add tests for forges not supporting organization style repo

Signed-off-by: teague hansen <thanse23@asu.edu>

test/blackbox-tests/test-cases/source-stanza.t

@@ -21,7 +21,7 @@ Test a generated 'github' user repo
 
 Test a generated 'gitlab' user repo
 
-  $ sed -i '4c\(source (gitlab user/repo))' dune-project
+  $ sed -i '4s|.*|(source (gitlab user/repo))|' dune-project
   $ dune build
   $ cat foo.opam | grep -i gitlab
   homepage: "https://gitlab.com/user/repo"
@@ -30,16 +30,16 @@ Test a generated 'gitlab' user repo
 
 Test a generated 'sourcehut' user repo
 
-  $ sed -i '4c\(source (sourcehut user/repo))' dune-project
+  $ sed -i '4s|.*|(source (sourcehut user/repo))|' dune-project
   $ dune build
   $ cat foo.opam | grep -i sr.ht
   homepage: "https://sr.ht/~user/repo"
   bug-reports: "https://todo.sr.ht/~user/repo"
   dev-repo: "git+https://git.sr.ht/~user/repo"
 
-Test a generated 'bitbucket' ruser repo
+Test a generated 'bitbucket' user repo
 
-  $ sed -i '4c\(source (bitbucket user/repo))' dune-project
+  $ sed -i '4s|.*|(source (bitbucket user/repo))|' dune-project
   $ dune build
   $ cat foo.opam | grep -i bitbucket
   homepage: "https://bitbucket.org/user/repo"
@@ -48,9 +48,46 @@ Test a generated 'bitbucket' ruser repo
 
 Test a generated 'gitlab' organization repo
 
-  $ sed -i '4c\(source (gitlab organization/project/repo))' dune-project
+  $ sed -i '4s|.*|(source (gitlab organization/project/repo))|' dune-project
   $ dune build
   $ cat foo.opam | grep -i gitlab
   homepage: "https://gitlab.com/organization/project/repo"
   bug-reports: "https://gitlab.com/organization/project/repo/-/issues"
   dev-repo: "git+https://gitlab.com/organization/project/repo.git"
+
+Test that the creation of a source stanza of the form 'org/project/repo' is
+disallowed by any forge type other than gitlab and that associated error
+messages are provided
+
+Test github forge.
+
+  $ sed -i '4s|.*|(source (github org/proj/repo))|' dune-project
+  $ dune build
+  File "dune-project", line 4, characters 16-29:
+  4 | (source (github org/proj/repo))
+                      ^^^^^^^^^^^^^
+  Error: Github repository must be of form user/repo
+  Hint: The provided form 'org/proj/repo' is specific to Gitlab projects
+  [1]
+
+Test bitbucket forge.
+
+  $ sed -i '4s|.*|(source (bitbucket org/proj/repo))|' dune-project
+  $ dune build
+  File "dune-project", line 4, characters 19-32:
+  4 | (source (bitbucket org/proj/repo))
+                         ^^^^^^^^^^^^^
+  Error: Bitbucket repository must be of form user/repo
+  Hint: The provided form 'org/proj/repo' is specific to Gitlab projects
+  [1]
+
+Test sourcehut forge.
+
+  $ sed -i '4s|.*|(source (sourcehut org/proj/repo))|' dune-project
+  $ dune build
+  File "dune-project", line 4, characters 19-32:
+  4 | (source (sourcehut org/proj/repo))
+                         ^^^^^^^^^^^^^
+  Error: Sourcehut repository must be of form user/repo
+  Hint: The provided form 'org/proj/repo' is specific to Gitlab projects
+  [1]