Adds minimal support for Array of Tables (AoT) #15
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Inline tables are a cool feature of the TOML, and very useful as elements of an array. However there are some circumstances that they are explicitly discouraged by spec itself. For example when dumping a list of dicts that in turn have lists inside of them, `tomli-w` will introduce line breaks inside of inline tables, which is not recommended by the spec This situation was first described in issue hukkin#12. Please notice this usage pattern is not that uncommon. We can find examples of this nesting in the wild, like the ones used in `mypy` configuration: https://mypy.readthedocs.io/en/stable/config_file.html#using-a-pyproject-toml-file
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Co-authored-by: Taneli Hukkinen <3275109+hukkin@users.noreply.github.com>
There might be a chance any-not is slightly more costly than not-all (although if it exists, the performance difference should be negligible)
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Thank you very much for the review @hukkin. I added the missing test and also fixed somethings regarding simply committing the suggestions via GitHub interface 😝 (I also reverted back to not-all instead of all-any, just because there might be a negligible performance penalty of flipping each Boolean but I admit that is very much a micro-optimisation that lacks benchmarking). |
tomli_w/_writer.py
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| # In the following line we use `repr(obj)` as an approximation for the | ||
| # TOML representation of an inline-table when `obj` is a dict, | ||
| # (for the purposes of roughly estimating the line length) | ||
| return len(repr(obj)) < LONG_LINE_HEURISTIC |
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| return len(repr(obj)) < LONG_LINE_HEURISTIC | |
| return len(format_literal(obj)) < LONG_LINE_HEURISTIC |
Would this work? It's probably more expensive, but would probably allow us to be actually precise about the line length
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I suppose it would (I haven't checked for infinite recursion though)
It is just important to have in mind that format_literal will still not consider the indentation inside an array (so in the end the condition will be implicitly LONG_LINE_HEURISTIC + indentation_len)
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I added your suggestion, the tests work so I suspect the recursion is fine 😝
Please feel free to revert the last commit if you change your mind about the precision/cost tradeoff 😄.
| # TOML representation of an inline-table when `obj` is a dict, | ||
| # (for the purposes of roughly estimating the line length) | ||
| return len(repr(obj)) < LONG_LINE_HEURISTIC | ||
| max_len = LONG_LINE_HEURISTIC - (INDENT_LENGTH * nest_level) |
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Here I think a nest_level argument (despite not necessary), makes more obvious and easier to understand.
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Thanks a lot for this! Tell me if you need a release soon and I'll make one. Otherwise I may wait until Python 3.6 removal or another feature. |
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Thanks @hukkin. I am waiting for this feature for my https://github.com/abravalheri/ini2toml project, but on the other hand I also have to wait for a couple of fixes in |
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👍 the CI of this PR should push v0.4.0 to PyPI for you #19 Thanks once more! |
Inline tables are a cool feature of the TOML, and very useful as elements of an array.
However there are some circumstances that they are explicitly discouraged by spec itself.
For example when dumping a list of dicts that in turn have lists inside of them,
tomli-wwill introduce line breaks inside of inline tables, which is not recommended by the specThis situation was first described in issue #12.
Please notice this usage pattern is not that uncommon. We can find examples of this nesting in the wild, like the ones used in
mypyconfiguration:https://mypy.readthedocs.io/en/stable/config_file.html#using-a-pyproject-toml-file