feat: add build-time variables

.gitignore

@@ -7,3 +7,6 @@ dist/
 .swiftpm/
 .netrc
 .vscode
+
+# Generated files
+Sources/BuildInfo.swift

Makefile

@@ -1,12 +1,20 @@
+VERSION := 1.0.0
+BUILD_INFO_FILE := Sources/BuildInfo.swift
+
 .PHONY: help
 help: ## print this message
 	@awk \
 		'BEGIN {FS = ":.*?## "} /^[a-zA-Z_-]+:.*?## / \
 		{printf "\033[33m%-15s\033[0m %s\n", $$1, $$2}' \
 		$(MAKEFILE_LIST)
 
+
+.PHONY: generate
+generate: ## generate build info
+	@bash scripts/generate.bash $(VERSION)
+
 .PHONY: build
-build: ## build runon
+build: generate ## build runon
 	swift build
 	rm -rf ./dist
 	mkdir ./dist
@@ -15,7 +23,7 @@ build: ## build runon
 	chmod +x ./dist/runon
 
 .PHONY: lint
-lint: ## check code style
+lint: generate ## check code style
 	swiftlint lint --config .swiftlint.yaml .
 	shellcheck -a scripts/runon.bash
 
@@ -27,5 +35,5 @@ install: ## install runon to the system
 	cp dist/* /usr/local/bin/
 
 .PHONY: test
-test: ## run tests
+test: generate ## run tests
 	swift test

Package.swift

@@ -25,7 +25,8 @@ let package = Package(
                 .product(name: "SimplyCoreAudio", package: "SimplyCoreAudio"),
                 .product(name: "Rainbow", package: "Rainbow"),
                 .product(name: "Shellac", package: "swift-shellac"),
-            ]
+            ],
+			exclude: ["BuildInfo.swift.dist"]
         ),
         .testTarget(
             name: "runonTests",

Sources/BuildInfo.swift.dist

@@ -0,0 +1,4 @@
+// This file is autogenerated. Do not edit it by hand.
+let kAppVersion = "$APP_VERSION"
+let kBuildCommit = "$BUILD_COMMIT"
+let kBuildDate: String = "$BUILD_DATE"

Sources/RunOn.swift

@@ -14,7 +14,8 @@ struct RunOn: ParsableCommand {
     static var configuration = CommandConfiguration(
         commandName: "runon-daemon",
         abstract: "A utility for automating actions on system events.",
-        version: "1.0.0",
+        discussion: "VERSION: \(kAppVersion) (\(kBuildCommit))",
+        version: kAppVersion,
         subcommands: [Run.self, Autostart.self, Print.self],
         defaultSubcommand: Run.self
     )

scripts/generate.bash

@@ -0,0 +1,20 @@
+#!/bin/bash
+
+TPL_FILE="Sources/BuildInfo.swift.dist"
+OUT_FILE="Sources/BuildInfo.swift"
+
+if [ ! -f "$TPL_FILE" ]; then
+	echo "File not found: $TPL_FILE"
+	exit 1
+elif [ -z "$1" ]; then
+	echo "Version not specified"
+	exit 1
+fi
+
+set -e
+
+APP_VERSION=${1} \
+BUILD_COMMIT="$(git rev-parse --short HEAD)" \
+BUILD_DATE="$(date -u +"%Y-%m-%dT%H:%M:%SZ")" \
+	envsubst "\$APP_VERSION \$BUILD_COMMIT \$BUILD_DATE" < "$TPL_FILE" > "$OUT_FILE"
+