pre-commit: don't run dvc in parallel (#3912)

* pre-commit: use local hooks

* pre-commit: don't run dvc in parallel

By default pre-commit will try to run hooks in parallel, which results
in some dvc instances failing to acquire repo locks.

Fixes #3751

.pre-commit-config.yaml

@@ -27,18 +27,37 @@ repos:
   repo: https://github.com/lovesegfault/beautysh
   rev: master
 - hooks:
-  - id: dvc-pre-commit
-    language_version: python3
+  - args:
+    - git-hook
+    - pre-commit
+    entry: dvc
+    id: dvc-pre-commit
+    language: system
+    name: DVC pre-commit
     stages:
     - commit
-  - id: dvc-pre-push
-    language_version: python3
+    verbose: true
+    require_serial: true
+  - args:
+    - git-hook
+    - pre-push
+    entry: dvc
+    id: dvc-pre-push
+    language: system
+    name: DVC pre-push
     stages:
     - push
+    require_serial: true
   - always_run: true
+    args:
+    - git-hook
+    - post-checkout
+    entry: dvc
     id: dvc-post-checkout
-    language_version: python3
+    language: system
+    minimum_pre_commit_version: 2.2.0
+    name: DVC post-checkout
     stages:
     - post-checkout
-  repo: https://github.com/iterative/dvc
-  rev: master
+    require_serial: true
+  repo: local

.pre-commit-hooks.yaml

@@ -6,6 +6,7 @@
   language: python
   language_version: python3
   name: DVC pre-commit
+  require_serial: true
   stages:
   - commit
   verbose: true
@@ -17,6 +18,7 @@
   language: python
   language_version: python3
   name: DVC pre-push
+  require_serial: true
   stages:
   - push
 - always_run: true
@@ -29,5 +31,6 @@
   language_version: python3
   minimum_pre_commit_version: 2.2.0
   name: DVC post-checkout
+  require_serial: true
   stages:
   - post-checkout

scripts/ci/check_patch.sh

@@ -3,7 +3,7 @@
 set -x
 set -e
 
-pip install Pygments collective.checkdocs pre-commit
+pip install Pygments collective.checkdocs pre-commit .
 
 # stop the build if there are any readme formatting errors
 python setup.py checkdocs