Support loading multiple patches.

.github/workflows/main.yml

@@ -1,4 +1,7 @@
-on: [push, pull_request]
+on:
+  pull_request:
+  push:
+    branches: [master]
 name: Test
 jobs:
   test:

README.md

@@ -61,13 +61,15 @@ files.
 
 ### yarn v2+
 
-yarn 2+ have native support for patching dependencies via [`yarn patch`](https://yarnpkg.com/cli/patch).
-You do not need to use patch-package on these projects.
+yarn 2+ have native support for patching dependencies via
+[`yarn patch`](https://yarnpkg.com/cli/patch). You do not need to use
+patch-package on these projects.
 
 ### pnpm
 
-pnpm has native support for patching dependencies via [`pnpm patch`](https://pnpm.io/cli/patch).
-You do not need to use patch-package on these projects.
+pnpm has native support for patching dependencies via
+[`pnpm patch`](https://pnpm.io/cli/patch). You do not need to use patch-package
+on these projects.
 
 ### Heroku
 
@@ -88,30 +90,38 @@ details.
   Otherwise if you update a patch then the change may not be reflected on
   subsequent CI runs.
 
-
 ### CircleCI
-Create a hash of your patches before loading/saving your cache. If using a Linux machine, run `md5sum patches/* > patches.hash`. If running on a macOS machine,  use `md5 patches/* > patches.hash`
+
+Create a hash of your patches before loading/saving your cache. If using a Linux
+machine, run `md5sum patches/* > patches.hash`. If running on a macOS machine,
+use `md5 patches/* > patches.hash`
+
 ```yaml
 - run:
     name: patch-package hash
     command: md5sum patches/* > patches.hash
 ```
 
