templater: make strings in template expressions be "string-escape"-ed correctly
Changeset
64b4f0cd7336 (released with 2.8.1) fixed "recursively
evaluate string literals as templates" problem (
issue4102) by moving
the location of "string-escape"-ing from "tokenizer()" to
"compiletemplate()".
But some parts in template expressions below are not processed by
"compiletemplate()", and it may cause unexpected result.
- 'expr' of 'if(expr, then, else)'
- 'expr's of 'ifeq(expr, expr, then, else)'
- 'sep' of 'join(list, sep)'
- 'text' and 'style' of 'rstdoc(text, style)'
- 'text' and 'chars' of 'strip(text, chars)'
- 'pat' and 'repl' of 'sub(pat, repl, expr)'
For example, '\n' of "{join(extras, '\n')}" is not "string-escape"-ed
and treated as a literal '\n'. This breaks "Display the contents of
the 'extra' field, one per line" example in "hg help templates".
Just "string-escape"-ing on each parts above may not work correctly,
because inside expression of nested ones already applies
"string-escape" on string literals. For example:
- "{join(files, '\n')}" doesn't return "string-escape"-ed string, but
- "{join(files, if(branch, '\n', '\n'))}" does
To fix this problem, this patch does:
- introduce "rawstring" token and "runrawstring" method to handle
strings not to be "string-escape"-ed correctly, and
- make "runstring" method return "string-escape"-ed string, and
delay "string-escape"-ing until evaluation
This patch invokes "compiletemplate()" with "strtoken=exp[0]" in
"gettemplate()", because "exp[1]" is not yet evaluated. This code path
is tested via mapping ("expr % '{template}'").
In the other hand, this patch invokes it with "strtoken='rawstring'"
in "_evalifliteral()", because "t" is the result of "arg" evaluation
and it should be "string-escape"-ed if "arg" is "string" expression.
This patch doesn't test "string-escape"-ing on 'expr' of 'if(expr,
then, else)', because it doesn't affect the result.
templater: apply "stringify()" on sub expression to get string correctly
Templating syntax allows nested expression to be specified as parts
below, but they are evaluated as a generator and don't work correctly.
- 'sep' of 'join(list, sep)'
- 'text' and 'chars' of 'strip(text, chars)'
In the former case, 'sep' returns expected string only for the first
separation, and empty one for the second or later, because the
generator has only one element.
In the latter case, templating is aborted by exception, because the
generator doesn't have 'strip()' method (as 'text') and can't be
passed as the argument to 'str.strip()' (as 'chars').
This patch applies "stringify()" on these sub expression to get string
correctly.