', opcode=1, arg=None, argval=None, argrepr='', offset=124, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='LOAD_GLOBAL', opcode=116, arg=1, argval='print', argrepr='print', offset=126, starts_line=23, is_jump_target=False, positions=None),
-  Instruction(opname='LOAD_CONST', opcode=100, arg=8, argval='Here we go, here we go, here we go...', argrepr="'Here we go, here we go, here we go...'", offset=128, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='CALL_NO_KW', opcode=169, arg=1, argval=1, argrepr='', offset=130, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='POP_TOP', opcode=1, arg=None, argval=None, argrepr='', offset=132, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='POP_EXCEPT', opcode=89, arg=None, argval=None, argrepr='', offset=134, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='JUMP_FORWARD', opcode=110, arg=35, argval=208, argrepr='to 208', offset=136, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='RERAISE', opcode=119, arg=0, argval=0, argrepr='', offset=138, starts_line=22, is_jump_target=True, positions=None),
-  Instruction(opname='COPY', opcode=120, arg=3, argval=3, argrepr='', offset=140, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='POP_EXCEPT', opcode=89, arg=None, argval=None, argrepr='', offset=142, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='RERAISE', opcode=119, arg=1, argval=1, argrepr='', offset=144, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='LOAD_FAST', opcode=124, arg=0, argval='i', argrepr='i', offset=146, starts_line=25, is_jump_target=True, positions=None),
-  Instruction(opname='BEFORE_WITH', opcode=53, arg=None, argval=None, argrepr='', offset=148, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='STORE_FAST', opcode=125, arg=1, argval='dodgy', argrepr='dodgy', offset=150, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='LOAD_GLOBAL', opcode=116, arg=1, argval='print', argrepr='print', offset=152, starts_line=26, is_jump_target=False, positions=None),
-  Instruction(opname='LOAD_CONST', opcode=100, arg=9, argval='Never reach this', argrepr="'Never reach this'", offset=154, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='CALL_NO_KW', opcode=169, arg=1, argval=1, argrepr='', offset=156, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='POP_TOP', opcode=1, arg=None, argval=None, argrepr='', offset=158, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='LOAD_CONST', opcode=100, arg=0, argval=None, argrepr='None', offset=160, starts_line=25, is_jump_target=False, positions=None),
-  Instruction(opname='LOAD_CONST', opcode=100, arg=0, argval=None, argrepr='None', offset=162, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='LOAD_CONST', opcode=100, arg=0, argval=None, argrepr='None', offset=164, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='CALL_NO_KW', opcode=169, arg=3, argval=3, argrepr='', offset=166, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='POP_TOP', opcode=1, arg=None, argval=None, argrepr='', offset=168, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='JUMP_FORWARD', opcode=110, arg=25, argval=222, argrepr='to 222', offset=170, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='PUSH_EXC_INFO', opcode=35, arg=None, argval=None, argrepr='', offset=172, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='WITH_EXCEPT_START', opcode=49, arg=None, argval=None, argrepr='', offset=174, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='POP_JUMP_IF_TRUE', opcode=115, arg=93, argval=186, argrepr='to 186', offset=176, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='RERAISE', opcode=119, arg=2, argval=2, argrepr='', offset=178, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='COPY', opcode=120, arg=3, argval=3, argrepr='', offset=180, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='LOAD_FAST', opcode=124, arg=0, argval='i', argrepr='i', offset=116, starts_line=25, is_jump_target=False, positions=None),
+  Instruction(opname='BEFORE_WITH', opcode=53, arg=None, argval=None, argrepr='', offset=118, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='STORE_FAST', opcode=125, arg=1, argval='dodgy', argrepr='dodgy', offset=120, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='LOAD_GLOBAL', opcode=116, arg=1, argval='print', argrepr='print', offset=122, starts_line=26, is_jump_target=False, positions=None),
+  Instruction(opname='LOAD_CONST', opcode=100, arg=8, argval='Never reach this', argrepr="'Never reach this'", offset=124, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='CALL_NO_KW', opcode=169, arg=1, argval=1, argrepr='', offset=126, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='POP_TOP', opcode=1, arg=None, argval=None, argrepr='', offset=128, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='LOAD_CONST', opcode=100, arg=0, argval=None, argrepr='None', offset=130, starts_line=25, is_jump_target=False, positions=None),
