feat(fixers): handle multiline reraise

src/tests/fixers_test.py

@@ -49,10 +49,17 @@ def setup(self):
         self.fixer = RaiseWithoutCauseFixer()
 
     def create_raise_no_cause_violation(
-        self, line: int, except_line: int = -1, exception_name: Optional[str] = None
+        self,
+        line: int,
+        except_line: int = -1,
+        exception_name: Optional[str] = None,
+        end_lineno: Optional[int] = None,
     ):
         code, _ = codes.RERAISE_NO_CAUSE
-        node_mock = MagicMock(spec=ast.Raise, lineno=line)
+        if not end_lineno:
+            end_lineno = line
+
+        node_mock = MagicMock(spec=ast.Raise, lineno=line, end_lineno=end_lineno)
         except_node_mock = MagicMock(spec=ast.ExceptHandler, lineno=except_line)
         return RaiseWithoutCauseViolation(
             code, line, 0, "msg", "filename", node_mock, except_node_mock, exception_name
@@ -83,3 +90,19 @@ def test_with_exception_name(self):
         assert_ast_is_valid(results)
         assert_unmodified_lines(lines, results, offending_offset)
         assert results[offending_offset].endswith("raise MyException() from error\n")
+
+    def test_multiline_raise(self):
+        lines = read_sample_lines("except_reraise_no_cause", dir="autofix")
+        expected_modified_offsets = (38, 45)
+        offending_offset = 40
+        dependent_offset, ending_modified_offset = expected_modified_offsets
+        violation = self.create_raise_no_cause_violation(
+            offending_offset + 1, dependent_offset + 1, end_lineno=ending_modified_offset + 1
+        )
+
+        results = self.fixer.perform_fix(lines, violation)
+
+        assert_ast_is_valid(results)
+        assert_unmodified_lines(lines, results, *expected_modified_offsets)
+        assert results[dependent_offset].endswith("except Exception as ex:\n")
+        assert results[ending_modified_offset].endswith(") from ex  # multiline end!\n")

src/tests/samples/autofix/except_reraise_no_cause.py

@@ -43,4 +43,4 @@ def longer_reraise():
             2,
             3,
             4,
-        )
+        )  # multiline end!

src/tryceratops/fixers/exception_block.py

@@ -99,10 +99,19 @@ def _fix_except_handler(self, all_lines: List[str], offending_node: ast.ExceptHa
     def _fix_raise_no_cause(
         self, all_lines: List[str], violation: RaiseWithoutCauseViolation, exception_name: str
     ):
-        # TODO: What if this raise is multi-line?
-        guilty_line = all_lines[violation.line - 1]
-        new_line = re.sub(r"raise (.*)", rf"raise \1 from {exception_name}", guilty_line)
-        all_lines[violation.line - 1] = new_line
+        endline = violation.node.end_lineno or violation.line
+        is_singleline = violation.line == endline
+
+        if is_singleline:
+            fix_offset = violation.line - 1
+            guilty_line = all_lines[fix_offset]
+            new_line = re.sub(r"raise (.*)", rf"raise \1 from {exception_name}", guilty_line)
+        else:
+            fix_offset = endline - 1
+            guilty_line = all_lines[fix_offset]
+            new_line = re.sub(r"(\))(.*)", rf"\1 from {exception_name}\2", guilty_line)
+
+        all_lines[fix_offset] = new_line
 
     def perform_fix(self, lines: List[str], violation: RaiseWithoutCauseViolation) -> List[str]:
         all_lines = lines[:]