 Then, update your hash key to include a checksum of that file:
+
 ```yaml
 - restore_cache:
-    key: app-node_modules-v1-{{ checksum "yarn.lock" }}-{{ checksum "patches.hash" }}
-```  
+    key:
+      app-node_modules-v1-{{ checksum "yarn.lock" }}-{{ checksum "patches.hash"
+      }}
+```
 
 As well as the save_cache
+
 ```yaml
 - save_cache:
-    key: app-node_modules-v1-{{ checksum "yarn.lock" }}-{{ checksum "patches.hash" }}
+    key:
+      app-node_modules-v1-{{ checksum "yarn.lock" }}-{{ checksum "patches.hash"
+      }}
     paths:
       - ./node_modules
 ```
 
-
 ## Usage
 
 ### Making patches
@@ -248,6 +258,107 @@ to
 This will allow those patch files to be safely ignored when
 `NODE_ENV=production`.
 
+### Creating multiple patches for the same package
+
+_💡 This is an advanced feature and is not recommended unless you really, really
+need it._
+
+Let's say you have a patch for react-native called
+
+- `patches/react-native+0.72.0.patch`
+
+If you want to add another patch file to `react-native`, you can use the
+`--append` flag while supplying a name for the patch.
+
+Just make you changes inside `node_modules/react-native` then run e.g.
+
+    npx patch-package react-native --append 'fix-touchable-opacity'
+
+This will create a new patch file while renaming the old patch file so that you
+now have:
+
+- `patches/react-native+0.72.0+001+initial.patch`
+- `patches/react-native+0.72.0+002+fix-touchable-opacity.patch`
+
+The patches are ordered in a sequence, so that they can build on each other if
+necessary. **Think of these as commits in a git history**.
+
+#### Updating a sequenced patch file
+
+If the patch file is the last one in the sequence, you can just make your
+changes inside e.g. `node_modules/react-native` and then run
+
+    npx patch-package react-native
+
+This will update the last patch file in the sequence.
+
+If the patch file is not the last one in the sequence **you need to use the
+`--rebase` feature** to un-apply the succeeding patch files first.
+
+Using the example above, let's say you want to update the `001+initial` patch
+but leave the other patch alone. You can run
+
+    npx patch-package react-native --rebase patches/react-native+0.72.0+001+initial.patch
+
+This will undo the `002-fix-touchable-opacity` patch file. You can then make
+your changes and run
+
+    npx patch-package react-native
+
+to finish the rebase by updating the `001+initial` patch file and re-apply the
+`002-fix-touchable-opacity` patch file, leaving you with all patches applied and
+up-to-date.
+
+#### Inserting a new patch file in the middle of an existing sequence
+
+Using the above example, let's say you want to insert a new patch file between
+the `001+initial` and `002+fix-touchable-opacity` patch files. You can run
+
+    npx patch-package react-native --rebase patches/react-native+0.72.0+001+initial.patch
+
+This will undo the `002-fix-touchable-opacity` patch file. You can then make any
+changes you want to insert in a new patch file and run
+
+    npx patch-package react-native --append 'fix-console-warnings'
+
+This will create a new patch file while renaming any successive patches to
+maintain the sequence order, leaving you with
+
+- `patches/react-native+0.72.0+001+initial.patch`
+- `patches/react-native+0.72.0+002+fix-console-warnings.patch`
+- `patches/react-native+0.72.0+003+fix-touchable-opacity.patch`
+
+To insert a new patch file at the start of the sequence, you can run
+
+    npx patch-package react-native --rebase 0
+
+Which will un-apply all patch files in the sequence. Then follow the process
+above to create a new patch file numbered `001`.
+
+#### Deleting a sequenced patch file
+
+To delete a sequenced patch file, just delete it, then remove and reinstall your
+`node_modules` folder.
+
+If you deleted one of the patch files other than the last one, you don't need to
+update the sequence numbers in the successive patch file names, but you might
+want to do so to keep things tidy.
+
+#### Partially applying a broken patch file
+
+Normally patch application is atomic per patch file. i.e. if a patch file
+contains an error anywhere then none of the changes in the patch file will be
+applied and saved to disk.
+
+This can be problematic if you have a patch with many changes and you want to
+keep some of them and update others.
+
+In this case you can use the `--partial` option. Patch-package will apply as
+many of the changes as it can and then leave it to you to fix the rest.
+
+Any errors encountered will be written to a file `./patch-package-errors.log` to
+help you keep track of what needs fixing.
+
 ## Benefits of patching over forking
 
 - Sometimes forks need extra build steps, e.g. with react-native for Android.

integration-tests/append-patches/__snapshots__/append-patches.test.ts.snap

@@ -0,0 +1,98 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`Test append-patches: 00: basic patch file 1`] = `
+"SNAPSHOT: basic patch file
+left-pad+1.3.0.patch
+END SNAPSHOT"
+`;
+
+exports[`Test append-patches: 01: after appending a patch file 1`] = `
+"SNAPSHOT: after appending a patch file
+left-pad+1.3.0+001+initial.patch
+left-pad+1.3.0+002+MillionDollars.patch
+END SNAPSHOT"
+`;
+
+exports[`Test append-patches: 02: the second patch file should go from patch-package to a million dollars 1`] = `
+"SNAPSHOT: the second patch file should go from patch-package to a million dollars
+diff --git a/node_modules/left-pad/index.js b/node_modules/left-pad/index.js
+index a409e14..73d2a7c 100644
+--- a/node_modules/left-pad/index.js