+  Instruction(opname='LOAD_CONST', opcode=100, arg=0, argval=None, argrepr='None', offset=132, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='LOAD_CONST', opcode=100, arg=0, argval=None, argrepr='None', offset=134, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='CALL_NO_KW', opcode=169, arg=3, argval=3, argrepr='', offset=136, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='POP_TOP', opcode=1, arg=None, argval=None, argrepr='', offset=138, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='JUMP_FORWARD', opcode=110, arg=11, argval=164, argrepr='to 164', offset=140, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='PUSH_EXC_INFO', opcode=35, arg=None, argval=None, argrepr='', offset=142, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='WITH_EXCEPT_START', opcode=49, arg=None, argval=None, argrepr='', offset=144, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='POP_JUMP_IF_TRUE', opcode=115, arg=78, argval=156, argrepr='to 156', offset=146, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='RERAISE', opcode=119, arg=2, argval=2, argrepr='', offset=148, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='COPY', opcode=120, arg=3, argval=3, argrepr='', offset=150, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='POP_EXCEPT', opcode=89, arg=None, argval=None, argrepr='', offset=152, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='RERAISE', opcode=119, arg=1, argval=1, argrepr='', offset=154, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='POP_TOP', opcode=1, arg=None, argval=None, argrepr='', offset=156, starts_line=None, is_jump_target=True, positions=None),
+  Instruction(opname='POP_EXCEPT', opcode=89, arg=None, argval=None, argrepr='', offset=158, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='POP_TOP', opcode=1, arg=None, argval=None, argrepr='', offset=160, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='POP_TOP', opcode=1, arg=None, argval=None, argrepr='', offset=162, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='JUMP_FORWARD', opcode=110, arg=14, argval=194, argrepr='to 194', offset=164, starts_line=None, is_jump_target=True, positions=None),
+  Instruction(opname='PUSH_EXC_INFO', opcode=35, arg=None, argval=None, argrepr='', offset=166, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='LOAD_GLOBAL', opcode=116, arg=2, argval='ZeroDivisionError', argrepr='ZeroDivisionError', offset=168, starts_line=22, is_jump_target=False, positions=None),
+  Instruction(opname='JUMP_IF_NOT_EXC_MATCH', opcode=121, arg=93, argval=186, argrepr='to 186', offset=170, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='POP_TOP', opcode=1, arg=None, argval=None, argrepr='', offset=172, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='LOAD_GLOBAL', opcode=116, arg=1, argval='print', argrepr='print', offset=174, starts_line=23, is_jump_target=False, positions=None),
+  Instruction(opname='LOAD_CONST', opcode=100, arg=9, argval='Here we go, here we go, here we go...', argrepr="'Here we go, here we go, here we go...'", offset=176, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='CALL_NO_KW', opcode=169, arg=1, argval=1, argrepr='', offset=178, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='POP_TOP', opcode=1, arg=None, argval=None, argrepr='', offset=180, starts_line=None, is_jump_target=False, positions=None),
   Instruction(opname='POP_EXCEPT', opcode=89, arg=None, argval=None, argrepr='', offset=182, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='RERAISE', opcode=119, arg=1, argval=1, argrepr='', offset=184, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='POP_TOP', opcode=1, arg=None, argval=None, argrepr='', offset=186, starts_line=None, is_jump_target=True, positions=None),
-  Instruction(opname='POP_EXCEPT', opcode=89, arg=None, argval=None, argrepr='', offset=188, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='POP_TOP', opcode=1, arg=None, argval=None, argrepr='', offset=190, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='POP_TOP', opcode=1, arg=None, argval=None, argrepr='', offset=192, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='NOP', opcode=9, arg=None, argval=None, argrepr='', offset=194, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='LOAD_GLOBAL', opcode=116, arg=1, argval='print', argrepr='print', offset=196, starts_line=28, is_jump_target=False, positions=None),
-  Instruction(opname='LOAD_CONST', opcode=100, arg=10, argval="OK, now we're done", argrepr='"OK, now we\'re done"', offset=198, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='CALL_NO_KW', opcode=169, arg=1, argval=1, argrepr='', offset=200, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='POP_TOP', opcode=1, arg=None, argval=None, argrepr='', offset=202, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='LOAD_CONST', opcode=100, arg=0, argval=None, argrepr='None', offset=204, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='RETURN_VALUE', opcode=83, arg=None, argval=None, argrepr='', offset=206, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='NOP', opcode=9, arg=None, argval=None, argrepr='', offset=208, starts_line=23, is_jump_target=True, positions=None),
-  Instruction(opname='LOAD_GLOBAL', opcode=116, arg=1, argval='print', argrepr='print', offset=210, starts_line=28, is_jump_target=False, positions=None),
-  Instruction(opname='LOAD_CONST', opcode=100, arg=10, argval="OK, now we're done", argrepr='"OK, now we\'re done"', offset=212, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='CALL_NO_KW', opcode=169, arg=1, argval=1, argrepr='', offset=214, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='POP_TOP', opcode=1, arg=None, argval=None, argrepr='', offset=216, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='LOAD_CONST', opcode=100, arg=0, argval=None, argrepr='None', offset=218, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='RETURN_VALUE', opcode=83, arg=None, argval=None, argrepr='', offset=220, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='NOP', opcode=9, arg=None, argval=None, argrepr='', offset=222, starts_line=25, is_jump_target=True, positions=None),
