refactor(formatter): avoid formatting empty vec AST

[Dunqing]

Prepare for #16437.

[Dunqing]

• refactor(formatter, codegen): use Comment::newlines to checking if there is a newline around #16482
• refactor(formatter): remove format_only_if_breaks and FormatOnlyIfBreaks #16478
• refactor(formatter): remove BufferSnapshot #16476
• feat(formatter): add debug assertion to ensure that there is no empty content is passed in #16475
• perf(formatter): avoid using an indent with a empty content #16474
• refactor(formatter): check whether BlockIndent's content is empty in debug mode #16437
• refactor(formatter): avoid formatting empty vec AST #16436 👈 (View in Graphite)
• perf(formatter): early return when no comments need to be printed #16432
• main

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[codspeed-hq]

CodSpeed Performance Report

Merging #16436 will not alter performance

_{Comparing 12-03-refactor_formatter_avoid_formatting_empty_vec_ast (30026b2) with 12-03-perf_formatter_early_return_when_no_comments_need_to_be_printed (4ef403e)}

Summary

✅ 38 untouched
⏩ 7 skipped¹

Footnotes

1. 7 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩

[graphite-app]

Merge activity

• Dec 4, 7:25 AM UTC: leaysgur added this pull request to the Graphite merge queue.
• Dec 4, 7:38 AM UTC: Merged by the Graphite merge queue.