* Unify the treatment of sources copied to the store, and recursive

  SHA-256 outputs of fixed-output derivations.  I.e. they now produce
  the same store path:

  $ nix-store --add x
  /nix/store/j2fq9qxvvxgqymvpszhs773ncci45xsj-x

  $ nix-store --add-fixed --recursive sha256 x
  /nix/store/j2fq9qxvvxgqymvpszhs773ncci45xsj-x

  the latter being the same as the path that a derivation

    derivation {
      name = "x";
      outputHashAlgo = "sha256";
      outputHashMode = "recursive";
      outputHash = "...";
      ...
    };

  produces.

  This does change the output path for such fixed-output derivations.
  Fortunately they are quite rare.  The most common use is fetchsvn
  calls with SHA-256 hashes.  (There are a handful of those is
  Nixpkgs, mostly unstable development packages.)
  
* Documented the computation of store paths (in store-api.cc).

3 files changed, 51 insertions, 7 deletions

diff --git a/tests/add.sh b/tests/add.sh
index 83092b26c143..7ea4cb6d6a99 100644
--- a/tests/add.sh
+++ b/tests/add.sh
@@ -1,13 +1,28 @@
 source common.sh
 
-file=./add.sh
+path1=$($nixstore --add ./dummy)
+echo $path1
 
-path=$($nixstore --add $file)
+path2=$($nixstore --add-fixed sha256 --recursive ./dummy)
+echo $path2
 
-echo $path
+if test "$path1" != "$path2"; then
+    echo "nix-store --add and --add-fixed mismatch"
+    exit 1
+fi    
 
-hash=$($nixstore -q --hash $path)
+path3=$($nixstore --add-fixed sha256 ./dummy)
+echo $path3
+test "$path1" != "$path3" || exit 1
 
-echo $hash
+path4=$($nixstore --add-fixed sha1 --recursive ./dummy)
+echo $path4
+test "$path1" != "$path4" || exit 1
 
-test "$hash" = "sha256:$($nixhash --type sha256 --base32 $file)"
+hash1=$($nixstore -q --hash $path1)
+echo $hash1
+
+hash2=$($nixhash --type sha256 --base32 ./dummy)
+echo $hash2
+
+test "$hash1" = "sha256:$hash2"
diff --git a/tests/fixed.nix.in b/tests/fixed.nix.in
index 5d364eb39ea5..ad5306cf6ac4 100644
--- a/tests/fixed.nix.in
+++ b/tests/fixed.nix.in
@@ -20,7 +20,6 @@ rec {
     (f ./fixed.builder1.sh "flat" "sha1" "a0b65939670bc2c010f4d5d6a0b3e4e4590fb92b")
     (f ./fixed.builder2.sh "recursive" "md5" "3670af73070fa14077ad74e0f5ea4e42")
     (f ./fixed.builder2.sh "recursive" "sha1" "vw46m23bizj4n8afrc0fj19wrp7mj3c0")
-    (f ./fixed.builder2.sh "recursive" "sha256" "1ixr6yd3297ciyp9im522dfxpqbkhcw0pylkb2aab915278fqaik")
   ];
 
   good2 = [
@@ -30,6 +29,9 @@ rec {
     (f ./fixed.builder2.sh "flat" "md5" "8ddd8be4b179a529afa5f2ffae4b9858")
   ];
 
+  sameAsAdd =
+    f ./fixed.builder2.sh "recursive" "sha256" "1ixr6yd3297ciyp9im522dfxpqbkhcw0pylkb2aab915278fqaik";
+
   bad = [
     (f ./fixed.builder1.sh "flat" "md5" "0ddd8be4b179a529afa5f2ffae4b9858")
   ];
diff --git a/tests/fixed.sh b/tests/fixed.sh
index 72038adfce83..9d5de2929b6f 100644
--- a/tests/fixed.sh
+++ b/tests/fixed.sh
@@ -34,3 +34,30 @@ clearStore
 drvs=$($nixinstantiate fixed.nix -A parallelSame)
 echo $drvs
 $nixstore -r $drvs -j2
+
+# Fixed-output derivations with a recursive SHA-256 hash should
+# produce the same path as "nix-store --add".
+echo 'testing sameAsAdd...'
+drv=$($nixinstantiate fixed.nix -A sameAsAdd)
+echo $drv
+out=$($nixstore -r $drv)
+echo $out
+
+# This is what fixed.builder2 produces...
+rm -rf $TEST_ROOT/fixed
+mkdir $TEST_ROOT/fixed
+mkdir $TEST_ROOT/fixed/bla
+echo "Hello World!" > $TEST_ROOT/fixed/foo
+ln -s foo $TEST_ROOT/fixed/bar
+
+out2=$($nixstore --add $TEST_ROOT/fixed)
+echo $out2
+test "$out" = "$out2" || exit 1
+
+out3=$($nixstore --add-fixed --recursive sha256 $TEST_ROOT/fixed)
+echo $out3
+test "$out" = "$out3" || exit 1
+
+out4=$($nixstore --print-fixed-path --recursive sha256 "1ixr6yd3297ciyp9im522dfxpqbkhcw0pylkb2aab915278fqaik" fixed)
+echo $out4
+test "$out" = "$out4" || exit 1