Fix replacement for multiple substitutions

[speckins]

Since SubstitutionContext#substitute! uses while/#sub! to replace '?' in
the selector, and the replacement text contains that character, e.g.,
"(?-mix:\d+)", if the selector requires more than one replacement, the
replaced text is matched by the next iteration.

# given this assertion
assert_select "input[name=?][value=?]", /item-\d+/, /\d+/

# first iteration
"input[name=\"(?-mix:item-\\d+)\"][value=?]"

# second iteration
"input[name=\"(\"(?-mix:\\d+)\"-mix:item-\\d+)\"][value=?]"

This commit uses #gsub to avoid replacing already substituted text.

Fixes #75.

[rails-bot]

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[zzak]

@lastthyme Was there a reason you approved this? It doesn't seem like there has been any activity on this PR in nearly 3 years. 🤔

[speckins]

@zzak What kind of activity is necessary?

[zzak]

@speckins Just wondering if you had some context I might be missing about this PR 🤔

[speckins]

Originally I submitted an issue (#75) before the PR, but it appears they've since been disabled for this repo.

The assert_select method accepts RegExp arguments, which replace placeholders ("?") in the selector. However, due to the implementation of the method which performs the replacement, it does not work correctly for multiple RegExp arguments. This is because the current implementation doesn't resume matching after the last replacement; it starts over at the beginning of the string, which means it will match any "?" in the substituted text of the previous iteration. And since RegExp#to_s always (I think) contain "?", this means that assert_select cannot be used with more than one RegExp. (The behavior is also demonstrated in the commit message in the first comment.)

irb> /\d+/.to_s
=> "(?-mix:\\d+)"

I see that master has been active. I could rebase if you'd like.

[zzak]

@speckins Yes please! Thank you for elaborating on the problem 🙇

[speckins]

@zzak - I rebased on the current master; tests pass.

[zzak]

Thanks @speckins!

TBH I'm not really sure the current state of this gem, perhaps @seanpdoyle or @rafaelfranca can enlighten me? 🙏