how do I search for a pattern starting with "-"?

[tgray]

What version of ripgrep are you using?

macOS homebrew:
ripgrep 12.0.1
-SIMD -AVX (compiled)
+SIMD +AVX (runtime)

also on Windows precompiled:
ripgrep 12.0.1 (rev 1d5b101)
-SIMD -AVX (compiled)
+SIMD +AVX (runtime)

How did you install ripgrep?

macOS: homebrew
Windows: compiled binary

What operating system are you using ripgrep on?

macOS 10.14.6
Windows 10 something

Describe your bug.

Trying to use rg to search for a literal string that starts with a '-', specifically markdown style check boxes '- [ ]'.

What are the steps to reproduce the behavior?

rg -F '- [ ]' .

or

rg -F "- [ ]" .

Running the search by escaping the leading dash works fine, but defeats the purpose of using -F in my opinion.

What is the actual behavior?

Normal and debug output are the same.

rg -F '- [ ]' --debug .
error: Found argument '- ' which wasn't expected, or isn't valid in this context

USAGE:

    rg [OPTIONS] PATTERN [PATH ...]
    rg [OPTIONS] [-e PATTERN ...] [-f PATTERNFILE ...] [PATH ...]
    rg [OPTIONS] --files [PATH ...]
    rg [OPTIONS] --type-list
    command | rg [OPTIONS] PATTERN

For more information try --help

What is the expected behavior?

rg should have searched the literal string '- [ ]' in the current directory.

[BurntSushi]

This is correct and expected behavior. The -F flag is a red herring here. If your pattern starts with a -, then you must either precede it with the -e flag or use -- to indicate that all subsequent arguments are positional. This is documented in the man page:

A regular expression used for searching. To match a pattern beginning with a dash, use the -e/--regexp option.

So you'll want rg -F -e '- [ ]' or rg -F -- '- [ ]'.

Running the search by escaping the leading dash works fine

This is a different search. There is no escaping when using -F, so if you use \- [ ], then you'll actually be searching for a literal \\ followed by a -:

$ echo '- [ ]' | rg -F '\- [ ]'
$ echo '\- [ ]' | rg -F '\- [ ]'
\- [ ]
$ echo '- [ ]' | rg -F -e '- [ ]'
- [ ]

Note that grep has the same exact behavior here and the exact same work-arounds.

[BurntSushi]

Moved this to a discussion, since this is more of a question of behavior even though it was reported as a bug.