Add more shellcheck tests

Author: jgarber623-cargosense

test/shellcheck/scenarios.json

@@ -0,0 +1,19 @@
+{
+  "shellcheck-version": {
+    "image": "debian:latest",
+    "features": {
+      "shellcheck": {
+        "version": "0.5.0"
+      }
+    }
+  },
+
+  "shellcheck-install-path": {
+    "image": "debian:latest",
+    "features": {
+      "shellcheck": {
+        "installPath": "/usr/bin"
+      }
+    }
+  }
+}

test/shellcheck/shellcheck-install-path.sh

@@ -0,0 +1,18 @@
+#!/usr/bin/env bash
+
+set -e
+
+# Optional: Import test library bundled with the devcontainer CLI
+# See https://github.com/devcontainers/cli/blob/HEAD/docs/features/test.md#dev-container-features-test-lib
+# Provides the 'check' and 'reportResults' commands.
+# shellcheck source=/dev/null
+source dev-container-features-test-lib
+
+# Feature-specific tests
+# The 'check' command comes from the dev-container-features-test-lib. Syntax is...
+# check <LABEL> <cmd> [args...]
+check "which shellcheck" bash -c "which shellcheck | grep /usr/bin/shellcheck"
+
+# Report result
+# If any of the checks above exited with a non-zero exit code, the test will fail.
+reportResults

test/shellcheck/shellcheck-version.sh

@@ -0,0 +1,18 @@
+#!/usr/bin/env bash
+
+set -e
+
+# Optional: Import test library bundled with the devcontainer CLI
+# See https://github.com/devcontainers/cli/blob/HEAD/docs/features/test.md#dev-container-features-test-lib
+# Provides the 'check' and 'reportResults' commands.
+# shellcheck source=/dev/null
+source dev-container-features-test-lib
+
+# Feature-specific tests
+# The 'check' command comes from the dev-container-features-test-lib. Syntax is...
+# check <LABEL> <cmd> [args...]
+check "version" bash -c "shellcheck --version | grep 0.5.0"
+
+# Report result
+# If any of the checks above exited with a non-zero exit code, the test will fail.
+reportResults