Bash completion for flags (#254)

Signed-off-by: Mabel Zhang <mabel@openrobotics.org>
Signed-off-by: Louise Poubel <louise@openrobotics.org>

Co-authored-by: Louise Poubel <louise@openrobotics.org>

Author: mabelzhang

CMakeLists.txt

@@ -16,6 +16,12 @@ find_package(ignition-cmake2 2.8.0 REQUIRED)
 #============================================================================
 ign_configure_project()
 
+if (UNIX AND NOT APPLE)
+  set (EXTRA_TEST_LIB_DEPS stdc++fs)
+else()
+  set (EXTRA_TEST_LIB_DEPS)
+endif()
+
 #============================================================================
 # Set project-specific options
 #============================================================================
@@ -69,8 +75,11 @@ ign_find_package(ignition-math6 REQUIRED)
 set(IGN_MATH_VER ${ignition-math6_VERSION_MAJOR})
 
 #--------------------------------------
-# Find if ign command is available
+# Find if command is available. This is used to enable tests.
+# Note that CLI files are installed regardless of whether the dependency is
+# available during build time
 find_program(HAVE_IGN_TOOLS ign)
+set(IGN_TOOLS_VER 1)
 
 #--------------------------------------
 # Find Tinyxml2

src/cmd/CMakeLists.txt

@@ -42,3 +42,17 @@ file(GENERATE
 
 # Install the ruby command line library in an unversioned location.
 install(FILES ${cmd_script_generated} DESTINATION lib/ruby/ignition)
+
+
+#===============================================================================
+# Bash completion
+
+# Tack version onto and install the bash completion script
+configure_file(
+  "msgs.bash_completion.sh"
+    "${CMAKE_CURRENT_BINARY_DIR}/msgs${PROJECT_VERSION_MAJOR}.bash_completion.sh" @ONLY)
+install(
+  FILES
+    ${CMAKE_CURRENT_BINARY_DIR}/msgs${PROJECT_VERSION_MAJOR}.bash_completion.sh
+  DESTINATION
+    ${CMAKE_INSTALL_PREFIX}/${CMAKE_INSTALL_DATAROOTDIR}/gz/gz${IGN_TOOLS_VER}.completion.d)

src/cmd/msgs.bash_completion.sh

@@ -0,0 +1,52 @@
+#!/usr/bin/env bash
+#
+# Copyright (C) 2022 Open Source Robotics Foundation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+# bash tab-completion
+
+# This is a per-library function definition, used in conjunction with the
+# top-level entry point in ign-tools.
+
+GZ_MSGS_COMPLETION_LIST="
+  -i --info
+  -l --list
+  -h --help
+  --force-version
+  --versions
+"
+
+function _gz_msg
+{
+  if [[ ${COMP_WORDS[COMP_CWORD]} == -* ]]; then
+    # Specify options (-*) word list for this subcommand
+    COMPREPLY=($(compgen -W "$GZ_MSGS_COMPLETION_LIST" \
+      -- "${COMP_WORDS[COMP_CWORD]}" ))
+    return
+  else
+    # Just use bash default auto-complete, because we never have two
+    # subcommands in the same line. If that is ever needed, change here to
+    # detect subsequent subcommands
+    COMPREPLY=($(compgen -o default -- "${COMP_WORDS[COMP_CWORD]}"))
+    return
+  fi
+}
+
+function _gz_msgs_flags
+{
+  for word in $GZ_MSGS_COMPLETION_LIST; do
+    echo "$word"
+  done
+}

tools/CMakeLists.txt

@@ -12,7 +12,10 @@ if (MSVC)
   list(REMOVE_ITEM test_sources ign_TEST.cc)
 endif()
 
-
 if (HAVE_IGN_TOOLS)
-  ign_build_tests(TYPE UNIT SOURCES ${test_sources})
+  ign_build_tests(
+    TYPE UNIT
+    SOURCES ${test_sources}
+    LIB_DEPS
+      ${EXTRA_TEST_LIB_DEPS})
 endif ()

tools/ign_TEST.cc

@@ -15,6 +15,8 @@
  *
 */
 
+#include <filesystem>
+#include <fstream>
 #include <string>
 #include <gtest/gtest.h>
 #include <ignition/msgs/config.hh>
@@ -89,6 +91,36 @@ TEST(CmdLine, MsgInfo)
     << output;
 }
 
+/////////////////////////////////////////////////
+TEST(CmdLine, MsgHelpVsCompletionFlags)
+{
+  // Flags in help message
+  auto helpOutput = custom_exec_str("ign msg --help --force-version "
+    + g_version);
+
+  // Call the output function in the bash completion script
+  std::filesystem::path scriptPath = PROJECT_SOURCE_PATH;
+  scriptPath = scriptPath / "src" / "cmd" / "msgs.bash_completion.sh";
+
+  // Equivalent to:
+  // sh -c "bash -c \". /path/to/msgs.bash_completion.sh; _gz_msgs_flags\""
+  std::string cmd = "bash -c \". " + scriptPath.string() + "; _gz_msgs_flags\"";
+  std::string scriptOutput = custom_exec_str(cmd);
+
+  // Tokenize script output
+  std::istringstream iss(scriptOutput);
+  std::vector<std::string> flags((std::istream_iterator<std::string>(iss)),
+    std::istream_iterator<std::string>());
+
+  EXPECT_GT(flags.size(), 0u);
+
+  // Match each flag in script output with help message
+  for (std::string flag : flags)
+  {
+    EXPECT_NE(std::string::npos, helpOutput.find(flag)) << helpOutput;
+  }
+}
+
 /////////////////////////////////////////////////
 /// Main
 int main(int argc, char **argv)