diff --git a/plugins/python-build/bin/python-build b/plugins/python-build/bin/python-build
index c2d6b169..09800c06 100755
--- a/plugins/python-build/bin/python-build
+++ b/plugins/python-build/bin/python-build
@@ -134,7 +134,11 @@ can_use_homebrew() {
   is_mac && command -v brew &>/dev/null && return 0
   # In Linux, if Pyenv itself is installed with Homebrew,
   # we assume the user wants to take dependencies from there as well by default
-  command -v brew &>/dev/null && [[ $(abs_dirname "${BASH_SOURCE}") == "$(abs_dirname "$(brew --prefix)")"/* ]] &&
+  local brew_prefix
+  command -v brew &>/dev/null && \
+    # tests can have non-functional `brew' stub aliased to `false'
+    brew_prefix="$(brew --prefix)" && 
+    [[ $(abs_dirname "${BASH_SOURCE}") == "$(abs_dirname "${brew_prefix}")"/* ]] &&
   { lock_in homebrew; return 0; }
   
   # do not check the same stuff multiple times