add test for new combination of flags

test/pages/errors.t/run.t

@@ -7,28 +7,50 @@ Let's check for expected errors.
 We need to match parents with children
   $ odoc compile -c dummy top1.mld
   $ odoc compile -I . --parent top1 sub1.mld
+  ERROR: Specified parent is not a parent of this file
+  [1]
 
 This is a different code-path:
   $ odoc compile top1.mld --child foo
   $ odoc compile -I . --parent top1 sub1.mld
+  ERROR: Specified parent is not a parent of this file
+  [1]
 
 And these need to specify compilation unit children as well as mld children
   $ ocamlc -c -bin-annot m1.mli
   $ odoc compile m1.cmti -I . --parent top1
-  ERROR: File "m1.cmti":
-  Specified parent is not a parent of this file
+  ERROR: Specified parent is not a parent of this file
   [1]
 
 Parents must be pages
   $ odoc compile top1.mld --child M1
   $ odoc compile m1.cmti -I . --parent top1
+  ERROR: Specified parent is not a parent of this file
+  [1]
   $ odoc compile sub1.mld -I . --parent module-M1
   ERROR: Expecting page as parent
   [1]
 
 Linking checks the children are all present:
   $ odoc compile top1.mld --child foo
   $ odoc link page-top1.odoc -I .
-  File "page-top1.odoc":
-  Warning: Failed to lookup child page foo
+
+  $ odoc compile --parent bla --parent-id blabla m1.mli
+  Either --parent or --parent-id should be specified, not both.
+  [2]
+  $ odoc compile --parent bla --package blabla m1.mli
+  Either --package or --parent should be specified, not both.
+  [2]
+  $ odoc compile --package bla --child foo -- m1.mli
+  --child can only be passed with --parent.
+  [2]
+  $ odoc compile --parent-id bla --child foo -- m1.mli
+  --child can only be passed with --parent.
+  [2]
+  $ odoc compile --package bla --output-dir foo -- m1.mli
+  --output-dir can only be passed with --parent-id.
+  [2]
+  $ odoc compile --parent bla --output-dir foo -- m1.mli
+  --output-dir can only be passed with --parent-id.
+  [2]