Related:
- #15683
- #14551
- #849
- #12701
- #11527
# Description
Currently various commands have differing behavior regarding cell-paths
```nushell
{a: 1, A: 2} | get a A
# => ╭───┬───╮
# => │ 0 │ 2 │
# => │ 1 │ 2 │
# => ╰───┴───╯
{a: 1, A: 2} | select a A
# => ╭───┬───╮
# => │ a │ 1 │
# => │ A │ 2 │
# => ╰───┴───╯
{A: 1} | update a 2
# => Error: nu:🐚:column_not_found
# =>
# => × Cannot find column 'a'
# => ╭─[entry #62:1:1]
# => 1 │ {A: 1} | update a 2
# => · ───┬── ┬
# => · │ ╰── cannot find column 'a'
# => · ╰── value originates here
# => ╰────
```
Proposal: making cell-path access case-sensitive by default and adding
new syntax for case-insensitive parts, similar to optional (?) parts.
```nushell
{FOO: BAR}.foo
# => Error: nu:🐚:name_not_found
# =>
# => × Name not found
# => ╭─[entry #60:1:21]
# => 1 │ {FOO: BAR}.foo
# => · ─┬─
# => · ╰── did you mean 'FOO'?
# => ╰────
{FOO: BAR}.foo!
# => BAR
```
This would solve the problem of case sensitivity for all commands
without causing an explosion of flags _and_ make it more granular
Assigning to a field using a case-insensitive path is case-preserving.
```nushell
mut val = {FOO: "I'm FOO"}; $val
# => ╭─────┬─────────╮
# => │ FOO │ I'm FOO │
# => ╰─────┴─────────╯
$val.foo! = "I'm still FOO"; $val
# => ╭─────┬───────────────╮
# => │ FOO │ I'm still FOO │
# => ╰─────┴───────────────╯
```
For `update`, case-insensitive is case-preserving.
```nushell
{FOO: 1} | update foo! { $in + 1 }
# => ╭─────┬───╮
# => │ FOO │ 2 │
# => ╰─────┴───╯
```
`insert` can insert values into nested values so accessing into existing
columns is case-insensitive, but creating new columns uses the cell-path
as it is.
So `insert foo! ...` and `insert FOO! ...` would work exactly as they do
without `!`
```nushell
{FOO: {quox: 0}}
# => ╭─────┬──────────────╮
# => │ │ ╭──────┬───╮ │
# => │ FOO │ │ quox │ 0 │ │
# => │ │ ╰──────┴───╯ │
# => ╰─────┴──────────────╯
{FOO: {quox: 0}} | insert foo.bar 1
# => ╭─────┬──────────────╮
# => │ │ ╭──────┬───╮ │
# => │ FOO │ │ quox │ 0 │ │
# => │ │ ╰──────┴───╯ │
# => │ │ ╭─────┬───╮ │
# => │ foo │ │ bar │ 1 │ │
# => │ │ ╰─────┴───╯ │
# => ╰─────┴──────────────╯
{FOO: {quox: 0}} | insert foo!.bar 1
# => ╭─────┬──────────────╮
# => │ │ ╭──────┬───╮ │
# => │ FOO │ │ quox │ 0 │ │
# => │ │ │ bar │ 1 │ │
# => │ │ ╰──────┴───╯ │
# => ╰─────┴──────────────╯
```
`upsert` is tricky, depending on the input, the data might end up with
different column names in rows. We can either forbid case-insensitive
cell-paths for `upsert` or trust the user to keep their data in a
sensible shape.
This would be a breaking change as it would make existing cell-path
accesses case-sensitive, however the case-sensitivity is already
inconsistent and any attempt at making it consistent would be a breaking
change.
> What about `$env`?
1. Initially special case it so it keeps its current behavior.
2. Accessing environment variables with non-matching paths gives a
deprecation warning urging users to either use exact casing or use the
new explicit case-sensitivity syntax
3. Eventuall remove `$env`'s special case, making `$env` accesses
case-sensitive by default as well.
> `$env.ENV_CONVERSIONS`?
In addition to `from_string` and `to_string` add an optional field to
opt into case insensitive/preserving behavior.
# User-Facing Changes
- `get`, `where` and other previously case-insensitive commands are now
case-sensitive by default.
- `get`'s `--sensitive` flag removed, similar to `--ignore-errors` there
is now an `--ignore-case` flag that treats all parts of the cell-path as
case-insensitive.
- Users can explicitly choose the case case-sensitivity of cell-path
accesses or commands.
# Tests + Formatting
Existing tests required minimal modification. ***However, new tests are
not yet added***.
- 🟢 toolkit fmt
- 🟢 toolkit clippy
- 🟢 toolkit test
- 🟢 toolkit test stdlib
# After Submitting
- Update the website to include the new syntax
- Update [tree-sitter-nu](https://github.com/nushell/tree-sitter-nu)
---------
Co-authored-by: Bahex <17417311+Bahex@users.noreply.github.com>
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