phabricator: add a small language to query Differential Revisions
Previously, `phabread` can only be used to read a single patch, or a single
stack of patches. In the future, we want to have more complex queries like
filtering with status (open, accepted, closed, etc), or maybe more complex
like filtering by reviewers etc. The command line flag approach won't scale
with that.
Besides, we might want to have other commands to update Differential
Revision status in batch, like accepting a stack using a single command.
Therefore, this patch adds a small language. It has basic set operations:
`&`, `+`, `-` and an ancestor operator to support `--stack`.
Test Plan:
Try querying this Phabricator instance:
hg phabread 1+2 # 1, 2
hg phabread D2+D1 # 2, 1
hg phabread ':118-115+:2-1' # 114, 116, 117, 118, 2
hg phabread '((:118-(D115+117)))&:117' # 114, 116
hg phabread ':2&:117' --debug # differential.query is called only once
Make sure the output is expected and prefetch works.
Differential Revision: https://phab.mercurial-scm.org/D125
running: init test1
result: None
running: add foo
result: 0
running: commit -m commit1 -d 2000-01-01 foo
result: None
running: commit -m commit2 -d 2000-01-02 foo
result: None
running: log -r 0
changeset: 0:0e4634943879
user: test
date: Sat Jan 01 00:00:00 2000 +0000
summary: commit1
result: None
running: log -r tip
changeset: 1:45589e459b2e
tag: tip
user: test
date: Sun Jan 02 00:00:00 2000 +0000
summary: commit2
result: None