freshen up README

update flakes

.github/workflows/test.yml

@@ -12,7 +12,7 @@ jobs:
         os: [ubuntu-latest, macos-latest]
     runs-on: ${{ matrix.os }}
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v2.3.4
     - run: yarn install --frozen-lockfile
     - run: yarn build
     - name: Install Nix
@@ -31,7 +31,7 @@ jobs:
         os: [ubuntu-latest, macos-latest]
     runs-on: ${{ matrix.os }}
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v2.3.4
     - run: yarn install --frozen-lockfile
     - run: yarn build
     - name: Install Nix
@@ -47,7 +47,7 @@ jobs:
         os: [ubuntu-latest, macos-latest]
     runs-on: ${{ matrix.os }}
     steps:
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v2.3.4
     - run: yarn install --frozen-lockfile
     - run: yarn build
     - name: Install Nix
@@ -65,16 +65,31 @@ jobs:
         os: [ubuntu-latest, macos-latest]
     runs-on: ${{ matrix.os }}
     steps:
-    - uses: actions/checkout@v2
-      with:
-        # Nix Flakes doesn't work on shallow clones
-        fetch-depth: 0
+    - uses: actions/checkout@v2.3.4
     - run: yarn install --frozen-lockfile
     - run: yarn build
     - name: Install Nix
       uses: ./
       with:
-        install_url: https://github.com/numtide/nix-flakes-installer/releases/download/nix-2.4pre20201221_9fab14a/install
+        install_url: https://nixos-nix-install-tests.cachix.org/serve/lb41az54kzk6j12p81br4bczary7m145/install
+        install_options: '--tarball-url-prefix https://nixos-nix-install-tests.cachix.org/serve'
         extra_nix_config: |
           experimental-features = nix-command flakes
     - run: nix flake show github:NixOS/nixpkgs
+
+  installer-options:
+    strategy:
+      matrix:
+        os: [ubuntu-latest, macos-latest]
+    runs-on: ${{ matrix.os }}
+    steps:
+    - uses: actions/checkout@v2
+    - run: yarn install --frozen-lockfile
+    - run: yarn build
+    - name: Install Nix
+      uses: ./
+      with: 
+        nix_path: nixpkgs=channel:nixos-20.03
+        install_url: https://nixos-nix-install-tests.cachix.org/serve/lb41az54kzk6j12p81br4bczary7m145/install
+        install_options: '--tarball-url-prefix https://nixos-nix-install-tests.cachix.org/serve'
+    - run: nix-build test.nix

README.md

@@ -51,18 +51,18 @@ jobs:
   tests:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v2
-      with:
-          # Nix Flakes doesn't work on shallow clones
-          fetch-depth: 0
+    - uses: actions/checkout@v2.3.4
     - uses: cachix/install-nix-action@v12
       with:
-        install_url: https://github.com/numtide/nix-flakes-installer/releases/download/nix-2.4pre20201221_9fab14a/install
+        install_url: https://nixos-nix-install-tests.cachix.org/serve/lb41az54kzk6j12p81br4bczary7m145/install
+        install_options: '--tarball-url-prefix https://nixos-nix-install-tests.cachix.org/serve'
         extra_nix_config: |
           experimental-features = nix-command flakes
     - run: nix-build
 ```
 
+To install Nix from any commit, go to [the corresponding installer_test action](https://github.com/NixOS/nix/runs/2219534360) and click on "Run cachix/install-nix-action@XX" step and expand the first line.
+
 ## Inputs (specify using `with:`)
 
 - `install_url`: specify URL to install Nix from (useful for testing non-stable releases or pinning Nix for example https://releases.nixos.org/nix/nix-2.3.7/install)
@@ -75,10 +75,6 @@ jobs:
 
 ## FAQ
 
-### Is it possible to run NixOS tests / Qemu+KVM with GitHub Actions?
-
-[Currently GitHub Actions are not running on Azure instance types that support nested virtualization](https://github.com/actions/virtual-environments/issues/183#issuecomment-610723516).
-
 ### How do I print nixpkgs version I have configured?
 
 
@@ -94,7 +90,8 @@ With the following inputs:
         extra_nix_config: "system-features = nixos-test benchmark big-parallel kvm"
 ```
 
-Note that there's no hardware acceleration on GitHub Actions.
+
+[Note that there's no hardware acceleration on GitHub Actions.](https://github.com/actions/virtual-environments/issues/183#issuecomment-610723516).
 
 ### How can I install packages via nix-env from the specified `nix_path`?
 

lib/install-nix.sh

@@ -28,7 +28,8 @@ installer_options=(
   --nix-extra-conf-file /tmp/nix.conf
 )
 if [[ $INPUT_INSTALL_OPTIONS != "" ]]; then
-  installer_options=("${installer_options[@]}" "${INPUT_INSTALL_OPTIONS[@]}")
+  IFS=' ' read -r -a extra_installer_options <<< $INPUT_INSTALL_OPTIONS
+  installer_options=("${extra_installer_options[@]}" "${installer_options[@]}")
 fi
 
 echo "installer options: ${installer_options[@]}"

yarn.lock

@@ -3630,9 +3630,9 @@ xml-name-validator@^3.0.0:
   integrity sha512-A5CUptxDsvxKJEU3yO6DuWBSJz/qizqzJKOMIfUJHETbBw/sFaDxgd6fxm1ewUaM0jZ444Fc5vC5ROYurg/4Pw==
 
 y18n@^4.0.0:
-  version "4.0.0"
-  resolved "https://registry.yarnpkg.com/y18n/-/y18n-4.0.0.tgz#95ef94f85ecc81d007c264e190a120f0a3c8566b"
-  integrity sha512-r9S/ZyXu/Xu9q1tYlpsLIsa3EeLXXk0VwlxqTcFRfg9EhMW+17kbt9G0NrgCmhGb5vT2hyhJZLfDGx+7+5Uj/w==
+  version "4.0.1"
+  resolved "https://registry.yarnpkg.com/y18n/-/y18n-4.0.1.tgz#8db2b83c31c5d75099bb890b23f3094891e247d4"
+  integrity sha512-wNcy4NvjMYL8gogWWYAO7ZFWFfHcbdbE57tZO8e4cbpj8tfUcwrwqSl3ad8HxpYWCdXcJUCeKKZS62Av1affwQ==
 
 yallist@^3.0.0, yallist@^3.0.3:
   version "3.1.0"