Partials useParams fix to allow square bracket properties

[joelpurra]

Was trying to use doT 1.0.0+ partials with parameters, but ran into problems trying to pass in something like myJsonObject["property-with-dashes"]. The original useParams looked weird (and it's undocumented), so rewrote the parameter part, and fixed some related problems at the same time.

• Square bracket object properties, it['bar'], it['bar baz']
• Arrays with index, it[1]
• Square bracket object properties with variables it[myvar] (untested)
• Deep object addressing, it['bar baz'].qux[1]
• Uppercase or mixed case variable names

Commited new Mocha tests separately.

Usage example

{{##def.tmp:input:<div>{{!input.foo}}</div>#}}

{{#def.tmp:myJsonObject["property-with-dashes"]}}

If this patch doesn't get accepted, you can still use it by changing the settings:

doT.templateSettings.useParams = /(^|[^\w$])def(?:\.|\[[\'\"])([\w$\.]+)(?:[\'\"]\])?\s*\:\s*((?:[_a-z$][\w$]+)(?:\.[_a-z$][\w$]+|\[(?:(?:[_a-z$][\w$]+)|\d+|(["'])(?![^\\]\4).+\4)\])*)\s*$/i;

---

Appendices

Regexp with test data. Use for example regexpal.com with Case insensitive (i) and ^$ match at line breaks (m).

Original useParams regex

(^|[^\w$])def(?:\.|\[[\'\"])([\w$\.]+)(?:[\'\"]\])?\s*\:\s*([\w$\.]+|\"[^\"]+\"|\'[^\']+\'|\{[^\}]+\})

Naïve fix, matches too many rows

(^|[^\w$])def(?:\.|\[[\'\"])([\w$\.]+)(?:[\'\"]\])?\s*\:\s*((?:[\w$\.]+|\[[^\]]+\])+)

Better fix

(^|[^\w$])def(?:\.|\[[\'\"])([\w$\.]+)(?:[\'\"]\])?\s*\:\s*((?:[_a-z$][\w$]+)(?:\.[_a-z$][\w$]+|\[(?:(?:[_a-z$][\w$]+)|\d+|(["'])(?![^\\]\4).+\4)\])*)\s*$

Test data

// This block should match the entire row for all rows
def.fnname:param
#def.fnname:param
def.fnname:param.foo
def.fnname:param['foo']
def.fnname:param["foo"]
def.fnname:param['foo bar']
def.fnname:param["foo bar"]
def.fnname:param[01234]
def.fnname:param[varname]
def.fnname:param.foo.qux["quux"][43210]
def.fnname:param['foo'].qux["quux"][43210]
def.fnname:param["foo"].qux["quux"][43210]
def.fnname:param['foo bar'].qux["quux"][43210]
def.fnname:param["foo bar"].qux["quux"][43210]
def.fnname:param[01234].qux["quux"][43210]
def.fnname:param[varname].qux["quux"][43210]
def.fnname:param[varname].qux["quåäö+ππππux"][43210]
def.fnname:Param
def.fnname:Param.Foo
def.fnname:Param['Foo Bar']


// This block should not match any part of any rows
def.fnname:param'foo'
def.fnname:param"foo bar"
def.fnname:param.01234
def.fnname:param.foo.qux."quux".43210
def.fnname:param'foo bar'.qux"quux".43210
def.fnname:param.
#def.fnname:param.
def.fnname:param.foo.
def.fnname:param['foo bar'].