chore: rename default branch to main (#6071)

* chore: rename default branch to main

* Rename new master references

ARCHITECTURE.md

@@ -203,14 +203,14 @@ options it accepts should also call
 [`google::cloud::internal::CheckExpectedOptions<...>(...)`][check-expected-example-link]
 in order to help users diagnose option-related issues in their code.
 
-[spanner-connection-options-link]: https://github.com/googleapis/google-cloud-cpp/blob/master/google/cloud/spanner/connection_options.h
-[query-options-link]: https://github.com/googleapis/google-cloud-cpp/blob/master/google/cloud/spanner/query_options.h
-[client-options-link]: https://github.com/googleapis/google-cloud-cpp/blob/master/google/cloud/storage/client_options.h
-[common-options-link]: https://github.com/googleapis/google-cloud-cpp/blob/master/google/cloud/common_options.h
-[grpc-options-link]: https://github.com/googleapis/google-cloud-cpp/blob/master/google/cloud/grpc_options.h
-[spanner-options-link]: https://github.com/googleapis/google-cloud-cpp/blob/master/google/cloud/spanner/options.h
-[options-link]: https://github.com/googleapis/google-cloud-cpp/blob/master/google/cloud/options.h
-[spanner-defaults-link]: https://github.com/googleapis/google-cloud-cpp/blob/master/google/cloud/spanner/internal/defaults.h
+[spanner-connection-options-link]: https://github.com/googleapis/google-cloud-cpp/blob/main/google/cloud/spanner/connection_options.h
+[query-options-link]: https://github.com/googleapis/google-cloud-cpp/blob/main/google/cloud/spanner/query_options.h
+[client-options-link]: https://github.com/googleapis/google-cloud-cpp/blob/main/google/cloud/storage/client_options.h
+[common-options-link]: https://github.com/googleapis/google-cloud-cpp/blob/main/google/cloud/common_options.h
+[grpc-options-link]: https://github.com/googleapis/google-cloud-cpp/blob/main/google/cloud/grpc_options.h
+[spanner-options-link]: https://github.com/googleapis/google-cloud-cpp/blob/main/google/cloud/spanner/options.h
+[options-link]: https://github.com/googleapis/google-cloud-cpp/blob/main/google/cloud/options.h
+[spanner-defaults-link]: https://github.com/googleapis/google-cloud-cpp/blob/main/google/cloud/spanner/internal/defaults.h
 [check-expected-example-link]: https://github.com/googleapis/google-cloud-cpp/blob/6bd0fae69af98939a1ba4fedea7bb20366ad15d9/google/cloud/spanner/client.cc#L358-L360
 
 ## Deviations from the "normal" Architecture

CMakeLists.txt

@@ -136,10 +136,10 @@ option(GOOGLE_CLOUD_CPP_GEN_DOCS_FOR_GOOGLEAPIS_DEV
        "Use relative URLs in docs for googleapis.dev" OFF)
 mark_as_advanced(GOOGLE_CLOUD_CPP_GEN_DOCS_FOR_GOOGLEAPIS_DEV)
 
-# Use master as the version part of the relative URLs.
-option(GOOGLE_CLOUD_CPP_USE_MASTER_FOR_REFDOC_LINKS
-       "Use master as the version part for refdoc relative links" OFF)
-mark_as_advanced(GOOGLE_CLOUD_CPP_USE_MASTER_FOR_REFDOC_LINKS)
+# Use main as the version part of the relative URLs.
+option(GOOGLE_CLOUD_CPP_USE_MAIN_FOR_REFDOC_LINKS
+       "Use main as the version part for refdoc relative links" OFF)
+mark_as_advanced(GOOGLE_CLOUD_CPP_USE_MAIN_FOR_REFDOC_LINKS)
 
 set(PROJECT_THIRD_PARTY_DIR "${PROJECT_SOURCE_DIR}/third_party")
 

