test(cram): partial promotions when script exits

Signed-off-by: Ali Caglayan <[email protected]>

Author: Alizter

test/blackbox-tests/test-cases/cram/partial-promotion-on-error.t

@@ -0,0 +1,41 @@
+Test that cram tests with unreachable commands can still partially promote
+output from commands that executed successfully.
+
+  $ cat > dune-project <<EOF
+  > (lang dune 3.21)
+  > EOF
+
+Create a test with some successful commands, then an exit, then unreachable
+commands:
+
+  $ cat > test.t <<EOF
+  >   $ echo "First command"
+  >   $ echo "Second command"
+  >   $ exit 1
+  >   $ echo "This will never execute"
+  >   $ echo "Neither will this"
+  > EOF
+
+The test should fail but still capture output from executed commands:
+  $ dune runtest
+  File "test.t", line 1, characters 0-0:
+  Error: Files _build/default/test.t and _build/default/test.t.corrected
+  differ.
+  [1]
+  $ dune promote
+  Promoting _build/default/test.t.corrected to test.t.
+
+After promotion, the test file should have output from successful commands and
+UNREACHABLE markers for the rest:
+  $ cat test.t
+    $ echo "First command"
+    First command
+    $ echo "Second command"
+    Second command
+    $ exit 1
+    ***** UNREACHABLE *****
+    $ echo "This will never execute"
+    ***** UNREACHABLE *****
+    $ echo "Neither will this"
+    ***** UNREACHABLE *****
+