Commit Graph

6 Commits

Author SHA1 Message Date
YizhePKU
6c649809d3
Rewrite run_external.rs (#12921)
This PR is a complete rewrite of `run_external.rs`. The main goal of the
rewrite is improving readability, but it also fixes some bugs related to
argument handling and the PATH variable (fixes
https://github.com/nushell/nushell/issues/6011).

I'll discuss some technical details to make reviewing easier.

## Argument handling

Quoting arguments for external commands is hard. Like, *really* hard.
We've had more than a dozen issues and PRs dedicated to quoting
arguments (see Appendix) but the current implementation is still buggy.

Here's a demonstration of the buggy behavior:

```nu
let foo = "'bar'"
^touch $foo            # This creates a file named `bar`, but it should be `'bar'`
^touch ...[ "'bar'" ]  # Same
```

I'll describe how this PR deals with argument handling.

First, we'll introduce the concept of **bare strings**. Bare strings are
**string literals** that are either **unquoted** or **quoted by
backticks** [^1]. Strings within a list literal are NOT considered bare
strings, even if they are unquoted or quoted by backticks.

When a bare string is used as an argument to external process, we need
to perform tilde-expansion, glob-expansion, and inner-quotes-removal, in
that order. "Inner-quotes-removal" means transforming from
`--option="value"` into `--option=value`.

## `.bat` files and CMD built-ins

On Windows, `.bat` files and `.cmd` files are considered executable, but
they need `CMD.exe` as the interpreter. The Rust standard library
supports running `.bat` files directly and will spawn `CMD.exe` under
the hood (see
[documentation](https://doc.rust-lang.org/std/process/index.html#windows-argument-splitting)).
However, other extensions are not supported [^2].

Nushell also supports a selected number of CMD built-ins. The problem
with CMD is that it uses a different set of quoting rules. Correctly
quoting for CMD requires using
[Command::raw_arg()](https://doc.rust-lang.org/std/os/windows/process/trait.CommandExt.html#tymethod.raw_arg)
and manually quoting CMD special characters, on top of quoting from the
Nushell side. ~~I decided that this is too complex and chose to reject
special characters in CMD built-ins instead [^3]. Hopefully this will
not affact real-world use cases.~~ I've implemented escaping that works
reasonably well.

## `which-support` feature

The `which` crate is now a hard dependency of `nu-command`, making the
`which-support` feature essentially useless. The `which` crate is
already a hard dependency of `nu-cli`, and we should consider removing
the `which-support` feature entirely.

## Appendix

Here's a list of quoting-related issues and PRs in rough chronological
order.

* https://github.com/nushell/nushell/issues/4609
* https://github.com/nushell/nushell/issues/4631
* https://github.com/nushell/nushell/issues/4601
  * https://github.com/nushell/nushell/pull/5846
* https://github.com/nushell/nushell/issues/5978
  * https://github.com/nushell/nushell/pull/6014
* https://github.com/nushell/nushell/issues/6154
  * https://github.com/nushell/nushell/pull/6161
* https://github.com/nushell/nushell/issues/6399
  * https://github.com/nushell/nushell/pull/6420
  * https://github.com/nushell/nushell/pull/6426
* https://github.com/nushell/nushell/issues/6465
* https://github.com/nushell/nushell/issues/6559
  * https://github.com/nushell/nushell/pull/6560

[^1]: The idea that backtick-quoted strings act like bare strings was
introduced by Kubouch and briefly mentioned in [the language
reference](https://www.nushell.sh/lang-guide/chapters/strings_and_text.html#backtick-quotes).

[^2]: The documentation also said "running .bat scripts in this way may
be removed in the future and so should not be relied upon", which is
another reason to move away from this. But again, quoting for CMD is
hard.

[^3]: If anyone wants to try, the best resource I found on the topic is
[this](https://daviddeley.com/autohotkey/parameters/parameters.htm).
2024-05-23 02:05:27 +00:00
Wind
ac4125f8ed
fix range semantic in detect_columns, str substring, str index-of (#12894)
# Description
Fixes: https://github.com/nushell/nushell/issues/7761

It's still unsure if we want to change the `range semantic` itself, but
it's good to keep range semantic consistent between nushell commands.

# User-Facing Changes
### Before
```nushell
❯ "abc" | str substring 1..=2
b
```
### After
```nushell
❯ "abc" | str substring 1..=2
bc
```

# Tests + Formatting
Adjust tests to fit new behavior
2024-05-22 20:00:58 +03:00
Ian Manske
baeba19b22
Make get_full_help take &dyn Command (#12903)
# Description
Changes `get_full_help` to take a `&dyn Command` instead of multiple
arguments (`&Signature`, `&Examples` `is_parser_keyword`). All of these
arguments can be gathered from a `Command`, so there is no need to pass
the pieces to `get_full_help`.

This PR also fixes an issue where the search terms are not shown if
`--help` is used on a command.
2024-05-19 19:56:33 +02:00
Wind
1b8eb23785
allow passing float value to custom command (#12879)
# Description
Fixes: #12691 

In `parse_short_flag`, it only checks special cases for
`SyntaxShape::Int`, `SyntaxShape::Number` to allow a flag to be a
number. This pr adds `SyntaxShape::Float` to allow a flag to be float
number.

# User-Facing Changes
This is possible after this pr:
```nushell
def spam [val: float] { $val }; 
spam -1.4
```

# Tests + Formatting
Added 1 test
2024-05-16 10:50:29 +02:00
Wind
155934f783
make better messages for incomplete string (#12868)
# Description
Fixes: #12795

The issue is caused by an empty position of `ParseError::UnexpectedEof`.
So no detailed message is displayed.
To fix the issue, I adjust the start of span to `span.end - 1`. In this
way, we can make sure that it never points to an empty position.

After lexing item, I also reorder the unclosed character checking . Now
it will be checking unclosed opening delimiters first.

# User-Facing Changes
After this pr, it outputs detailed error message for incomplete string
when running scripts.

## Before
```
❯ nu -c "'ab"
Error: nu::parser::unexpected_eof

  × Unexpected end of code.
   ╭─[source:1:4]
 1 │ 'ab
   ╰────
> ./target/debug/nu -c "r#'ab"
Error: nu::parser::unexpected_eof

  × Unexpected end of code.
   ╭─[source:1:6]
 1 │ r#'ab
   ╰────
```
## After
```
> nu -c "'ab"
Error: nu::parser::unexpected_eof

  × Unexpected end of code.
   ╭─[source:1:3]
 1 │ 'ab
   ·   ┬
   ·   ╰── expected closing '
   ╰────
> ./target/debug/nu -c "r#'ab"
Error: nu::parser::unexpected_eof

  × Unexpected end of code.
   ╭─[source:1:5]
 1 │ r#'ab
   ·     ┬
   ·     ╰── expected closing '#
   ╰────
```


# Tests + Formatting
Added some tests for incomplete string.

---------

Co-authored-by: Ian Manske <ian.manske@pm.me>
2024-05-15 01:14:11 +00:00
francesco-gaglione
c4dca5fe03
Merged tests to produce a single binary (#12826)
This PR should close #7147 

# Description
Merged src/tests into /tests to produce a single binary.

![image](https://github.com/nushell/nushell/assets/94604837/84726469-d447-4619-b6d1-2d1415d0f42e)

# User-Facing Changes
No user facing changes

# Tests + Formatting
Moved tests. Tollkit check pr pass.

# After Submitting

---------

Co-authored-by: Ian Manske <ian.manske@pm.me>
2024-05-13 13:37:53 +00:00