Rename a few masters

README.rst

@@ -191,8 +191,8 @@ To check if a feature branch adds at least one news fragment, run::
 
     towncrier check
 
-By default this compares the current branch against ``origin/master``. You can use ``--compare-with`` if the trunk is named differently::
+By default this compares the current branch against ``origin/main``. You can use ``--compare-with`` if the trunk is named differently::
 
-    towncrier check --compare-with origin/main
+    towncrier check --compare-with origin/master
 
 The check is automatically skipped when the main news file is modified inside the branch as this signals a release branch that is expected to not have news fragments.

setup.py

@@ -17,7 +17,7 @@
         "Mailing list": "https://mail.python.org/mailman3/lists/twisted.python.org/",
         "Issues": "https://github.com/twisted/towncrier/issues",
         "Repository": "https://github.com/twisted/towncrier",
-        "Tests": "https://github.com/twisted/towncrier/actions?query=branch%3Amaster",
+        "Tests": "https://github.com/twisted/towncrier/actions?query=branch%3Atrunk",
         "Coverage": "https://codecov.io/gh/twisted/towncrier",
         "Distribution": "https://pypi.org/project/towncrier",
     },

src/towncrier/check.py

@@ -45,7 +45,7 @@ def get_default_compare_branch(base_directory, encoding):
     help=(
         "Checks files changed running git diff --name-ony BRANCH... "
         "BRANCH is the branch to be compared with. "
-        "Default to origin/master"
+        "Default to origin/main"
     ),
 )
 @click.option(