a todo on: explicit metadata needed for view inclusion or not

doc/todo/explicit_metadata_needed_for_view_inclusion_or_not.mdwn

@@ -0,0 +1,115 @@
+I'm not sure if this is a bug or a feature but the question is should files have (some/any)
+explicit metadata set with `git-annex metadata` for them to be included in a view branch?
+I mean if you create a view with just path-based fields (say, restrict to a subdirectory
+with a criterion like 'subdir/=*'), do you expect files to match even if they don't have
+any metadata fields manually set? In release version 10.20230214 the behavior has changed
+in that files that don't have manual metadata set don't seem to be included in 
+(directory-based) view branches. The inverse seems to be true of the unreleased version
+10.20230127-gc209e0f64 committed a week before.
+
+In my opinion, this *could* be a feature if it's documented but it could also be construed
+as violating the principle of least surprise as not all users routinely tag all annexed files
+with metadata.
+
+The following is a transcript that illustrates how the recent release version behaves. See
+how the file `subdir/c` is excluded from the view branch (my apologies for this being a
+PowerShell session on Windows):
+
+[[!format sh """
+X:\> cd git-annex-tests
+X:\git-annex-tests> git init annex-view-test-a
+X:\git-annex-tests> cd .\annex-view-test-a\
+X:\git-annex-tests\annex-view-test-a [master]> git config annex.thin true
+X:\git-annex-tests\annex-view-test-a [master]> git annex init Annex-view-test-a
+X:\git-annex-tests\annex-view-test-a [adjusted/master(unlocked)]> echo Aaa > a
+X:\git-annex-tests\annex-view-test-a [adjusted/master(unlocked) +1 ~0 -0 !]> mkdir subdir
+X:\git-annex-tests\annex-view-test-a [adjusted/master(unlocked) +1 ~0 -0 !]> echo Bbb > subdir\b
+X:\git-annex-tests\annex-view-test-a [adjusted/master(unlocked) +2 ~0 -0 !]> echo Ccc > subdir\c
+X:\git-annex-tests\annex-view-test-a [adjusted/master(unlocked) +2 ~0 -0 !]> mkdir subdir\subsubdir
+X:\git-annex-tests\annex-view-test-a [adjusted/master(unlocked) +2 ~0 -0 !]> echo Ddd > .\subdir\subsubdir\d
+X:\git-annex-tests\annex-view-test-a [adjusted/master(unlocked) +2 ~0 -0 !]> git annex add .
+add a
+ok
+add subdir/b
+ok
+add subdir/c
+ok
+add subdir/subsubdir/d
+ok
+(recording state in git...)
+X:\git-annex-tests\annex-view-test-a [adjusted/master(unlocked) +4 ~0 -0 ~]> ls -r
+
+    Directory: X:\git-annex-tests\annex-view-test-a
+
+Mode                 LastWriteTime         Length Name
+----                 -------------         ------ ----
+d----           15.2.2023    12:37                subdir
+-a---           15.2.2023    12:31              5 a
+
+    Directory: X:\git-annex-tests\annex-view-test-a\subdir
+
+Mode                 LastWriteTime         Length Name
+----                 -------------         ------ ----
+d----           15.2.2023    12:38                subsubdir
+-a---           15.2.2023    12:34              5 b
+-a---           15.2.2023    12:37              5 c
+
+    Directory: X:\git-annex-tests\annex-view-test-a\subdir\subsubdir
+
+Mode                 LastWriteTime         Length Name
+----                 -------------         ------ ----
+-a---           15.2.2023    12:38              5 d
+
+X:\git-annex-tests\annex-view-test-a [adjusted/master(unlocked) +4 ~0 -0 ~]> fsutil hardlink list a
+\git-annex-tests\annex-view-test-a\.git\annex\objects\b29\a20\SHA256E-s5--e3c555b2205407e76d3a460513cf44c1c62e48ba83ec4948ed05d0f87b957051\SHA256E-s5--e3c555b2205407e76d3a460513cf44c1c62e48ba83ec4948ed05d0f87b957051
+\git-annex-tests\annex-view-test-a\a
+X:\git-annex-tests\annex-view-test-a [adjusted/master(unlocked) +4 ~0 -0 ~]> git commit -m 'Add test files'
+[adjusted/master(unlocked) 56b11c9] Add test files
+ 4 files changed, 4 insertions(+)
+ create mode 100644 a
+ create mode 100644 subdir/b
+ create mode 100644 subdir/c
+ create mode 100644 subdir/subsubdir/d
+X:\git-annex-tests\annex-view-test-a [adjusted/master(unlocked)]> git annex metadata -t test subdir\b
+metadata subdir/b
+  lastchanged=2023-02-15@10-52-31
+  tag=test
+  tag-lastchanged=2023-02-15@10-52-31
+ok
+(recording state in git...)
+X:\git-annex-tests\annex-view-test-a [adjusted/master(unlocked)]> git annex metadata -t test subdir\subsubdir\d
+metadata subdir/subsubdir/d
+  lastchanged=2023-02-15@10-53-00
+  tag=test
+  tag-lastchanged=2023-02-15@10-53-00
+ok
+(recording state in git...)
+X:\git-annex-tests\annex-view-test-a [adjusted/master(unlocked)]> git annex metadata subdir\c
+metadata subdir/c
+
+ok
+X:\git-annex-tests\annex-view-test-a [adjusted/master(unlocked)]> git annex view 'subdir\=*'
+view (searching...)
+Switched to branch 'views/adjusted/master(unlocked)(subdir_=_)'
+ok
+X:\git-annex-tests\annex-view-test-a [views/adjusted/master(unlocked)(subdir_=_)]> ls -r
+
+    Directory: X:\git-annex-tests\annex-view-test-a
+
+Mode                 LastWriteTime         Length Name
+----                 -------------         ------ ----
+d----           15.2.2023    12:55                subsubdir
+-a---           15.2.2023    12:55            178 b_%subdir%
+
+    Directory: X:\git-annex-tests\annex-view-test-a\subsubdir
+
+Mode                 LastWriteTime         Length Name
+----                 -------------         ------ ----
+-a---           15.2.2023    12:55            181 d_%subdir%subsubdir%
+
+# End of transcript or log.
+"""]]
+
+
+[[!meta author=jkniiv]]
+