README.md

@@ -18,7 +18,7 @@
 [kokoro-macos-cmake-link]: https://storage.googleapis.com/cloud-cpp-kokoro-status/macos/kokoro-cmake-super-link.html
 [kokoro-macos-bazel-shield]: https://storage.googleapis.com/cloud-cpp-kokoro-status/macos/kokoro-bazel.svg
 [kokoro-macos-bazel-link]: https://storage.googleapis.com/cloud-cpp-kokoro-status/macos/kokoro-bazel-link.html
-[codecov-shield]: https://codecov.io/gh/googleapis/google-cloud-cpp/branch/master/graph/badge.svg
+[codecov-shield]: https://codecov.io/gh/googleapis/google-cloud-cpp/branch/main/graph/badge.svg
 [codecov-link]: https://codecov.io/gh/googleapis/google-cloud-cpp
 [gcb-clang-tidy-shield]: https://storage.googleapis.com/cloud-cpp-community-publiclogs/badges/google-cloud-cpp/main/clang-tidy.svg
 [gcb-clang-tidy-link]: https://storage.googleapis.com/cloud-cpp-community-publiclogs/badges/google-cloud-cpp/main/clang-tidy.html
@@ -156,7 +156,7 @@ int main(int argc, char* argv[]) {
 * This project supports Windows, macOS, Linux
 * This project supports C++11 (and higher) compilers (we test with GCC \>= 5.4, Clang >= 3.8, and MSVC \>= 2019)
 * This project supports Bazel and CMake builds. See the [Quickstart examples](https://github.com/googleapis/google-cloud-cpp#quickstart)
-* This project uses dependencies described in [doc/packaging.md](https://github.com/googleapis/google-cloud-cpp/blob/master/doc/packaging.md)
+* This project uses dependencies described in [doc/packaging.md](https://github.com/googleapis/google-cloud-cpp/blob/main/doc/packaging.md)
 * This project works with or without exceptions enabled
 * This project cuts [monthly releases](https://github.com/googleapis/google-cloud-cpp/releases) with detailed release notes
 

ci/cloudbuild/builds/cmake-super.sh

@@ -29,4 +29,4 @@ cmake -GNinja \
   -Hsuper -Bcmake-out
 cmake --build cmake-out
 # Testing is automatically done by the super build itself. See
-# https://github.com/googleapis/google-cloud-cpp/blob/master/super/CMakeLists.txt
+# https://github.com/googleapis/google-cloud-cpp/blob/main/super/CMakeLists.txt

ci/coverity-scan.sh

@@ -57,6 +57,6 @@ tar caf google-cloud-cpp.tar.xz cov-int
 curl --form "token=${COVERITY_SCAN_TOKEN}" \
   --form email="${COVERITY_SCAN_EMAIL}" \
   --form file=@google-cloud-cpp.tar.xz \
-  --form version="master" \
+  --form version="main" \
   --form description="Automatically Compiled Coverity Scan" \
   https://scan.coverity.com/builds?project=googleapis%2Fgoogle-cloud-cpp

ci/generate-markdown/generate-bigtable-readme.sh

@@ -49,7 +49,7 @@ Please note that the Google Cloud C++ client libraries do **not** follow
 
 [doxygen-link]: https://googleapis.dev/cpp/google-cloud-bigtable/latest/
 [cloud-bigtable-docs]: https://cloud.google.com/bigtable/docs/
-[source-link]: https://github.com/googleapis/google-cloud-cpp/tree/master/google/cloud/bigtable
+[source-link]: https://github.com/googleapis/google-cloud-cpp/tree/main/google/cloud/bigtable
 
 ## Quickstart
 

ci/generate-markdown/generate-pubsub-readme.sh

@@ -49,7 +49,7 @@ Please note that the Google Cloud C++ client libraries do **not** follow
 
 [doxygen-link]: https://googleapis.dev/cpp/google-cloud-pubsub/latest/
 [cloud-spanner-docs]: https://cloud.google.com/pubsub/docs/
-[source-link]: https://github.com/googleapis/google-cloud-cpp/tree/master/google/cloud/pubsub
+[source-link]: https://github.com/googleapis/google-cloud-cpp/tree/main/google/cloud/pubsub
 
