Env variables don't work in if-else-endif templates

[AtomToast]

Describe the bug

Similarly to #486, trying to use env variables in {% if env.EXAMPLE == "example" %} with the default template processor does not work.

To reproduce

Can this be reproduced with the yadm/testbed docker image: Yes script.gz

Steps to reproduce the behavior:

1. export TEST=testing

2. cat << EOF > test.txt##template         
   {% if env.TEST == "testing" %}
   success
   {% else %}
   fail
   {% endif %}
   EOF

3. yadm add test.txt##template
4. cat test.txt

Expected behavior

The file should contain success, however instead it uses the fail branch.

Environment

• Operating system: Arch Linux
• Version yadm: 3.2.2
• Version Git: 2.45.1

Additional context

From a brief look at the code, it seems that this is actually just not implemented right now?

[rasa]

@AtomToast It's in the code at https://github.com/TheLocehiliosan/yadm/blob/0a5e7aa353621bd28a289a50c0f0d61462b18c76/yadm#L429 and the test to confirm it works is at https://github.com/TheLocehiliosan/yadm/blob/0a5e7aa353621bd28a289a50c0f0d61462b18c76/test/test_unit_template_default.py#L246 Do other vars get substituted correctly?

[rasa]

On my system, env.HOME substitutes correctly. Ubuntu 24.04 and

$ yadm version
bash version 5.2.21(1)-release
 git version 2.43.0
yadm version 3.2.2
$ awk --version| head -n 1
GNU Awk 5.2.1, API 3.2, PMA Avon 8-g1, (GNU MPFR 4.2.1, GNU MP 6.3.0)

[AtomToast]

Please correct me if I'm wrong but to me this is again only the variable substitution part of the code. This works for me. What doesn't work for me are if blocks. As per https://yadm.io/docs/templates, in the if-else-endif section.

[rasa]

@AtomToast Good point. I haven't tested it, but the env. logic is the same as the other yadm. so I am really surprised it's not working. See https://github.com/TheLocehiliosan/yadm/blob/0a5e7aa353621bd28a289a50c0f0d61462b18c76/yadm#L426-L431

[AtomToast]

For me this is 100% reproducable.

The code you linked is part of the replaces_vars() function, which does not seem to be called in the conditions() function. There all I can see is this https://github.com/TheLocehiliosan/yadm/blob/0a5e7aa353621bd28a289a50c0f0d61462b18c76/yadm#L441 which I believe is the yadm. part of the logic? There is no EVIRON[label] call

[rasa]

@AtomToast You are correct. Just below https://github.com/TheLocehiliosan/yadm/blob/0a5e7aa353621bd28a289a50c0f0d61462b18c76/yadm#L439-L444 we need to add

    for (label in ENVIRON) {
       value = ENVIRON[label] 
       pattern = sprintf("%s%s|", pattern, condition_helper(label, value)); 
    }

[AtomToast]

That alone seems to not have done it for me. Is there perhaps something else missing?

[github-actions[bot]]

This issue has been labeled as stale because it has been open 60 days with no activity. Remove stale label or comment or this will be closed in 7 days.

[AtomToast]

@rasa Hey, sorry for the bother but the bot marked this as stale. Have you managed to make this work?

[rasa]

@AtomToast No sorry, I haven't. Hopefully @TheLocehiliosan can un-stale this, as I can't.

[soraxas]

@AtomToast Does these changes fixes for you?

https://github.com/soraxas/yadm/pull/1/files

diff --git a/yadm b/yadm
index bfbcd81..a61f37f 100755
--- a/yadm
+++ b/yadm
@@ -432,20 +432,23 @@ function replace_vars() {
 }
 function condition_helper(label, value) {
   gsub(/[\\.^$(){}\[\]|*+?]/, "\\\\&", value)
-  return sprintf("yadm\\.%s" blank "*==" blank "*\"%s\"", label, value)
+  return sprintf("%s" blank "*==" blank "*\"%s\"", label, value)
 }
 function conditions() {
   pattern = ifs blank "+("
+  for (label in ENVIRON) {
+    pattern = sprintf("%s%s|", pattern, condition_helper("env\\." label, ENVIRON[label]));
+  }
   for (label in c) {
     if (label != "class") {
       value = c[label]
-      pattern = sprintf("%s%s|", pattern, condition_helper(label, value));
+      pattern = sprintf("%s%s|", pattern, condition_helper("yadm\\." label, value));
     }
   }
   split(classes, cls_array, "\n")
   for (idx in cls_array) {
     value = cls_array[idx]
-    pattern = sprintf("%s%s|", pattern, condition_helper("class", value));
+    pattern = sprintf("%s%s|", pattern, condition_helper("yadm\\." "class", value));
   }
   sub(/\|$/, ")" blank "*%}$", pattern)
   return pattern

(I shall note that the current template replacement seems pretty inefficient as it needs to loop-through all class/envars everytime; though its still "fast enough" and the operation would be rare)

[AtomToast]

@soraxas Unfortunately no :/ I tried it with both the test case from the original post and some additional ones. I also tried cloning your entire repo which seems to have some additional changes.

Does it work for you with those changes?

[soraxas]

Yes it does works for me

Have you point your $PATH to your cloned repo (or maybe it's still using the older yadm)?

[AtomToast]

I first directly edited the yadm binary in /bin. When using the cloned repo I called yadm with an absolute path. For some reason, now having retested it on my laptop, it seems to work now. Not sure what I did wrong on my other PC or if there was some other variable