tool/*: remove dependency on redo for tooling (#183)

CONTRIBUTING.md

@@ -11,15 +11,15 @@ A vsix build can be produced by running `./tool/yarn vsce package --allow-star-a
 
 ## Development tools
 
-Following the [Tailscale OSS](https://github.com/tailscale/tailscale) repository, we use a `./tool` directory to manage tool dependencies. Versions are pinned via `*.rev` files in the projects' root and installed via `./tool/redo.sh` using the `*.cmd.do` files also in the project's root.
+Following the [Tailscale OSS](https://github.com/tailscale/tailscale) repository, we use a `./tool` directory to manage tool dependencies. Versions are pinned via `*.rev` files in the projects' root and installed on demand.
 
 Flakes are provided for Nix users, with `nix develop` for the environment.
 
 The following tools are available:
 
-- `./tool/node` - [Node](https://nodejs.org/) for future JavaScript tooling
+- `./tool/Go` - [Go](https://go.dev/) for tsrelay backend
+- `./tool/node` - [Node](https://nodejs.org/) for JavaScript tooling
 - `./tool/yarn` - [Yarn](https://yarnpkg.com/) package manager
-- `./tool/redo.sh` - [Redo](https://github.com/apenwarr/redo) build/automation tool (for deps)
 
 If available, [direnv](https://direnv.net/) will place these tools in your PATH per our `.envrc` config. Installation instructions for direnv are available [here](https://direnv.net/docs/installation.html).
 

tool/node

@@ -1,12 +1,60 @@
-#!/bin/sh
+#!/usr/bin/env bash
 # Run a command with our local node install, rather than any globally installed
 # instance.
 
-set -eu
+set -euo pipefail
 
-cd $(dirname "$0")/..
-./do node.cmd
-read -r NODE < node.cmd
-cd - > /dev/null
+if [[ "${CI:-}" == "true" ]]; then
+    set -x
+fi
 
-exec /usr/bin/env PATH="$(dirname $NODE):$PATH" "$NODE" "$@"
+(
+    if [[ "${CI:-}" == "true" ]]; then
+        set -x
+    fi
+
+    repo_root="${BASH_SOURCE%/*}/../"
+    cd "$repo_root"
+
+    cachedir="$HOME/.cache/tailscale-node"
+    tarball="${cachedir}.tar.gz"
+
+    read -r want_rev <node.rev
+
+    got_rev=""
+    if [[ -x "${cachedir}/bin/node" ]]; then
+        got_rev=$("${cachedir}/bin/node" --version)
+        got_rev="${got_rev#v}" # trim the leading 'v'
+    fi
+
+    if [[ "$want_rev" != "$got_rev" ]]; then
+        rm -rf "$cachedir" "$tarball"
+        if [[ -n "${IN_NIX_SHELL:-}" ]]; then
+            nix_node="$(which -a node | grep /nix/store | head -1)"
+            nix_node="${nix_node%/bin/node}"
+            nix_node_rev="${nix_node##*-}"
+            if [[ "$nix_node_rev" != "$want_rev" ]]; then
+                echo "Wrong node version in Nix, got $nix_node_rev want $want_rev" >&2
+		        exit 1
+            fi
+            ln -sf "$nix_node" "$cachedir"
+        else
+            # works for "linux" and "darwin"
+            OS=$(uname -s | tr A-Z a-z)
+            ARCH=$(uname -m)
+            if [ "$ARCH" = "x86_64" ]; then
+                ARCH="x64"
+            fi
+            if [ "$ARCH" = "aarch64" ]; then
+                ARCH="arm64"
+            fi
+            mkdir -p "$cachedir"
+            curl -f -L -o "$tarball" "https://nodejs.org/dist/v${want_rev}/node-v${want_rev}-${OS}-${ARCH}.tar.gz"
+            (cd "$cachedir" && tar --strip-components=1 -xf "$tarball")
+            rm -f "$tarball"
+        fi
+    fi
+)
+
+export PATH="$HOME/.cache/tailscale-node/bin:$PATH"
+exec "$HOME/.cache/tailscale-node/bin/node" "$@"

tool/yarn

@@ -1,13 +1,44 @@
-#!/bin/sh
+#!/usr/bin/env bash
 # Run a command with our local yarn install, rather than any globally installed
 # instance.
 
-set -eu
+set -euo pipefail
 
-cd $(dirname "$0")/..
-./do yarn.cmd node.cmd
-read -r YARN < yarn.cmd
-read -r NODE < node.cmd
-cd - > /dev/null
+if [[ "${CI:-}" == "true" ]]; then
+    set -x
+fi
+
+(
+    if [[ "${CI:-}" == "true" ]]; then
+        set -x
+    fi
+
+    repo_root="${BASH_SOURCE%/*}/../"
+    cd "$repo_root"
+
+    ./tool/node --version >/dev/null # Ensure node is unpacked and ready
+
+    cachedir="$HOME/.cache/tailscale-yarn"
+    tarball="${cachedir}.tar.gz"
+
+    read -r want_rev <yarn.rev
+
+    got_rev=""
+    if [[ -x "${cachedir}/bin/yarn" ]]; then
+        got_rev=$(PATH="$HOME/.cache/tailscale-node/bin:$PATH" "${cachedir}/bin/yarn" --version)
+    fi
+
+    if [[ "$want_rev" != "$got_rev" ]]; then
+        rm -rf "$cachedir" "$tarball"
+        mkdir -p "$cachedir"
+        curl -f -L -o "$tarball" "https://github.com/yarnpkg/yarn/releases/download/v${want_rev}/yarn-v${want_rev}.tar.gz"
+        (cd "$cachedir" && tar --strip-components=1 -xf "$tarball")
+        rm -f "$tarball"
+    fi
+)
+
+# Deliberately not using cachedir here, to keep the environment
+# completely pristine for execution of yarn.
+export PATH="$HOME/.cache/tailscale-node/bin:$HOME/.cache/tailscale-yarn/bin:$PATH"
+exec "$HOME/.cache/tailscale-yarn/bin/yarn" "$@"
 
-exec /usr/bin/env PATH="$(dirname $NODE):$PATH" "$YARN" "$@"