commit 73cbd989428d8c0a3f69601506fddd2b6332ecb1
author Dmitri Prime <bolms@google.com> Thu Oct 17 13:32:35 2024 -0700
committer GitHub <noreply@github.com> Thu Oct 17 13:32:35 2024 -0700
tree 0fdb8eeaea1bfc49690a4d90bf0b077c2ff2b216
parent 46423da28a23f1b03e6024f2ba6c0863d408349e

Convert Location to a namedtuple, and associated cleanup (#205)

This change makes the `Location` dataclass, which does not change
frequently, into a new `SourceLocation` namedtuple, and changes the
`SourceLocation` serialization.  As a result, with this change:

*   `embossc` runs about 25% faster on a large (7kLOC) input; `python3
    -OO emboss` runs about 19% faster on the same input.
*   Serialized IR is about 45% smaller.

Details:

*   Replace the `ir_data.Location` dataclass with a new
    `parser_types.SourceLocation` namedtuple.  The rename helps clarify
    the difference between a location within source code
    (`SourceLocation`) and a location within a structure
    (`FieldLocation`).
*   Similarly, replace `ir_data.Position` with
    `parser_types.SourcePosition`.
*   Update any place that edits a `SourceLocation` with an appropriate
    assignment; e.g., `x.source_location.end = y` becomes
    `x.source_location = x.source_location._replace(end=y)`.  In most
    cases, several fields were updated consecutively; those updates are
    been merged.
*   Update the JSON serialization to use the compact format.
*   Replace `format_location()` and `format_position()` with
    `__str__()` methods on `SourceLocation` and `SourcePosition`,
    respectively.
*   Replace `parse_location()` and `parse_position()` with `from_str()`
    class methods on `SourceLocation` and `SourcePosition`,
    respectively.
*   Move the `make_location()` functionality into
    `SourceLocation.__new__()`.
*   Update `_to_dict` and `_from_dict` in `IrDataSerializer` to
    stringify and destringify `SourceLocation`.  It is tempting to
    try to do this during the JSON serialization step (with a `default=`
    parameter to `json.dumps` and an `object_hook=` parameter to
    `json.loads`), but it is tricky to get the `object_hook` to know
    when to convert.