 ## Quickstart
 

ci/generate-markdown/generate-readme.sh

@@ -43,7 +43,7 @@ cat <<"EOF"
 [kokoro-macos-cmake-link]: https://storage.googleapis.com/cloud-cpp-kokoro-status/macos/kokoro-cmake-super-link.html
 [kokoro-macos-bazel-shield]: https://storage.googleapis.com/cloud-cpp-kokoro-status/macos/kokoro-bazel.svg
 [kokoro-macos-bazel-link]: https://storage.googleapis.com/cloud-cpp-kokoro-status/macos/kokoro-bazel-link.html
-[codecov-shield]: https://codecov.io/gh/googleapis/google-cloud-cpp/branch/master/graph/badge.svg
+[codecov-shield]: https://codecov.io/gh/googleapis/google-cloud-cpp/branch/main/graph/badge.svg
 [codecov-link]: https://codecov.io/gh/googleapis/google-cloud-cpp
 [gcb-clang-tidy-shield]: https://storage.googleapis.com/cloud-cpp-community-publiclogs/badges/google-cloud-cpp/main/clang-tidy.svg
 [gcb-clang-tidy-link]: https://storage.googleapis.com/cloud-cpp-community-publiclogs/badges/google-cloud-cpp/main/clang-tidy.html
@@ -142,7 +142,7 @@ cat <<"EOF"
 * This project supports Windows, macOS, Linux
 * This project supports C++11 (and higher) compilers (we test with GCC \>= 5.4, Clang >= 3.8, and MSVC \>= 2019)
 * This project supports Bazel and CMake builds. See the [Quickstart examples](https://github.com/googleapis/google-cloud-cpp#quickstart)
-* This project uses dependencies described in [doc/packaging.md](https://github.com/googleapis/google-cloud-cpp/blob/master/doc/packaging.md)
+* This project uses dependencies described in [doc/packaging.md](https://github.com/googleapis/google-cloud-cpp/blob/main/doc/packaging.md)
 * This project works with or without exceptions enabled
 * This project cuts [monthly releases](https://github.com/googleapis/google-cloud-cpp/releases) with detailed release notes
 

ci/generate-markdown/generate-spanner-readme.sh

@@ -49,7 +49,7 @@ Please note that the Google Cloud C++ client libraries do **not** follow
 
 [doxygen-link]: https://googleapis.dev/cpp/google-cloud-spanner/latest/
 [cloud-spanner-docs]: https://cloud.google.com/spanner/docs/
-[source-link]: https://github.com/googleapis/google-cloud-cpp/tree/master/google/cloud/spanner
+[source-link]: https://github.com/googleapis/google-cloud-cpp/tree/main/google/cloud/spanner
 
 ## Quickstart
 

ci/generate-markdown/generate-storage-readme.sh

@@ -52,7 +52,7 @@ Please note that the Google Cloud C++ client libraries do **not** follow
 
 [doxygen-link]: https://googleapis.dev/cpp/google-cloud-storage/latest/
 [cloud-storage-docs]: https://cloud.google.com/storage/docs/
-[source-link]: https://github.com/googleapis/google-cloud-cpp/tree/master/google/cloud/storage
+[source-link]: https://github.com/googleapis/google-cloud-cpp/tree/main/google/cloud/storage
 
 ## Quickstart
 

ci/kokoro/README.md

@@ -62,7 +62,7 @@ little bit, we cache these images in Google Container Registry (GCR). Builds
 triggered by GitHub pull requests download the cached image, then use that cache
 to rebuild the image (which usually results in "nothing to rebuild") and then
 run the build using the newly created image. Builds triggered by GitHub commits
-to a branch (typically `master` or a release branch) only use the cache if
+to a branch (typically `main` or a release branch) only use the cache if
 rebuilding the image from scratch fails. Such builds also push new versions of
 the cached image to GCR.
 

ci/kokoro/macos/build.sh

@@ -136,7 +136,7 @@ rm -f "${GRPC_DEFAULT_SSL_ROOTS_FILE_PATH}"
 curl -sSL --retry 10 -o "${GRPC_DEFAULT_SSL_ROOTS_FILE_PATH}" \
   https://pki.google.com/roots.pem
 
-BRANCH="${KOKORO_GITHUB_PULL_REQUEST_TARGET_BRANCH:-master}"
+BRANCH="${KOKORO_GITHUB_PULL_REQUEST_TARGET_BRANCH:-main}"
 readonly BRANCH
 echo "================================================================"
 io::log_yellow "detected the branch name: ${BRANCH}."