-  Instruction(opname='LOAD_GLOBAL', opcode=116, arg=1, argval='print', argrepr='print', offset=224, starts_line=28, is_jump_target=False, positions=None),
-  Instruction(opname='LOAD_CONST', opcode=100, arg=10, argval="OK, now we're done", argrepr='"OK, now we\'re done"', offset=226, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='CALL_NO_KW', opcode=169, arg=1, argval=1, argrepr='', offset=228, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='POP_TOP', opcode=1, arg=None, argval=None, argrepr='', offset=230, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='LOAD_CONST', opcode=100, arg=0, argval=None, argrepr='None', offset=232, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='RETURN_VALUE', opcode=83, arg=None, argval=None, argrepr='', offset=234, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='PUSH_EXC_INFO', opcode=35, arg=None, argval=None, argrepr='', offset=236, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='LOAD_GLOBAL', opcode=116, arg=1, argval='print', argrepr='print', offset=238, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='LOAD_CONST', opcode=100, arg=10, argval="OK, now we're done", argrepr='"OK, now we\'re done"', offset=240, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='CALL_NO_KW', opcode=169, arg=1, argval=1, argrepr='', offset=242, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='POP_TOP', opcode=1, arg=None, argval=None, argrepr='', offset=244, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='RERAISE', opcode=119, arg=0, argval=0, argrepr='', offset=246, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='COPY', opcode=120, arg=3, argval=3, argrepr='', offset=248, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='POP_EXCEPT', opcode=89, arg=None, argval=None, argrepr='', offset=250, starts_line=None, is_jump_target=False, positions=None),
-  Instruction(opname='RERAISE', opcode=119, arg=1, argval=1, argrepr='', offset=252, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='JUMP_FORWARD', opcode=110, arg=10, argval=206, argrepr='to 206', offset=184, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='RERAISE', opcode=119, arg=0, argval=0, argrepr='', offset=186, starts_line=22, is_jump_target=True, positions=None),
+  Instruction(opname='COPY', opcode=120, arg=3, argval=3, argrepr='', offset=188, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='POP_EXCEPT', opcode=89, arg=None, argval=None, argrepr='', offset=190, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='RERAISE', opcode=119, arg=1, argval=1, argrepr='', offset=192, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='LOAD_GLOBAL', opcode=116, arg=1, argval='print', argrepr='print', offset=194, starts_line=28, is_jump_target=True, positions=None),
+  Instruction(opname='LOAD_CONST', opcode=100, arg=10, argval="OK, now we're done", argrepr='"OK, now we\'re done"', offset=196, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='CALL_NO_KW', opcode=169, arg=1, argval=1, argrepr='', offset=198, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='POP_TOP', opcode=1, arg=None, argval=None, argrepr='', offset=200, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='LOAD_CONST', opcode=100, arg=0, argval=None, argrepr='None', offset=202, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='RETURN_VALUE', opcode=83, arg=None, argval=None, argrepr='', offset=204, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='NOP', opcode=9, arg=None, argval=None, argrepr='', offset=206, starts_line=23, is_jump_target=True, positions=None),
+  Instruction(opname='LOAD_GLOBAL', opcode=116, arg=1, argval='print', argrepr='print', offset=208, starts_line=28, is_jump_target=False, positions=None),
+  Instruction(opname='LOAD_CONST', opcode=100, arg=10, argval="OK, now we're done", argrepr='"OK, now we\'re done"', offset=210, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='CALL_NO_KW', opcode=169, arg=1, argval=1, argrepr='', offset=212, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='POP_TOP', opcode=1, arg=None, argval=None, argrepr='', offset=214, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='LOAD_CONST', opcode=100, arg=0, argval=None, argrepr='None', offset=216, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='RETURN_VALUE', opcode=83, arg=None, argval=None, argrepr='', offset=218, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='PUSH_EXC_INFO', opcode=35, arg=None, argval=None, argrepr='', offset=220, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='LOAD_GLOBAL', opcode=116, arg=1, argval='print', argrepr='print', offset=222, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='LOAD_CONST', opcode=100, arg=10, argval="OK, now we're done", argrepr='"OK, now we\'re done"', offset=224, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='CALL_NO_KW', opcode=169, arg=1, argval=1, argrepr='', offset=226, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='POP_TOP', opcode=1, arg=None, argval=None, argrepr='', offset=228, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='RERAISE', opcode=119, arg=0, argval=0, argrepr='', offset=230, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='COPY', opcode=120, arg=3, argval=3, argrepr='', offset=232, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='POP_EXCEPT', opcode=89, arg=None, argval=None, argrepr='', offset=234, starts_line=None, is_jump_target=False, positions=None),
+  Instruction(opname='RERAISE', opcode=119, arg=1, argval=1, argrepr='', offset=236, starts_line=None, is_jump_target=False, positions=None),
 ]
 
