phabricator: rework phabread to reduce memory usage and round-trips
This patch reworked phabread a bit so it fetches the lightweight
"Differential Revision" metadata for a stack first. Then read other data.
This allows the code to:
a) send 1 request to get all `hg:meta` data instead of N requests
b) patches are read in desired order, no need to buffer the output
"b)" reduces the memory usage from O(N^2) to O(N) since we no longer keep
old patch contents in memory.
The above `N` means the number of patches in the stack.
Initial setup.
$ hg init repo
$ cd repo
$ touch thefile
$ hg ci -A -m 'Initial commit.'
adding thefile
Create a tag.
$ hg tag branchortag
Create a branch with the same name as the tag.
$ hg branch branchortag
marked working directory as branch branchortag
(branches are permanent and global, did you want a bookmark?)
$ hg ci -m 'Create a branch with the same name as a tag.'
This is what we have:
$ hg log
changeset: 2:10519b3f489a
branch: branchortag
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: Create a branch with the same name as a tag.
changeset: 1:2635c45ca99b
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: Added tag branchortag for changeset f57387372b5d
changeset: 0:f57387372b5d
tag: branchortag
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: Initial commit.
Update to the tag:
$ hg up 'tag(branchortag)'
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ hg parents
changeset: 0:f57387372b5d
tag: branchortag
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: Initial commit.
Updating to the branch:
$ hg up 'branch(branchortag)'
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg parents
changeset: 2:10519b3f489a
branch: branchortag
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: Create a branch with the same name as a tag.
$ cd ..