Js-beautify: HTML: Proposal to organize the attribute-wrapping settings

Extracted from #1297.

What we have

wrap_attributes:

• auto - enables wrapping of attributes.
• force - first attribute stays, others wrapped with "wrap_attributes_indent_size"
• force-aligned - the first attribute stays, others wrapped and aligned with the first one
• force-expand-multiline - If there are more than 1 atribute, ALL attributes are wrapped no matter what and indented with "wrap_attributes_indent_size". AND: the closing '>' of the opening tag is also on the new line. This mode is currently broken, produces wrongly indented files :(

There are also multiple effort to provide some additional modes that deal with wrapping of long html elements with multiple attributes: #1285 and #1262.

I think that there are multiple (orthogonal) concerns here and putting them all into single value would create more confusion and weird option names explosion if we are to handle all cases.

So, let's separate wrapping, aligning and number of attributes per line, etc.

Proposal

wrap_attributes_mode:

• none - We just don't wrap attributes, period. (needed?)
• auto - Normal attribute wrapping, this should be the default, probably, as the most logical case. When the line is too big, we wrap. If all attributes can fit into a single line, they stay on the single line, no wrapping. (Default.)
• force - We forcefully wrap if there are more than 1 attribute present, otherwise auto.

When the wrapping is in action, the following properties are in play. If no wrapping happens, they don't play any role.

wrapped_attributes_per_line:

• multiple - Soft wrapping, default. Fit as many attrs per line as allowed.
• single - The first attribute stays on the first line, others are on separate lines.
• single-all - All attributes, including the first one, placed on separate lines. So, every attribute is on a separate line, and the element/tag line has no attributes left.

wrapped_attributes_indent:

1. auto -- Uses wrap_attributes_indent_size, default.
2. aligned -- All attribute lines start aligned with the first attribute. If the first attribute is on a new line ("single-all" mode of wrapped_attributes_per_line), then we use wrap_attributes_indent_size to calculate the indent.

wrapped_attributes_end:

• auto - default
• multiline - the closing > is on the separate line.

Examples

1. DEFAULT case: We soft wrap and try to fit as many attributes per line as possible, but within the line length limit.

wrap_attributes_mode = auto
wrapped_attributes_per_line = multiple
wrapped_attributes_indent = auto
wrapped_attributes_end = auto

1. #1285 case. Very similar to default case, but we align the wrapped attributes to be on the same indent level as the first attribute.

wrap_attributes_mode = auto
wrapped_attributes_per_line = multiple
wrapped_attributes_indent = aligned
wrapped_attributes_end = auto

1. #1262 case. When we wrap, we want one attribute per line, aligned with the first one.

wrap_attributes_mode = auto
wrapped_attributes_per_line = single
wrapped_attributes_indent = aligned
wrapped_attributes_end = auto

1. Current force-expand-multiline case: Force wrapping if there are more than 1 attribute, with one attribute per line, and with multi-line ending, placing the closing > on the new line.

wrap_attributes_mode = force
wrapped_attributes_per_line = single-all
wrapped_attributes_indent = auto
wrapped_attributes_end = multiline