Convert the empty-stratum test into a yarn

We will use MorphologyLoader.load_from_file() to load morphologies
from a temporary file, so the output will be unpredictable. That
will break this test, so we may as well convert it into a yarn
to fix it.

5 files changed, 37 insertions, 38 deletions

diff --git a/tests.build/empty-stratum.exit b/tests.build/empty-stratum.exit
deleted file mode 100644
index d00491fd..00000000
--- a/tests.build/empty-stratum.exit
+++ /dev/null
@@ -1 +0,0 @@
-1
diff --git a/tests.build/empty-stratum.script b/tests.build/empty-stratum.script
deleted file mode 100755
index 19c36558..00000000
--- a/tests.build/empty-stratum.script
+++ /dev/null
@@ -1,36 +0,0 @@
-#!/bin/sh
-#
-# Copyright (C) 2013-2014  Codethink Limited
-#
-# This program is free software; you can redistribute it and/or modify
-# it under the terms of the GNU General Public License as published by
-# the Free Software Foundation; version 2 of the License.
-#
-# This program is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU General Public License for more details.
-#
-# You should have received a copy of the GNU General Public License along
-# with this program; if not, write to the Free Software Foundation, Inc.,
-# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
-
-set -eu
-
-morphsrepo="$DATADIR/morphs-repo"
-cd "$morphsrepo"
-
-git checkout --quiet -b empty-stratum
-
-# Create empty stratum to test S4585
-cat <<EOF > hello-stratum.morph
-name: hello-stratum
-kind: stratum
-EOF
-sed -i 's/master/empty-stratum/' hello-system.morph
-git add hello-stratum.morph hello-system.morph
-
-git commit --quiet -m "add empty stratum"
-
-"$SRCDIR/scripts/test-morph" build-morphology \
-    test:morphs-repo empty-stratum hello-system
diff --git a/tests.build/empty-stratum.stderr b/tests.build/empty-stratum.stderr
deleted file mode 100644
index 6a4ecb05..00000000
--- a/tests.build/empty-stratum.stderr
+++ /dev/null
@@ -1 +0,0 @@
-ERROR: Stratum hello-stratum has no chunks in string
diff --git a/yarns/building.yarn b/yarns/building.yarn
index 90daf069..b5e46b73 100644
--- a/yarns/building.yarn
+++ b/yarns/building.yarn
@@ -101,3 +101,14 @@ repos cached locally.
     AND the distbuild worker is terminated
     AND the communal cache server is terminated
     AND the git server is shut down
+
+Empty strata don't build
+------------------------
+
+    SCENARIO empty-strata
+    GIVEN a workspace
+    AND a git server
+    WHEN the user checks out the system branch called empty-stratum
+    AND the user attempts to build the system systems/empty-stratum-system.morph in branch empty-stratum
+    THEN morph failed
+    FINALLY the git server is shut down
diff --git a/yarns/implementations.yarn b/yarns/implementations.yarn
index 8b43286f..2557e2e5 100644
--- a/yarns/implementations.yarn
+++ b/yarns/implementations.yarn
@@ -336,6 +336,32 @@ another to hold a chunk.
     git commit -m Initial.
     git tag -a "test-tag" -m "Tagging test-tag"
 
+    # A new branch is created here as the presence of an empty stratum will
+    # break any morph commands which load all definitions in the repository.
+    git checkout -b empty-stratum
+
+    install -m644 -D /dev/stdin << EOF "systems/empty-stratum-system.morph"
+    name: empty-stratum-system
+    kind: system
+    arch: $arch
+    strata:
+    - name: build-essential
+      morph: strata/build-essential.morph
+    - name: core
+      morph: strata/core.morph
+    - name: empty
+      morph: strata/empty.morph
+    EOF
+
+    install -m644 -D /dev/stdin << EOF "strata/empty.morph"
+    name: empty
+    kind: stratum
+    EOF
+
+    git add .
+    git commit -m 'Add an empty stratum'
+    git checkout master
+
     # Start a git daemon to serve our git repositories
     port_file="$DATADIR/git-daemon-port"
     pid_file="$DATADIR/git-daemon-pid"