Add a list of hashes to ignore during git blame. (#9560)

The hashes are from commits due to auto-formatting, e.g. running black.

git can be configured to use this automatically by running the following:

    git config blame.ignoreRevsFile .git-blame-ignore-revs

3 files changed, 10 insertions, 0 deletions

diff --git a/.git-blame-ignore-revs b/.git-blame-ignore-revs
new file mode 100644

index 0000000000..83ddd568c2
--- /dev/null
+++ b/.git-blame-ignore-revs
@@ -0,0 +1,8 @@
+# Black reformatting (#5482).
+32e7c9e7f20b57dd081023ac42d6931a8da9b3a3
+
+# Target Python 3.5 with black (#8664).
+aff1eb7c671b0a3813407321d2702ec46c71fa56
+
+# Update black to 20.8b1 (#9381).
+0a00b7ff14890987f09112a2ae696c61001e6cf1
diff --git a/changelog.d/9560.misc b/changelog.d/9560.misc
new file mode 100644

index 0000000000..57a698f846
--- /dev/null
+++ b/changelog.d/9560.misc
@@ -0,0 +1 @@
+Add a `.git-blame-ignore-revs` file with the hashes of auto-formatting.
diff --git a/setup.cfg b/setup.cfg

index f46e43fad0..5e301c2cd7 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -3,6 +3,7 @@ test_suite = tests
 
 [check-manifest]
 ignore =
+    .git-blame-ignore-revs
     contrib
     contrib/*
     docs/*