From 03da2144985c5d4b6a82091b9987eff3f2ca6140 Mon Sep 17 00:00:00 2001
From: Ian Jackson <ijackson@chiark.greenend.org.uk>
Date: Sat, 25 Jul 2020 18:43:34 +0100
Subject: [PATCH] Option --man[ual] to show the manual

Closes #8

Signed-off-by: Ian Jackson <ijackson@chiark.greenend.org.uk>
---
 README.md     |  3 +++
 nailing-cargo | 10 ++++++++++
 2 files changed, 13 insertions(+)

diff --git a/README.md b/README.md
index a2602a8..b1946b0 100644
--- a/README.md
+++ b/README.md
@@ -365,6 +365,9 @@ Options
 
   * `-h` | `--help`: Print usage summary.
 
+  * `--man` | `--manual`: Format this manual into html using `pandoc`
+    and display it with `w3m`.
+
 Environment of the build command
 --------------------------------
 
diff --git a/nailing-cargo b/nailing-cargo
index 22d5dd5..98436be 100755
--- a/nailing-cargo
+++ b/nailing-cargo
@@ -25,6 +25,7 @@ options:
 
   -T<arch>  --target=<arch>       Specify target architecture
   -h --help                       Print this message
+  --man --manual                  Display complete manual (in w3m)
 
   -s<subcommand>                  Treat command as `cargo <subcommand>`
   --subcommand-props=<prop>,...   Override command props (see docs)
@@ -105,6 +106,13 @@ sub print_usage () {
   exit 0;
 }
 
+sub show_manual () {
+  my $manual = ($base_path // '.').'/README.md';
+  stat $manual or die "$self: manual not found at $manual: $!\n";;
+  exec 'sh','-ec', 'pandoc -- "$1" 2>&1 | w3m -T text/html', '--', $manual;
+  die "$self: exec sh failed: $!";
+}
+
 sub read_or_enoent ($) {
   my ($fn) = @_;
   if (!open R, '<', $fn) {
@@ -895,6 +903,8 @@ sub parse_args () {
       }
     } elsif (s{^--help$}{}) {
       print_usage();
+    } elsif (s{^--man(?:ual)?$}{}) {
+      show_manual();
     } elsif (s{^--target=}{}) {
       $target = $_;
     } elsif (m{^--(on|off)line$}) {
-- 
2.30.2