Read quoted arguments from parameter files, and refuse a file that includes itself

[abashev]

Part of #40, split out of #45. Upstream report: google/google-java-format#421.

From upstream, with the author kept

google/google-java-format#931 by Karlheinz Friedberger (open upstream), its three commits squashed into one:

• an argument in an @argfile may be quoted with double or single quotes and then keeps its whitespace, so a path with a space in it is one path. Before, it became several arguments, each reported as "Skipping non-Java file", and the run still exited 0;
• an unclosed quote runs to the end of the file; escaped quotes are not handled, as upstream;
• a parameter file that includes itself is reported as "parameter file was included recursively" instead of overflowing the stack.

The one change for argfiles that worked before: a path that contains a ' or " is now read as a quoted string.

How it reads a file

ARG_MATCHER finds one token at a time: a string in double quotes (group 1), a string in single quotes (group 2), or a run of characters without whitespace or quotes (group 3). The quotes are not part of the value. paramFilesStack holds the argfiles being read right now; a file already on it is an error, and a file included twice one after the other is still fine.

The odd strings in paramsFileWithQuotesAndWhitespaces are edge cases, with +w marking an argument that contains whitespace: "'M' +w" keeps its single quotes, '"P" +w' keeps its double quotes, 'K +w is an unclosed quote at the end of a file, and "@@O +w is an escaped @ inside an unclosed quote.

Checked

• The quoting and recursion cases from Improve handling of parameters in @-files: add quote-handling for whitespaces in parameters. google/google-java-format#931 fail without the change. The nesting case passes either way and guards what already worked.
• ./gradlew :open-java-format:test on JDK 21: 1450 tests, all green.
• The jar formats the 15,747 files of the JDK 21 sources from one argfile, byte for byte as before.
• By hand: a quoted path with spaces in an argfile formats that file, and a self-including argfile prints the new error.