From 7e8b2b7e988cfd7e8e0745f0af3eb42b6a1918cb Mon Sep 17 00:00:00 2001
From: Jan Tojnar <jtojnar@gmail.com>
Date: Tue, 15 Dec 2020 17:42:21 +0100
Subject: [PATCH 1/2] phpPackages: convert to scope

This will make it easier to make overridable.

Had to rename `packages` attribute to `tools` in `php-packages.nix` because `packages` is shadowed by `makeScope`.
---
 pkgs/development/interpreters/php/generic.nix |  5 +++--
 pkgs/top-level/php-packages.nix               | 15 +++++----------
 2 files changed, 8 insertions(+), 12 deletions(-)

diff --git a/pkgs/development/interpreters/php/generic.nix b/pkgs/development/interpreters/php/generic.nix
index 4a96abcf9b69328..a3559de94400756 100644
--- a/pkgs/development/interpreters/php/generic.nix
+++ b/pkgs/development/interpreters/php/generic.nix
@@ -49,7 +49,7 @@ let
               php = generic filteredArgs;
 
               php-packages = (callPackage ../../../top-level/php-packages.nix {
-                php = phpWithExtensions;
+                phpPackage = phpWithExtensions;
               });
 
               allExtensionFunctions = prevExtensionFunctions ++ [ extensions ];
@@ -112,7 +112,8 @@ let
                   phpIni = "${phpWithExtensions}/lib/php.ini";
                   unwrapped = php;
                   tests = nixosTests.php;
-                  inherit (php-packages) packages extensions buildPecl;
+                  inherit (php-packages) extensions buildPecl;
+                  packages = php-packages.tools;
                   meta = php.meta // {
                     outputsToInstall = [ "out" ];
                   };
diff --git a/pkgs/top-level/php-packages.nix b/pkgs/top-level/php-packages.nix
index d5bebb9bd847427..cc8ba346ae56c57 100644
--- a/pkgs/top-level/php-packages.nix
+++ b/pkgs/top-level/php-packages.nix
@@ -1,4 +1,4 @@
-{ stdenv, lib, pkgs, fetchgit, php, autoconf, pkgconfig, re2c
+{ stdenv, lib, pkgs, fetchgit, phpPackage, autoconf, pkgconfig, re2c
 , gettext, bzip2, curl, libxml2, openssl, gmp, icu64, oniguruma, libsodium
 , html-tidy, libzip, zlib, pcre, pcre2, libxslt, aspell, openldap, cyrus_sasl
 , uwimap, pam, libiconv, enchant1, libXpm, gd, libwebp, libjpeg, libpng
@@ -6,7 +6,7 @@
 , readline, rsync, fetchpatch, valgrind
 }:
 
-let
+lib.makeScope pkgs.newScope (self: with self; {
   buildPecl = import ../build-support/build-pecl.nix {
     php = php.unwrapped;
     inherit lib;
@@ -21,15 +21,10 @@ let
 
   pcre' = if (lib.versionAtLeast php.version "7.3") then pcre2 else pcre;
 
-  callPackage = pkgs.newScope {
-    inherit mkDerivation php buildPecl pcre';
-  };
-in
-{
-  inherit buildPecl;
+  php = phpPackage;
 
   # This is a set of interactive tools based on PHP.
-  packages = {
+  tools = {
     box = callPackage ../development/php-packages/box { };
 
     composer = callPackage ../development/php-packages/composer { };
@@ -550,4 +545,4 @@ in
 
     # Produce the final attribute set of all extensions defined.
   in builtins.listToAttrs namedExtensions);
-}
+})

From b2594c71c248b78b8526a62f43ad74151a31ac3a Mon Sep 17 00:00:00 2001
From: Jan Tojnar <jtojnar@gmail.com>
Date: Wed, 16 Dec 2020 00:06:42 +0100
Subject: [PATCH 2/2] php.packages: Make packages overridable

This will allow patching extensions without having to manually having to patch all occurrences in the dependency tree.
---
 doc/languages-frameworks/php.section.md       | 18 ++++++++++++++++++
 pkgs/development/interpreters/php/generic.nix |  3 ++-
 2 files changed, 20 insertions(+), 1 deletion(-)

diff --git a/doc/languages-frameworks/php.section.md b/doc/languages-frameworks/php.section.md
index 763beeb59358311..5977363323f18f0 100644
--- a/doc/languages-frameworks/php.section.md
+++ b/doc/languages-frameworks/php.section.md
@@ -135,3 +135,21 @@ Example of building `composer` with additional extensions:
   enabled ++ (with all; [ imagick redis ]))
 ).packages.composer
 ```
+
+### Overriding PHP packages {#ssec-php-user-guide-overriding-packages}
+
+`php-packages.nix` form a scope, allowing us to override the packages defined within. For example, to apply a patch to a `mysqlnd` extension, you can simply pass an overlay-style function to `php`’s `packageOverrides` argument:
+
+```nix
+php.override {
+  packageOverrides = final: prev: {
+    extensions = prev.extensions // {
+      mysqlnd = prev.extensions.mysqlnd.overrideAttrs (attrs: {
+        patches = attrs.patches or [] ++ [
+          …
+        ];
+      });
+    };
+  };
+}
+```
diff --git a/pkgs/development/interpreters/php/generic.nix b/pkgs/development/interpreters/php/generic.nix
index a3559de94400756..82134e14406f897 100644
--- a/pkgs/development/interpreters/php/generic.nix
+++ b/pkgs/development/interpreters/php/generic.nix
@@ -13,6 +13,7 @@ let
     , version
     , sha256
     , extraPatches ? []
+    , packageOverrides ? (final: prev: {})
 
     # Sapi flags
     , cgiSupport ? true
@@ -50,7 +51,7 @@ let
 
               php-packages = (callPackage ../../../top-level/php-packages.nix {
                 phpPackage = phpWithExtensions;
-              });
+              }).overrideScope' packageOverrides;
 
               allExtensionFunctions = prevExtensionFunctions ++ [ extensions ];
               enabledExtensions =