++++ b/node_modules/left-pad/index.js
+@@ -3,7 +3,7 @@
+      * and/or modify it under the terms of the Do What The Fuck You Want
+      * To Public License, Version 2, as published by Sam Hocevar. See
+      * http://www.wtfpl.net/ for more details. */
+-'use patch-package';
++'use a million dollars';
+ module.exports = leftPad;
+
+ var cache = [
+END SNAPSHOT"
+`;
+
+exports[`Test append-patches: 03: creating a first patch file with --append 1`] = `
+"SNAPSHOT: creating a first patch file with --append
+left-pad+1.3.0+001+FirstPatch.patch
+END SNAPSHOT"
+`;
+
+exports[`Test append-patches: 04: the squashed patch file should go from use strict to a million dollars 1`] = `
+"SNAPSHOT: the squashed patch file should go from use strict to a million dollars
+diff --git a/node_modules/left-pad/index.js b/node_modules/left-pad/index.js
+index e90aec3..73d2a7c 100644
+--- a/node_modules/left-pad/index.js
++++ b/node_modules/left-pad/index.js
+@@ -3,7 +3,7 @@
+      * and/or modify it under the terms of the Do What The Fuck You Want
+      * To Public License, Version 2, as published by Sam Hocevar. See
+      * http://www.wtfpl.net/ for more details. */
+-'use strict';
++'use a million dollars';
+ module.exports = leftPad;
+
+ var cache = [
+END SNAPSHOT"
+`;
+
+exports[`Test append-patches: 05: after appending a billion dollars 1`] = `
+"SNAPSHOT: after appending a billion dollars
+left-pad+1.3.0+001+FirstPatch.patch
+left-pad+1.3.0+002+BillionDollars.patch
+END SNAPSHOT"
+`;
+
+exports[`Test append-patches: 06: after updating the appended patch file to a TRILLION dollars 1`] = `
+"SNAPSHOT: after updating the appended patch file to a TRILLION dollars
+diff --git a/node_modules/left-pad/index.js b/node_modules/left-pad/index.js
+index 73d2a7c..f53ea10 100644
+--- a/node_modules/left-pad/index.js
++++ b/node_modules/left-pad/index.js
+@@ -3,7 +3,7 @@
+      * and/or modify it under the terms of the Do What The Fuck You Want
+      * To Public License, Version 2, as published by Sam Hocevar. See
+      * http://www.wtfpl.net/ for more details. */
+-'use a million dollars';
++'use a trillion dollars';
+ module.exports = leftPad;
+
+ var cache = [
+END SNAPSHOT"
+`;
+
+exports[`Test append-patches: 07: patch-package fails when a patch in the sequence is invalid 1`] = `
+"SNAPSHOT: patch-package fails when a patch in the sequence is invalid
+patch-package 0.0.0
+• Creating temporary folder
+• Installing [email protected] with npm
+• Diffing your files with clean files
+Failed to apply patch left-pad+1.3.0+001+FirstPatch.patch to left-pad
+END SNAPSHOT"
+`;
+
+exports[`Test append-patches: 08: --append is not compatible with --create-issue 1`] = `
+"SNAPSHOT: --append is not compatible with --create-issue
+patch-package 0.0.0
+--create-issue is not compatible with --append.
+END SNAPSHOT"
+`;

integration-tests/append-patches/append-patches.sh

@@ -0,0 +1,84 @@
+#!/bin/bash
+# make sure errors stop the script
+set -e
+
+npm install
+
+echo "add patch-package"
+npm add $1
+
+function patch-package {
+  ./node_modules/.bin/patch-package "$@"
+}
+
+function replace {
+  npx replace "$1" "$2" node_modules/left-pad/index.js
+}
+
+echo "making an initial patch file does not add a sequence number to the file by default"
+replace 'use strict' 'use patch-package'
+
+patch-package left-pad
+
+echo "SNAPSHOT: basic patch file"
+ls patches
+echo "END SNAPSHOT"
+
+echo "using --apend creates a patch file with a sequence number and updates the original patch file"
+
+replace 'use patch-package' 'use a million dollars'
+
+patch-package left-pad --append 'MillionDollars'
+
+echo "SNAPSHOT: after appending a patch file"
+ls patches
+echo "END SNAPSHOT"
+
+echo "SNAPSHOT: the second patch file should go from patch-package to a million dollars"
+cat patches/left-pad*MillionDollars.patch
+echo "END SNAPSHOT"
+
+echo "we can squash the patches together by deleting the patch files"
+rm patches/left-pad*patch
+
+patch-package left-pad --append 'FirstPatch'
+
+echo "SNAPSHOT: creating a first patch file with --append"
+ls patches
+echo "END SNAPSHOT"
+
+echo "SNAPSHOT: the squashed patch file should go from use strict to a million dollars"
+cat patches/left-pad*FirstPatch.patch
+echo "END SNAPSHOT"
+
+echo "i can update an appended patch file"
+
+replace 'use a million dollars' 'use a billion dollars'
+
+patch-package left-pad --append 'BillionDollars'
+
+echo "SNAPSHOT: after appending a billion dollars"
+ls patches
+echo "END SNAPSHOT"
+
+replace 'use a billion dollars' 'use a trillion dollars'
+patch-package left-pad 
+
+echo "SNAPSHOT: after updating the appended patch file to a TRILLION dollars"
+cat patches/left-pad*BillionDollars.patch
+echo "END SNAPSHOT"
+
+echo "if one of the patches in the sequence is invalid, the sequence is not applied"
+npx replace 'use strict' 'use bananas'  patches/*FirstPatch.patch
+
+echo "SNAPSHOT: patch-package fails when a patch in the sequence is invalid"
+if patch-package left-pad --append 'Bananas' ; then
+  exit 1
+fi
+echo "END SNAPSHOT"
+
+echo "SNAPSHOT: --append is not compatible with --create-issue"
+if patch-package left-pad --append 'Bananas' --create-issue ; then
+  exit 1
+fi
+echo "END SNAPSHOT"

integration-tests/delete-old-patch-files/delete-old-patch-files.test.ts → integration-tests/append-patches/append-patches.test.ts

@@ -1,5 +1,5 @@
 import { runIntegrationTest } from "../runIntegrationTest"
 runIntegrationTest({
-  projectName: "delete-old-patch-files",
-  shouldProduceSnapshots: false,
+  projectName: "append-patches",
+  shouldProduceSnapshots: true,
 })