pull: Add require-static-deltas pull option

For a production release repository, most OS vendors would want
to just always use static deltas.  Add the ability for the pulls to
require it.

(I think I'll also add a summary key for this actually in addition,
 so the repo manager can force it too)

tests/pull-test.sh

@@ -106,12 +106,18 @@ cd ..
 rm main-files -rf
 # Generate delta that we'll use
 ${CMD_PREFIX} ostree --repo=ostree-srv/gnomerepo static-delta generate main
+prev_rev=$(ostree --repo=ostree-srv/gnomerepo rev-parse main^)
+ostree --repo=ostree-srv/gnomerepo summary -u
 
 cd ${test_tmpdir}
-${CMD_PREFIX} ostree --repo=repo pull origin main
+repo_init
+${CMD_PREFIX} ostree --repo=repo pull origin main@${prev_rev}
+${CMD_PREFIX} ostree --repo=repo pull --require-static-deltas origin main
 ${CMD_PREFIX} ostree --repo=repo fsck
 
 cd ${test_tmpdir}
+repo_init
+${CMD_PREFIX} ostree --repo=repo pull origin main@${prev_rev}
 ${CMD_PREFIX} ostree --repo=repo pull --disable-static-deltas origin main
 ${CMD_PREFIX} ostree --repo=repo fsck
 
@@ -124,6 +130,16 @@ assert_not_has_file baz/saucer
 
 echo "ok static delta"
 
+cd ${test_tmpdir}
+rm ostree-srv/gnomerepo/deltas -rf
+ostree --repo=ostree-srv/gnomerepo summary -u
+repo_init
+if ${CMD_PREFIX} ostree --repo=repo pull --require-static-deltas origin main 2>err.txt; then
+    assert_not_reached "--require-static-deltas unexpectedly succeeded"
+fi
+assert_file_has_content err.txt "deltas required, but none found"
+${CMD_PREFIX} ostree --repo=repo fsck
+
 cd ${test_tmpdir}
 rm main-files -rf
 ${CMD_PREFIX} ostree --repo=ostree-srv/gnomerepo checkout main main-files
@@ -134,6 +150,7 @@ cd ..
 rm main-files -rf
 # Generate new delta that we'll use
 ${CMD_PREFIX} ostree --repo=ostree-srv/gnomerepo static-delta generate --inline main
+ostree --repo=ostree-srv/gnomerepo summary -u
 
 cd ${test_tmpdir}
 ${CMD_PREFIX} ostree --repo=repo pull origin main
@@ -157,6 +174,7 @@ ${CMD_PREFIX} ostree --repo=${test_tmpdir}/ostree-srv/gnomerepo commit -b main -
 cd ..
 rm main-files -rf
 ${CMD_PREFIX} ostree --repo=ostree-srv/gnomerepo static-delta generate main
+ostree --repo=ostree-srv/gnomerepo summary -u
 
 cd ${test_tmpdir}
 ${CMD_PREFIX} ostree --repo=repo pull origin main