 # One last piece of inspect fodder to check the default line number handling

diff --git a/Lib/test/test_exception_variations.py b/Lib/test/test_exception_variations.py
index aabac6d27701f643031a7782bb981af83e11a848..a83a41d2975db666c55acf1d24980d2fc508bfe4 100644 (file)
--- a/Lib/test/test_exception_variations.py
+++ b/Lib/test/test_exception_variations.py
@@ -1,7 +1,7 @@
 
 import unittest
 
-class ExceptionTestCase(unittest.TestCase):
+class ExceptTestCases(unittest.TestCase):
     def test_try_except_else_finally(self):
         hit_except = False
         hit_else = False
@@ -172,6 +172,127 @@ class ExceptionTestCase(unittest.TestCase):
         self.assertTrue(hit_finally)
         self.assertTrue(hit_except)
 
+    def test_nested_exception_in_except(self):
+        hit_else = False
+        hit_finally = False
+        hit_except = False
+        hit_inner_except = False
+        hit_inner_else = False
+
+        try:
+            try:
+                raise Exception('inner exception')
+            except:
+                hit_inner_except = True
+                raise Exception('outer exception')
+            else:
+                hit_inner_else = True
+        except:
+            hit_except = True
+        else:
+            hit_else = True
+        finally:
+            hit_finally = True
+
+        self.assertTrue(hit_inner_except)
+        self.assertFalse(hit_inner_else)
+        self.assertFalse(hit_else)
+        self.assertTrue(hit_finally)
+        self.assertTrue(hit_except)
+
+    def test_nested_exception_in_else(self):
+        hit_else = False
+        hit_finally = False
+        hit_except = False
+        hit_inner_except = False
+        hit_inner_else = False
+
+        try:
+            try:
+                pass
+            except:
+                hit_inner_except = True
+            else:
+                hit_inner_else = True
+                raise Exception('outer exception')
+        except:
+            hit_except = True
+        else:
+            hit_else = True
+        finally:
+            hit_finally = True
+
+        self.assertFalse(hit_inner_except)
+        self.assertTrue(hit_inner_else)
+        self.assertFalse(hit_else)
+        self.assertTrue(hit_finally)
+        self.assertTrue(hit_except)
+
+    def test_nested_exception_in_finally_no_exception(self):
+        hit_else = False
+        hit_finally = False
+        hit_except = False
+        hit_inner_except = False
+        hit_inner_else = False
+        hit_inner_finally = False
+
+        try:
+            try:
+                pass
+            except:
+                hit_inner_except = True
+            else:
+                hit_inner_else = True
+            finally:
+                hit_inner_finally = True
+                raise Exception('outer exception')
+        except:
+            hit_except = True
+        else:
+            hit_else = True
+        finally:
+            hit_finally = True
+
+        self.assertFalse(hit_inner_except)
+        self.assertTrue(hit_inner_else)
+        self.assertTrue(hit_inner_finally)
+        self.assertFalse(hit_else)
+        self.assertTrue(hit_finally)
+        self.assertTrue(hit_except)
+
+    def test_nested_exception_in_finally_with_exception(self):
+        hit_else = False
+        hit_finally = False
+        hit_except = False
+        hit_inner_except = False
+        hit_inner_else = False
+        hit_inner_finally = False
+
+        try:
+            try:
+                raise Exception('inner exception')
+            except:
+                hit_inner_except = True
+            else:
+                hit_inner_else = True
+            finally:
+                hit_inner_finally = True
+                raise Exception('outer exception')
+        except:
+            hit_except = True
+        else:
+            hit_else = True
+        finally:
+            hit_finally = True
+
+
+        self.assertTrue(hit_inner_except)
+        self.assertFalse(hit_inner_else)
+        self.assertTrue(hit_inner_finally)
+        self.assertFalse(hit_else)
+        self.assertTrue(hit_finally)
+        self.assertTrue(hit_except)
+
 
