tests: add tests for setup-env.sh

- tests use a shell-script harness and test all Spack commands that
  require special shell support.

- tests work in bash, zsh, and dash

- run setup-env.sh tests on macos and linux builds.
  - we run them on macos and linux

.travis.yml

@@ -50,24 +50,6 @@ jobs:
       os: linux
       language: python
       env: [ TEST_SUITE=unit, COVERAGE=true ]
-      addons:
-        apt:
-          packages:
-          - cmake
-          - gfortran
-          - graphviz
-          - gnupg2
-          - kcov
-          - mercurial
-          - ninja-build
-          - perl
-          - perl-base
-          - realpath
-          - patchelf
-          - r-base
-          - r-base-core
-          - r-base-dev
-
     - python: '3.7'
       sudo: required
       os: linux
@@ -159,6 +141,7 @@ addons:
       - r-base
       - r-base-core
       - r-base-dev
+      - zsh
   # for Mac builds, we use Homebrew
   homebrew:
     packages:
@@ -166,6 +149,8 @@ addons:
       - gcc
       - gnupg2
       - ccache
+      - dash
+      - kcov
     update: true
 
 # ~/.ccache needs to be cached directly as Travis is not taking care of it
@@ -223,11 +208,13 @@ script:
 
 after_success:
   - ccache -s
-  - if [[ "$TEST_SUITE" == "unit" || "$TEST_SUITE" == "build" ]]; then
-        codecov --env PYTHON_VERSION
-                --required
-                --flags "${TEST_SUITE}${TRAVIS_OS_NAME}";
-    fi
+  - case "$TEST_SUITE" in
+        unit)
+            codecov --env PYTHON_VERSION
+                    --required
+                    --flags "${TEST_SUITE}${TRAVIS_OS_NAME}";
+            ;;
+    esac
 
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