Attempt to support vscode extensions.

.envrc

@@ -0,0 +1 @@
+use flake

examples/vscode-exts/flake.nix

@@ -0,0 +1,12 @@
+{
+  inputs.nixpkgs.url = "nixpkgs/nixos-unstable";
+  inputs.organist.url = "github:nickel-lang/organist";
+
+  nixConfig = {
+    extra-substituters = ["https://organist.cachix.org"];
+    extra-trusted-public-keys = ["organist.cachix.org-1:GB9gOx3rbGl7YEh6DwOscD1+E/Gc5ZCnzqwObNH2Faw="];
+  };
+
+  outputs = {organist, ...} @ inputs:
+    organist.flake.outputsFromNickel ./. inputs {};
+}

examples/vscode-exts/nickel.lock.ncl

@@ -0,0 +1,3 @@
+{
+  organist = import "../../lib/organist.ncl",
+}

examples/vscode-exts/project.ncl

@@ -0,0 +1,29 @@
+let inputs = import "./nickel.lock.ncl" in
+let organist = inputs.organist in
+
+{
+  shells = organist.shells.Bash,
+
+  shells.dev = {
+    packages.hello = organist.import_nix "nixpkgs#hello",  
+  },
+
+  vscode = {
+    extensions = {
+      "nickel" = {
+        publisher = "Tweag",
+        name = "vscode-nickel",
+        version = "0.3.0",
+        sha256 = "sha256-OntQfxh51B3x92IE4y62bw8csBGukqUzmUJIr/rGioU=",
+      },
+      "test" = {
+        name = "vscode-markdownlint",
+        publisher = "DavidAnson",
+        version = "0.55.0",
+        sha256 = "sha256-slfHfRPcuRu+649n6kAr2bv9H6J+DvYVN/ysq1QpPQM=",
+      },
+    },
+  },
+}
+  | organist.OrganistExpression
+  & organist.tools.vscode.Schema

lib/organist.ncl

@@ -9,6 +9,7 @@
 
   tools.editorconfig = import "./editorconfig.ncl",
   tools.direnv = import "./direnv.ncl",
+  tools.vscode = import "./vscode.ncl",
 }
 #TODO: currently, Nickel forbids doc at the toplevel. It's most definitely
 # temporary, as the implementation of RFC005 is ongoing. Once the capability is

lib/schema.ncl

@@ -1,5 +1,6 @@
 let nix = import "./nix-interop/nix.ncl" in
 let filegen = import "files.ncl" in
+let vscode = import "vscode.ncl" in
 {
   OrganistShells = {
     dev

lib/vscode.ncl

@@ -0,0 +1,56 @@
+let nix = import "./nix-interop/nix.ncl" in
+let ExtensionFromMarketplace = {
+  publisher | String,
+  name | String,
+  version | String,
+  sha256 | String
+} in
+let VSCodeSchema = {
+  extensions
+  | doc "Extensions to install locally in the workspace"
+  | { _ : ExtensionFromMarketplace }
+  | default = {}
+} in
+let BuiltExtensionDetails = {
+  name | String,
+  path | nix.derivation.NixString,
+} in
+let buildExtension : String -> ExtensionFromMarketplace -> BuiltExtensionDetails = fun extName efm =>
+      { name = extName,
+      path = nix.derivation.CallNix & { function = m%"
+          {vscode-utils, extension-ref}:
+            vscode-utils.buildVscodeMarketplaceExtension
+            { mktplcRef = extension-ref; }
+        "%,
+        args = {
+            vscode-utils = nix.import_nix "nixpkgs#vscode-utils",
+            extension-ref = {
+              publisher = efm.publisher,
+              name = efm.name,
+              version = efm.version,
+              sha256 = efm.sha256
+            },
+          }
+      }} | BuiltExtensionDetails in
+let regenerate-vscode | { _ : ExtensionFromMarketplace} -> nix.derivation.Derivation = fun exts =>
+  { name = "regenerate-vscode",
+    content.text = exts
+      |> std.record.to_array
+      |> std.array.map (fun {field = extName, value = ext} => buildExtension extName ext)
+      |> std.array.fold_left
+        ( fun acc elt =>
+          nix-s%"
+            %{acc}
+            ln -sf %{elt.path}/share/vscode/extensions/* ".vscode/extensions/" 
+          "%)
+          "",
+  } | nix.builders.ShellApplication
+in {
+  Schema = {
+    vscode | doc m%"
+      VSCode configuration
+      "% | VSCodeSchema | default
+        = {},
+    flake.apps.regenerate-vscode.program = nix-s%"%{regenerate-vscode vscode.extensions}/bin/regenerate-vscode"%,
+  },
+}