fix mypy

Author: Fidget-Spinner

Tools/cases_generator/tier1_generator.py

@@ -128,7 +128,7 @@ def uses_this(inst: Instruction) -> bool:
     return False
 
 
-def write_single_inst(out: CWriter, emitter: Emitter, name: str, inst: Instruction):
+def write_single_inst(out: CWriter, emitter: Emitter, name: str, inst: Instruction) -> None:
     needs_this = uses_this(inst)
     unused_guard = "(void)this_instr;\n" if inst.family is None else ""
     if inst.properties.needs_prev:

Tools/cases_generator/tier1_tail_call_generator.py

@@ -33,7 +33,7 @@
 
 TARGET_LABEL = "TAIL_CALL_TARGET"
 
-def generate_label_handlers(infile: TextIO, outfile: TextIO):
+def generate_label_handlers(infile: TextIO, outfile: TextIO) -> None:
     out = CWriter(outfile, 0, False)
     str_in = infile.read()
     # https://stackoverflow.com/questions/8303488/regex-to-match-any-character-including-new-lines