 class ExceptStarTestCases(unittest.TestCase):
     def test_try_except_else_finally(self):

diff --git a/Lib/test/test_sys_settrace.py b/Lib/test/test_sys_settrace.py
index e5fc88e1b6f59decac65a5e0c2c575c71800b590..fe6f7da0fd75810d7a55f3ee06a54758f05b6691 100644 (file)
--- a/Lib/test/test_sys_settrace.py
+++ b/Lib/test/test_sys_settrace.py
@@ -664,6 +664,38 @@ class TraceTestCase(unittest.TestCase):
              (14, 'line'),
              (14, 'return')])
 
+    def test_try_exception_in_else(self):
+
+        def func():
+            try:
+                try:
+                    3
+                except:
+                    5
+                else:
+                    7
+                    raise Exception
+                finally:
+                    10
+            except:
+                12
+            finally:
+                14
+
+        self.run_and_compare(func,
+            [(0, 'call'),
+             (1, 'line'),
+             (2, 'line'),
+             (3, 'line'),
+             (7, 'line'),
+             (8, 'line'),
+             (8, 'exception'),
+             (10, 'line'),
+             (11, 'line'),
+             (12, 'line'),
+             (14, 'line'),
+             (14, 'return')])
+
     def test_nested_loops(self):
 
         def func():

diff --git a/Misc/NEWS.d/next/Core and Builtins/2022-01-27-10-49-34.bpo-46458.5Gm3Gv.rst b/Misc/NEWS.d/next/Core and Builtins/2022-01-27-10-49-34.bpo-46458.5Gm3Gv.rst
new file mode 100644 (file)
index 0000000..25f9ca3
--- /dev/null
+++ b/Misc/NEWS.d/next/Core and Builtins/2022-01-27-10-49-34.bpo-46458.5Gm3Gv.rst
@@ -0,0 +1,4 @@
+Reorder code emitted by the compiler for a :keyword:`try`-:keyword:`except`
+block so that the :keyword:`else` block's code immediately follows the
+:keyword:`try` body (without a jump). This is more optimal for the happy
+path.

diff --git a/Python/compile.c b/Python/compile.c
index f1049fd931e1430f438bb2edb0d4c9467063b2f1..6883a4b01954ac3835ddda8c856a766af96df595 100644 (file)
--- a/Python/compile.c
+++ b/Python/compile.c
@@ -3353,15 +3353,14 @@ compiler_try_star_finally(struct compiler *c, stmt_ty s)
 static int
 compiler_try_except(struct compiler *c, stmt_ty s)
 {
-    basicblock *body, *orelse, *except, *end, *cleanup;
+    basicblock *body, *except, *end, *cleanup;
     Py_ssize_t i, n;
 
     body = compiler_new_block(c);
     except = compiler_new_block(c);
-    orelse = compiler_new_block(c);
     end = compiler_new_block(c);
     cleanup = compiler_new_block(c);
-    if (body == NULL || except == NULL || orelse == NULL || end == NULL || cleanup == NULL)
+    if (body == NULL || except == NULL || end == NULL || cleanup == NULL)
         return 0;
     ADDOP_JUMP(c, SETUP_FINALLY, except);
     compiler_use_next_block(c, body);
@@ -3370,7 +3369,11 @@ compiler_try_except(struct compiler *c, stmt_ty s)
     VISIT_SEQ(c, stmt, s->v.Try.body);
     compiler_pop_fblock(c, TRY_EXCEPT, body);
     ADDOP_NOLINE(c, POP_BLOCK);
-    ADDOP_JUMP_NOLINE(c, JUMP_FORWARD, orelse);
+    if (s->v.Try.orelse && asdl_seq_LEN(s->v.Try.orelse)) {
+        NEXT_BLOCK(c);
+        VISIT_SEQ(c, stmt, s->v.Try.orelse);
+    }
+    ADDOP_JUMP_NOLINE(c, JUMP_FORWARD, end);
     n = asdl_seq_LEN(s->v.Try.handlers);
     compiler_use_next_block(c, except);
 
@@ -3474,8 +3477,6 @@ compiler_try_except(struct compiler *c, stmt_ty s)
     ADDOP_I(c, RERAISE, 0);
     compiler_use_next_block(c, cleanup);
     POP_EXCEPT_AND_RERAISE(c);
-    compiler_use_next_block(c, orelse);
-    VISIT_SEQ(c, stmt, s->v.Try.orelse);
     compiler_use_next_block(c, end);
     return 1;
 }