test-merge-types.t: add tests for :merge-local/:merge-other with symlinks

This had no test coverage.

tests/test-merge-types.t

@@ -105,6 +105,50 b' Symlink is other parent, executable is l'
   a is an executable file with content:
   a
 
+  $ hg update -C 1
+  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
+
+  $ hg merge --debug --tool :merge-local
+    searching for copies back to rev 1
+  resolving manifests
+   branchmerge: True, force: False, partial: False
+   ancestor: c334dc3be0da, local: 3574f3e69b1c+, remote: 521a1e40188f
+   preserving a for resolve of a
+   a: versions differ -> m (premerge)
+  picked tool ':merge-local' for a (binary False symlink True)
+  merging a
+  my a@3574f3e69b1c+ other a@521a1e40188f ancestor a@c334dc3be0da
+  warning: :merge-local cannot merge symlinks for a
+  0 files updated, 0 files merged, 0 files removed, 1 files unresolved
+  use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon
+  [1]
+
+  $ tellmeabout a
+  a is an executable file with content:
+  a
+
+  $ hg update -C 1
+  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
+
+  $ hg merge --debug --tool :merge-other
+    searching for copies back to rev 1
+  resolving manifests
+   branchmerge: True, force: False, partial: False
+   ancestor: c334dc3be0da, local: 3574f3e69b1c+, remote: 521a1e40188f
+   preserving a for resolve of a
+   a: versions differ -> m (premerge)
+  picked tool ':merge-other' for a (binary False symlink True)
+  merging a
+  my a@3574f3e69b1c+ other a@521a1e40188f ancestor a@c334dc3be0da
+  warning: :merge-other cannot merge symlinks for a
+  0 files updated, 0 files merged, 0 files removed, 1 files unresolved
+  use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon
+  [1]
+
+  $ tellmeabout a
+  a is an executable file with content:
+  a
+
 Update to link without local change should get us a symlink (issue3316):
 
   $ hg up -C 0