let a stack compute its settings without make

A stack can now ship <name>.env and <name>.sh next to its compose files. The
hook is sourced with the tag helpers available, which is what the computing
.mk files of the catalogue were using make for: 29 of its 44 .mk files only
exist to build variables like the fabio tags.

Converting stack/host/fabio.mk by hand gives byte-identical output for the
route tag, and drops a trailing comma the make version left in the listener
list.

Also: APP_HOST and APP_URI are computed (the tag helpers build on them),
--color controls the escape codes rather than always emitting them, and
make test-portability runs the CLI under busybox ash and dash.

spec/unit/hooks_helper.sh

@@ -0,0 +1,5 @@
+#shellcheck shell=sh
+# Helper: hooks set variables in the caller's scope, which a subshell loses.
+[ -n "${4:-}" ] && eval "$3=\$4"
+myos_stack_hooks "$1" "$2"
+eval "printf '%s\n' \"\${$3:-}\""

spec/unit/hooks_spec.sh

@@ -0,0 +1,82 @@
+#shellcheck shell=sh
+Include lib/str.sh
+Include lib/core.sh
+Include lib/tags.sh
+Include lib/naming.sh
+Include lib/config.sh
+Include lib/hooks.sh
+
+# A stack ships its computed settings as a shell hook, so the catalogue works
+# on a machine without make. These check the hook and the uri it builds on.
+Describe 'lib/hooks.sh'
+  setup() {
+    MYOS_TMP=$(mktemp -d "${TMPDIR:-/tmp}/myos-hook.XXXXXX")
+    MYOS_TMP=$(cd "$MYOS_TMP" && pwd -P)
+    ENV=local; DOMAIN=example.org; USER=tester; HOSTNAME=testhost
+    APP_HOST=demo.example.org; APP_URI=demo.example.org/
+  }
+  cleanup() { rm -rf "$MYOS_TMP"; }
+  BeforeEach setup
+  AfterEach cleanup
+
+  It 'loads plain values from a .env hook'
+    printf 'DEMO_VERSION=1.2.3\n' > "$MYOS_TMP/demo.env"
+    When run source spec/unit/hooks_helper.sh "$MYOS_TMP" demo DEMO_VERSION
+    The output should equal "1.2.3"
+  End
+
+  It 'loads a computed value from a .sh hook'
+    printf 'DEMO_TAGS=$(myos_tagprefix demo 8000)\n' > "$MYOS_TMP/demo.sh"
+    When run source spec/unit/hooks_helper.sh "$MYOS_TMP" demo DEMO_TAGS
+    The output should equal "urlprefix-demo.demo.example.org/*"
+  End
+
+  It 'lets a hook name the service it publishes'
+    printf 'DEMO_SERVICE_8000_NAME=www\nDEMO_TAGS=$(myos_tagprefix demo 8000)\n' > "$MYOS_TMP/demo.sh"
+    When run source spec/unit/hooks_helper.sh "$MYOS_TMP" demo DEMO_TAGS
+    The output should equal "urlprefix-www.demo.example.org/*"
+  End
+
+  It 'lets the environment win over a hook default'
+    printf 'DEMO_VERSION=${DEMO_VERSION:-1.2.3}\n' > "$MYOS_TMP/demo.sh"
+    When run source spec/unit/hooks_helper.sh "$MYOS_TMP" demo DEMO_VERSION 9.9.9
+    The output should equal "9.9.9"
+  End
+
+  It 'is quiet when a stack has no hook'
+    When call myos_stack_hooks "$MYOS_TMP" nothing
+    The status should be success
+    The output should equal ""
+  End
+End
+
+Describe 'lib/naming.sh service uris'
+  BeforeEach 'ENV=local; unset APP_HOST_MULTI_APP APP_HOST_MULTI_USER APP_HOST_MULTI_ENV HOST_LB 2>/dev/null || true'
+
+  It 'serves a host stack on <hostname>.<domain>'
+    When call myos_app_host host aya local fabio example.org sonic
+    The output should equal "sonic.example.org"
+  End
+  It 'adds the bare domain when the host is the load balancer'
+    HOST_LB=true
+    When call myos_app_host host aya local fabio example.org sonic
+    The output should equal "sonic.example.org example.org"
+  End
+  It 'does not prefix a main environment'
+    When call myos_app_host app aya master duniter example.org sonic
+    The output should equal "example.org"
+  End
+  It 'prefixes any other environment'
+    When call myos_app_host app aya staging duniter example.org sonic
+    The output should equal "staging.example.org"
+  End
+  It 'prefixes the user when asked to'
+    APP_HOST_MULTI_USER=true
+    When call myos_app_host app aya master duniter example.org sonic
+    The output should equal "aya.example.org"
+  End
+  It 'builds a uri that ends with a slash'
+    When call myos_app_uri "a.example.org b.example.org"
+    The output should equal "a.example.org/ b.example.org/"
+  End
+End