=== Empty expression tests ===
Empty expr SyntaxError: malformed f-string
Whitespace expr SyntaxError: malformed f-string
Whitespace expr: SyntaxError
Unterminated expr: SyntaxError
Whitespace + conversion: SyntaxError
Long expression: OK
Template.__str__ with large string: OK
Basic t-string: OK, result=Template(strings=('', ''), interpolations=(Interpolation('a', 'x', None, ''),))
Nested interpolations error: SyntaxError: invalid syntax
Escaped braces result: Template(strings=('', ''), interpolations=(Interpolation(42, 'x', None, '5{literal}'),))

=== Expression parser tests ===
Complex expr: OK

=== Lexer edge cases ===
Lexer NULL case: Tested via heapalloc_fail_tstring.py

=== Parser allocation edge cases ===
Deep nesting: OK
Very long expression: OK

=== Additional parser regression tests ===
Raw nested spec: "QUOTED"
Escaped quote spec: "QUOTED"
Escaped backslash spec: \n
Nested quoted spec: \
Literal brace error: SyntaxError: malformed f-string
Unterminated field: malformed f-string

=== Complex expression stress test ===
60 terms: PASS
100 terms: PASS

=== Stack expansion test (copy_parse_node) ===
Stack expansion: OK

=== Format spec with triple-quoted strings ===
Triple-quote in format spec: OK
Triple single-quote in format spec: OK

=== Format spec parse error (exception handler) ===
Parse error handler: OK
Parse error handler 2: OK

=== Large integer in t-string ===
Large integer: OK

=== Bytes in expression ===
Bytes in expression: OK

=== Boolean constants ===
Boolean constants: OK

=== None constant ===
None constant: OK

=== Deep nesting for rule stack expansion ===
Deep nesting (depth=80): OK