nixos-option: enable all flags by default and make output a bit readable cc @nbp

nixos/doc/manual/man-nixos-option.xml

@@ -17,11 +17,6 @@
 <refsynopsisdiv>
   <cmdsynopsis>
     <command>nixos-option</command>
-    <group choice="opt">
-      <option>-v</option>
-      <option>-d</option>
-      <option>-l</option>
-    </group>
     <arg choice='plain'><replaceable>option.name</replaceable></arg>
   </cmdsynopsis>
 </refsynopsisdiv>
@@ -31,50 +26,13 @@
 
 <para>This command evaluates the configuration specified in
 <filename>/etc/nixos/configuration.nix</filename> and returns the properties
-of the option name given as argument.  By default, it returns the value of
+of the option name given as argument.</para>
-the option.</para>
 
 <para>When the option name is not an option, the command prints the list of
 attributes contained in the attribute set.</para>
 
 </refsection>
 
-<refsection><title>Options</title>
-
-<para>This command accepts the following options:</para>
-
-<variablelist>
-
-  <varlistentry>
-    <term><option>--value</option>, <option>-v</option></term>
-    <listitem>
-      <para>Returns the value of the option.  This is the default operation
-      if no other options are defined.</para>
-    </listitem>
-  </varlistentry>
-
-  <varlistentry>
-    <term><option>--description</option>, <option>-d</option></term>
-    <listitem>
-      <para>Return the default value, the example and the description of the
-      option when available.</para>
-    </listitem>
-  </varlistentry>
-
-  <varlistentry>
-    <term><option>--lookup</option>, <option>-l</option></term>
-    <listitem>
-      <para>Return the locations where the option is declared and where it
-      is defined.  This is extremely useful to find sources of errors in
-      your configuration.</para>
-    </listitem>
-  </varlistentry>
-
-</variablelist>
-
-</refsection>
-
-
 <refsection><title>Environment</title>
 
 <variablelist>
@@ -103,27 +61,21 @@ grub
 initScript
 
 $ nixos-option boot.loader.grub.enable
-true</screen></para>
+Value:
+true
 
-<para>Prints option information:
+Default: 
+true
 
-<screen>$ nixos-option -d networking.hostName
-Default: "nixos"
 Description:
-The name of the machine. Leave it empty if you want to obtain
+Whether to enable the GNU GRUB boot loader.
-it from a DHCP server (if using DHCP).</screen></para>
 
-<para>Find the locations which are declaring and defining an option:
-
-<screen>$ nixos-option -l hardware.firmware
 Declared by:
-  /mnt/data/nix-sources/nixos/modules/services/hardware/udev.nix
+  "/path/to/nixpkgs/nixos/modules/system/boot/loader/grub/grub.nix"
 
 Defined by:
-  /path/to/nixpkgs/nixos/modules/system/boot/kernel.nix
+  "/nix/var/nix/profiles/per-user/root/channels/nixos/nixpkgs/nixos/modules/system/boot/loader/grub/grub.nix"
-  /path/to/nixpkgs/nixos/modules/hardware/network/rt73.nix
+</screen></para>
-  /path/to/nixpkgs/nixos/modules/hardware/network/intel-3945abg.nix
-  /path/to/nixpkgs/nixos/modules/hardware/network/intel-2200bg.nix</screen></para>
 
 </refsection>
 

nixos/modules/installer/tools/nixos-option.sh

@@ -11,9 +11,6 @@ usage () {
 # Process Arguments #
 #####################
 
-desc=false
-defs=false
-value=false
 xml=false
 verbose=false
 
@@ -24,14 +21,11 @@ for arg; do
   if test -z "$argfun"; then
     case $arg in
       -*)
-        longarg=""
         sarg="$arg"
+        longarg=""
         while test "$sarg" != "-"; do
           case $sarg in
             --*) longarg=$arg; sarg="--";;
-            -d*) longarg="$longarg --description";;
-            -v*) longarg="$longarg --value";;
-            -l*) longarg="$longarg --lookup";;
             -*) usage;;
           esac
           # remove the first letter option
@@ -42,9 +36,6 @@ for arg; do
     esac
     for larg in $longarg; do
       case $larg in
-        --description) desc=true;;
-        --value) value=true;;
-        --lookup) defs=true;;
         --xml) xml=true;;
         --verbose) verbose=true;;
         --help) usage;;
@@ -67,16 +58,6 @@ for arg; do
   fi
 done
 
-if $xml; then
-  value=true
-  desc=true
-  defs=true
-fi
-
-if ! $defs && ! $desc; then
-  value=true
-fi
-
 if $verbose; then
   set -x
 else
@@ -95,8 +76,7 @@ evalAttr(){
   local prefix="$1"
   local strict="$2"
   local suffix="$3"
-  echo "(import <nixos> {}).$prefix${option:+.$option}${suffix:+.$suffix}" |
+  echo "(import <nixos> {}).$prefix${option:+.$option}${suffix:+.$suffix}" | evalNix ${strict:+--strict}
-    evalNix ${strict:+--strict}
 }
 
 evalOpt(){
@@ -189,35 +169,35 @@ EOF
 fi
 
 if test "$(evalOpt "_type" 2> /dev/null)" = '"option"'; then
-  $value && evalCfg 1
+  echo "Value:"
+  evalCfg 1
 
-  if $desc; then
+  echo
-    $value && echo;
 
-    if default=$(evalOpt "default" - 2> /dev/null); then
+  echo "Default:"
-      echo "Default: $default"
+  if default=$(evalOpt "default" - 2> /dev/null); then
-    else
+    echo "$default"
-      echo "Default: <None>"
+  else
-    fi
+    echo "<None>"
-    if example=$(evalOpt "example" - 2> /dev/null); then
-      echo "Example: $example"
-    fi
-    echo "Description:"
-    eval printf $(evalOpt "description")
   fi
-
+  echo
-  if $defs; then
+  if example=$(evalOpt "example" - 2> /dev/null); then
-    $desc || $value && echo;
+    echo "Example: $example"
-
-    printPath () { echo "  $1"; }
-
-    echo "Declared by:"
-    nixMap printPath "$(findSources "declarations")"
-    echo ""
-    echo "Defined by:"
-    nixMap printPath "$(findSources "files")"
-    echo ""
   fi
+  echo "Description:"
+  echo
+  eval printf $(evalOpt "description")
+
+  echo $desc;
+
+  printPath () { echo "  $1"; }
+
+  echo "Declared by:"
+  nixMap printPath "$(findSources "declarations")"
+  echo
+  echo "Defined by:"
+  nixMap printPath "$(findSources "files")"
+  echo
 
 else
   # echo 1>&2 "Warning: This value is not an option."