Display multiline help nicely.

[benjyw]

This includes:

• Respecting any embedded newlines in the option help string.
• Formatting option values (defaults, current value) nicely
  when they are large lists and dicts.

[ci skip-rust-tests]

[benjyw]

[benjyw]

Note: uses executable tool help as the motivating use-case. So, among other things, expands the wrapping boundary from 80 to 96 to accommodate that case well.

[Eric-Arellano]

Thanks! You'll want to update a few other places, too:

▶ rg -C1 '\b80\b' -g '*.py'
src/python/pants/help/help_printer.py
83-                name = cyan(name)
84:            description_lines = textwrap.wrap(descr, 80 - chars_before_description)
85-            if len(description_lines) > 1:

src/python/pants/help/help_formatter.py
78-            f"{indent}{'  ' if i != 0 else ''}{self._maybe_cyan(s)}"
79:            for i, s in enumerate(wrap(f"{choices}", 80))
80-        ]
--
98-        ]
99:        description_lines = [f"{indent}{s}" for s in wrap(ohi.help, 80)]
100-        lines = [

src/python/pants/option/parser.py
424-                ),
425:                80,
426-            )
--
434-            ),
435:            80,
436-        )

src/python/pants/backend/pants_info/list_target_types.py
67-        else:
68:            description_lines = textwrap.wrap(self.description, 80 - chars_before_description)
69-            if len(description_lines) > 1:
--
160-        if self.description:
161:            lines.extend(f"{indent}{line}" for line in textwrap.wrap(self.description, 80))
162-        return "\n".join(f"{indent}{line}" for line in lines)
--
234-                    "information for a particular target type.",
235:                    80,
236-                ),

src/python/pants/core/goals/test.py
314-            console.print_stderr(
315:                f"{result.address.reference():80}.....{result.test_result.status.value:>10}"
316-            )

It'd probably be good to de-magic-number this. I only didn't do that at first because I don't know where to put it without causing dep cycles.

[benjyw]

Not sure we need to change how other things wrap - those can stay at 80 I think.