bash completion

.gitignore

@@ -7,6 +7,7 @@ subprojects/CLI11-*
 subprojects/curl-*
 subprojects/fmt-*
 subprojects/packagecache
+subprojects/range-v3-*
 subprojects/spdlog-*
 subprojects/sqlite-amalgamation-*
 subprojects/nlohmann_json-*

meson.build

@@ -26,6 +26,7 @@ catch_dep = subproject('catch2', default_options: ['werror=false', 'warning_leve
 cli11_dep = subproject('cli11', default_options: ['werror=false', 'warning_level=0']).get_variable('CLI11_dep')
 fmt_dep   = subproject('fmt', default_options: ['werror=false', 'warning_level=0']).get_variable('fmt_dep')
 json_dep = subproject('nlohmann_json', default_options: ['werror=false', 'warning_level=0']).get_variable('nlohmann_json_dep')
+range_dep   = subproject('range-v3', default_options: ['werror=false', 'warning_level=0']).get_variable('range_dep')
 spdlog_dep   = subproject('spdlog', default_options: ['werror=false', 'warning_level=0','std_format=disabled','external_fmt=enabled']).get_variable('spdlog_dep')
 sqlite3_dep = subproject('sqlite3', default_options: ['werror=false', 'warning_level=0']).get_variable('sqlite3_dep')
 subproject('curl', default_options: ['werror=false', 'warning_level=0', 'tests=disabled', 'unittests=disabled', 'tool=disabled'])
@@ -62,7 +63,7 @@ lib_inc = include_directories('src')
 
 lib_dep = declare_dependency(
         sources: lib_src,
-        dependencies: [curl_dep, sqlite3_dep, fmt_dep, spdlog_dep, json_dep, barkeep_dep],
+        dependencies: [curl_dep, sqlite3_dep, fmt_dep, range_dep, spdlog_dep, json_dep, barkeep_dep],
         include_directories: lib_inc
 )
 
@@ -86,12 +87,13 @@ if uenv_cli
             'src/cli/status.cpp',
             'src/cli/uenv.cpp',
             'src/cli/build.cpp',
+            'src/util/completion.cpp',
     ]
     uenv_dep = [sqlite3_dep]
 
     cli = executable('uenv',
             sources: uenv_src,
-            dependencies: [uenv_dep, lib_dep, fmt_dep, spdlog_dep, cli11_dep, barkeep_dep],
+            dependencies: [uenv_dep, lib_dep, fmt_dep, range_dep, spdlog_dep, cli11_dep, barkeep_dep],
             c_args: [
               '-DVERSION="@0@"'.format(version),
             ],

src/cli/uenv.cpp

@@ -10,6 +10,7 @@
 #include <uenv/parse.h>
 #include <uenv/repository.h>
 #include <util/color.h>
+#include <util/completion.h>
 #include <util/expected.h>
 #include <util/fs.h>
 
@@ -30,6 +31,7 @@ std::string help_footer();
 int main(int argc, char** argv) {
     uenv::global_settings settings;
     bool print_version = false;
+    bool generate_completion = false;
 
     // enable/disable color depending on NOCOLOR env. var and tty terminal
     // status.
@@ -45,6 +47,8 @@ int main(int argc, char** argv) {
         "enable color output");
     cli.add_flag("--repo", settings.repo_, "the uenv repository");
     cli.add_flag("--version", print_version, "print version");
+    cli.add_flag("--generate-completion", generate_completion,
+                 "generate bash completion script");
 
     cli.footer(help_footer);
 
@@ -92,6 +96,13 @@ int main(int argc, char** argv) {
         return 0;
     }
 
+    // generate bash completion script and exit if the --generate-completion
+    // flag was passed
+    if (generate_completion) {
+        fmt::print("{}", util::completion::create_completion(&cli));
+        return 0;
+    }
+
     // if a repo was not provided as a flag, look at environment variables
     if (!settings.repo_) {
         if (const auto p = uenv::default_repo_path()) {

