select() is not resolved when used in a list comprehension or dict.values() #8171
Closed as not planned
Description
Description of the problem / feature request:
If a dictionary or list contains a select(), and that dict/list is used in a list comprehension (i.e. when constructing a string of all keys in the dict), the select() is not resolved.
The select() is also not resolved when accessing the values in a dict using dict.values().
Using a for loop to construct a string in a macro instead of a list comprehension expands the select() as expected. However, constructing a list in a macro does not expand the select().
Bugs: what's the simplest, easiest way to reproduce this bug? Please provide a minimal example if possible.
test.bzl:
# select() resolved
def test_stringify(d):
s = ""
for key in d:
s += d[key] + "\n"
return s
# select() NOT resolved
def test_listify(d):
l = []
for key in d:
l.append(d[key])
return l
BUILD.bazel:
load("//:test.bzl", "test_stringify", "test_listify")
d = {
"1": "dict_constant",
"2": select({
"//conditions:default": "dict_selected"
})
}
key_in_variable = "2"
l = [
"list_constant",
select({
"//conditions:default": "list_selected"
})
]
genrule (
name = "test",
outs = ["test"],
cmd = "echo '" +
"#### Select() is *NOT* expanded by these incantations:\n" +
"\n".join([d[x] for x in d]) + "\n\n" +
"\n".join(d.values()) + "\n\n" +
"{}".format(d.values()) + "\n\n" +
"\n".join([d[k] for (k, x) in zip(d.keys(), d.values())]) + "\n\n" +
"\n".join(l) + "\n\n" +
"\n".join([l[i] for i in range(len(l))]) + "\n\n" +
str(test_listify(d)) + "\n\n" +
"#### Select() *IS* expanded by these incantations:\n" +
l[1] + "\n\n" +
d["2"] + "\n\n" +
d[key_in_variable] + "\n\n" +
test_stringify(d) +
"' > $(location test)"
)
$ bazel build //:test && cat bazel-genfiles/test
#### Select() is *NOT* expanded by these incantations:
dict_constant
select({"//conditions:default": "dict_selected"})
dict_constant
select({"//conditions:default": "dict_selected"})
["dict_constant", select({"//conditions:default": "dict_selected"})]
dict_constant
select({"//conditions:default": "dict_selected"})
list_constant
select({"//conditions:default": "list_selected"})
list_constant
select({"//conditions:default": "list_selected"})
["dict_constant", select({"//conditions:default": "dict_selected"})]
#### Select() *IS* expanded by these incantations:
list_selected
dict_selected
dict_selected
dict_constant
dict_selected
What operating system are you running Bazel on?
Ubuntu 18.04
What's the output of bazel info release?
release 0.22.0