From a3c4eb096456673b48f4fc35b76097d67e022141 Mon Sep 17 00:00:00 2001
From: Eelco Dolstra <eelco.dolstra@logicblox.com>
Date: Thu, 1 Oct 2015 16:53:07 +0200
Subject: [PATCH] nix-prefetch-url: $PRINT_PATH -> --print-path

---
 doc/manual/command-ref/nix-prefetch-url.xml | 27 +++++++++++++--------
 src/nix-prefetch-url/nix-prefetch-url.cc    |  8 ++++--
 2 files changed, 23 insertions(+), 12 deletions(-)

diff --git a/doc/manual/command-ref/nix-prefetch-url.xml b/doc/manual/command-ref/nix-prefetch-url.xml
index 5d1ab6931..0f24bef39 100644
--- a/doc/manual/command-ref/nix-prefetch-url.xml
+++ b/doc/manual/command-ref/nix-prefetch-url.xml
@@ -3,7 +3,7 @@
       xmlns:xi="http://www.w3.org/2001/XInclude"
       version="5.0"
       xml:id="sec-nix-prefetch-url">
-  
+
 <refmeta>
   <refentrytitle>nix-prefetch-url</refentrytitle>
   <manvolnum>1</manvolnum>
@@ -54,8 +54,8 @@ error if signaled if the actual hash of the file does not match the
 specified hash.</para>
 
 <para>This command prints the hash on standard output.  Additionally,
-if the environment variable <envar>PRINT_PATH</envar> is set, the path
-of the downloaded file in the Nix store is also printed.</para>
+if the option <option>--print-path</option> is used, the path of the
+downloaded file in the Nix store is also printed.</para>
 
 </refsection>
 
@@ -63,7 +63,7 @@ of the downloaded file in the Nix store is also printed.</para>
 <refsection><title>Options</title>
 
 <variablelist>
-  
+
   <varlistentry><term><option>--type</option> <replaceable>hashAlgo</replaceable></term>
 
     <listitem><para>Use the specified cryptographic hash algorithm,
@@ -73,6 +73,13 @@ of the downloaded file in the Nix store is also printed.</para>
 
   </varlistentry>
 
+  <varlistentry><term><option>--print-path</option></term>
+
+    <listitem><para>Print the store path of the downloaded file on
+    standard output.</para></listitem>
+
+  </varlistentry>
+
 </variablelist>
 
 </refsection>
@@ -81,14 +88,14 @@ of the downloaded file in the Nix store is also printed.</para>
 <refsection><title>Examples</title>
 
 <screen>
-$ nix-prefetch-url ftp://ftp.nluug.nl/pub/gnu/make/make-3.80.tar.bz2
-0bbd1df101bc0294d440471e50feca71
+$ nix-prefetch-url ftp://ftp.gnu.org/pub/gnu/hello/hello-2.10.tar.gz
+0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i
 
-$ PRINT_PATH=1 nix-prefetch-url ftp://ftp.nluug.nl/pub/gnu/make/make-3.80.tar.bz2
-0bbd1df101bc0294d440471e50feca71
-/nix/store/wvyz8ifdn7wyz1p3pqyn0ra45ka2l492-make-3.80.tar.bz2</screen>
+$ nix-prefetch-url --print-path mirror://gnu/hello/hello-2.10.tar.gz
+0ssi1wpaf7plaswqqjwigppsg5fyh99vdlb9kzl7c9lng89ndq1i
+/nix/store/3x7dwzq014bblazs7kq20p9hyzz0qh8g-hello-2.10.tar.gz</screen>
 
 </refsection>
 
-    
+
 </refentry>
diff --git a/src/nix-prefetch-url/nix-prefetch-url.cc b/src/nix-prefetch-url/nix-prefetch-url.cc
index bd52df1c7..cb6078fca 100644
--- a/src/nix-prefetch-url/nix-prefetch-url.cc
+++ b/src/nix-prefetch-url/nix-prefetch-url.cc
@@ -48,6 +48,7 @@ int main(int argc, char * * argv)
         HashType ht = htSHA256;
         std::vector<string> args;
         Strings searchPath;
+        bool printPath = getEnv("PRINT_PATH") != "";
 
         parseCmdLine(argc, argv, [&](Strings::iterator & arg, const Strings::iterator & end) {
             if (*arg == "--help")
@@ -60,6 +61,8 @@ int main(int argc, char * * argv)
                 if (ht == htUnknown)
                     throw UsageError(format("unknown hash type ‘%1%’") % s);
             }
+            else if (*arg == "--print-path")
+                printPath = true;
             else if (parseSearchPathArg(arg, end, searchPath))
                 ;
             else if (*arg != "" && arg->at(0) == '-')
@@ -123,10 +126,11 @@ int main(int argc, char * * argv)
             storePath = store->addToStore(name, tmpFile, false, ht);
         }
 
-        printMsg(lvlInfo, format("path is ‘%1%’") % storePath);
+        if (!printPath)
+            printMsg(lvlInfo, format("path is ‘%1%’") % storePath);
 
         std::cout << printHash16or32(hash) << std::endl;
-        if (getEnv("PRINT_PATH") != "")
+        if (printPath)
             std::cout << storePath << std::endl;
     });
 }