Fix nested subrepos

.gitignore

@@ -0,0 +1,2 @@
+.emacs-saves
+*#*

Makefile

@@ -15,9 +15,17 @@ SHARE = share
 
 # Install variables:
 PREFIX ?= /usr/local
-INSTALL_LIB  ?= $(DESTDIR)$(shell git --exec-path)
+GIT ?= git
+INSTALL_LIB  ?= $(shell $(GIT) --exec-path)
 INSTALL_EXT  ?= $(INSTALL_LIB)/$(NAME).d
-INSTALL_MAN1 ?= $(DESTDIR)$(PREFIX)/share/man/man1
+INSTALL_MAN1 ?= $(PREFIX)/share/man/man1
+
+all:
+	echo $(INSTALL_LIB)
+	which git
+	git --exec-path
+
+
 
 # Basic targets:
 default: help

README.fix-nested-subrepos.txt

@@ -0,0 +1,84 @@
+Background:
+==========
+	Have a tree of ~270 nested subrepos of various levels
+
+                 top
+				  |
+				 subrepo0 -- top
+				      |
+					import
+				 /       |         \
+              subreop1 subreop2 .. subrepo140
+		          |
+		        import    ...
+				 /    \
+			sibreopo141 ..
+
+
+		checkout time for all files of the 'top' subrepo is about 20 min
+
+Issues found:
+============
+
+   1. 'subrepo branch' for the top of the nested subrepos creates a tree which includes nested subrepos and pushes them tot he
+   	  origin
+
+   2. 'subrepo bfanch' created nested references which just do not work in case of the multiple branches in existence.
+      e.g.: error: cannot lock ref 'refs/heads/subrepo/s1': 'refs/heads/subrepo/s1/s5/s6' exists; cannot create 'refs/heads/subrepo/s1'
+
+   3. '--tree-filter' used int the branch filtering is veeeery slow. My initial experinent of creating a branch for 'subrepo0' took
+   	  52 hours.
+
+   4. 'multiple commands are missing the --ALL' qualifier
+
+
+Bugs found:
+==========
+
+    1. Worktree was not cleaned at subrepo:branch. It was causing issues in push --ALL if some branches already existed.
+
+	2. test/branch-rev-list-one-path.t failed internittently
+
+	3. encoding did not catch single '@' correclty, causing worktree creation to fail, at least in git 2.22
+
+Features change:
+===============
+
+    1. git 2.22 message letter casing was changed from 'Couldn't find remote ref' to 'couldn't find remote ref'.
+
+
+Added changes:
+=============
+	1. Added feature to clean nested subrepo in the filter-branch
+
+	2. flattened names of nested branches by replaceing '/' with '-'
+
+	3. Added extra checking for the updates done to the nested subrepos only. It checks updated files against the nested subrepo regex
+	   -- found a code which created EMPTY commits, which looked like a leftower from debugging. It stayed in the way and I
+	      commented it out. Did not affect any test.
+	   -- it reduced number of revisions needed for subrepo0 in my initial case from 268 to 4 :-) 
+
+	4. Replaced --tree-filter with --index-filter in soc:branch. For different subrepos performance was improved 2x to 10x.
+	   -- found a git issue, probably related to the tree size. It crashed in filter-branch with `xrealloc(-1ULL)`. I did not
+	   	investigate it further. This happened to the top subrepo with 268 revisions. It worked with 4 (from above) and took onlly 7
+		min to finish (vs 52 hours initially)
+
+		-- aded the '--use_tree_filter' qualifier to allow old --tree-filter in case of git issues.
+
+    5. added the --squash_branch (-S) feature to the branch, push, pull, and fetch commands. It causes subrepo:branch to squash all commits into
+       one with combined log. This was initially done for performance reasons
+
+	6. fixed found bugs and updated features.
+
+	   -- added --ALL to 'branch', 'clean', 'fetch', 'pull', and 'push'
+	   -- added --topo-order to 'rev-list' in subrepo:branch. This makes git reporting consistent and it looks like
+	      branch-rev-list-one-path.t  passes consistently now
+	   -- claned 'wortree' in subrepo:branch before checking for existense fo the branch
+	   -- added checking of non-prefixed branch names to the encoding. It was ok for branches but not ok for worktrees. Now
+	      worktree seems to work.
+	   -- fixed message regex to handle both, capitalized and non-capitalized veresion of the '[Cc]ouldn't'
+
+    7. added nested.t test to check both regular and squashed branches.
+
+
+