ci/kokoro/windows/build.ps1

@@ -50,7 +50,7 @@ the KOKORO_JOB_NAME environment variable.
 # TODO(#4896): Enable generator integration tests for windows.
 $env:GOOGLE_CLOUD_CPP_GENERATOR_RUN_INTEGRATION_TESTS = "no"
 
-$env:BUILD_CACHE = "gs://cloud-cpp-kokoro-results/build-cache/google-cloud-cpp/master/vcpkg-binary-cache/windows/${BuildName}/"
+$env:BUILD_CACHE = "gs://cloud-cpp-kokoro-results/build-cache/google-cloud-cpp/main/vcpkg-binary-cache/windows/${BuildName}/"
 $DependencyScriptArgs=@()
 if (($BuildName -eq "cmake") -or ($BuildName -eq "cmake-debug")) {
     $env:CONFIG = "Debug"

doc/adr/2019-01-04-error-reporting-with-statusor.md

@@ -31,7 +31,7 @@ no immediate plans to change the API for Cloud Bigtable. We will communicate a
 timeline to change this API in a separate document.
 
 [badbit-link]: https://en.cppreference.com/w/cpp/io/ios_base/iostate
-[gcs-link]: https://github.com/googleapis/google-cloud-cpp/tree/master/google/cloud/storage
-[bigtable-link]: https://github.com/googleapis/google-cloud-cpp/tree/master/google/cloud/bigtable
+[gcs-link]: https://github.com/googleapis/google-cloud-cpp/tree/main/google/cloud/storage
+[bigtable-link]: https://github.com/googleapis/google-cloud-cpp/tree/main/google/cloud/bigtable
 [survey-link]: https://isocpp.org/blog/2018/03/results-summary-cpp-foundation-developer-survey-lite-2018-02
 

doc/contributor/howto-guide-forks-and-pull-requests.md

@@ -37,13 +37,13 @@ To pull new commits from `upstream` into your local repo and
 [sync your fork][syncing-a-fork] you can do the following:
 
 ```console
-git checkout master
-git pull --ff-only upstream master
+git checkout main
+git pull --ff-only upstream main
 git push  # Pushes new commits up to your fork on GitHub
 ```
 
 > :attention: you probably want to do this periodically, and almost certainly
-> before starting any new branches. Keeping your default branch (aka `master`)
+> before starting any new branches. Keeping your default branch (aka `main`)
 > in sync is important to make your pull requests easy to review.
 
 ## Preparing to make a pull requests
@@ -55,7 +55,7 @@ change for review you need to create a pull request. Typically you start by:
 1. Picking an existing [GitHub bug][mastering-issues] to work on.
 1. Create a new [branch][about-branches] for each feature (or bug fix).
    ```console
-   git checkout master
+   git checkout main
    git checkout -b my-feature-branch
    git push -u origin my-feature-branch  # Tells fork on GitHub about new branch
    # make your changes
@@ -71,15 +71,15 @@ change for review you need to create a pull request. Typically you start by:
 ### Resolving Conflicts and Rebasing
 
 From time to time your pull request may have conflicts with the destination
-branch (likely `master`). If so, we request that you [rebase][about-rebase]
+branch (likely `main`). If so, we request that you [rebase][about-rebase]
 your branch instead of merging. The reviews can become very confusing if you
-merge during a pull request. You should first ensure that your `master`
+merge during a pull request. You should first ensure that your `main`
 branch has all the latest commits by syncing your fork (see above), then do
 the following:
 
 ```shell
 git checkout my-feature-branch
-git rebase master
+git rebase main
 git push --force-with-lease
 ```
 
@@ -108,7 +108,7 @@ ci/cloudbuild/build.sh -t asan-pr --docker
 ## Merging the changes
 
 Eventually the reviewers accept your changes, and they are merged into the
-`master` branch. We use "squash commits", where all your commits become a single
+`main` branch. We use "squash commits", where all your commits become a single
 commit into the default branch. A project owner needs to merge your changes,
 if you are a project owner, the expectation is that you will perform the merge
 operation, and update the commit comments to something readable.

doc/contributor/howto-guide-setup-development-workstation.md

@@ -38,7 +38,7 @@ install additional tools to run the unit and integration tests.
 
