use stack build --dry-run to check if deps are installed

The system might have stack installed, so stack --version would succeed,
but need stack setup to be run to get a working ghc.

This will fail if stack is not installed, or if stack setup needs to be
run. It does not fail when haskell libraries are not installed, but
stack build will install those anyway, so that's ok.

1 files changed, 2 insertions, 3 deletions

diff --git a/src/Propellor/Bootstrap.hs b/src/Propellor/Bootstrap.hs
index baf36e49..d3d0264b 100644
--- a/src/Propellor/Bootstrap.hs
+++ b/src/Propellor/Bootstrap.hs
@@ -86,13 +86,12 @@ buildCommand bs = intercalate " && " (go (getBuilder bs))
 		, "ln -sf $(stack path --dist-dir)/build/propellor-config propellor"
 		]
 
--- Run cabal configure to check if all dependencies are installed;
--- if not, run the depsCommand.
+-- Check if all dependencies are installed; if not, run the depsCommand.
 checkDepsCommand :: Bootstrapper -> Maybe System -> ShellCommand
 checkDepsCommand bs sys = go (getBuilder bs)
   where
 	go Cabal = "if ! cabal configure >/dev/null 2>&1; then " ++ depsCommand bs sys ++ "; fi"
-	go Stack = "if ! stack --version >/dev/null 2>&1; then " ++ depsCommand bs sys ++ "; fi"
+	go Stack = "if ! stack build --dry-run >/dev/null 2>&1; then " ++ depsCommand bs sys ++ "; fi"
 
 -- Install build dependencies of propellor, using the specified
 -- Bootstrapper.