Dodge StringIndexOutOfBoundsException on empty files (prettier/css)

[dweiss]

Trivial fix for empty css files causing out-of-bounds exception with prettier:

> Task :dcs:contexts:frontend:spotlessJs
Step 'prettier-format' found problem in '...\SearchApp.css':
begin 0, end -1, length 0
java.lang.StringIndexOutOfBoundsException: begin 0, end -1, length 0
        at java.base/java.lang.String.checkBoundsBeginEnd(String.java:3756)
        at java.base/java.lang.String.substring(String.java:1902)
        at com.diffplug.spotless.npm.PrettierFormatterStep$PrettierFilePathPassingFormatterFunc.applyWithFile(PrettierFormatterStep.java:116)
        at com.diffplug.spotless.FormatterFunc$NeedsFile.apply(FormatterFunc.java:154)

[dweiss]

Not necessarily for immediate merging, but shows where the problem is (zero-length files).

[nedtwigg]

Maybe if (unix.trim().isEmpty()) { return unix; }

[dweiss]

Absolutely - any way is good to dodge that exception. 👍 Please feel free to correct this in the code directly, not worth a roundtrip on the PR. Thank you for the software, it's excellent.

[nedtwigg]

Fixed in commit referenced above, thanks for finding bug and reporting.

[nedtwigg]

Fixed in plugin-gradle 5.9.0 and plugin-maven 2.7.0.