src/util/completion.cpp

@@ -0,0 +1,96 @@
+#include <CLI/CLI.hpp>
+#include <fmt/core.h>
+#include <fmt/ranges.h>
+#include <range/v3/all.hpp>
+#include <ranges>
+
+#include <util/completion.h>
+
+namespace util {
+
+namespace completion {
+
+std::string get_prefix(CLI::App* cli) {
+    if (cli == nullptr)
+        return "";
+
+    CLI::App* parent = cli->get_parent();
+    return get_prefix(parent) + "_" + cli->get_name();
+}
+
+std::string traverse_subcommand_tree(CLI::App* cli) {
+    const auto subcommands = cli->get_subcommands({});
+    const auto options_non_positional = cli->get_options(
+        [](CLI::Option* option) { return option->nonpositional(); });
+
+    auto get_option_name = [](CLI::Option* option) {
+        return option->get_name();
+    };
+    auto get_subcommand_name = [](CLI::App* subcommand) {
+        return subcommand->get_name();
+    };
+
+    auto tmp1 = std::views::transform(options_non_positional, get_option_name);
+    auto tmp2 = std::views::transform(subcommands, get_subcommand_name);
+    auto completions = ranges::view::concat(tmp1, tmp2);
+
+    std::vector<std::string> func_command_str = {};
+    func_command_str.push_back(fmt::format(R"({}()
+{{
+    UENV_OPTS="{}"
+}}
+
+)",
+                                           get_prefix(cli),
+                                           fmt::join(completions, " ")));
+
+    auto func_subcommands_str =
+        std::views::transform(subcommands, traverse_subcommand_tree);
+
+    return fmt::format("{}{}", fmt::join(func_command_str, ""),
+                       fmt::join(func_subcommands_str, ""));
+}
+
+std::string create_completion(CLI::App* cli) {
+    std::string prefix_functions = traverse_subcommand_tree(cli);
+
+    std::string main_functions = R"(
+_uenv_completions()
+{
+    local cur prefix func_name UENV_OPTS
+
+    local -a COMP_WORDS_NO_FLAGS
+    local index=0
+    while [[ "$index" -lt "$COMP_CWORD" ]]
+    do
+        if [[ "${COMP_WORDS[$index]}" == [a-z]* ]]
+        then
+            COMP_WORDS_NO_FLAGS+=("${COMP_WORDS[$index]}")
+        fi
+        let index++
+    done
+    COMP_WORDS_NO_FLAGS+=("${COMP_WORDS[$COMP_CWORD]}")
+    local COMP_CWORD_NO_FLAGS=$((${#COMP_WORDS_NO_FLAGS[@]} - 1))
+
+    cur="${COMP_WORDS_NO_FLAGS[COMP_CWORD_NO_FLAGS]}"
+    prefix="_${COMP_WORDS_NO_FLAGS[*]:0:COMP_CWORD_NO_FLAGS}"
+    func_name="${prefix// /_}"
+    func_name="${func_name//-/_}"
+
+    UENV_OPTS=""
+    if typeset -f $func_name >/dev/null
+    then
+        $func_name
+    fi
+
+    COMPREPLY=($(compgen -W "${UENV_OPTS}" -- "${cur}"))
+}
+
+complete -F _uenv_completions uenv
+)";
+
+    return fmt::format("{}{}", prefix_functions, main_functions);
+}
+
+} // namespace completion
+} // namespace util

src/util/completion.h

@@ -0,0 +1,11 @@
+#pragma once
+
+#include <CLI/CLI.hpp>
+
+namespace util {
+namespace completion {
+
+std::string create_completion(CLI::App* cli);
+
+} // namespace completion
+} // namespace util

subprojects/range-v3.wrap

@@ -0,0 +1,13 @@
+[wrap-file]
+directory = range-v3-0.12.0
+source_url = https://github.com/ericniebler/range-v3/archive/0.12.0.tar.gz
+source_filename = range-v3-0.12.0.tar.gz
+source_hash = 015adb2300a98edfceaf0725beec3337f542af4915cec4d0b89fa0886f4ba9cb
+patch_filename = range-v3_0.12.0-2_patch.zip
+patch_url = https://wrapdb.mesonbuild.com/v2/range-v3_0.12.0-2/get_patch
+patch_hash = 0d0b2959701d42bb8c509eb770276de67e44b60ffba9af9cd66dad855700ec63
+source_fallback_url = https://github.com/mesonbuild/wrapdb/releases/download/range-v3_0.12.0-2/range-v3-0.12.0.tar.gz
+wrapdb_version = 0.12.0-2
+
+[provide]
+range-v3 = range_dep