Add a test for promoting from a nonexistent subdir

Author: cpitclaudel

Diff for: test/blackbox-tests/dune.inc

@@ -1894,6 +1894,17 @@
    test-cases/no-name-field
    (progn (run dune-cram run run.t) (diff? run.t run.t.corrected)))))
 
+(rule
+ (alias nonexistent-subdir)
+ (deps
+  (package dune)
+  (source_tree test-cases/nonexistent-subdir)
+  (alias test-deps))
+ (action
+  (chdir
+   test-cases/nonexistent-subdir
+   (progn (run dune-cram run run.t) (diff? run.t run.t.corrected)))))
+
 (rule
  (alias null-dep)
  (deps (package dune) (source_tree test-cases/null-dep) (alias test-deps))
@@ -3197,6 +3208,7 @@
   (alias no-infer)
   (alias no-installable-mode)
   (alias no-name-field)
+  (alias nonexistent-subdir)
   (alias null-dep)
   (alias ocaml-config-macro)
   (alias ocaml-syntax)
@@ -3479,6 +3491,7 @@
   (alias no-infer)
   (alias no-installable-mode)
   (alias no-name-field)
+  (alias nonexistent-subdir)
   (alias null-dep)
   (alias ocaml-config-macro)
   (alias ocaml-syntax)

Diff for: test/blackbox-tests/test-cases/nonexistent-subdir/dune

@@ -0,0 +1,4 @@
+(subdir "x"
+ (rule
+ (mode (promote (until-clean)))
+ (action (with-stdout-to y (echo "z")))))

Diff for: test/blackbox-tests/test-cases/nonexistent-subdir/dune-project

@@ -0,0 +1 @@
+(lang dune 2.5)

Diff for: test/blackbox-tests/test-cases/nonexistent-subdir/run.t

@@ -0,0 +1,4 @@
+Check that promoting from a nonexistent subdir doesn't cause crashes.
+  $ dune build x/y
+  $ cat x/y
+  z