feat(dart): create Dart feature

.github/workflows/test.yml

@@ -13,8 +13,7 @@ jobs:
     strategy:
       matrix:
         features:
-          # - color
-          # - hello
+          - dart
         baseImage:
           - debian:latest
           - ubuntu:latest
@@ -34,8 +33,7 @@ jobs:
     strategy:
       matrix:
         features:
-          # - color
-          # - hello
+          - dart
     steps:
       - uses: actions/checkout@v3
 

src/dart/NOTES.md

@@ -0,0 +1,25 @@
+<!-- markdownlint-disable MD041 MD033 -->
+
+<div align="center">
+
+[![Dart website](https://thum.io/get/width/800/crop/600/noanimate/https://dart.dev/)](https://dart.dev/)
+
+</div>
+
+> Dart is a client-optimized language for fast apps on any platform
+
+&mdash; [Dart programming language | Dart]
+
+This feature installs the Dart SDK using the official installer script. You can
+choose to pin a specific version with the `version` input. You might also want
+to check out [Flutter] if you're interested in Dart.
+
+🆘 If you're having trouble with this feature, [open a Discussion] or [open an
+Issue]! We'd be happy to fix bugs! 🐛
+
+<!-- prettier-ignore-start -->
+[Dart programming language | Dart]: https://dart.dev/
+[Flutter]: https://flutter.dev/
+[open a Discussion]: https://github.com/devcontainers-community/features/discussions/new?category=q-a
+[open an Issue]: https://github.com/devcontainers-community/features/issues/new
+<!-- prettier-ignore-end -->

src/dart/_common.sh

@@ -0,0 +1,24 @@
+updaterc() {
+    echo "Updating /etc/bash.bashrc and /etc/zsh/zshrc..."
+    if [[ "$(cat /etc/bash.bashrc)" != *"$1"* ]]; then
+        echo -e "$1" >> /etc/bash.bashrc
+    fi
+    if [ -f "/etc/zsh/zshrc" ] && [[ "$(cat /etc/zsh/zshrc)" != *"$1"* ]]; then
+        echo -e "$1" >> /etc/zsh/zshrc
+    fi
+}
+
+apt_get_update() {
+    if [ "$(find /var/lib/apt/lists/* | wc -l)" = "0" ]; then
+        echo "Running apt-get update..."
+        apt-get update -y
+    fi
+}
+
+# Checks if packages are installed and installs them if not
+check_packages() {
+    if ! dpkg -s "$@" > /dev/null 2>&1; then
+        apt_get_update
+        apt-get -y install --no-install-recommends "$@"
+    fi
+}

src/dart/devcontainer-feature.json

@@ -0,0 +1,18 @@
+{
+  "id": "dart",
+  "name": "Dart",
+  "description": "Installs the Dart SDK",
+  "version": "1.0.0",
+  "options": {
+    "version": {
+      "description": "Dart version",
+      "type": "string",
+      "default": "latest"
+    }
+  },
+  "customizations": {
+    "vscode": {
+      "extensions": ["dart-code.dart-code"]
+    }
+  }
+}

src/dart/install.sh

@@ -0,0 +1,20 @@
+#!/bin/bash
+set -e
+source _common.sh
+
+check_packages wget gpg apt-transport-https ca-certificates
+
+# https://dart.dev/get-dart
+wget -qO- https://dl-ssl.google.com/linux/linux_signing_key.pub | gpg --dearmor -o /usr/share/keyrings/dart.gpg
+echo 'deb [signed-by=/usr/share/keyrings/dart.gpg arch=amd64] https://storage.googleapis.com/download.dartlang.org/linux/debian stable main' | tee /etc/apt/sources.list.d/dart_stable.list
+
+apt-get update
+if [[ -z $VERSION || $VERSION == latest ]]; then
+  apt-get install dart
+else
+  apt-get install "dart=$VERSION"
+fi
+
+# Now that we have Dart installed to /usr/lib/dart/bin, we need to expose that
+# to future shell sessions via $PATH.
+updaterc 'export PATH="$PATH:/usr/lib/dart/bin"'

test/dart/test.sh

@@ -0,0 +1,7 @@
+#!/bin/bash
+set -e
+source dev-container-features-test-lib
+
+check 'dart' dart --version
+
+reportResults