Files
esphome/tests/unit_tests/analyze_memory/test_ram_strings.py
T

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4.6 KiB
Python

"""Tests for RAM symbol analysis in the RAM strings analyzer."""
from pathlib import Path
from unittest.mock import patch
from esphome.analyze_memory.ram_strings import RamStringsAnalyzer, SectionInfo
# nm -S --size-sort output with the newlib lock mutexes: nine global
# symbols that are all aliases of two local StaticSemaphore_t objects.
NM_OUTPUT_WITH_ALIASES = """\
3ffb4400 00000010 B small_symbol
3ffb43c8 00000054 B __lock___atexit_recursive_mutex
3ffb43c8 00000054 B __lock___env_recursive_mutex
3ffb43c8 00000054 B __lock___malloc_recursive_mutex
3ffb43c8 00000054 B __lock___sfp_recursive_mutex
3ffb43c8 00000054 B __lock___sinit_recursive_mutex
3ffb43c8 00000054 b s_common_recursive_mutex
3ffb441c 00000054 B __lock___arc4random_mutex
3ffb441c 00000054 B __lock___at_quick_exit_mutex
3ffb441c 00000054 B __lock___dd_hash_mutex
3ffb441c 00000054 B __lock___tz_mutex
3ffb441c 00000054 b s_common_mutex
"""
def _make_analyzer(tmp_path) -> RamStringsAnalyzer:
"""Create an analyzer with a dummy ELF and a .dram0.bss section."""
elf = tmp_path / "firmware.elf"
elf.write_bytes(b"\x7fELF")
analyzer = RamStringsAnalyzer(str(elf), platform="esp32")
analyzer.sections[".dram0.bss"] = SectionInfo(".dram0.bss", 0x3FFB0000, 0x10000)
return analyzer
def _run_symbol_analysis(analyzer: RamStringsAnalyzer, nm_output: str) -> None:
"""Run _analyze_symbols with mocked nm output."""
with (
patch(
"esphome.analyze_memory.ram_strings.find_tool",
return_value="nm",
),
patch.object(analyzer, "_run_command", return_value=nm_output),
):
analyzer._analyze_symbols()
def test_aliased_symbols_counted_once(tmp_path: Path) -> None:
"""Symbols sharing an address are one object, not one per name."""
analyzer = _make_analyzer(tmp_path)
_run_symbol_analysis(analyzer, NM_OUTPUT_WITH_ALIASES)
# Three distinct addresses, so three symbols
assert len(analyzer.ram_symbols) == 3
total = sum(s.size for s in analyzer.ram_symbols)
assert total == 0x10 + 0x54 + 0x54
def test_aliases_recorded_on_first_symbol(tmp_path: Path) -> None:
"""Extra names at the same address are kept as aliases."""
analyzer = _make_analyzer(tmp_path)
_run_symbol_analysis(analyzer, NM_OUTPUT_WITH_ALIASES)
by_addr = {s.address: s for s in analyzer.ram_symbols}
assert len(by_addr[0x3FFB43C8].aliases) == 5
assert len(by_addr[0x3FFB441C].aliases) == 4
assert by_addr[0x3FFB4400].aliases == []
assert "s_common_mutex" in by_addr[0x3FFB441C].aliases
def test_alias_count_shown_in_report(tmp_path: Path) -> None:
"""The large symbols table notes how many aliases were merged."""
analyzer = _make_analyzer(tmp_path)
_run_symbol_analysis(analyzer, NM_OUTPUT_WITH_ALIASES)
report = analyzer.generate_report()
assert "(+5 aliases)" in report
assert "(+4 aliases)" in report
# Each lock name appears at most once in the report
assert report.count("__lock___") == 2
def test_global_name_preferred_over_local_alias(tmp_path: Path) -> None:
"""A global name becomes the primary even when nm lists a local first."""
analyzer = _make_analyzer(tmp_path)
nm_output = """\
3ffb43c8 00000054 b s_common_recursive_mutex
3ffb43c8 00000054 B __lock___atexit_recursive_mutex
3ffb43c8 00000054 B __lock___malloc_recursive_mutex
"""
_run_symbol_analysis(analyzer, nm_output)
(symbol,) = analyzer.ram_symbols
assert symbol.name == "__lock___atexit_recursive_mutex"
assert symbol.sym_type == "B"
assert sorted(symbol.aliases) == [
"__lock___malloc_recursive_mutex",
"s_common_recursive_mutex",
]
def test_alias_note_survives_name_truncation(tmp_path: Path) -> None:
"""Long names are truncated but the alias note is kept intact."""
analyzer = _make_analyzer(tmp_path)
long_name = "a_very_long_symbol_name_that_exceeds_the_column_width_by_far"
nm_output = f"""\
3ffb43c8 00000054 B {long_name}
3ffb43c8 00000054 B other_name
"""
_run_symbol_analysis(analyzer, nm_output)
report = analyzer.generate_report()
row = next(line for line in report.splitlines() if "(+1 aliases)" in line)
name_column = row[:50].rstrip()
assert name_column.endswith("(+1 aliases)")
assert name_column.startswith("a_very_long_symbol_name")
def test_symbols_outside_ram_sections_skipped(tmp_path: Path) -> None:
"""Symbols outside known RAM sections are ignored entirely."""
analyzer = _make_analyzer(tmp_path)
nm_output = "40080000 00000100 B not_in_ram\n"
_run_symbol_analysis(analyzer, nm_output)
assert analyzer.ram_symbols == []