Bash completion support for --gtest_* and --test-launcher-* cmdline switches.

tools/bash-completion

 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 # Flag completion rule for bash.
 # To load in your shell, "source path/to/this/file".
 
 chrome_source=$(cd $(dirname $BASH_SOURCE)/.. && pwd)
 
 _chrome_flag() {
     local cur targets
     cur="${COMP_WORDS[COMP_CWORD]}"
     targets=$(cd $chrome_source; \
         git ls-files '*switches*' | \
         xargs sed -ne 's/^[^/]*"\([^" /]\{1,\}\)".*/--\1/p')
     COMPREPLY=($(compgen -W "$targets" -- "$cur"))
     return 0
 }
 
+_gtest_flag() {
+    local cur gtest_flags launcher_flags
+    cur="${COMP_WORDS[COMP_CWORD]}"
+    gtest_flags=$(sed -ne 's/^.*FromGTestEnv("\([^" /]\+\)".*$/--gtest_\1/p' \
+      "$chrome_source/testing/gtest/src/gtest.cc")
+    chrome_test_launcher_flags=$(sed -ne 's/^[^/]*"\([^" /]\{1,\}\)".*/--\1/p' \
+      "$chrome_source/base/test/test_switches.cc")
+    COMPREPLY=($(
+      compgen -W "$gtest_flags $chrome_test_launcher_flags" -- "$cur"))
+    return 0
+}
+
 complete -F _chrome_flag google-chrome
 complete -F _chrome_flag chrome
 if [ $(uname) = "Darwin" ]
 then
   complete -F _chrome_flag Chromium
 fi
+
+for gtest_test_executable in $(
+  cd $chrome_source;
+  git ls-files '*/BUILD.gn' | xargs sed -ne 's/^test("\([^"]\+\)").*$/\1/p'
+); do
+  complete -F _gtest_flag $gtest_test_executable
+done