Clojurians Log v2
ghostwheel 2018-07-16
question for @clojurians.net or whoever
step 1 of getting started
add the artifact to your build configuration
in my case, a figwheel project
im used to adding deps to the top level :dependencies in my project
am i meant to be adding ghostwheel to my :dev build profile deps instead?
No. You're replacing your defns with >defn. If you were to run a build without ghostwheel as a dependency, those macros would be undefined. Ghostwheel does a good job of compiling away to nothing in a production build. Just make sure that your :ghostwheel configuration is only applied to your dev build.
Additional question: I can't seem to get the syntax correct for a function with no arguments?
(>defn navigation-menu
[]
[? => vector?]
[:nav#navigation
[:ul
[:li [:i.fas.fa-bars]]
[:li.active "Games"]
[:li "Explore"]
[:li "Leaderboards"]
[:li "Contact"]
[:li "Login"]]])
I thought this is what I'd want but it fails the >defn spec..
@samueldev I guess that first ? on the arg declaration shouldn't be there
have you tried just [=> vector?]?
@wilkerlucio that did it 🙂 thank you!
Now I'm getting some interesting (confusing) feedback from (g/check) on my namespace
Output:
(no details are present in the outputted log denoting that there's some kind of spec check failure)
(ns website.components
#:ghostwheel.core{:check true
:num-tests 10
:outstrument true}
(:require [ghostwheel.core :as g :refer [>defn => |]]))
(>defn navigation-menu
"website nav"
[]
[=> vector?]
[:nav#navigation
[:ul
[:li [:i.fas.fa-bars]]
[:li.active "Games"]
[:li "Explore"]
[:li "Leaderboards"]
[:li "Contact"]
[:li "Login"]]])
(js/console.log (navigation-menu))
(g/check)
@samueldev What version are you running?
0.2.3
@samueldev Hey, Sam, please confirm that it's the final 0.2.3 version and not a "-SNAPSHOT". I'll look into it in the meantime. On first sight some keywords look invalid, but not sure if that's related – I don't think you can have . in a keyword.
that's the reagent shorthand syntax for classes on a dom element
and it is the final version, yup 🙂
Got it, will get back to you a bit later.
@samueldev I can't reproduce this here, everything checks out fine with 0.2.3, so let's make sure this isn't a stale build/cache issue first. Clean your build, remove .shadow-cljs if you're using it, remove ~/.m2/repository/gnl and try again.
On a side note – I'd recommend against outstrumenting the whole namespace when you're also checking it. This is a bit of a belt and suspenders situation and most likely you really only need one.
I was under the impression that ::g/check just enabled generative testing; not any kind of runtime call-checking. Looking at the docs, I can't find anywhere that outlines exactly what ::g/check does. Why would you recommend against using both? Does ::g/check report contract violations during runtime?
g/check doesn't do anything at runtime (differentiating here between runtime and test time). It's the recommended approach, because you get proper code coverage, a much higher likelihood of catching edge cases, and no runtime performance penalty. I don't really use g/outstrument or g/instrument, but I know people do and it was easy to implement, that's why it's in there. But when they are used, I'd say it makes more sense to use them on a single function basis.
But point taken on that it's not exactly clear from the documentation what g/check does under the hood, precisely. I'll add it to the readme, but the tl;dr is that it generates the test code and is required for the additional checks that (g/check) does.
And regarding the . in keywords – apparently we were both sort of right. It violates the specification as far as I understand it, but the compiler's fine with it and changing that would break too much existing code, so I guess it's fine and likely to remain so. A bit like keywords starting with a number.
Everyone – if you have 2 seconds, please vote here for your preferred gspec operators if you haven't yet: https://clojurians.slack.com/archives/CBGSAMBPW/p1531436074000224 (message is pinned to the channel) I'm not taking anything out, just curious how Clojurians feel about this in general.