From 1110dde8dcdb9979bfe9481ac8722f175640e035 Mon Sep 17 00:00:00 2001
From: Francesco Gazzetta <fgaz@fgaz.me>
Date: Sat, 23 Mar 2019 19:03:43 +0100
Subject: [PATCH 1/5] Clean up the filtering

---
 non-broken.nix | 29 ++++++++++++++---------------
 overlay.nix    | 22 ++++++++++++----------
 2 files changed, 26 insertions(+), 25 deletions(-)

diff --git a/non-broken.nix b/non-broken.nix
index b9a2cf9..35778c2 100644
--- a/non-broken.nix
+++ b/non-broken.nix
@@ -4,24 +4,23 @@
 # be added to the cache.
 { pkgs ? import <nixpkgs> {} }:
 
-let filterSet =
-      (f: g: s: builtins.listToAttrs
-        (map
-          (n: { name = n; value = builtins.getAttr n s; })
-          (builtins.filter
-            (n: f n && g (builtins.getAttr n s))
-            (builtins.attrNames s)
-          )
+let
+  filterSet =
+    (f: g: s: builtins.listToAttrs
+      (map
+        (n: { name = n; value = builtins.getAttr n s; })
+        (builtins.filter
+          (n: f n && g (builtins.getAttr n s))
+          (builtins.attrNames s)
         )
-      );
+      )
+    );
+  isReserved = n: builtins.elem n ["lib" "overlays" "modules"];
+  isBroken = p: ({ meta.broken = false; } // p).meta.broken;
 in filterSet
-     (n: !(n=="lib"||n=="overlays"||n=="modules")) # filter out non-packages
+     (n: !(isReserved n)) # filter out non-packages
      (p: (builtins.isAttrs p)
-       && !(
-             (builtins.hasAttr "meta" p)
-             && (builtins.hasAttr "broken" p.meta)
-             && (p.meta.broken)
-           )
+       && !(isBroken p)
      )
      (import ./default.nix { inherit pkgs; })
 
diff --git a/overlay.nix b/overlay.nix
index 082b038..bda4332 100644
--- a/overlay.nix
+++ b/overlay.nix
@@ -4,18 +4,20 @@
 
 self: super:
 
-let filterSet =
-      (f: g: s: builtins.listToAttrs
-        (map
-          (n: { name = n; value = builtins.getAttr n s; })
-          (builtins.filter
-            (n: f n && g (builtins.getAttr n s))
-            (builtins.attrNames s)
-          )
+let
+  filterSet =
+    (f: g: s: builtins.listToAttrs
+      (map
+        (n: { name = n; value = builtins.getAttr n s; })
+        (builtins.filter
+          (n: f n && g (builtins.getAttr n s))
+          (builtins.attrNames s)
         )
-      );
+      )
+    );
+  isReserved = n: builtins.elem n ["lib" "overlays" "modules"];
 in filterSet
-     (n: !(n=="lib"||n=="overlays"||n=="modules")) # filter out non-packages
+     (n: !(isReserved n)) # filter out non-packages
      (p: true) # all packages are ok
      (import ./default.nix { pkgs = super; })
 

From f751ec55c73b506faa023e7684cdc4a05bef9415 Mon Sep 17 00:00:00 2001
From: Francesco Gazzetta <fgaz@fgaz.me>
Date: Sat, 23 Mar 2019 19:05:19 +0100
Subject: [PATCH 2/5] Rename non-broken

---
 .travis.yml                     | 2 +-
 non-broken.nix => buildable.nix | 0
 2 files changed, 1 insertion(+), 1 deletion(-)
 rename non-broken.nix => buildable.nix (100%)

diff --git a/.travis.yml b/.travis.yml
index 66ece26..e1d6117 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -22,7 +22,7 @@ install:
  - travis_retry nix-channel --update
 
 script:
- - outs=$(nix-build non-broken.nix) && echo Produced $outs
+ - outs=$(nix-build buildable.nix) && echo Produced $outs
  - nix eval -f default.nix 'lib'
  - nix eval -f default.nix 'modules'
  - nix eval -f default.nix 'overlays'
diff --git a/non-broken.nix b/buildable.nix
similarity index 100%
rename from non-broken.nix
rename to buildable.nix

From 23f67915d12aaf0759b022a4c47b730b4687b7d2 Mon Sep 17 00:00:00 2001
From: Francesco Gazzetta <fgaz@fgaz.me>
Date: Sat, 23 Mar 2019 19:05:38 +0100
Subject: [PATCH 3/5] Only build free packages

---
 buildable.nix | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/buildable.nix b/buildable.nix
index 35778c2..21af140 100644
--- a/buildable.nix
+++ b/buildable.nix
@@ -17,10 +17,12 @@ let
     );
   isReserved = n: builtins.elem n ["lib" "overlays" "modules"];
   isBroken = p: ({ meta.broken = false; } // p).meta.broken;
+  isFree = p: ({ meta.license.free = true; } // p).meta.license.free;
 in filterSet
      (n: !(isReserved n)) # filter out non-packages
      (p: (builtins.isAttrs p)
        && !(isBroken p)
+       && isFree p
      )
      (import ./default.nix { inherit pkgs; })
 

From c57e61235d5b74fc7ef508d3ce4315e0842d6c31 Mon Sep 17 00:00:00 2001
From: Francesco Gazzetta <fgaz@fgaz.me>
Date: Sat, 23 Mar 2019 19:13:30 +0100
Subject: [PATCH 4/5] Wording

---
 buildable.nix | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/buildable.nix b/buildable.nix
index 21af140..9445e5f 100644
--- a/buildable.nix
+++ b/buildable.nix
@@ -1,6 +1,6 @@
-# This file filters out all the broken packages from your package set.
-# It's what gets built by CI, so if you correctly mark broken packages as
-# broken your CI will not try to build them and the non-broken packages will
+# This file filters out all the unbuildable packages from your package set.
+# It's what gets built by CI, so if you correctly mark broken/unfree packages
+# as such your CI will not try to build them and the buildable packages will
 # be added to the cache.
 { pkgs ? import <nixpkgs> {} }:
 

From 6ad0281a198f7084ce9857931ab99e119a3682c9 Mon Sep 17 00:00:00 2001
From: Francesco Gazzetta <fgaz@fgaz.me>
Date: Sat, 23 Mar 2019 19:23:02 +0100
Subject: [PATCH 5/5] Use 'or' syntax

---
 buildable.nix | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/buildable.nix b/buildable.nix
index 9445e5f..2b61b1f 100644
--- a/buildable.nix
+++ b/buildable.nix
@@ -16,8 +16,8 @@ let
       )
     );
   isReserved = n: builtins.elem n ["lib" "overlays" "modules"];
-  isBroken = p: ({ meta.broken = false; } // p).meta.broken;
-  isFree = p: ({ meta.license.free = true; } // p).meta.license.free;
+  isBroken = p: p.meta.broken or false;
+  isFree = p: p.meta.license.free or true;
 in filterSet
      (n: !(isReserved n)) # filter out non-packages
      (p: (builtins.isAttrs p)