Rust: allow arrays in function parameters

[simias]

I noticed that ctags wouldn't generate a function entry for a signature like:

fn foo(arr: [u32; 3]) {}

The problem was that the parser stopped as soon as a ';' was encountered, probably assuming that it would be a statement delimiter and not an array type.

The fix is to keep track of brackets and ignore ';' if we have at least one opened bracket.

While I was at it I also reject the signature if the brackets aren't balanced, which means that the parser is now a little more strict than it was before and a (broken) function like this one will now be rejected:

fn bad(p: &[u32) {}

[coveralls]

Coverage increased (+0.002%) to 86.843% when pulling 2920975 on simias:fix/rust-array-param into c77c95a on universal-ctags:master.

[codecov]

Codecov Report

Merging #2612 into master will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master    #2612   +/-   ##
=======================================
  Coverage   86.73%   86.73%           
=======================================
  Files         183      183           
  Lines       38787    38793    +6     
=======================================
+ Hits        33643    33649    +6     
  Misses       5144     5144           

Impacted Files	Coverage Δ
parsers/rust.c	91.43% <100.00%> (+0.13%)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update c77c95a...2920975. Read the comment docs.

[masatake]

The change looks fine to me.
Could you add a test case for this?
See https://docs.ctags.io/en/latest/units.html to know how to write a test case.
See also files under Units/parser-rust.r.
See also commit 4ab2053 as an example.
You don't have to add Makefile.am, Makefile.in and Makefile. They are generated by autogen.sh and configure.

Thank you.

[simias]

Hello @masatake and thank you for the feedback.

The 2nd commit adds a test for array parameters the existing rust-test_input test: 6300265

Do you want me to create a new test specifically for this change?

[simias]

I just squashed the two commits for simplicity.

[masatake]

Thank you.