 These instructions will describe how to install these tools for Ubuntu 18.04
 (Bionic Beaver). For other distributions you may consult the Dockerfiles in
-[ci/cloudbuild/dockerfiles/](https://github.com/googleapis/google-cloud-cpp/tree/master/ci/cloudbuild/dockerfiles)
+[ci/cloudbuild/dockerfiles/](https://github.com/googleapis/google-cloud-cpp/tree/main/ci/cloudbuild/dockerfiles)
 If you use a different distribution, you will need to use the corresponding
 package manager (`dnf`, `zypper`, `apk`, etc.) and find the corresponding
 package names.

google/cloud/README.md

@@ -30,7 +30,7 @@ notice. These include `google/cloud/internal/`, and
 * Detailed header comments in our [public `.h`][source-link] files
 
 [doxygen-link]: https://googleapis.dev/cpp/google-cloud-common/latest/
-[source-link]: https://github.com/googleapis/google-cloud-cpp/tree/master/google/cloud
+[source-link]: https://github.com/googleapis/google-cloud-cpp/tree/main/google/cloud
 
 ## Contributing changes
 

google/cloud/bigtable/README.md

@@ -25,7 +25,7 @@ Please note that the Google Cloud C++ client libraries do **not** follow
 
 [doxygen-link]: https://googleapis.dev/cpp/google-cloud-bigtable/latest/
 [cloud-bigtable-docs]: https://cloud.google.com/bigtable/docs/
-[source-link]: https://github.com/googleapis/google-cloud-cpp/tree/master/google/cloud/bigtable
+[source-link]: https://github.com/googleapis/google-cloud-cpp/tree/main/google/cloud/bigtable
 
 ## Quickstart
 

google/cloud/pubsub/README.md

@@ -25,7 +25,7 @@ Please note that the Google Cloud C++ client libraries do **not** follow
 
 [doxygen-link]: https://googleapis.dev/cpp/google-cloud-pubsub/latest/
 [cloud-spanner-docs]: https://cloud.google.com/pubsub/docs/
-[source-link]: https://github.com/googleapis/google-cloud-cpp/tree/master/google/cloud/pubsub
+[source-link]: https://github.com/googleapis/google-cloud-cpp/tree/main/google/cloud/pubsub
 
 ## Quickstart
 

google/cloud/spanner/README.md

@@ -25,7 +25,7 @@ Please note that the Google Cloud C++ client libraries do **not** follow
 
 [doxygen-link]: https://googleapis.dev/cpp/google-cloud-spanner/latest/
 [cloud-spanner-docs]: https://cloud.google.com/spanner/docs/
-[source-link]: https://github.com/googleapis/google-cloud-cpp/tree/master/google/cloud/spanner
+[source-link]: https://github.com/googleapis/google-cloud-cpp/tree/main/google/cloud/spanner
 
 ## Quickstart
 

google/cloud/spanner/options.cc

@@ -22,7 +22,7 @@ inline namespace SPANNER_CLIENT_NS {
 // This empty .cc file eliminated false positive errors from clang-tidy in our
 // presubmit CI. Not exactly sure why, but I was able to reproduce the error
 // locally with:
-//   $ KOKORO_GITHUB_PULL_REQUEST_TARGET_BRANCH=master
+//   $ KOKORO_GITHUB_PULL_REQUEST_TARGET_BRANCH=main
 //         KOKORO_JOB_TYPE=PRESUBMIT_GITHUB
 //         ./ci/kokoro/docker/build.sh clang-tidy
 

google/cloud/storage/README.md

@@ -28,7 +28,7 @@ Please note that the Google Cloud C++ client libraries do **not** follow
 
 [doxygen-link]: https://googleapis.dev/cpp/google-cloud-storage/latest/
 [cloud-storage-docs]: https://cloud.google.com/storage/docs/
-[source-link]: https://github.com/googleapis/google-cloud-cpp/tree/master/google/cloud/storage
+[source-link]: https://github.com/googleapis/google-cloud-cpp/tree/main/google/cloud/storage
 
 ## Quickstart