Change MQTT sw_version and version text sensor to display config_hash
instead of build_time_str. Format: "(config hash 0xXXXXXXXX)"
Version sensor with hide_timestamp=false also includes build time:
"(config hash 0xXXXXXXXX, built: YYYY-MM-DD HH:MM:SS +ZZZZ)"
Change wifi component to use fnv1a_hash_extend(config_hash, ESPHOME_VERSION)
instead of fnv1_hash(compilation_time) for the preferences hash.
This ensures wifi settings are invalidated on config or version changes,
not just on recompilation.
Change sen5x, sgp30, and sgp4x components to use fnv1a_hash_extend()
starting with config_hash and ESPHOME_VERSION, then extending with the
sensor serial number. This replaces the previous use of fnv1_hash with
compilation_time.
This ensures baseline storage is invalidated on config or version
changes, not just on recompilation.
Keep the API DeviceInfo compilation_time field using the old
get_compilation_time_ref() format for backward compatibility.
The text sensor build_time_str continues to use the new ISO 8601 format.
Increase buffer from 24 to 26 bytes to accommodate the ISO 8601 format
with timezone: "YYYY-MM-DD HH:MM:SS +ZZZZ" (25 chars + null terminator).
The old format "Dec 15 2025, 18:14:59" was 20 chars, but the new format
needs 25 chars. The 24-byte buffer was truncating the timezone to "+00"
instead of "+0000".
Change the API's DeviceInfo response to use the new ISO 8601 format
with timezone for compilation_time field by calling get_build_time_string()
instead of get_compilation_time_ref().
Update the placeholder build_info_data.h to match the new format.
Update integration test to expect the new format for compilation_time.
Test verifies that:
- When source files change, build_info is regenerated with new timestamp
- When no files change, build_info is preserved with same timestamp
The test runs copy_src_tree() three times in the same environment:
1. Initial run creates build_info
2. Second run with no changes preserves the timestamp
3. Third run with changed source file regenerates with new timestamp
Add tests to cover:
- Detection of config_hash changes in existing build_info.json
- Detection of esphome_version changes in existing build_info.json
- Handling of invalid/corrupted build_info.json files
These tests cover the exception handling and change detection logic
in copy_src_tree() that checks the existing build_info.json.
Use YYYY-MM-DD HH:MM:SS +ZZZZ format instead of the locale-dependent
'%b %d %Y, %H:%M:%S' format. This provides:
- Unambiguous date format (YYYY-MM-DD)
- Timezone information
- Locale-independent formatting
- Better sortability and parseability
Example: "2025-12-15 16:30:27 +0000" instead of "Dec 15 2025, 16:30:27"
Tests validate the format using strptime with '%Y-%m-%d %H:%M:%S %z'.
I think we need to put a little more thought into whether we really
want the build time in each of these, or whether it should be just
the config_hash (perhaps extended with version, and in some cases
the component's own serial number or other identifier).
So put the old compilation_time_ and its access methods back, so
this PR only adds the *new* fields. We can migrate users over and
then remove the compilation_time_ separately.
