Shell arithmetic syntax highlight breaks on multiple cases

[leagris]

Prerequisites

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  • Followed all applicable steps in the debugging guide: https://flight-manual.atom.io/hacking-atom/sections/debugging/
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Description

Shell arithmetic syntax highlighting breaks on multiple cases:

1. Base marker base# is treated as a comment marker
2. When base marker is turned into a comment, the following lines, variables are not highlighted.
3. Parenthesis in arithmetic expression breaks the (( )) delimiters detection.

Steps to Reproduce

1. Edit the following Bash script:

   #!/usr/bien/env bash
   echo "$((16#ff))"   # base# handled as comment marker
   echo "$((a=16#ff))" # variable highlighted ok
   a=42                # variable highlighted ok
   ((a=42))            # variable not highlighted
   a=42                # variable highlighted ok
   ((a=16#ff))         # variable not highlighted
   a=42                # breaks further highlighting
   a="$((~(-1 << 8)))" # parenthesis highlight broken

Expected behavior:

Same correct highlighting as sample code above as shown in github

Actual behavior:

Reproduces how often:

100% reproducible

Versions

Versions

• OS : Ubuntu 19.04
• Atom : 1.38.2
• Electron: 2.0.18
• Chrome : 61.0.3163.100
• Node : 8.9.3
• apm 2.1.7
• npm 6.2.0
• node 8.9.3 x64
• atom 1.38.2
• python 2.7.16
• git 2.20.1

Additional Information

none

[rsese]

Thanks again @leagris :+1: I can reproduce with on macOS 10.12.6 but not sure if this belongs in https://github.com/tree-sitter/tree-sitter-bash.

For example, I see that the issue with base# has already been reported: https://github.com/tree-sitter/tree-sitter-bash/issues/41.

I think that leaves 2 issues from your report, I don't think these have been reported?

((a=42))            # variable not highlighted

and:

a="$((~(-1 << 8)))" # parenthesis highlight broken

I'll see which repo the other maintainers think the issue belongs.

[TriMoon]

I was about to file a bug report for exactly this issue... Please fix asap :wink:

if test 0 -ne $((bDebug & 2#0001)); then
        ....
fi

Atom's highlighting/parsing bugs after the hash sign of 2#0001 A simple fix IMHO is to check for digits right infront of the hash sign....

[leagris]

@TriMoon or:

if ((bDebug & 2#0001)); then
  echo 'ok'
fi

or:

((bDebug & 2#0001)) && echo 'ok'

or: Oh! Well, it does not show the bug then!

((bDebug & 1)) && echo 'ok'

[TriMoon]

@leagris is that first example you give using if working on all shells? (eg. bash,zsh,dash,sh) It needs to be shell agnostic... Besides re-coding just to avoid highlighting bugs in some editor is not the way to go :wink:

[leagris]

@TriMoon Stand-alone arithmetic expressions like in 1 are undefined in POSIX but supported everywhere. Base specification with <base>#<number> in arithmetic expressions is undefined in POSIX as well, so I opted to use POSIX undefined stand-alone expressions as well :)

[leagris]

A simple fix IMHO is to check for digits right infront of the hash sign....

The base value can be a variable name, so checking for [:digit:]# would break this way.

The correct fix is to turn-off comments parsing within an arithmetic expression, as there is no comment allowed within it.