I thought I cannot get void-variable issue for declared dynamically bound
variables.
Your assumption is wrong. Dynamically bound (or “special” in other Lisps)
variables can be unbound. In fact if you declare it like (taken from
haskell-indentation.el):
(defvar implicit-layout-active) ;; is "off-side" rule active?
You are declaring variable implicit-layout-active whiteout setting its
value. We can read about it in doc-string:
defvar is a special form in ‘C source code’.
(defvar SYMBOL &optional INITVALUE DOCSTRING)
…
The optional argument INITVALUE is evaluated, and used to set SYMBOL, only
if SYMBOL's value is void. If SYMBOL is buffer-local, its default value
is what is set; buffer-local values are not affected. If INITVALUE is
missing, SYMBOL's value is not set.
This answers your question: you've defined a dynamic variable and have not
set its value. Obviously your code doesn't let bind it in some case and
thus you get the error.
As for your comment that (defvar implicit-layout-active) is the same as
(defvar implicit-layout-active nil) — you should check better. A few
things to consider:
When your test suite evaluates (require 'haskell-indentation) which
module does it load: where you supply default value or “older” byte
compiled version installed via package manager?
Also note that defvar only sets value if variable is currently unbound
(this is not actual issue in your case, just a word of caution).
Having said all this I can evaluate
(defvar implicit-layout-active nil)
and the dynamic variable is bound:
(boundp implicit-layout-active) ⇒ t
Now if I run your test case I get:
F haskell-indentation-check-23
should not fail when seeing comments
(ert-test-failed
((should
(equal
(cons
(list ... ...)
(haskell-indentation-find-indentations))
current))
:form
(equal
((3 2))
((3 2)
0))
:value nil :explanation
(proper-lists-of-different-length 1 2
((3 2))
((3 2)
0)
first-mismatch-at 1)))
