Merge branch 'nd/shallow-deepen'

The existing "git fetch --depth=<n>" option was hard to use
correctly when making the history of an existing shallow clone
deeper.  A new option, "--deepen=<n>", has been added to make this
easier to use.  "git clone" also learned "--shallow-since=<date>"
and "--shallow-exclude=<tag>" options to make it easier to specify
"I am interested only in the recent N months worth of history" and
"Give me only the history since that version".

* nd/shallow-deepen: (27 commits)
  fetch, upload-pack: --deepen=N extends shallow boundary by N commits
  upload-pack: add get_reachable_list()
  upload-pack: split check_unreachable() in two, prep for get_reachable_list()
  t5500, t5539: tests for shallow depth excluding a ref
  clone: define shallow clone boundary with --shallow-exclude
  fetch: define shallow boundary with --shallow-exclude
  upload-pack: support define shallow boundary by excluding revisions
  refs: add expand_ref()
  t5500, t5539: tests for shallow depth since a specific date
  clone: define shallow clone boundary based on time with --shallow-since
  fetch: define shallow boundary with --shallow-since
  upload-pack: add deepen-since to cut shallow repos based on time
  shallow.c: implement a generic shallow boundary finder based on rev-list
  fetch-pack: use a separate flag for fetch in deepening mode
  fetch-pack.c: mark strings for translating
  fetch-pack: use a common function for verbose printing
  fetch-pack: use skip_prefix() instead of starts_with()
  upload-pack: move rev-list code out of check_non_tip()
  upload-pack: make check_non_tip() clean things up on error
  upload-pack: tighten number parsing at "deepen" lines
  ...

6 files changed, 75 insertions, 1 deletions

diff --git a/Documentation/fetch-options.txt b/Documentation/fetch-options.txt
index 9eab1f5fa4..fb6bebbc61 100644
--- a/Documentation/fetch-options.txt
+++ b/Documentation/fetch-options.txt
@@ -14,6 +14,20 @@
 	linkgit:git-clone[1]), deepen or shorten the history to the specified
 	number of commits. Tags for the deepened commits are not fetched.
 
+--deepen=<depth>::
+	Similar to --depth, except it specifies the number of commits
+	from the current shallow boundary instead of from the tip of
+	each remote branch history.
+
+--shallow-since=<date>::
+	Deepen or shorten the history of a shallow repository to
+	include all reachable commits after <date>.
+
+--shallow-exclude=<revision>::
+	Deepen or shorten the history of a shallow repository to
+	exclude commits reachable from a specified remote branch or tag.
+	This option can be specified multiple times.
+
 --unshallow::
 	If the source repository is complete, convert a shallow
 	repository to a complete one, removing all the limitations
diff --git a/Documentation/git-clone.txt b/Documentation/git-clone.txt
index e316c4bd51..35cc34b2fb 100644
--- a/Documentation/git-clone.txt
+++ b/Documentation/git-clone.txt
@@ -197,6 +197,14 @@ objects from the source repository into a pack in the cloned repository.
 	tips of all branches. If you want to clone submodules shallowly,
 	also pass `--shallow-submodules`.
 
+--shallow-since=<date>::
+	Create a shallow clone with a history after the specified time.
+
+--shallow-exclude=<revision>::
+	Create a shallow clone with a history, excluding commits
+	reachable from a specified remote branch or tag.  This option
+	can be specified multiple times.
+
 --[no-]single-branch::
 	Clone only the history leading to the tip of a single branch,
 	either specified by the `--branch` option or the primary
diff --git a/Documentation/git-fetch-pack.txt b/Documentation/git-fetch-pack.txt
index 24417ee3a6..d45f6adc69 100644
--- a/Documentation/git-fetch-pack.txt
+++ b/Documentation/git-fetch-pack.txt
@@ -87,6 +87,20 @@ be in a separate packet, and the list must end with a flush packet.
 	'git-upload-pack' treats the special depth 2147483647 as
 	infinite even if there is an ancestor-chain that long.
 
+--shallow-since=<date>::
+	Deepen or shorten the history of a shallow'repository to
+	include all reachable commits after <date>.
+
+--shallow-exclude=<revision>::
+	Deepen or shorten the history of a shallow repository to
+	exclude commits reachable from a specified remote branch or tag.
+	This option can be specified multiple times.
+
+--deepen-relative::
+	Argument --depth specifies the number of commits from the
+	current shallow boundary instead of from the tip of each
+	remote branch history.
+
 --no-progress::
 	Do not show the progress.
 
diff --git a/Documentation/gitremote-helpers.txt b/Documentation/gitremote-helpers.txt
index a4de50ad22..9e8681f9e1 100644
--- a/Documentation/gitremote-helpers.txt
+++ b/Documentation/gitremote-helpers.txt
@@ -415,6 +415,17 @@ set by Git if the remote helper has the 'option' capability.
 'option depth' <depth>::
 	Deepens the history of a shallow repository.
 
+'option deepen-since <timestamp>::
+	Deepens the history of a shallow repository based on time.
+
+'option deepen-not <ref>::
+	Deepens the history of a shallow repository excluding ref.
+	Multiple options add up.
+
+'option deepen-relative {'true'|'false'}::
+	Deepens the history of a shallow repository relative to
+	current boundary. Only valid when used with "option depth".
+
 'option followtags' {'true'|'false'}::
 	If enabled the helper should automatically fetch annotated
 	tag objects if the object the tag points at was transferred
diff --git a/Documentation/technical/pack-protocol.txt b/Documentation/technical/pack-protocol.txt
index 736f3894a8..c59ac9936a 100644
--- a/Documentation/technical/pack-protocol.txt
+++ b/Documentation/technical/pack-protocol.txt
@@ -219,7 +219,9 @@ out of what the server said it could do with the first 'want' line.
 
   shallow-line      =  PKT-LINE("shallow" SP obj-id)
 
-  depth-request     =  PKT-LINE("deepen" SP depth)
+  depth-request     =  PKT-LINE("deepen" SP depth) /
+		       PKT-LINE("deepen-since" SP timestamp) /
+		       PKT-LINE("deepen-not" SP ref)
 
   first-want        =  PKT-LINE("want" SP obj-id SP capability-list)
   additional-want   =  PKT-LINE("want" SP obj-id)
diff --git a/Documentation/technical/protocol-capabilities.txt b/Documentation/technical/protocol-capabilities.txt
index 4c28d3a8ae..26dcc6f502 100644
--- a/Documentation/technical/protocol-capabilities.txt
+++ b/Documentation/technical/protocol-capabilities.txt
@@ -179,6 +179,31 @@ This capability adds "deepen", "shallow" and "unshallow" commands to
 the  fetch-pack/upload-pack protocol so clients can request shallow
 clones.
 
+deepen-since
+------------
+
+This capability adds "deepen-since" command to fetch-pack/upload-pack
+protocol so the client can request shallow clones that are cut at a
+specific time, instead of depth. Internally it's equivalent of doing
+"rev-list --max-age=<timestamp>" on the server side. "deepen-since"
+cannot be used with "deepen".
+
+deepen-not
+----------
+
+This capability adds "deepen-not" command to fetch-pack/upload-pack
+protocol so the client can request shallow clones that are cut at a
+specific revision, instead of depth. Internally it's equivalent of
+doing "rev-list --not <rev>" on the server side. "deepen-not"
+cannot be used with "deepen", but can be used with "deepen-since".
+
+deepen-relative
+---------------
+
+If this capability is requested by the client, the semantics of
+"deepen" command is changed. The "depth" argument is the depth from
+the current shallow boundary, instead of the depth from remote refs.
+
 no-progress
 -----------