From 12053d00ea93299dc5c25cb2f6daae3c7fde5ebc Mon Sep 17 00:00:00 2001
From: Alexander Biggs <akbiggs@users.noreply.github.com>
Date: Mon, 27 Sep 2021 20:53:02 -0400
Subject: [PATCH] [fuchsia] Small shell scripts for workflow.
 (flutter/engine#28823)

---
 .../fuchsia/devshell/branch_from_fuchsia.sh   | 30 +++++++++++++++++++
 .../tools/fuchsia/devshell/lib/vars.sh        |  9 ++++++
 .../tools/fuchsia/devshell/sync_to_fuchsia.sh | 21 +++++++++++++
 3 files changed, 60 insertions(+)
 create mode 100755 engine/src/flutter/tools/fuchsia/devshell/branch_from_fuchsia.sh
 create mode 100755 engine/src/flutter/tools/fuchsia/devshell/sync_to_fuchsia.sh

diff --git a/engine/src/flutter/tools/fuchsia/devshell/branch_from_fuchsia.sh b/engine/src/flutter/tools/fuchsia/devshell/branch_from_fuchsia.sh
new file mode 100755
index 00000000000..ab548d0219c
--- /dev/null
+++ b/engine/src/flutter/tools/fuchsia/devshell/branch_from_fuchsia.sh
@@ -0,0 +1,30 @@
+#!/bin/bash
+# Copyright 2013 The Flutter Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+#
+### Starts a new branch from Fuchsia's checkout of the Flutter engine.
+### This is necessary to avoid skew between the version of the Dart VM used in
+### the flutter_runner and the version of the Dart SDK and VM used by the
+### Flutter toolchain. See
+### https://github.com/flutter/flutter/wiki/Compiling-the-engine#important-dart-version-synchronization-on-fuchsia
+### for more details.
+###
+### Example:
+###   $ ./branch_from_fuchsia.sh my_new_feature_branch
+
+source "$(cd "$(dirname "${BASH_SOURCE[0]}")" >/dev/null 2>&1 && pwd)"/lib/vars.sh || exit $?
+
+ensure_fuchsia_dir
+
+engine-info "Syncing to Fuchsia's checkout of the Flutter engine."
+source "$(cd "$(dirname "${BASH_SOURCE[0]}")" >/dev/null 2>&1 && pwd)"/sync_to_fuchsia.sh || exit $?
+
+engine-info "Creating new branch '$1'."
+git checkout -b $1
+if [ $? -ne 0 ]
+then
+    engine-error "Failed to create new branch '$1'. Restoring previous checkout."
+    git checkout -
+    exit $?
+fi
diff --git a/engine/src/flutter/tools/fuchsia/devshell/lib/vars.sh b/engine/src/flutter/tools/fuchsia/devshell/lib/vars.sh
index e77b1313163..44467f8d728 100644
--- a/engine/src/flutter/tools/fuchsia/devshell/lib/vars.sh
+++ b/engine/src/flutter/tools/fuchsia/devshell/lib/vars.sh
@@ -29,6 +29,15 @@ function engine-is-stderr-tty {
   [[ -t 2 ]]
 }
 
+# engine-info prints a line to stderr with a green INFO: prefix.
+function engine-info {
+  if engine-is-stderr-tty; then
+    echo -e >&2 "\033[1;32mINFO:\033[0m $*"
+  else
+    echo -e >&2 "INFO: $*"
+  fi
+}
+
 # engine-error prints a line to stderr with a red ERROR: prefix.
 function engine-error {
   if engine-is-stderr-tty; then
diff --git a/engine/src/flutter/tools/fuchsia/devshell/sync_to_fuchsia.sh b/engine/src/flutter/tools/fuchsia/devshell/sync_to_fuchsia.sh
new file mode 100755
index 00000000000..cb7fe78b41b
--- /dev/null
+++ b/engine/src/flutter/tools/fuchsia/devshell/sync_to_fuchsia.sh
@@ -0,0 +1,21 @@
+#!/bin/bash
+# Copyright 2013 The Flutter Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+#
+### Checks out the version of Flutter engine in your Fuchsia source tree.
+### This is necessary to avoid skew between the version of the Dart VM used in
+### the flutter_runner and the version of the Dart SDK and VM used by the
+### Flutter toolchain. See
+### https://github.com/flutter/flutter/wiki/Compiling-the-engine#important-dart-version-synchronization-on-fuchsia
+### for more details.
+###
+### Example:
+###   $ ./sync_to_fuchsia.sh
+
+source "$(cd "$(dirname "${BASH_SOURCE[0]}")" >/dev/null 2>&1 && pwd)"/lib/vars.sh || exit $?
+
+ensure_fuchsia_dir
+
+fuchsia_flutter_git_revision="$(cat $FUCHSIA_DIR/integration/jiri.lock | grep -A 1 "\"package\": \"flutter/fuchsia\"" | grep "git_revision" | tr ":" "\n" | sed -n 3p | tr "\"" "\n" | sed -n 1p)"
+git checkout $fuchsia_flutter_git_revision