From 6e9364ab50082fba74fd0a0a733993d49075756e Mon Sep 17 00:00:00 2001
From: Fabian Homborg <FHomborg@gmail.com>
Date: Mon, 14 Dec 2020 19:25:55 +0100
Subject: [PATCH] fish_indent: Change --debug-level to --debug with flog
 categories

The "debug-level" flag makes little sense since we have no more
debug *levels* left.
---
 doc_src/cmds/fish_indent.rst       |  4 +++-
 share/completions/fish_indent.fish |  3 ++-
 src/fish_indent.cpp                | 31 +++++++++++++++++++++++++++---
 3 files changed, 33 insertions(+), 5 deletions(-)

diff --git a/doc_src/cmds/fish_indent.rst b/doc_src/cmds/fish_indent.rst
index 7572d6358..fa5a23eb8 100644
--- a/doc_src/cmds/fish_indent.rst
+++ b/doc_src/cmds/fish_indent.rst
@@ -30,6 +30,8 @@ The following options are available:
 
 - ``--html`` outputs HTML, which supports syntax highlighting if the appropriate CSS is defined. The CSS class names are the same as the variable names, such as ``fish_color_command``.
 
-- ``-d`` or ``--debug-level=DEBUG_LEVEL`` enables debug output and specifies a verbosity level. Defaults to 0.
+- ``-d`` or ``--debug=DEBUG_CATEGORIES`` enable debug output and specify a pattern for matching debug categories. See :ref:`Debugging <debugging-fish>` in :ref:`fish(1) <cmd-fish>` for details.
+
+- ``-o`` or ``--debug-output=DEBUG_FILE`` specify a file path to receive the debug output, including categories and ``fish_trace``. The default is stderr.
 
 - ``--dump-parse-tree`` dumps information about the parsed statements to stderr. This is likely to be of interest only to people working on the fish source code.
diff --git a/share/completions/fish_indent.fish b/share/completions/fish_indent.fish
index 17deb50e9..50cbf0532 100644
--- a/share/completions/fish_indent.fish
+++ b/share/completions/fish_indent.fish
@@ -4,6 +4,7 @@ complete -c fish_indent -s i -l no-indent -d 'Do not indent output, only reforma
 complete -c fish_indent -l ansi -d 'Colorize the output using ANSI escape sequences'
 complete -c fish_indent -l html -d 'Output in HTML format'
 complete -c fish_indent -s w -l write -d 'Write to file'
-complete -c fish_indent -s d -l debug-level -x -d 'Enable debug at specified verbosity level'
+complete -c fish_indent -s d -l debug -x -d 'Enable debug at specified verbosity level'
+complete -c fish_indent -s o -l debug-output -d "Where to direct debug output to" -rF
 complete -c fish_indent -s D -l debug-stack-frames -x -d 'Specify how many stack frames to display in debug messages'
 complete -c fish_indent -l dump-parse-tree -d 'Dump information about parsed statements to stderr'
diff --git a/src/fish_indent.cpp b/src/fish_indent.cpp
index faa4729c6..cdbca5db2 100644
--- a/src/fish_indent.cpp
+++ b/src/fish_indent.cpp
@@ -858,9 +858,12 @@ int main(int argc, char *argv[]) {
     } output_type = output_type_plain_text;
     const char *output_location = "";
     bool do_indent = true;
+    // File path for debug output.
+    std::string debug_output;
 
     const char *short_opts = "+d:hvwicD:";
-    const struct option long_opts[] = {{"debug-level", required_argument, nullptr, 'd'},
+    const struct option long_opts[] = {{"debug", required_argument, nullptr, 'd'},
+                                       {"debug-output", required_argument, nullptr, 'o'},
                                        {"debug-stack-frames", required_argument, nullptr, 'D'},
                                        {"dump-parse-tree", no_argument, nullptr, 'P'},
                                        {"no-indent", no_argument, nullptr, 'i'},
@@ -922,8 +925,12 @@ int main(int argc, char *argv[]) {
                 if (tmp >= 0 && tmp <= 10 && !*end && !errno) {
                     debug_level = static_cast<int>(tmp);
                 } else {
-                    std::fwprintf(stderr, _(L"Invalid value '%s' for debug-level flag"), optarg);
-                    exit(1);
+                    activate_flog_categories_by_pattern(str2wcstring(optarg));
+                }
+                for (auto cat : get_flog_categories()) {
+                    if (cat->enabled) {
+                        printf("Debug enabled for category: %ls\n", cat->name);
+                    }
                 }
                 break;
             }
@@ -932,6 +939,10 @@ int main(int argc, char *argv[]) {
                 // Either remove it or make it work with FLOG.
                 break;
             }
+            case 'o': {
+                debug_output = optarg;
+                break;
+            }
             default: {
                 // We assume getopt_long() has already emitted a diagnostic msg.
                 exit(1);
@@ -942,6 +953,20 @@ int main(int argc, char *argv[]) {
     argc -= optind;
     argv += optind;
 
+    // Direct any debug output right away.
+    FILE *debug_output_file = nullptr;
+    if (!debug_output.empty()) {
+        debug_output_file = fopen(debug_output.c_str(), "w");
+        if (!debug_output_file) {
+            fprintf(stderr, "Could not open file %s\n", debug_output.c_str());
+            perror("fopen");
+            exit(-1);
+        }
+        set_cloexec(fileno(debug_output_file));
+        setlinebuf(debug_output_file);
+        set_flog_output_file(debug_output_file);
+    }
+
     int retval = 0;
 
     wcstring src;