yarns: add a scenario for checking out a chunk

2 files changed, 30 insertions, 0 deletions

diff --git a/yarns/branches-workspaces.yarn b/yarns/branches-workspaces.yarn
index bfcb9e66..3af362a1 100644
--- a/yarns/branches-workspaces.yarn
+++ b/yarns/branches-workspaces.yarn
@@ -58,6 +58,15 @@ Checking out a system branch should fail, if the branch doesn't exist.
     WHEN        morph attempts to check out system branch foo
     THEN        morph failed
 
+Checking out a system branch should also fail if the repository does
+not contain any system morphologies.
+
+    SCENARIO    checking out a system branch with no systems
+    GIVEN       a workspace
+    AND         a git server
+    WHEN        morph attempts to check out a repository with no systems
+    THEN        morph failed
+
 We can, instead, create a new system branch, off master.
 
     SCENARIO    branch off master
@@ -78,6 +87,15 @@ to check for that locally.
     AND         creating system branch bar, based on foo
     THEN        the system branch bar is checked out
 
+Similarly, attempting to branch a system branch should fail if the
+repository does not contain any system morphologies.
+
+    SCENARIO    checking out a system branch with no systems
+    GIVEN       a workspace
+    AND         a git server
+    WHEN        morph attempts to branch a repository with no systems
+    THEN        morph failed
+
 Query commands in workspaces
 ----------------------------
 
diff --git a/yarns/implementations.yarn b/yarns/implementations.yarn
index dc5f1f54..7f9281ac 100644
--- a/yarns/implementations.yarn
+++ b/yarns/implementations.yarn
@@ -126,6 +126,12 @@ Attempt to check out a system branch, and remember if it failed.
     cd "$DATADIR/workspace"
     attempt_morph checkout test:morphs "$MATCH_1"
 
+Attempt to check out a system branch from a root that has no systems.
+
+    IMPLEMENTS WHEN morph attempts to check out a repository with no systems
+    cd "$DATADIR/workspace"
+    attempt_morph checkout test:test-chunk master
+
 We also need to verify that a system branch has been checked out.
 
     IMPLEMENTS THEN the system branch (\S+) is checked out
@@ -145,6 +151,12 @@ We can create a new branch, off another system branch.
     cd "$DATADIR/workspace"
     run_morph branch test:morphs "$MATCH_1" "$MATCH_2"
 
+Attempt to branch a system branch from a root that had no systems.
+
+    IMPLEMENTS WHEN morph attempts to branch a repository with no systems
+    cd "$DATADIR/workspace"
+    attempt_morph branch test:test-chunk foo
+
 Pushing all changes in a system branch checkout to the git server.
 
     IMPLEMENTS WHEN pushing system branch (\S+) to git server